FR2981218A1 - Method for supplying power to inverters in e.g. electricity production installation, involves selectively feeding supply in accordance with electric parameter by simple commutation of feeding attachment between installation and inverters - Google Patents

Abstract

The method involves providing an electric power generation device e.g. photovoltaic panel, and measuring an electric parameter that is representative of electric power produced by an electricity production installation (2). Power supply is selectively fed to one inverter (12) or a set of inverters from the electricity production installation in accordance with the electric parameter by simple commutation of a feeding attachment (4) interposed among the electricity production installation and the inverters. Independent claims are also included for the following: (1) a feeding attachment (2) an electrical installation.

Description

Method and power supply device for supplying inverters, and electrical installation comprising such a device.

FIELD OF THE INVENTION The present invention relates to methods and power devices for powering inverters, and to electrical installations comprising such devices.

More particularly, the invention relates to a power supply method for supplying a plurality of inverters from an electricity generation installation comprising at least one electrical energy generation device, this electrical energy generation device. for example: a photovoltaic installation comprising one or more photovoltaic panel batteries, a wind turbine installation comprising one or more wind turbines, a terrestrial or maritime hydroelectric installation comprising one or more generators, etc. BACKGROUND OF THE INVENTION In the known methods of this type, each electric power generation device of the electrical generation plant is individually connected to an inverter, which is sized to absorb the maximum power of the generating device. electric energy. When the electric power device operates at very low power, the corresponding inverter can not operate and the electrical energy produced is simply lost. In addition, when the electric power device operates at a low power, sufficient to start the inverter but small compared to the capacity of the inverter, the corresponding inverter operates with a very poor performance, where again a significant loss of electrical energy. To overcome this drawback, attempts have been made to produce parallel-connected inverter assemblies comprising a master inverter and slave inverters which are selectively started by the master inverter as a function of the power to be corrugated. An example of such a system is described in WO-A-2009/050015. Systems of this type, however, have the drawback of using specific and generally expensive inverters. OBJECTS OF THE INVENTION The present invention is intended to overcome these disadvantages. For this purpose, according to the invention, a method of the kind in question comprises at least the following stages (possibly repeated continuously): (a) a measuring step in which at least one electrical parameter representative of a power is measured electrical power produced by the power generation plant, (b) and a power supply step in which, depending on said electrical parameter, selectively powering either one inverter or several inverters of the plurality of inverters from said electrical installation, by simple switching of a supply device interposed between the electrical installation and the inverters. Thanks to these arrangements, it is possible either to concentrate the power produced by the power generation installation on a single inverter when the power produced by said electrical installation is low, which makes it possible to operate this inverter with the best It is possible to distribute the power produced by the power generation plant on several inverters, when this power exceeds a certain threshold, which makes it possible to operate each inverter with the best possible efficiency.

This optimized management of the inverters is obtained without having to interact especially with the inverters, and without having to necessarily make them interact with each other, which avoids having to necessarily use specific inverters and which also makes it possible to apply the invention to the inverters. existing electrical installations, regardless of the inverters already installed. In various embodiments of this process, one or more of the following arrangements may also be used (possibly used independently of one another and independently of the above-mentioned provisions): production of electricity comprises several devices for generating electrical energy, during measurement step (a), several electrical parameters representative of the electrical powers produced by the devices for generating electrical energy are measured, and according to said electrical parameters, the electrical powers produced by the electrical energy generation devices are distributed selectively to one or more of the inverters during step (b); during step (b), the electrical powers produced by several devices for generating electrical energy are grouped together on the same inverter, as long as the electric powers produced by these electric energy generating devices are less than one certain first threshold, and the electric powers produced by these electrical energy generation devices, respectively, are sent to several different inverters, when the electric powers produced by these electric energy generating devices are greater than a second threshold (possibly equal to at the first threshold): it will be noted that in this way, if one of the electrical energy generating devices has operating problems, these problems only disturb the inverter (s) to which it is connected, but not the neighboring inverters. when the inverters operate with sufficient load.

Furthermore, the invention also relates to a power supply device for supplying a plurality of inverters from an electricity generation installation comprising at least one electrical energy generation device, this power supply device comprising: - at least one power input intended to be connected to said electrical energy generating device for receiving the electrical energy produced by said electrical energy generating device, a plurality of power outputs intended to be respectively connected to the inverters of said plurality of inverters for supplying said inverters, a control device adapted for, as a function of at least one electrical parameter representative of an electric power produced by the power generation plant, selectively powering by switching , either a power output or several power outputs from said at least one power input. It should be noted that the electrical parameter in question can result from a measurement made by the power supply device, or from a measurement received by this power supply device, and coming for example from the device for generating electrical energy. In various embodiments of the feed device according to the invention, one or more of the following arrangements may also be used (possibly used independently of one another and independently of the aforesaid arrangements). ): the supply device comprises at least one data input adapted to receive said at least one electrical parameter; the power supply device comprises a plurality of power inputs intended to respectively receive the electrical energy produced by several electrical energy generation devices, and the control device is adapted to, as a function of electrical parameters representative of available electrical powers. at each power input, allocate the available electrical powers to the different power inputs selectively on one or more power outputs; the control device is adapted to group together on the same power output, the available electrical powers at several power inputs, as long as the said electric powers available at these power inputs are below a certain first threshold, and to send the electric powers available at these power inputs respectively to a plurality of different power outputs, when said available electrical powers at said power inputs are greater than a second threshold (possibly equal to the first threshold); the control device comprises an electronic central unit controlling switching devices which each connect at least one device for generating electrical energy to an inverter and which are interconnected by branch lines, these switching devices being adapted each for selectively opening or closing a power output and opening or closing at least one branch line. The subject of the invention is also an electrical installation comprising: a plurality of inverters, an electricity production installation comprising at least one electrical energy generation device, a power supply device as defined above, wherein said at least one power input is connected to said electrical power generating device for receiving electrical energy produced by said electric power generating device, and whose power outputs are respectively connected to the inverters of said plurality. Inverters for supplying said inverters. BRIEF DESCRIPTION OF THE DRAWINGS Other features and advantages of the invention will become apparent from the following description of one of its embodiments, given by way of non-limiting example, with reference to the accompanying drawings. In the drawings: FIG. 1 is a schematic view of an electrical installation according to one embodiment of the invention, and FIGS. 2 to 6 are views similar to FIG. 1, showing several operating configurations of the Electrical installation of Figure 1. DESCRIPTION DETAILED In the different figures, the same references 30 designate identical or similar elements. FIG. 1 represents a plant 1 comprising: a power generation installation 2 which comprises at least one, and preferably several, electric power generation devices 3 (four in number in the example considered here and referenced individually G1-G4), each of these devices for generating electrical energy 3 can be for example a set of photovoltaic panels, or any other device for generating electrical energy (wind, hydroelectric turbine or other) producing a direct current or any other current other than sinusoidal alternating; a plurality of inverters 12 (here also four and referenced 11-14) fed by the electric power generation devices 3 and themselves supplying an electrical network 13 (R); and a supply device 4 interposed between the electrical energy generating devices 3 and the inverters 12. The supply device 4, for its part, comprises: a central unit 5 (CPU), for example a microcontroller or other, which may comprise: - optionally one or more digital or analog data inputs 6, respectively connected to the devices for generating electrical energy 3 to receive from each of them an electrical power value P1, P2, 25 P3, P4 produced individually by each of these electric power generation devices G1-G4, or to receive from said devices any other electrical parameter representative of the electric power produced, - one or more control outputs 7; switching devices 8 (C1-C4) each individually controlled by the control output (s) 7 of the control device 5; power inputs 9 each connecting one of the electric power generating devices 3 to one of the switching devices 8; - Bypass lines 10 respectively connecting the switching devices 8 to each other (more precisely, these branch lines 10 connect respectively the switching devices C1 and C2, C2 and C3, C3 and C4, and power outputs 11 respectively connecting each switching device 8 to one of the inverters 12. The switching devices 8 are each adapted to connect the corresponding power input 9, either to the corresponding power output 11, or to one of the These switching devices can each consist, for example, in their simplest version, in switches controlled by the central unit 5 and provided respectively at the output 11 corresponding to the switching devices 8 considered and at the level of which each branch line 10 connected to said switching device 8 considered (at least s a branch line switch 10 by switching device 8). The aforementioned switching devices 8 may however be made by any other known means. The installation 1 which has just been described operates as follows. First configuration (FIG. 2) As represented in FIG. 2, when the electric powers P1, P2, P3, P4 produced by the various electrical energy generating devices G1-G4 are low, for example by the time covered when These are sets of photovoltaic panels, the central unit 5 controls the switching devices 8 so that the electric powers produced by each of the electric power generation devices G1-G4 are grouped together on the output 11 corresponding to only one of the inverters 12, for example the inverter I1. In this way, this inverter I1 is supplied with the maximum possible power, and thus operates with the best possible electrical efficiency. In this configuration, all the branch lines 10 are closed as is the output 11 to the inverter II, while the outputs 11 corresponding to the inverters 12-14 are open. The central unit 5 adopts this first configuration, for example when the sum P1 + P2 + P3 + P4 of the powers produced by the different devices for generating electrical energy G1-G4, is less than a first predetermined threshold Si, for example 10 kW in a particular example. On the other hand, when the sum of the powers P1 + P2 + P3 + P4 becomes greater than a second predetermined threshold S2, for example 11 kW in a particular example, the central unit 5 switches the switching devices 8 so as to adapt a second configuration, described below. Second configuration (FIG. 3) In the second configuration shown in FIG. 3, the powers P1, P2 produced respectively by the electrical energy generation devices G1, G2 are grouped together on the inverter II, while the powers P3, P4 produced respectively by the electric power generation devices G3, G4 are grouped together on the inverter 13, the inverters 12 and 14 remaining unused. In this second configuration, the branch line 10 between the switching devices C2, C3 is open, as are the outputs 11 to the inverters 12, 14. From this second configuration, if the sum of the powers P1 + P2 + P3 + P4 again becomes lower than Si, then the central unit 5 switches the switching device C3 back to the first configuration described above. On the other hand, from the second configuration: if P1 + P2> S2 and P3 + P4 <S2, then the central unit 5 switches the switching devices 8 to adopt the third configuration which will be described below, if P1 + P2 <S2 and P3 + P4> S2, the central unit 5 switches the switching devices 8 to adopt the fourth configuration which will be described hereinafter, and if P1 + P2> S2 and P3 + P4> S2, then the central unit 5 switches the switching devices 8 to adopt the fifth configuration which will be described below. Third configuration (FIG. 4) In this third configuration, the central unit 5 switches the switching devices 8 so that: all the electrical power P1 produced by the electrical energy generating device G1 is transmitted to the Inverter II, all the electrical power P2 produced by the electrical energy generation device G2 is transmitted to the inverter 12, and the electrical powers P3 and P4 produced by the electrical energy generation devices G3 and G4. all inverts 13, the inverter 14 remaining inactive. In this configuration, the branch lines 10 between the switching devices C1, C2 and between the switching devices C2, C3 are open, as is the output 11 between the switching device C4 and the inverter 14. From of this third configuration, the central unit 5 can switch the switching devices 8: - in the second configuration described above if P1 + P2 <Si, - and in the fifth configuration, if P1 + P2> S1 and P3 + P4> S2.

Fourth configuration (FIG. 5) In the fourth configuration, the central unit 5 switches the switching devices 8 so that: the powers P1, P2 produced by the electrical energy generation devices G1, G2 are totally grouped together on the inverter II, the inverter 12 remains inactive, the power P3 produced by the electrical energy generating device G3 is transferred in its entirety to the inverter 13, and the power P4 produced by the device generation of electrical energy G4 is transmitted entirely to the inverter 14.

In this fourth configuration, the branch lines 10 between the switching devices C2 and C3 and between the switching devices C3 and C4 are open, as is the output 11 to the inverter 12. From this fourth configuration, the central unit 5 can switch the switching devices 8: - in the second configuration if P3 + P4 <Si, - and in the fifth configuration if P1 + P2> S2 and P3 + P4> Si.

Fifth configuration (FIG. 6) In the fifth configuration, the central unit 5 switches the switching devices 8 so that all the energy produced by each of the electric power generation devices G1-G4 is transmitted to the corresponding inverter 11-14, the branch lines 10 being all open. From this fifth configuration, the central unit 5 can switch the switching devices 8: 35 - to the second configuration if P1 + P2 <S1 and P3 + P4 <Si, - to the third configuration if P1 + P2> S1 and P3 + P4 <S1, - and to the fourth configuration if P1 + P2 <S1 and P3 + P4> S1. The switching thresholds S1, S2 may not be predetermined but variable, and these thresholds may be equal or different. Other switching algorithms are also possible, to determine the switching criteria of the switching devices 8, and to determine which inverters are supplied from the inverters I1-I4.

Claims (9)

REVENDICATIONS1. Power supply method for supplying a plurality of inverters (12) from an electricity generation plant (2) comprising at least one electrical energy generating device (3), said method comprising at least the steps following: (a) a measurement step in which at least one electrical parameter representative of an electrical power produced by the power generation plant (2), (b) and a power supply step is measured during of which, according to said electrical parameter, selectively supplying either an inverter (3) or several inverters (3) of the plurality of inverters from said electrical installation, by simple switching of a power supply device (4) interposed between the electrical installation (2) and the inverters (12). 2. The method according to claim 1, wherein the power generation plant (2) comprises a plurality of electrical energy generating devices (3), and wherein: during the measuring step (a) several electrical parameters representative of the electric powers produced by the electric power generation devices (3) are measured, and, according to said electrical parameters, the electrical powers produced by the electrical energy generating devices are distributed. selectively on one or more of the inverters () during step (b). 3. The method according to claim 2, wherein, during step (b), the electric powers produced by several devices (3) for generating electrical energy are grouped together on one and the same inverter (12). the electric powers produced by these devices for generating electrical energy are below a certain first threshold, and the electrical powers produced by these electrical energy generation devices are sent to respective inverters (12), respectively, when the powers electrical generated by these electric power generation devices are greater than a second threshold. 4. A power supply device (4) for supplying a plurality of inverters (12) from a power generation plant (2) comprising at least one device (3) for generating electrical energy, which power supply device (4) comprising: at least one power input (9) for connection to said electric power generating device (3) for receiving electrical energy produced by said electric power generating device a plurality of power outputs (11) intended to be respectively connected to the inverters (12) of said plurality of inverters for powering said inverters, a control device (5, 8) adapted for, according to less an electrical parameter representative of an electric power produced by the power generation plant (2), selectively powering by switching, either a power output (11), or several power outputs; e (11) from said at least one power input (9). 5. Power supply device according to claim 4, comprising at least one data input (6) adapted to receive said at least one electrical parameter. 6. Power supply device according to claim 4 or claim 5, comprising a plurality of power inputs (11) for receiving respectively the electrical energy produced by several devices (3) for generating electrical energy, and the device for control (5, 8) is adapted to, as a function of electrical parameters representative of electric powers available at each power input (9), distribute the available electrical powers to the different power inputs selectively on one or more power outputs (11) . 7. Feeding device according to claim 6, wherein the control device is adapted to group on the same power output (11), the electric power available to several power inputs (9), as the said power available these power inputs are below a certain first threshold, and to send the available electrical powers to these power inputs respectively to several distinct power outputs, when said available electrical powers to said power inputs are greater than a second threshold. 8. Feeding device according to any one of claims 6 and 7, wherein the control device comprises an electronic central unit (5) controlling switching devices (8) which each connect at least one device (3) of generating electrical energy to an inverter (12) and which are interconnected by branch lines (10), which switching devices are each adapted to selectively open or close a power output (11) and open or close at minus one branch line (10). 9. Electrical installation comprising: a plurality of inverters (12), an electricity generating installation (2) comprising at least one device (3) for generating electrical energy, a power supply device (4) according to any one of claims 4 to 8, wherein said at least one power input (9) is connected to said electric power generating device (3) for receiving electrical energy produced by said electric power generating device , and whose power outputs (11) are respectively connected to the inverters (12) of said plurality of inverters for supplying said inverters.