WO2014068591A1

WO2014068591A1 - Integrated wind and solar power system

Info

Publication number: WO2014068591A1
Application number: PCT/IN2013/000661
Authority: WO
Inventors: Praveen Dayaram KAKULTE; Yogesh Jogindernath MEHRA
Original assignee: Kakulte Praveen Dayaram; Mehra Yogesh Jogindernath
Priority date: 2012-11-01
Filing date: 2013-10-30
Publication date: 2014-05-08

Abstract

The present subject matter relates to an integrated wind and solar power system. The system includes a wind turbine (W) having a generator (G), wherein said generator (G) is coupled to one or more generator power output sections. The system further includes a solar power source having one or more solar power output sections. The system further includes a plurality of power lines (P1-Pn) coupled to a common power output section (P) for feeding power to an electric power grid. The system further includes a plurality of switches (SW1-SWn) controlled by a controller (PMCU), each of the plurality of switches having a first input associated with one of said generator power output sections, a second input associated with one of said solar power output sections, and an output associated with one of said plurality of power lines (P1-Pn).

Description

INTEGRATED WIND AND SOLAR POWER SYSTEM

TECHNICAL FIELD

[0001] The present subject matter relates to an integrated wind and solar power system, and. a method of operating the same.

BACKGROUND

[0002] According to commonly known and practiced technology, a modern wind farm comprises a plurality of wind turbines having, for example, AC-DC-AC interfaces between a generator and the grid. Such wind turbines are installed with an adequate spacing between the towers of individual wind turbines, as per conventional design requirements. Generally, each wind turbine comprises a generator, a rectifier, a step-up DC to DC converter, an inverter, and a transformer. Further, each wind turbine comprises a hub, a rotor which is rotatably mounted on a tower, and one or more blades attached to the rotor. The generator of the wind turbine is coupled to the rotor. Each wind turbine in the wind farm is capable of producing power independent of the other turbines in the wind farm as each wind turbine has its "own rectifier and inverter according to the commonly known systems. The respective inverters of each wind turbine are connected either separately to a dedicated transformer or to a combined transformer. The sizing of the wind turbine components, such as the generator, the rectifier, the step-up DC to DC converter, the inverter, and the transformer is determined with respect to power rating or rated power capacity of the said wind turbine. Said components constitute a power processing channel. Effective utilisation of installed capacity of said wind turbine at component level however can remain as low as 25% due to the nature and quantum of wind energy that can be extracted during any time of a day during a year. This means that up to 75% of the built-up power processing capacity of the wind turbine can remain unutilised merely on account of the nature of this natural resource wind.

[0003] For setting up a wind , farm with multiple wind turbines, the other investments are towards land, balance of plant, and associated evacuation infrastructure on the transmission side. Again its design and sizing is based on the compounded capacity and space requirement of individual wind turbines leading to a similar impact of inefficient capacity utilisation at a wind farm level. The yield of the power is generally significantly low as compared to the sizing or dimensioning of the wind farm equipment. For instance, the average yield of power over a year from a wind turbine may be as low as 25% of its rated power. Considering the costs of the land and the investment in the equipment, the return of the investment is generally substantially low, and therefore efforts are constantly being made to increase this return on investment. Intermittent nature of wind influences the power delivery from a wind farm leading to variability in power output with a rare possibility to get such a variation under full control. One suggested way of improving the return on investment and managing variability in load is use of the wind energy in combination with other sources of generation, such as coal, gas, and oil.

[0004] However, the wind speeds vary on a real time basis and are substantially unpredictable. Various methods for wind forecasting exist but the forecasts can be made for a substantially small time frame of, say, about eight hours. Further, the accuracy of such a forecast is substantially low, that is, the actual wind speed is likely to deviate to the extent of 50% from the forecasted wind speed. Therefore, the optimal use of the wind energy in combination with other sources of generation, such as coal, gas, and oil is a challenge for a load management centre, due to the unpredictable nature of availability of the forecasted wind energy at a particular time period. From the cost of energy perspective, wind energy is always preferred; however, if the wind energy forecast fails, then the load management centre cannot ramp up the needed energy from other sources as the supply from these sources need to be forecasted sufficiently in advance, that is, at least two days in advance because of the run-in-time required for the generating plant to start or to stop. This feature of the wind turbine makes the same less preferable and less economical over other sources of power, such as fuel based power plants. Accordingly, there is a major challenge in making the wind power more economical and in assuring the customer's predictable availability of wind power.

SUMMARY

[0005] The present subject matter relates to enhancing capacity utilisation of a built-up capacity of wind turbine installation by fragmenting its power processing channels into multiple divisibles of its full rated capacity, providing avenue to switch one or more of the divided power processing channels for use with another source of energy input, such as solar energy. The wind turbine installation thus operates in a split mode and sizes itself to best fit with pertinent wind energy during, the time. This leads to a higher capacity utilization factor of the split power processing channel used by the wind turbine. At the same time, the other split power processing channels can be used by an array of solar photo voltaic panels thus utilising the total built-up capacity of the said wind turbine effectively and enhancing the overall capacity factor of the so formed wind-solar integrated installation. The proportion of wind to solar can be adequately sized depending upon availability of energy resources at a site. The nature of wind and solar being generally complimentary to each other, the said integration can provide an efficient utilisation of built-up capacity of the wind turbine and provides optimum yield for a wind farm. The present subject matter further provides switching of energy input sources at wind farm level, whereby, power processing channels of a typically deficient wind turbine is used integrally with other turbines or solar arrays. Predictability and forecasting of power output at least during the day due to solar usage provides reliability on base load expectancy, further simplifying the load despatch operations at the load centres.

[0006] According to one embodiment of the present subject matter, an integrated wind and solar power system is provided. The integrated system comprises a wind turbine having a generator, wherein said generator is coupled to one or more generator power output sections, a solar power source having one or more solar power output sections, a plurality of power lines coupled to a common power output section for feeding power to an electric power grid, a plurality of switches, each of the plurality of switches having a first input associated with one of said generator power output sections, a second input associated with one of said solar power output sections, and an output associated with one of said plurality of power lines, and a controller (interchangeably referred to as a power management and control unit or PMCU), configured to selectively switch each of said plurality of switches to one of said generator power output sections and said associated solar output sections, based on anyone or more of input wind power related information, input solar energy related information, and power output information.

[0007] According to the embodiment of the present subject matter indicated above, an integrated wind and solar power system provides an enhanced operation due to the integration of wind power systems and solar power systems by employing said switches which are operated by said controller such that said wind turbine and said solar power source can be optimally associated with one of said plurality of power lines. According to this basic concept, the efficiency of utilizing the provided electrical equipment can be enhanced such that the total efficiency of the above mentioned integrated wind and solar power system increases in relation to the commonly known separate systems.

[0008] According to an embodiment of the present subject matter, said generator comprises a plurality of generator sections, and wherein each of said generator sections is coupled to a corresponding generator power output section.

[0009] According to the above embodiment, the extent of freedom for associating the wind turbine and the solar power source with said power lines is increased as it is no longer required to completely switch on or off said wind turbine. Moreover, the efficiency of the electrical equipment can be enhanced due to the fact that the above mentioned extent of freedom is increased and an operation of the system at an optimum efficiency can be selected due to the above arrangement.

[00010] According to an embodiment of the present subject matter, said solar power source comprises a plurality of solar power converters, and wherein each of said solar power converters is coupled to a corresponding solar power output section. [00011] According to the above embodiment, the extent of freedom to utilize the solar power converters is increased such that the total efficiency of the integrated wind and solar power system can be further optimized.

[00012] According to an embodiment of the present subject matter, the controller is further configured to identify the source of power being processed by each of said power lines being one of said wind turbine and said solar power source.

[00013] With the controller being configured as stated in the above embodiment, it is possible to select the power source from said wind turbine and said solar power source in order to process the output power by a respective power line. Accordingly, it is possible to associate the selected power source to a designated power line in order to enhance the total efficiency of the integrated wind and solar power system. According to an embodiment of the present subject matter, said controller includes a preloaded decision map including a correlation of wind speed and solar radiation with the expected power output from each of said one or more generator power output sections, each of said one or more solar power output sections, and said power output section, wherein said controller periodically updates automatically said preloaded decision map to an updated map capturing seasonal and site specific variations of available wind and solar energy.

[00014] According to the above embodiments, the controller is capable of deciding specific operations of the system based on data relating to an expected power output. Moreover, according to the above embodiment, the information used by the controller is updated automatically such that a kind of learning control is provided for improving the control operation of the controller. ^"Based on the above, the total efficiency of the integrated wind and solar power system can be increased not only instantly but in addition in relation to the long term operation.

[00015] According to an embodiment of the present subject matter, said controller is further configured to process said updated map to forecast a power generation from said wind and solar power system for a user defined period.

[00016] According to the above embodiment, it is possible to define the period for forecasting the power generation such that the extent of freedom of operation of the system is further improved. In particular, it is possible for a user to define such a period in order to make further decisions relating to the operation of associated power sources.

[00017] According to an embodiment of the present subject matter, said controller is configured to perform steps comprising: selectively switching said each of said plurality of switches to couple said one or more of generator power output sections to said associated one or more of said plurality of power lines, so as to first process power available from said generator to one or more of said plurality of power lines; determining a balanced capacity of said plurality of power lines available after utilizing power from said generator; and utilizing said balance capacity of said plurality of power lines by processing power from said one or more solar power output sections.

[00018] According to the above embodiment, it is possible to make optimum use of the electrical equipment, such as said power lines by the operation of the controller for selectively switching said switches in relation to said one or more of generator output sections. Accordingly, the rated power output of said generator sections can be employed for enhancing the efficiency thereof, whereas a balance capacity of said plurality of power lines is employed and further power from said one or more solar power output sections is optimally utilized.

[00019] According to an embodiment of the present subject matter, said controller is configured to detect one or more dysfunctional generator power output sections and accordingly take in circuit one or more functional generator output sections based on said updated map.

[00020] According to the above embodiment, it is possible to maintain the operation of the wind and solar power system even if sections of the wind power system are out of operation. Consequently, an unintended dysfunction or an intended maintenance of generator output sections do not lead to power off times of the entire system and rather the dysfunctional section is not used to produce power which can be supplemented by functional generator power output section.

[00021] According to an embodiment of the present subject matter, said controller is configured to monitor a functional status of said power lines and to switch over to functional power lines when one of said power lines is detected to be dysfunctional.

[00022] According to this embodiment, it is possible to replace a dysfunctional power line by a functional power line such that the overall operation of the power system can be maintained even in a condition of an unintended dysfunction or an intended maintenance of a power line.

[00023] According to an embodiment of the present subject matter, the integrated wind and solar power system further includes at least one DC to DC converter, at least one inverter and at least one transformer.

[00024] According to the above embodiment, an adaptation of properties of power outputs to be supplied to the grid is enabled. Moreover, the combination of the above elements improves the basic function of the integrated wind and solar power system in order to achieve the advantages discussed above.

[00025] According to an embodiment of the present subject matter, a maximum rated power throughput of elements forming said power line is adapted to a maximum power output of said associated generator output section.

[00026] According to the above embodiment, power related properties of elements forming said power line are designed in view of a maximum power output of said associated generator output section. Accordingly, the efficiency of power throughputs based on the previous power output of said associated generator output section can be improved and, at the same time, the efficiency of the generator output section enhanced as it optionally can approach the rated power output thereof.

[00027] According to an embodiment of the present subject matter, a combined rated power capacity of said plurality of power lines is at least equal to a rated capacity of said wind turbine.

[00028] According to the above embodiment, the efficiency of power throughput can be improved due to the operation approaching a rated capacity of the wind turbine.

[00029] According to an embodiment of the present subject matter, said wind and solar power system further includes additional one or more power lines to provide redundancy and a buffer capacity.

[00030] According to the above embodiment, it is crucial to provide a maximum continuity of power generation such that the provision of redundancy and buffer capacity further improves this specific effect of the present subject matter.

[00031] According to an embodiment of the present subject matter, each of that plurality of generator sections is formed by at least one pair of diametrically opposite status including corresponding windings, and outputs AC power to said one or more generator power output section.

[00032] The arrangement of a generator having a plurality of generator sections in the manner explained above provides strictly separate or separable sections of the generator which can be separately controlled, i.e. switched on or off in order to provide generated power or not. Moreover, generators providing AC power operate at high efficiencies which further enhance the total efficiency of the integrated wind and solar power system.

[00033] According to an embodiment of the present subject matter, said generator power output section is coupled to a rectifier, said rectifier providing DC power to said power line.

[00034] According to the above embodiment, DC power is provided by said rectifier, which DC power can be processed by electrical components of the power line such that the combination of wind and solar power can be realized.

[00035] According to an embodiment of the present subject matter, each of said plurality of solar converters comprises one or more solar converter sections which are selectively connected in parallel or in series to each other in order to provide a required DC voltage.

[00036] According to the above embodiment, the DC voltage can be adapted to the requirements of the electrical components of the power lines such that an optimum efficiency of the power lines in view of an optimum DC voltage can be realized.

[00037] According to an embodiment of the present subject matter, each of said solar converters is connected to said associated plurality of switches via a DC-DC converter for adapting said voltage to a predetermined input requirement of said inverter. [00038] According to the above embodiment, the power output of the solar converters can be adapted in voltage in order to provide an optimum efficiency of said inverter, which efficiency depends on input voltage. Accordingly, the overall efficiency of the integrated wind and solar power system can be improved by using a DC-DC converter in the embodiment above.

[00039] According to an embodiment of the present subject matter, said controller is configured, based on a user defined input, to couple a combination of said one or more generator power output sections and said one or more solar power output sections to optimize the cost of power for said user based on a tariff structure.

[00040] According to the above embodiment, , in addition to physical and technical efficiency related information, a tariff structure can be employed in order to optimize the operation of the integrated wind and solar power system. In particular, it is possible to decide based on a variable tariff structure which combination of generator power output sections and solar power output sections is optimum in view of economic requirements.

[00041] According to an embodiment of the present subject matter, said wind and solar power system includes any other power sources of equivalent capacity in addition or as replacement of one or more solar converters.

[00042] According to the above embodiment, it is possible to employ different power sources which can be combined with the above defined integrated wind and solar power system.

[00043] Moreover, it is possible to replace one or more solar converters by power sources different from solar converters, such as conventional power plants, renewable energy based power plants, combined heat and power systems, fuel cells or the like.

[00044] Based on the above embodiment, it is possible to provide an integrated system in which wind power generated by wind turbines can be combined in order to optimize the power output of the integrated system.

[00045] According to an embodiment of the present subject matter, any other power sources include any one more of renewable energy sources. According to this embodiment, the goal of providing alternative power generation systems is achieved by combining wind power and renewable energy sources.

[00046] According to the present subject matter, a method of operating an integrated wind and solar power system is provided, wherein the method comprises the following: obtaining periodically information relating to input wind power, input solar energy and power output of said wind and solar power system, said wind and solar system comprising a generator, wherein said generator, includes one or more generator power output sections, and each of said one or more generator power output sections is switchably coupled to a power line; based on said information relating to input wind power, input solar energy, and power output of said wind and solar system, coupling said one or more generator power output sections by selectively switching to one or more said power lines, and coupling one or more solar power output sections to one or more power lines not coupled to said one or more generator power output sections.

[00047] According to an embodiment of the present subject matter, said power output information of said wind and solar system in said methods includes information related to power output from said plurality of generator power output sections, from said plurality of solar output sections, and from said plurality of power l ines.

[00048] The above explanation of the embodiments can be modified appropriately as long as the modification is covered by the basic concept of the subject matter defined in the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[00049] Fig. la is a diagram showing a comparison of wind and solar power energy available in a predetermined period of time, for example, throughout the year, as per one embodiment of the present subject matter.

[00050] Fig. lb is a diagram showing a comparison of achievable capacities of wind and solar power energy that can be obtained individually, with energy as obtained from system the integrated wind and solar power energy system, as per one embodiment of the present subject matter.

[00051] Fig. 2 is an outline of the integrated wind and solar system showing a wind farm associated with a set of solar panels installed in vacant spaces present in the vicinity of wind turbines according to an embodiment of the present subject-matter.

[00052] Fig. 3a-c is an outline of the integrated wind and solar power system showing an example of the electrical and control related equipment thereof according to an embodiment of the present subject-matter.

[00053] In the following, an embodiment of the present subject matter is explained based on the drawings. It is noted that the drawings show a specific embodiment as explained below. Further alternative modifications of the embodiment which are at least in part not illustrated are specified in the following description and intended to be covered by the subject matter defined in the claims. DESCRIPTION OF THE EMBODIMENT

[00054] According to the basic concept of the present invention, a wind farm comprising a single or plurality of wind turbines is associated with solar power converters in a specific manner in order to enhance the efficient utilization thereof. In the following, the efficient utilization not only relates to an electric efficiency of the power conversion in view of the input solar or wind power in relation to the electric power output, but in addition to the practical utilization of the integrated wind and solar power system with respect to a continuous power output which is required for the practical use of such systems.

[00055] As would be appreciated by a person skilled in the art, variations in the average wind energy available for conversion varies throughout the year. During times when the wind energy is not optimum, the power which can be generated through wind turbines would consequently be less than the rated power. This results in the infrastructure associated with the wind turbine not being effectively utilized, which in turn is likely to increase the overall costs and the return on investments. Fig. la depicts an exemplary graphical representation indicating, at a particular geographical location, the difference between wind power and solar power energy available throughout a predetermined period of time, which in the illustrated example is one year. In Fig. la, available solar power is indicated by function (A), whereas available wind power is indicated by function (B). As can be derived from Fig. la, the solar power, as indicated by the function (A), available from radiation varies with a function over the time, whereas the wind power available by wind power conversion using wind turbines varies with a different function, i.e., the function (B). It can also be observed from the function (B) that the wind power available is high only for a limited duration, as depicted by the period 102. As would be noted, the power that is generated by a wind turbine would be less than the rated capacity of the wind turbine. The function (A) on the other hand depicts the solar radiation that is available in day time. As can be gathered from Fig. l a the solar power generated would also vary as per function (A). As can also be seen, within some durations, the power available from wind and solar radiation is generally complementary, i.e., when the available power is low, the average solar radiation available is high and vice versa.

[00056] In one implementation of the preset subject matter, the power available from wind energy and the solar energy can be integrated during day time. In the night time, since solar energy is not available, therefore wind energy becomes the only source behind output power generated out of the integrated wind and solar energy plant. However, energy stored during day time by the solar power plant in batteries/storage means or energy from any other renewable or non-renewable energy source may be used to achieve maximum capacity utilization of resource of the integrated wind and solar power plant. The integrated wind and solar energy can be obtained based on a summation of the total power that is available from wind power and solar radiation. The integrated wind and solar energy are depicted in Fig. lb as function(C). It is to be noted here that the achievable capacities indicated in the Fig. lb are exemplary in nature. It should be noted that, as a result of the integration the variations in the power obtained are less, i.e., the power generated by - integrating wind and solar energy, as indicated by the function (C), is more consistent when compared to variations in available wind energy, as indicated by the function (B), or solar energy, as indicated by the function (A), when considered independently. This implementation of the present subject matter permitting the use of renewable energy with better prediction or forecast becomes more reliable and thus can result in savings of conventional or fossil fuels.

[00057] In order to clarify the basic concept and the aim of the present subject matter, reference is made to Fig. 2 showing the outline of the integrated wind and solar power system according to the present subject matter. As shown in Fig. 2, a plurality of wind turbines is arranged in a designated area with a predetermined spacing between the wind turbines. Due to the fact that the space requirements of wind turbines including a tower which is erected from the ground is completely different from the space requirements of solar converters, which are in general arranged close to the ground and require a high surface area to convert the radiation, it is possible to efficiently use the designated area by both the wind turbines and the solar converters.

[00058] Consequently, according to the present subject matter, the vacant spaces between wind turbines are utilized for installation of a plurality of solar panels to be dynamically associated with a wind turbine of the farm. The plurality of solar converters can provide extra power of, for example, 50-60% of the associated wind turbines. It may be noted that the average power yield from wind turbines in a wind farm ranges at approximately 25% of its rated power capacity. Accordingly, the plurality of solar converters can provide the above-mentioned extra power of approximately 50-60% of this rated power capacity of the wind farm to complement the power generated by the wind turbines of the wind farm. It is noted that these numbers are only provided for the purpose of explanation and do not restrict the concept of the present subject matter.

[00059] At some geographical locations, the seasonal variation in wind and solar energy may be substantially complementary, e.g. the sum total of energy available from the sun and the wind provides a nearly uniform supply of power during the day and over the year, thereby substantially minimizing the variations over a period. More importantly, the sum total of the power is more than that what is available from only wind or only solar energy. This concept is realized in the integrated wind and solar power system according to the present subject matter.

[00060] According to the present embodiment, which is outlined in Fig. 2, a number n of wind turbines WT1, WT2,..WTn is associated in a wind farm. In one example, n=5. Each of the wind turbines WT1, WT2,..WTn in the wind farm may be associated with a set of solar converters SCI, SC2,...SCn (solar panels or solar panel arrangements) installed in the vacant spaces present in the vicinity of the each of the wind turbines WT1, WT2,..WTn. Alternatively, the solar panels · SCI, SC2,...SCn may also be mounted on the wind turbines WT1, WT2,..WTn, for example, on the tower of the wind turbines WT1 , WT2,..WTn. For example, the solar panel SC2 may be mounted on the tower of the wind turbine WT2. In one embodiment, the solar panel SC2 may be linked to other wind turbines so that when SC2 is not being used in conjunction with WT2 and when one of the other wind turbines, say WTl , is not operational for failure or maintenance reasons, then SC2 can be used in conjunction with the Solar Panel SGI to optimally utilize a common electrical system between the wind turbine WTl and solar panel SC I . In this way, a wind and solar farm of wind turbines WTl, WT2,..WTn and the solar panels SCI, SC2,...SCn can be formed, wherein any one of the wind turbines WTl, WT2,..WTn may be linked with any one the solar panels SCI, SC2,...SCn using computer controlled switches. In addition, the common electrical system between a wind turbine and a solar panel can be optimally utilized by borrowing the services of unused solar panels associated with other wind turbines when required.

[00061] As shown in Fig. 3a-c, the generator in each wind turbine may be designed to include a plurality of generator sections Gl, G2, G3, and Gn. These generator sections can form multiple modular generators and may be created by dividing a stator into a plurality of mutually independent sub-windings and subsequently taking an output from each of the sub-windings, wherein each of said generator sections is coupled to a corresponding generator output section. Each of the sub-windings works as modular generator or generator section. Alternatively, the output of the generator can be divided using rectifies to form the plurality of generator sections Gl ,. G2, G3, and Gn. Further, each modular generator has a power line unit connecting the modular generator to a common power output section P such as a substation or grid through transformers. A number of four power lines PI , P2, P3, and Pn is indicated in Fig. 3a-c.

[00062] The outputs of DC to DC converters C 1 -Cn, that are associated with the solar power convenors Sl -Sn, are selectively fed via solar power output sections into the power lines that are not used by the output lines from the wind turbines. The solar converters forming a solar power plant feed its generated power into the common power output section P via the same power lines Pl-Pn, used by the wind turbine to condition or adapt the electrical power produced by the respective solar panels.^' Thus, a reuse of the wind turbine component is achieved by sharing them with the solar power plant. Referring to Fig. 3a-c, each indicating a specific embodiment of the present subject matter, the generator includes the above-mentioned modular generators Gl, G2, G3, and Gn. Each modular generator Gl, G2, G3, and Gn is associated with a designated rectifier Rl, R2, R3, and Rn. The rectifiers convert the AC power transmitted from each of the modular generators Gl, G2, G3, and Gn to DC power in a known manner. Each rectifier Rl, R2, R3, and Rn is connected to the respective modular generator Gl , G2, G3, and Gn via a switch for separately switching the connection between the respective rectifier and the associated modular generator between ON and OFF conditions.

[00063] As shown in Fig. 3a-c, a plurality of solar power converters SI , S2, S3, and Sn are provided which are comprised by the solar power source of the integrated wind and solar power system. Each of said solar power converters is coupled to a corresponding solar power output section. That is, the plurality of solar power converters SI , S2, S3, and Sn is associated with a respective DC to DC converter CI, C2, C3, and Cn, which are optional as there are already DC to DC converters Dl, D2, D3, and Dn in the plurality of power lines Pl -Pn. These DC to DC converters may be provided to adapt the varying output voltages of each of the converters SI , S2, S3, and Sn to the predetermined DC voltage that is acceptable as input at the power lines Pl-Pn.

[00064] As further indicated in Fig. 3a-c, the plurality of power lines Pl-Pn is provided.

Each power line is provided with a DC to DC converter Dl, D2, D3, and Dn and a optional storage in the form of a DC link. The output of the above-mentioned DC to DC converters Dl, D2, D3, and Dn in each of the power lines Pl-Pn is connected to an inverter II, 12, 13, and In, which in turn are connected to a transformer Tl, T2, T3, and Tn. Each of these transformers Tl , T2, T3, and Tn of the power lines is associated with a grid in order to input AC power which is synchronized with the frequency of the grid and adapted in voltage.

[00065] As would be appreciated by a person skilled in the art, the transformers Tl, T2,

T3, and Tn can be each be associated with one single transformer when providing power to the grid (as depicted in Fig. 3a), or can be associated with individual transformers (as depicted in Fig. 3b), or can be associated with shared transformers (as depicted in Fig. 3c). Accordingly, the transformers Tl, T2, T3, and Tn can be further associated with one or more switching circuits SC, which can be configured to select any one or more power lines Pl-Pn with any output transformer. As would also be gathered, provision of such switching circuits SC and multiple transformers also account for redundancy. Furthermore, any one or more combinations of transformers can be utilized for obtaining the power output from the integrated wind and solar power system.

[00066] Each input of the power lines Pl-Pn is provided with a switch SW1 , SW2, SW3, and SWn such that the input of each power line Pl-Pn can be electrically connected to one of the outputs of the DC to DC converters CI , C2, C3, and Cn provided for the solar converters SI, S2, S3, and Sn or to each of the AC to DC converters Rl, R2, R3, and Rn provided for the modular generators Gl , G2, G3, and Gn. Consequently, each of the switches SW1, SW2, SW3, and SWn can be switched to a position where the respective of said AC to DC converters Rl, R2, R3, and Rn of the modular generators Gl, G2, G3, and Gn is connected to the input of the respective of said power lines Pl -Pn, whereas, in a second position, said switch is switched to a position where alternatively the respective of said DC to DC converters CI, C2, C3, and Cn of the solar converters SI, S2, S3, and Sn is connected to the input of the respective of said power lines Pl-Pn. In one example, Fig. 3a depicts that the switch SW1 connects the DC to DC converter CI of the solar power converter SI to the power line PI, i.e., the solar power plant uses power line PI, whereas the wind turbine use power lines P2, P3, and Pn as the switch SW2, SW3, and SW3 connects the AC to DC converters R2, R3, and Rn of the modular generators G2, G3, and Gn to the power lines P2, P3, and Pn respectively. In this example, as depicted in Fig. 3a, the AC to DC converter Rl is not connected to the modular generator Gl . Similarly, Fig. 3b depicts that the solar power plant uses the power lines PI and P2, through switches SW1 and SW2 whereas the wind turbine uses the power lines P3 and Pn through switches SW3 and SW4. Similarly, Fig. 3c depicts that the solar power plant uses the power lines PI , P2, and P3, whereas the wind turbine uses the power line Pn.

[00067] . In the embodiment shown in Fig. 3a-c, the solar farm comprises n=4 solar converters Sl-Sn, whereas the generator comprises n=4 modular generators Gl-Gn. This number is only an example and more or less modular generators Gn or solar converters Sn can be provided as long as the advantage of the present invention can be achieved.

[00068] According to the basic concept of the present embodiment, each modular generator Gn is capable of producing electric energy in the form of AC power which is converted to DC power by the associated AC to DC rectifier Rn. Moreover, each solar converter Sn is capable of producing electric power in the form of DC electric power which is adapted in voltage by the associated DC to DC converter Cn. As shown in Fig. 3a-c, the integrated wind and solar system includes a power management and control unit (PMCU). The PMCU is associated to the overall system explained above. In particular, the PMCU obtains information from a solar radiation measurement and from a wind measurement. Moreover, the PMCU performs, an output power management at the transformers Tn in view of the requirements of the connected grid.

[00069] As further input, the PMCU derives power related information of each of the solar converters Sn and of the modular generators Gn as well as information relating to the operational conditions of the converters, transformers, and inverters.

[00070] The PMCU outputs signals for operating the switches SWn. In particular, the

PMCU is arranged to separately switch the switches SW1, SW2, SW3... SWn to connect one of the modular generators Gn to the associated power line or to switch one of the solar converters Sn to said power line. Consequently, the PMCU selectively switches either one of the solar converters Sn or one of the modular generators Gn to the associated power line Pn.

[00071] Moreover, each of the wind turbines has a (not illustrated) controller configured to monitor the energy available in the wind and the solar radiation based on the operating parameters such as wind velocity and temperature are measured by appropriate sensors. The PMCU includes one or more processors and a memory coupled to the processor. The memory has one or more modules which contain the logic to retrieve the above-discussed information from the sensors to automatically trigger the activation/deactivation of the above-mentioned connections. Based on the wind energy as estimated by the PMCU, one or more generator sections Gn are switched on by the respective switch SWn and are connected to its respective power line Pn. Remaining generator sections are disconnected from the respective power lines. These disconnected power lines are then connected to the output from one or more solar converters Sn based on the available solar energy. [00072] The above control is performed by the PMCU selectively switching each of the plurality of switches SWl , SW2, SW3, and SWn to couple said one or more of generator power output sections to said associated one or more of said plurality of power lines PI, P2, P3, and Pn, so as to first process power available from said generator G to one or more of said plurality of power lines PI, P2, P3, and Pn, Further, the PMCU determines a balance capacity of said plurality of power lines PI , P2, P3, and Pn, available after utilizing power from said generator G and utilizes said balance capacity of said plurality of power lines PI, P2, P3, and Pn, by processing power from said one or more solar power output sections.

[00073] In order to achieve the above function, the PMCU can include a preloaded decision map including a correlation between wind speed and solar radiation with the expected power output from each of said one or more generator power output sections, each of said one or more solar power output sections, and said power output section P. The PMCU may periodically update automatically said preloaded decision map to an updated map capturing seasonal and site specific variations of available wind and solar energy.

[00074] According to a modification of the embodiment, the PMCU can be further configured to process said updated map to forecast power generation from the said wind and solar power system for a user defined period.

[00075] Therefore, at any time, a power line receives the power output either from the wind turbine or from one or more solar converters. Such an integration of solar generated and wind turbine generated power not only efficiently utilizes the infrastructure, but also increases the ability to provide stable power with a substantially higher degree of avai lability and predictability. Accordingly, it is the aim of the present subject matter to increase the average power yield from the wind turbine infrastructure from approximately 25% of its rated power capacity to a value which is as high as 80% of the rated power capacity. In the present subject matter, the available spaces between wind turbines are utilized for installation of a plurality of solar panels to be dynamically associated with a wind turbine of the farm. The plurality of solar panels can provide extra power of up to 50-60% of the rated power capacity of the wind turbine infrastructure to complement the power generated by the wind turbines of the wind farm. Generally, the wind and solar power energy available are seasonal and vary during a time of the day over a moth and/or a year. At major geographical locations, the seasonal variation in wind and solar energy are substantially complementary, i.e. the sum total of energy available from the sun and the wind provides a nearly uniform supply of power during the day and over the year thereby substantially minimizing the variations over a period. More importantly, the sum total of the power is more than what is available from only wind energy or only solar energy.

SPECIFIC OPERATION [00076] For explaining the operation of the system, the wind velocity at a particular time is considered to be such that the power generated by the wind turbine is 0.25X (X being the rated power output of the wind turbine) with all four generator sections being active. However, the same output power can also be realized by activating only one generator section of said modular generator. The PMCU can be configured to dynamically deactivate generator sections that are not required, e.g. G2, G3 and Gn and there associated power lines P2, P3 and Pn. The output power drawn will be 0.25X from Gl. This power can be handled by one power line, e.g. PI, which is designed for a maximum power of 0.25X. As a result, both the efficiency of the generator section and the efficiency of the power line could be maximum at the rated throughput of 0.25X.

[00077] In order to increase the power output, the power from the solar panels of the solar converters can be used if available. Consider now that the energy available from solar radiation, as estimated by the PCMU, is 0.5X. The PMCU, based on the lookup table, can trigger, e.g., switches SW2 and SW3 at the input of the power lines to connect to the DC to DC converter output lines C2 and C3, each delivering 0.25X, to two of the power lines, e.g., P2 and P3. While the maximum realizable power in this condition, e.g. 0.25X+0.5X is realized, the Pn power line stays deactivated.

[00078] When the wind velocity increases, the remaining generator sections of said modular generators and corresponding power lines are activated by the PMCU. If the available wind power increases, e.g. to 0.5X, the PMCU activates an additional generator section of said modular generator, e.g. Gn into service and connects the output from a rectifier Rn to the power line Pn. This decision is based on a preloaded decision map in the form of a lookup table or logic of the PMCU. It is preferable that such information be present in the lookup table for a faster decision process. This decision process can include the identification of the source of power being processed by each of the power lines being one of from said wind turbine and said solar power source. In one implementation, the decision map may include a correlation between wind speeds and solar radiation, and expected power output from the one or more generator sections (Gl , G2, G3, and Gn) and the solar power output sections. The decision process is performed by the PMCU including the preloaded decision map as discussed above. In this process, the PMCU may periodically update automatically the preloaded decision map to an updated map capturing seasonal and site specific variations of available wind and solar energy as explained above.

[00079] When the wind power increases further, say to 0.75X, the PMCU disconnects the power line P2 from the DC to DC converter C2. The PMCU then activates G2 and simultaneously connects the output from the rectifier R2 to the power line P2. Similarly, as the wind velocity drops, some generator sections of said modular generator and power lines can be deactivated. In case that the solar panels of said solar converter are generating power, these power lines can be chosen to be connected to the solar converter output lines to cover up for the shortfall due to the lack of available wind power. Consequently, an optimization in component usage is achieved based on the wind velocity and/or sunlight. A particular case is when the wind energy is at its peak, e.g., the power that can be generated from the wind turbine is X. In such a situation, all generator sections of said modular generator of the wind turbine will be activated and associated with the power lines while the power from the solar converters will not be used. In addition or as replacement of said control by the PMCU, the wind or solar mode of operation is user selectable whereby the source can be chosen based on the benefits of power tariff.

[00080] It is understood that the power available from wind or solar may not always be integral multiples of the individual component rating (0.25X in the above-illustrated example). In such cases, the PMCU is configured to take an intelligent decision either to use the power excess over multiple of 0.25X by connecting the unused power line or to use to the uniised power line for connecting the solar power output, based on the availability of the solar power.

[00081] In a further example, in the event that a wind turbine is down on a windy day, for mechanical reasons concerning e.g. blades, generator, nacelle or other related problems, and the total power lines associated with that wind turbine may be utilized to harness the solar power from the plurality of solar panels to it. In a further example, the solar power generated from the solar panels associated with a wind turbine may be made available for use with the other wind turbines of the wind farm. This may be advantageous, for example, in the event that a wind turbine, with which the solar panels are associated, is able to generate power close to its rated capacity or if a failure occurs in one or more of the power lines associated with a wind turbine. In the first case, the power lines will be selected as described in a previous example to be associated with all the generator sections of the wind turbine. The surplus power generated from the solar panels associated with this wind turbine can then be made available for use with the other wind turbines of the wind farm as required. In the second case, the faulty power lines of a wind turbine cannot be engaged with its associated solar panels or with its generators. The surplus power of the solar panels can then be redirected to the power line and associated with a different wind turbine having operational but unutilized power lines. The PMCU monitors the failure or reduction of power output from each wind turbine and is capable of automatically switching the solar panels from one turbine to the other.

[00082] Other examples with essentially the same principle can also be realized. For instance, in one example, the number of power lines need not be the same as the number of generator sections of said modular generator, that is, a number of n for a wind turbine. If the number of power lines provided with a wind turbine is m, where m>n, then n out of the m power lines can be selected for association with the available generator sections and/or solar converters as described above and the remaining m-n power lines can either serve as backup for power lines which may subsequently fail or to load share with the power lines already engaged with the generators or solar panels. The rating of power lines in such implementation will be appropriately chosen as X/n or below based on the desired functionality. Similarly, as in other examples, a number of solar panels and of the DC to DC solar power converters may also be different from n.

[00083] In the above embodiment, said generator G is explained as comprising a plurality of generator sections Gl, G2, G3, and Gn wherein each of said generator sections Gl, G2, G3, and Gn is coupled to a corresponding generator power output section. According to specific embodiment, each of said plurality of generator sections Gl , G2, G3, and Gn is formed by at least one pair of diametrically opposite stators including corresponding windings, and outputs AC power to said one or more generator power output section.

[00084] In the above embodiment, said solar power source comprises a plurality of solar power converters S I , S2, S3, and Sn, wherein each of said solar power converters is coupled to a corresponding solar power output section. In a specific embodiment, each of said plurality of solar converters S I , S2, S3, and Sn comprise one or more solar converter sections which are selectively connected in parallel or in series to each other in order to provide a required DC voltage.

[00085] In the above embodiment, said controller such as the PMCU is configured to selectively switch each of said plurality of switches. In a specific embodiment, said controller such as the PMCU, is further configured to detect one or more dysfunctional generator power output sections and accordingly take in circuit one or more functional generator power output sections based on said updated map.

[00086] In the above embodiment, the selective switching of said each of plurality of switches SW1, SW2, SW3, and SWn is performed to couple said one or more of generator power output sections to said associated one or more of said plurality of power lines PI, P2, P3, and Pn, so as to first process power available from said generator G to one or more of said plurality of power lines PI , P2, P3, and Pn. Further, a balance capacity of said plurality of power lines PI , P2, P3, and Pn available after utilizing power from said generator G is determined. In the above embodiment, the balance capacity of said plurality of power lines PI , P2, P3, and Pn by processing power from said one or more solar power output sections is utilized and the power output of the solar power output sections not connected is not output to the common power output section P. According to a specific embodiment, the power available from the solar power output sections not connected to said common power output section can be utilized for alternative or optional purposes, such as supply of energy to a storage means for later use or application which required DC output such as aluminium electrolysis. However, the use of the energy of non- connected solar converters is not essential for the invention and it is within the scope of the claims if the power output of solar converters which are not connected is not used. In such a case, intermediate DC power can be obtained directly from one or more solar power converters SI, S2,

S3, and Sn as shown in Fig. 3c, as per one embodiment of the present subject matter. [00087] The above embodiments or modifications are not restrictive and are not intended as limitation of the scope of the claims. The different aspects and embodiments of the present subject matter are further provided below.

Claims

I/We claim:

1. An integrated wind and solar power system, comprising:

a wind turbine (W) having a generator (G), wherein said generator (G) is coupled to one or more generator power output sections;

a solar power source having one or more solar power output sections;

a plurality of power lines (PI, P2, P3, and Pn.) coupled to a common power output section (P) for feeding power to an electric power grid;

a plurality of switches (SW1, SW2, SW3, and SWn), each of the plurality of switches having a first input associated with one of said generator power output sections, a second input associated with one of said solar power output sections, and an output associated with one of said plurality of power lines (PI, P2, P3, and Pn); and

a controller (PMCU) configured to selectively switch each of said plurality of switches (SW1, SW2, SW3, and SWn) to one of said associated first input and said associated second input, based on any one or more of input wind power related information, input solar energy related information, and power output information.

2. The integrated wind and solar power system according to claim 1, wherein said generator (G) comprises a plurality of generator sections (Gl , G2, G3, and Gn), and wherein each of said generator sections (Gl , G2, G3, and Gn) is coupled to a corresponding generator power output section.

3. The integrated wind and solar power system according to one of claims 1-2, wherein said solar power source comprises a plurality of solar power converters (SI, S2, S3, and Sn), and wherein each of said solar power converters is coupled to a corresponding solar power output section.

4. The integrated wind and solar power system according to one of claims 1-3, wherein said controller (PMCU) is further configured to identify the source of power being processed by each of said power lines being one of from said wind turbine and said solar power source.

5. The integrated wind and solar power system according to one of claims 1-4, wherein said controller (PMCU) includes a preloaded decision map including a correlation wind speed and solar radiation with the expected power output from each of said one or more generator power output sections, each of said one or more solar power output sections, and said power output section (P), and wherein said controller (PMCU) periodically updates automatically said preloaded decision map to an updated map capturing seasonal and site specific variations of available wind and solar energy.

6. The integrated wind and solar power system according to claim 5, wherein said controller (PMCU) is further configured to process said updated map to forecast power generation from the said wind and solar power system for a user defined period.

7. The integrated wind and solar power system according to one of claims 1-6, wherein said controller (PMCU) is configured to perform steps comprising:

selectively switching said each of plurality of switches (SWl , SW2, SW3, and SWn) to couple said one or more of generator power output sections to said associated one or more of said plurality of power lines (PI, P2, P3, and Pn), so as to first process power available from said generator (G) to one or more of said plurality of power lines (PI, P2, P3, and Pn);

determining a balance capacity of said plurality of power lines (PI , P2, P3, and Pn) available after utilizing power from said generator (G); and

utilizing said balance capacity of said plurality of power lines (PI, P2, P3, and Pn) by processing power from said one or more solar power output sections.

8. The integrated wind and solar power system according to one of claims 5-6, wherein said controller (PMCU) is further configured to detect one or more dysfunctional generator power output sections and accordingly take in circuit one or more functional generator power output sections based on said updated map.

9. The integrated wind and solar power system according to one of claims 1-8, wherein said controller (PMCU) is configured to monitor a functional status of said power lines (PI ,

P2, P3, and Pn), and to switchover to functional power lines when one of said power lines (PI, P2, P3, and Pn) is detected to be dysfunctional.

10. The integrated wind and solar power system according to one of claims 1 -9, further including at least one DC to DC converter (Dl, D2, D3, and Dn), at least one inverter (II, 12, 13, and In), and at least one transformer (Tl , T2, T3, and Tn).

1 1. The integrated wind and solar power system according to one of claims 1 -10, wherein a maximum rated power throughput of elements forming said power line (PI , P2, P3, and Pn) is adapted to a maximum power output of said associated generator output section.

12. The integrated wind and solar power system according to one of claims 1-1 1, wherein combined rated power capacity of said plurality of power lines (PI, P2, P3, and Pn) is at least equal to rated capacity of said wind turbine (W).

13. The integrated wind and solar power system according to one of claims 1-12, wherein said wind and solar power system further includes additional one or more power lines to provide redundancy and a buffer capacity.

14. The integrated wind and solar power system according to claim 2, wherein each of said plurality of generator sections (Gl, G2, G3, and Gn) is formed by at least one pair of diametrically opposite stators including corresponding windings, and outputs AC power to said one or more generator power output section.

15. The integrated wind and solar power system according to one of claims 1-14, wherein said generator power output section is coupled to a rectifier, said rectifier providing DC power to said power line (PI, P2, P3, and Pn).

16. The integrated wind and solar power system according to one of claims 3-15, wherein each of said plurality of solar converters (SI , S2, S3, and Sn) comprise one or more solar converter sections which are selectively connected in parallel or in series to each other in order to provide a required DC voltage.

17. The integrated wind and solar power system according to one of claims 3-16, wherein each of said solar converters (S I , S2, S3, and Sn) is connected to said associated plurality of switches (SW1, SW2, SW3, and SWn) via a DC-DC converter (CI , C2, C3, and Cn) for adapting said voltage to a predetermined input requirement of said inverter (II, 12, 13, and In).

18. The integrated wind and solar power system according to one of claims 1-17, wherein said controller (PMCU) is configured, based on a user defined input, to couple a combination of said one or more of generator power output sections and said one or more solar power output sections to optimise the cost of power to said user based on a tariff structure.

19. The integrated wind and solar power system according to one of claims 1-18, wherein said wind and solar power system includes any other power sources of equivalent capacity in addition or as replacement of one or more solar converters (S I, S2, S3, and Sn).

20. The integrated wind and solar power system according to claim 19, wherein said any other power sources include any one or more of renewable energy sources.

21. A method of operating an integrated wind and solar power system, the method comprising: obtaining periodically information relating to input wind power, input solar energy, and power output of said wind and solar power system, said wind and solar system comprising a generator (G), wherein said generator (G) includes one or more generator power output sections, and each of said one or more generator power output sections is switchably coupled to a power line (PI, P2, P3, and Pn); based on said information relating to input wind power, input solar energy, and power output of said wind and solar system, coupling said one or more generator power output sections by selectively switching to one or more said power lines (PI , P2, P3, and Pn), and coupling one or more solar power output sections to one or more power lines not coupled to said one or more generator power output sections.

22. The method of operating an integrated wind and solar power system according to claim 21, wherein said power output information of said wind and solar system includes information related to power output from said plurality of generator power output sections, from said plurality of solar power output sections, and from said plurality of power lines.