CN116111631A

CN116111631A - DC combined storage networking hydroelectric generation system

Info

Publication number: CN116111631A
Application number: CN202111333750.7A
Authority: CN
Inventors: 谢俊; 熊俞超; 王琳; 沈虹
Original assignee: Individual
Current assignee: Three Gorges Power Co ltd
Priority date: 2021-11-11
Filing date: 2021-11-11
Publication date: 2023-05-12

Abstract

The embodiment of the invention discloses a direct current combined storage networking hydroelectric generation system, which comprises a hydroelectric generation device, an energy storage device and an inversion device, wherein the hydroelectric generation device comprises a phase-change generator and a rectification matrix, the induction alternating current output by the phase-change generator is rectified into a constant-voltage direct current source through the rectification matrix, the constant-voltage direct current source and the energy storage device are connected in parallel on a direct current busbar, one end of the inversion device is connected with the direct current busbar, and the other end of the inversion device is connected with a power grid. The induction alternating current generated by the phase-change generator of the hydroelectric power generation device is rectified into a constant-voltage pulse direct current source through the rectifying matrix, the constant-voltage direct current source and the energy storage device are connected in parallel to the direct current busbar, the constant-voltage pulse direct current source has strong dynamic balancing capability, and then high-quality direct current can be output through the energy storage voltage stabilization to form an energy balance body matched with grid-connected electric quantity of the power grid through the inversion device, so that the problem of water energy resource waste caused by fluctuation of the power grid in the prior art is solved, the energy utilization rate is improved, and the overall cost is saved.

Description

DC combined storage networking hydroelectric generation system

Technical Field

The invention relates to the technical field of hydroelectric power generation systems, in particular to a direct current combined storage networking hydroelectric power generation system.

Background

The hydroelectric power generation is a renewable energy source, has small impact on the environment, has the power generation efficiency of more than 90 percent, has low power generation cost, quick power generation starting, can finish power generation within a few minutes, is easy to adjust and has low cost of unit output power. Besides providing inexpensive electricity, the utility model has the advantages of controlling flood flooding, providing irrigation water, improving river shipping, improving traffic, electricity supply and economy in the area in related engineering, and particularly can be used for developing tourism and aquaculture.

However, the traditional hydroelectric generation is to directly generate alternating current according to the existing alternating current power grid system and then adjust the alternating current to enter the grid through a transformer. The rotation speed of the water turbine has strict requirements, and the generated sine wave alternating current must meet the frequency of 50 Hz or 60 Hz. When the grid-connected electric quantity of the power grid changes, certain water energy is inevitably wasted in the process of fluctuation of the power grid, and the water energy utilization rate is affected.

Disclosure of Invention

In view of the above, the embodiment of the invention provides a direct current combined storage networking hydroelectric power generation system, which is characterized in that induction alternating current generated by a phase-change generator of a hydroelectric power generation device is rectified into a constant voltage direct current source through a rectification matrix, the constant voltage direct current source and an energy storage device are linked together through direct current combined storage, so that the system has stronger dynamic balancing capability, further, an energy balance body matched with grid-connected electric quantity of a power grid can be output through a power electronic inversion device, and the grid connection is performed by utilizing the immediate response advantage of the power electronic device, so that the problem of water energy resource waste caused by power grid fluctuation in the prior art is solved, and the beneficial effects of improving the energy utilization rate and saving the whole cost are achieved.

In order to achieve the above object, the present invention provides a direct current linked storage networking hydro-power generation system, comprising:

the hydroelectric generation device comprises a phase-change generator and a rectification matrix connected with the phase-change motor, and induction alternating current output by the phase-change generator is rectified into a constant-voltage direct current source through the rectification matrix;

the energy storage device is connected with the constant-voltage direct-current source in parallel and is connected to the direct-current busbar;

and one end of the inversion device is connected with the direct current busbar, and the other end of the inversion device is connected with a power grid.

Further, a plurality of phase coils are arranged in the phase-change generator, each phase coil is externally connected with a rectifier, direct current output by each rectifier is used as an independent direct current power supply, and the direct current power supplies are arranged to form the rectification matrix.

Further, each direct current power supply is connected in series in turn.

Further, each direct current power supply is connected in series-parallel connection.

Further, the energy storage device comprises a plurality of battery packs, and the battery packs are connected in parallel.

Further, the battery pack includes a plurality of batteries.

Further, the inverter device includes at least one inverter unit, each of which is connected in parallel.

Further, the inverter unit includes an inverter and a transformer, and the inverter is connected in series with the transformer.

Further, the direct current busbar comprises an input end and an output end, the constant voltage direct current source and the energy storage device are both connected to the input end, and the inversion device is connected to the output end.

Further, the hydroelectric generation device further comprises a water turbine, and an output shaft of the water turbine is connected with a rotor of the phase-change generator.

According to the embodiment of the invention, the following advantages are achieved:

the invention rectifies the induction alternating current generated by the phase-change generator of the hydroelectric generation device into a constant-voltage direct current source through the rectification matrix, the constant-voltage direct current source and the energy storage device are connected in parallel on the direct current busbar, the constant-voltage direct current source has stronger dynamic balancing capability, and the energy balance body which is matched with the grid-connected electric quantity can be output through the inversion device by connecting the direct current busbar with one end of the inversion device, so that the problem of water energy resource waste caused by the fluctuation of the power grid in the prior art is solved, and the beneficial effects of improving the energy utilization rate and saving the whole cost are achieved.

Specifically, a plurality of phase coils are arranged in the phase-change generator, each phase coil is externally connected with a rectifier, direct current output by each rectifier is used as an independent direct current power supply, the direct current rectified by the rectification matrix is directly connected in parallel through a direct current busbar and an energy storage device by utilizing the characteristic that the direct current can be split and combined, and then a direct current combined storage type double-source power station is constructed.

In addition, the invention has the advantages that the frequency is not considered, so the voltage is stabilized through direct current combined storage, the inversion efficiency can be kept unchanged in the grid-connected process, and particularly, in the parallel operation process of a plurality of inversion units, all inverters share one direct current busbar and belong to a homologous state, so that the phase loss is saved, the energy utilization rate is further improved, and the overall cost is saved.

Furthermore, because the energy storage device has a natural buffering effect, the power electronic inverter has natural timely response capability, the power generation device has natural frequency modulation and peak regulation capability, and the power grid stability is maintained to play a positive role.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below. It will be apparent to those of ordinary skill in the art that the drawings in the following description are exemplary only and that other implementations can be obtained from the extensions of the drawings provided without inventive effort.

The structures, proportions, sizes, etc. shown in the present specification are shown only for the purposes of illustration and description, and are not intended to limit the scope of the invention, which is defined by the claims, so that any structural modifications, changes in proportions, or adjustments of sizes, which do not affect the efficacy or the achievement of the present invention, should fall within the ambit of the technical disclosure. Besides the phase-change motor, the DC networking mode also supports the traditional generator set.

Fig. 1 is a schematic diagram of a direct current combined storage networking hydroelectric generation system according to an embodiment of the present invention;

FIG. 2 is an electrical diagram of a variable phase generator according to another embodiment of the present invention;

FIG. 3 is a schematic diagram of a rectifier according to another embodiment of the present invention;

fig. 4 is a schematic diagram of a series connection structure of each dc power supply according to another embodiment of the present invention;

fig. 5 is a schematic diagram of a series-parallel connection structure of each dc power supply according to another embodiment of the present invention;

fig. 6 is a schematic diagram of a series-parallel connection structure of each dc power supply according to another embodiment of the present invention;

fig. 7 is a schematic structural diagram of an energy storage device according to another embodiment of the present invention.

In the figure:

10. a hydroelectric power generation device; 11. a water turbine; 12. a phase-change generator; 13. a rectification matrix; 3. a power grid; 22. an energy storage device; 221. a battery pack; 2211. a battery; 23. an inversion unit; 231. a step-up transformer; 232. an inverter; 24. a direct current busbar; 130. a phase coil; 131. a rectifier; 132. a DC power supply.

Detailed Description

Other advantages and advantages of the present invention will become apparent to those skilled in the art from the following detailed description, which, by way of illustration, is to be read in connection with certain specific embodiments, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

Unless a direction is defined separately, the directions of up, down, left, right, transverse, vertical, etc. referred to herein are all based on the directions of up, down, left, right, transverse, vertical, etc. as shown in fig. 1 of the embodiment of the present application, and if the specific gesture changes, the directional indication changes accordingly. The terms "plurality" and "a plurality" as used herein and throughout the description, do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. Furthermore, in various embodiments of the present disclosure, the same or similar reference numerals denote the same or similar components.

In the present invention, unless explicitly stated and defined otherwise, the term "connected" is generally understood to mean electrically connected, unless explicitly stated otherwise. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

In addition, the technical solutions of the embodiments of the present invention may be combined with each other, but it is necessary to be based on the fact that those skilled in the art can implement the technical solutions, and when the technical solutions are contradictory or cannot be implemented, the combination of the technical solutions should be considered as not existing, and not falling within the scope of the claimed invention.

Example 1

The present embodiment provides a direct current combined storage networking hydroelectric power generation system, which is combined with a structural diagram as shown in fig. 1, and includes: the hydraulic power generation device 10, the energy storage device 22 and the inversion device, wherein the hydraulic power generation device 10 comprises a water turbine 11, a phase-change generator 12 and a rectifying matrix 13, and an output shaft of the water turbine 11 is connected with a rotor of the phase-change generator 12; the induced ac power output by the phase-change generator 12 is rectified by the rectifying matrix 13 into a constant voltage dc power source, which is connected in parallel with the energy storage device 22 to the dc busbar 24, and one end (dc end) of the inverter device is connected to the dc busbar 24, and the other end (ac end) is connected to the power grid 3.

It should be noted that, the rectifying matrix in this embodiment is a control system dedicated to the phase-change generator, including a rectifier and a switching switch, and is also applicable to a conventional generator under the same conditions. The switching switch controls the connection and disconnection of the corresponding circuit, and the rectification matrix functions to rectify the induced alternating current output by the phase-change generator 12 into a constant voltage direct current source. Furthermore, the inverter in this embodiment converts the dc power from the dc busbar into ac power and supplies the ac power to the power grid through the step-up transformer; next, the dc busbar 24 includes an input terminal and an output terminal, and the constant voltage dc source and the energy storage device are both connected to the input terminal, and the inverter device is connected to the output terminal. In addition, in the embodiment, the power supply of the hydraulic power generation device is directly fluidized, the constant-voltage direct-current source and the energy storage module which are rectified and output are connected in parallel to be connected into a direct-current network, no power conversion is performed, the self characteristics of direct current are fully utilized to construct a multi-source balance state, the stability of the system is improved, and the problem of high regulation and control difficulty is solved. Specifically, according to the change of the electric quantity demand quantity of grid connection, the direct current networking unit (an energy storage device and an inversion device) and the hydroelectric generation device are connected in parallel, and under the control of the grid connection EMS energy management system, the two are managed and linked, the whole control difficulty is greatly reduced, the stability of the power-assisted hydroelectric power generation device can be improved, and meanwhile, the power-assisted hydroelectric power generation device can play a positive role in flood control, disaster relief and flood discharge in flood season.

By means of the technical scheme, the induction alternating current generated by the phase-change generator of the hydroelectric generation device is rectified into a constant-voltage direct current source through the rectifying matrix, the constant-voltage direct current source and the energy storage device are connected in parallel to the direct current busbar, the constant-voltage direct current source has strong dynamic balancing capability, the direct current busbar is connected with one end of the inversion device, and then the energy balance body matched with grid-connected electric quantity of the power grid can be output through the inversion device, so that the problem of water energy resource waste caused by power grid fluctuation in the prior art is solved, the energy utilization rate is improved, and the overall cost is saved.

As a preferred embodiment, the inverter device in this embodiment preferably includes, but is not limited to, three inverter units 23, and may also be 2, 4, 6, 8 or more inverter units according to practical situations, and each inverter unit 23 is connected to the dc busbar 24 in parallel. Further, the inverter unit 23 includes an inverter 232 and a transformer 231, and the inverter 232 is connected in series with the transformer 231.

It should be noted that, in this embodiment, the direct current input of the transformer comes from the direct current busbar, which has the greatest advantage compared with the alternating current in that the frequency is not considered, and the voltage is stabilized by the energy storage device, so that the inversion efficiency can be kept unchanged in the grid-connected process, especially in the parallel operation process of multiple groups of inverters, since all the inverters share one direct current busbar, they belong to the homologous state, and not only the phase loss can be saved, but also the significance of direct current combined storage is achieved, thereby being beneficial to achieving the beneficial effects of improving the energy utilization rate and saving the overall cost. .

Example two

In this embodiment, as a preferred embodiment, referring to fig. 2 and 3, the phase-change motor 12 in this embodiment is a fully coupled symmetrical structure, and includes a rotor, a stator, and a plurality of phase coils 130, wherein each phase coil 130 is connected to a rectifier 131, and the rectifier 131 rectifies the alternating induction current to a direct current power source 132. In addition, the phase-change motor 12 in the present embodiment further includes a low-frequency drive circuit, a driver main power circuit, and a switching switch (not shown). As shown in fig. 3, the rectifier 131 in the present embodiment includes diodes T1, T2, T3, T4. It should be noted that, in connection with the dc power supply 132 shown in fig. 4-6, which is a representative symbol of the output power of the rectifier 231, each dc power supply performs a series-parallel connection like a battery to construct a required dc voltage. The direct current output by each rectifier 131 in this embodiment is used as an independent direct current power supply 132, and the direct current power supplies are arranged to form a direct current power supply group. Further, the rectifying matrix 13 includes a dc power supply group and a matrix switching controller (switching switch of each path), and under the condition of different rotation speeds, the matrix switching controller controls the connection mode of each dc power supply to obtain output power at different rotation speeds.

Specifically, the structure of the rectification matrix constructed by each of the dc power sources 132 shown in fig. 4 to 6 is schematically shown. The phase-change generator of the embodiment takes an 8-pole 4-phase dipole-bit motor as an example, wherein each phase coil is connected with a rectifier, direct current output by each rectifier 131 is used as an independent direct current power supply 132, and each direct current power supply 132 is subjected to series-parallel combination by switching through an array-changing controller (not shown), so as to obtain constant-voltage direct current sources at different rotating speeds. Each direct current power supply is connected in series in sequence.

Further, as a specific embodiment, as shown in fig. 4, when the rotation speed is small, the array switching controller connects each of the dc power sources 132 in series, that is, rectifies each of the phase coils and connects them in series, so as to obtain the dc high voltage required for energy storage. For example: if the voltage of the phase coils of the generator is about 100 volts, 8 phase coils are rectified and then connected in series, so that 800 volts of direct current voltage can be obtained, and the energy storage direct current combined storage system can be dealt with.

As a specific embodiment, as shown in fig. 5, when the rotation speed is moderate, the required dc voltage is obtained by 4 series 2 and phase change. For example, the phase voltage is 200V, the direct current voltage of the four strings is still 800V, and the two channels are connected in parallel to obtain doubled power, so that the direct current combined storage system is effectively applied.

In addition, as shown in fig. 6, when the motor enters the high-speed stage, the motor speed is high, the phase voltage may reach 400 v, and at this time, the motor is converted again, and 4 times of output dc power is obtained through 2 strings of 4 parallel phase changes.

It should be noted that, the rectification matrix in this embodiment has the greatest advantage of "physical isolation", compared with the traditional expensive DC/DC module, the cost is less than 20%, the reliability is improved by an order of magnitude, especially the safety of energy storage is greatly improved, thereby being beneficial to improving the energy utilization rate and saving the overall cost.

Example III

In this embodiment, as a preferred embodiment, as shown in fig. 7, the energy storage device 22 in this embodiment is formed by combining a plurality of parallel battery packs 221, and further, each battery pack 221 is formed by connecting batteries 2211 in series.

It should be noted that, the battery in this embodiment is preferably a chemical battery, a plurality of batteries are connected in series to form a battery pack, and a plurality of battery packs are connected in parallel to form an energy storage module, where the energy storage device includes an energy storage module, and the energy storage module is a multi-channel matrix battery system based on a free module that is independently developed by the unit, so that redundant description is omitted herein, and the battery type, the number of batteries, the connection mode, and the like are selected according to the actual situation. The energy storage device is connected with the hydroelectric power generation device in a power generation way, so that peak clipping, valley filling and load compensation are realized, and the energy storage power station for improving the electric energy quality application has to be easily combined in a multi-mode manner, so that larger working voltage and working current are met, and the safety and reliability are ensured.

While the invention has been described in detail in the foregoing general description and specific examples, it will be apparent to those skilled in the art that modifications and improvements can be made thereto. Accordingly, such modifications or improvements may be made without departing from the spirit of the invention and are intended to be within the scope of the invention as claimed.

Claims

1. A direct current coupled storage networking hydro-power generation system, comprising:

2. The direct current networked hydro-power generation system of claim 1, wherein: the phase-change generator is internally provided with a plurality of phase coils, each phase coil is externally connected with a rectifier, direct current output by each rectifier is used as an independent direct current power supply, and the direct current power supplies are arranged to form the rectification matrix.

3. The direct current networked hydro-power generation system of claim 2, wherein: each direct current power supply is connected in series in sequence.

4. The direct current networked hydro-power generation system of claim 2, wherein: and each direct current power supply is connected in series-parallel connection.

5. The direct current networked hydro-power generation system of claim 1, wherein: the energy storage device comprises a plurality of battery packs, and the battery packs are connected in parallel.

6. The direct current networked hydro-power generation system of claim 5, wherein: the battery pack includes a plurality of batteries, and a plurality of the batteries are connected in series.

7. The direct current networked hydro-power generation system of claim 1, wherein: the inverter device comprises at least one inverter unit, and each inverter unit is connected in parallel.

8. The direct current networked hydro-power generation system of claim 7 wherein: the inverter unit comprises an inverter and a transformer, wherein the inverter is connected with the transformer in series, the inverter is connected with the direct current busbar, and the transformer is connected with the power grid.

9. The direct current networked hydro-power generation system of claim 1, wherein: the direct current busbar comprises an input end and an output end, the constant voltage direct current source and the energy storage device are both connected to the input end, and the inversion device is connected to the output end.

10. The direct current networked hydro-power generation system of claim 1, wherein: the hydroelectric generation device further comprises a water turbine, and an output shaft of the water turbine is connected with a rotor of the phase-change generator.