Power supply system

Abstract

To provide a power supply system for precisely calculating actual output suppression power when output is suppressed.SOLUTION: A power supply system 10 includes: a plurality of solar panels 21 to 24; a power collection box 40 for bundling output power of the plurality of power conditioners 31 to 34; a load 90 which is connected to the plurality of power conditioners 31 to 34 through the power collection box 40 and is interconnected to a commercial power system; and a centralized control device 60 which controls operation of the plurality of power conditioners 31 to 34 in a centralized manner. Output power of the plurality of power conditioners 31 to 34 is supplied to the load and can be reverse-flowed to the commercial power system. The centralized control device 60 sequentially switches at least one of the plurality of power conditioners 31 to 34 to normal power generation control without output suppression in a rotational manner, and performs output suppression control on the remaining power conditioners so as to achieve an output suppression rate as the system.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a power supply system capable of reverse power flow to a commercial power system.

Background Art

[0002] Currently, a power supply system equipped with a distributed power source having a solar power generation facility and connected to a commercial power system is widespread. In such a power supply system, if the power supplied (reverse power flow) from the distributed power source to the commercial power system excessively increases, it may have an adverse effect on the quality of the commercial power system.

[0003] For this reason, there are cases where output suppression is imposed by the power company. When output suppression is imposed, from the perspective of the owner of the distributed power source, "the power that could originally be generated is suppressed", resulting in an economic disadvantage.

[0004] Conventionally, for example, as shown in Patent Document 1, when output suppression is imposed, the difference between the predicted power generation amount for that time (how many kWh could be generated during a predetermined period based on solar radiation amount prediction data, etc.) and the actual power generation amount is multiplied by the power rate unit price to calculate "how much economic loss has occurred".

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, in the conventional configuration, predicted power generation is used, and it is not known to what extent output suppression has been performed on the actual power generation capacity.

[0007] Therefore, the calculated economic loss value is also an estimated value, and it cannot be said that the economic loss value has been accurately calculated.

[0008] Therefore, an object of the present invention is to accurately calculate the actual output suppression power amount during output suppression.

Means for Solving the Problems

[0009] The power supply system of this invention includes a plurality of solar panels, a plurality of power conditioners each connected to the plurality of solar panels, a power collection box that bundles the output power of the plurality of power conditioners, a load that is connected to the plurality of power conditioners via the power collection box and is linked to the commercial power system, and a central control device that centrally controls the operations of the plurality of power conditioners. It is a full-scale power selling type power supply system that supplies the output power of the plurality of power conditioners to the load and can feed power back to the commercial power system.

[0010] When the central control device receives a command for output suppression, it acquires the output suppression rate of the system as a whole. Among the plurality of power conditioners, the central control device sets at least one power conditioner to normal power generation control without applying output suppression. Normal power generation control is control in which output suppression of the power conditioner is not applied, that is, the solar panel performs MPPT control and outputs the generated power as much as possible at that time. Since the generated power of the solar panel varies according to the solar irradiance, just because MPPT control is being performed, it is not necessarily a constant value. The central control device performs output suppression control so as to achieve the output suppression rate of the system as a whole with the remaining power conditioners. The central control device sequentially switches the power conditioner to be subjected to normal power generation control in a rotation order.

[0011] The power supply system of this invention includes a plurality of solar panels, a plurality of power conditioners each connected to a respective one of the solar panels, a power collection box that bundles the output power of the plurality of power conditioners, a load that is connected to the plurality of power conditioners via the power collection box and is linked to the commercial power grid, and a central control device that centrally controls the operation of the plurality of power conditioners. It is a self-consumption type power supply system that supplies the output power of the plurality of power conditioners to the load and prohibits reverse power flow to the commercial power grid.

[0012] When the central control device detects the possibility of reverse power flow, it calculates the output suppression rate of the system as a whole. The central control device sets at least one of the plurality of power conditioners to normal power generation control without applying output suppression. The central control device performs output suppression control so as to achieve the output suppression rate of the system as a whole with the remaining power conditioners. The central control device sequentially switches the power conditioner to be under normal power generation control in a rotation system.

[0013] In these power supply systems, when output suppression of the system as a whole must be performed, it is possible to know how much power the plurality of power conditioners can actually output. Thereby, the actual suppressed power amount of the power can be accurately calculated.

Advantages of the Invention

[0014] According to this invention, the actual output suppression power amount during output suppression can be accurately calculated.

Brief Description of the Drawings

[0015]

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BEST MODE FOR CARRYING OUT THE INVENTION

[0016] [First Embodiment] A power supply system according to the first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a functional block diagram of the power supply system according to the first embodiment.

[0017] As shown in FIG. 1, the power supply system 10 includes a plurality of solar panels 21-24, a plurality of power conditioners (PCS) 31-34, a power collection box 40, a power meter 50, a central control device 60, a load 90, a current sensor CT, and a switch SW. In this embodiment, the number of solar panels and power conditioners is four, but the number is not limited to this.

[0018] The solar panel 21 is connected to the power conditioner 31, and the solar panel 22 is connected to the power conditioner 32. The solar panel 23 is connected to the power conditioner 33, and the solar panel 24 is connected to the power conditioner 34.

[0019] The rated output of the pair of the solar panel 21 and the power conditioner 31, the rated output of the pair of the solar panel 22 and the power conditioner 32, the rated output of the pair of the solar panel 23 and the power conditioner 33, and the rated output of the pair of the solar panel 24 and the power conditioner 34 are the same.

[0020] The plurality of power conditioners 31-34 are connected to the power collection box 40. The power collection box 40 is connected to the load 90 via the switch SW. The node between the switch SW and the load 90 is connected to the power grid (commercial power grid). A current sensor CT is arranged on this connection line. The opening and closing control of the switch SW is performed by the current detected by the current sensor CT.

[0021] The power meter 50 is connected to the connection line. The central control device 60 is connected to the power meter 50.

[0022] In such a configuration, the power generated by the plurality of solar panels 21-24 is output from the plurality of power conditioners 31-34 and bundled in the power collection box 40. The bundled power is supplied to the load 90, and the surplus power is output to the power grid (reverse power flow).

[0023] Thereby, the power supply system 10 constitutes a full-capacity selling power supply system capable of reverse power flow to the power grid.

[0024] In such a configuration, the central control device 60 performs the following control.

[0025] FIG. 2 is a flowchart showing an example of power output control of the power supply system according to the first embodiment.

[0026] If the central control device 60 has not received a command to suppress output from a power company or the like (S11: NO), it performs normal power generation control on all the power conditioners 31-34. Normal power generation control does not suppress the output of the power conditioner, that is, the solar panel performs MPPT control and outputs the generated power that can be output at that time. For example, the central control device 60 controls all the solar panels 21-24 to perform MPPT (Maximum Power Point Tracking) control for all the power conditioners 31-34 and controls them to generate power.

[0027] When the central control device 60 receives a command to suppress output (S11: YES), it performs output suppression control by means of rotation operation as described below.

[0028] The command to suppress output includes the output suppression rate with respect to the maximum rated output. For example, the command to suppress output includes suppressing the output to 50% of the maximum rated output.

[0029] The central control device 60 acquires the output suppression rate from the command to suppress output (S12). The central control device 60 sets this output suppression rate as the output suppression rate of the power supply system 10.

[0030] The central control device 60 centrally controls a plurality of power conditioners 31-34. More specifically, the central control device 60 normally performs power generation control on one power conditioner (S13). Further, the central control device 60 performs output suppression control on the remaining power conditioners other than the power conditioner performing the normal power generation control (S14).

[0031] At this time, the central control device 60 controls the output suppression of the remaining power conditioners so as to achieve the output suppression rate of the power supply system 10.

[0032] The central control device 60 continues this state for a time of a predetermined rotation cycle (for example, 30 minutes, 1 hour, etc.).

[0033] When the time of the rotation cycle has elapsed, the central control device 60 switches the power conditioner performing the normal power generation control (S15).

[0034] Thereafter, the central control device 60 repeats the above control until the command for output suppression is released.

[0035] By performing such control, the central control device 60 can obtain the output power (maximum output power) in the normal power generation control of the plurality of power conditioners 31-34 even during output suppression. This maximum output power is based on the environment at the time when output suppression is being performed.

[0036] Therefore, the central control device 60 can obtain the maximum output power of the plurality of power conditioners 31-34 in real time during output suppression.

[0037] Also, since the central control device 60 grasps the suppression rate of each power conditioner performing output suppression, it can obtain the output power (suppressed output power) of each power conditioner performing output suppression.

[0038] Thus, while receiving the output suppression command, the central control device 60 acquires the maximum output power and the suppressed output power of the plurality of power conditioners 31-34.

[0039] For each of the plurality of power conditioners 31-34, the central control device 60 calculates the difference value between the maximum output power and the suppressed output power. Thereby, the central control device 60 can calculate the power that could not be output (loss power due to the suppression command) due to the output suppression.

[0040] (Specific Example 1-1: Output suppression rate 50%) FIG. 3 is a diagram showing an example of the generated power amount in the rotation control in the power supply system according to the first embodiment when output suppression is performed. As an example, it is the generated power amount output by each of the plurality of power conditioners 31-34 during 30 minutes. The command of the output suppression value is performed in units of 1% every 30 minutes. Since the generated power fluctuates depending on the solar radiation conditions and the like, in reality, the output power of the power conditioner also fluctuates even during 30 minutes. Here, for the sake of simplicity of explanation, it is explained as if a constant generated power continues for 30 minutes. Note that the generated power amount indicated by the dotted line in FIG. 3 indicates the predicted generated power amount using weather forecasts and the like as in the conventional case. Further, FIG. 3 shows the case where the output suppression rate is 50%, PR indicates the maximum rated power amount of the plurality of power conditioners 31-34, and PC indicates the generated power amount when the plurality of power conditioners 31-34 perform output suppression evenly when the output suppression rate of the power supply system 10 is 50%.

[0041] Further, FIG. 3 shows the case where the rated output of the plurality of power conditioners 31-34 is 9 kW. In this case, the maximum output of the power supply system 10 is 9 kW × 4 units = 36 kW.

[0042] When receiving the command with an output suppression rate of 50%, the central control device 60 needs to perform output limitation to 36 kW × 0.5 = 18 kW as the power supply system 10. In contrast, the following output suppression control by rotation is performed.

[0043] First period (T1) of rotation control The central control device 60 controls the power conditioner 31 to perform normal power generation control, and controls the output suppression of the plurality of power conditioners 32-34.

[0044] At this time, it is assumed that the power conditioner 31 was able to output (generate power) at 100% (9 kW), while the predicted value was 95% of the rated output. The central control device 60 acquires this and suppresses the output of the plurality of power conditioners 32-34 so as to achieve an output suppression of 50% of the rated output of the power supply system 10. In other words, the central control device 60 suppresses the output of the plurality of power conditioners 32-34 so that the power supply system 10 does not exceed 18 kW. In this case, since 18 kW - 9 kW = 9 kW is evenly set for the plurality of power conditioners 32-34, the generated power of 9 kW / 3 units = 3 kW is set for each of the power conditioners 32-34.

[0045] The central control device 60 performs output suppression control on the plurality of power conditioners 31-34 to generate power at 3 kW, that is, approximately 33.3% of the rated output.

[0046] And through this first period (T1) of rotation control, the central control device 60 can acquire the maximum output power of the power conditioner 31 in the current environment.

[0047] Second period (T2) of rotation control The central control device 60 controls the power conditioner 32 to perform normal power generation control, and controls the output suppression of the plurality of power conditioners 31, 33, and 34.

[0048] At this time, assume that the power conditioner 32 was able to output (generate power) at 95% (8.55 kW) while the predicted value was 90% of the rated output. The central control device 60 acquires this and suppresses the output of the plurality of power conditioners 31, 33, and 34 so as to achieve output suppression of 50% of the rated output of the power supply system 10. In other words, so that it does not exceed 18 kW as the power supply system 10. In this case, since 18 kW - 8.55 kW = 9.45 kW is evenly set for the plurality of power conditioners 31, 33, and 34, the generated power of 9.45 kW / 3 units = 3.15 kW is set for each of the power conditioners 31, 33, and 34.

[0049] The central control device 60 performs output suppression control on the plurality of power conditioners 31, 33, and 34 so as to generate power at 3.15 kW, that is, approximately 35% of the rated output.

[0050] And by this second period (T2) of the rotation control, the central control device 60 can acquire the maximum output power of the power conditioner 32 in the current environment.

[0051] The third period (T3) of the rotation control The central control device 60 controls the power conditioner 33 to perform normal power generation control and controls the output suppression of the plurality of power conditioners 31, 32, and 34.

[0052] At this time, assume that the power conditioner 33 was able to output (generate power) at 80% (7.2 kW) while the predicted value was 80% of the rated output. The central control device 60 acquires this and suppresses the output of the plurality of power conditioners 31, 32, and 34 so as to achieve output suppression of 50% of the rated output of the power supply system 10. In other words, so that it does not exceed 18 kW as the power supply system 10. In this case, since 18 kW - 7.2 kW = 10.8 kW is evenly set for the plurality of power conditioners 31, 32, and 34, the generated power of 10.8 kW / 3 units = 3.6 kW is set for each of the power conditioners 31, 32, and 34.

[0053] The central control device 60 performs output suppression control on the plurality of power conditioners 31, 32, and 34 so as to generate power at 3.6 kW, that is, about 40% of the rated output.

[0054] Then, by this third period (T3) of the rotation control, the central control device 60 can acquire the maximum output power of the power conditioner 33 in the current environment.

[0055] The fourth period (T4) of the rotation control The central control device 60 controls the power conditioner 34 to perform normal power generation control, and performs output suppression control on the plurality of power conditioners 31 - 33.

[0056] At this time, assume that the power conditioner 34 was able to output (generate power) at 80% (7.2 kW) while the predicted value was 85% of the rated output. The central control device 60 acquires this and performs output suppression on the plurality of power conditioners 31 - 33 so as to achieve output suppression of 50% of the rated output as the power supply system 10, that is, so as not to exceed 18 kW as the power supply system 10. In this case, since 18 kW - 7.2 kW = 10.8 kW is evenly set for the plurality of power conditioners 31 - 33, the power generation power of 10.8 kW / 3 units = 3.6 kW is set for each of the power conditioners 31 - 33.

[0057] The central control device 60 performs output suppression control on the plurality of power conditioners 31 - 33 so as to generate power at 3.6 kW, that is, about 40% of the rated output.

[0058] Then, by this fourth period (T4) of the rotation control, the central control device 60 can acquire the maximum output power of the power conditioner 34 in the current environment.

[0059] Hereinafter, the central control device 60 and the plurality of power conditioners 31-34 repeat the rotation control in the order of the above-described first period (T1), second period (T2), third period (T3), and fourth period (T4). Thereby, the power supply system 10 can continue power generation while observing the output suppression.

[0060] Furthermore, in each period of the rotation control, the maximum output power of the plurality of power conditioners 31-34 in the current environment can be obtained. Thereby, the central control device 60 can calculate the difference value between the maximum output power and the suppressed output power, and can accurately calculate the power (loss power due to the suppression command) that could not be output (generated) due to the output suppression.

[0061] Note that the central control device 60 can also calculate the economic loss value based on the power difference (loss power due to the suppression command) of the plurality of power conditioners. Since the loss power due to the suppression command is accurately calculated, the central control device 60 can accurately calculate the economic loss value.

[0062] (Specific Examples 1-2: Output suppression rate 30%) FIG. 4 is a diagram showing an example of the generated power amount in the rotation control in the power supply system according to the first embodiment when output suppression is performed. FIG. 4 is different from FIG. 3 in that the output suppression rate is 30%, and the other parts are shown with the same concept as FIG. 3. Therefore, the description of FIG. 4 will be omitted within the range understandable by referring to the description of FIG. 3.

[0063] First period (T1) of the rotation control The central control device 60 controls the power conditioner 31 to perform normal power generation control, and controls the output suppression of the plurality of power conditioners 32-34.

[0064] Assume that the power conditioner 31 can output (generate power) at 100%. The central control device 60 performs output suppression control on the plurality of power conditioners 32-34 so as to generate power at about 6.7% of the rated output. Thereby, the power supply system 10 can achieve 30% output suppression.

[0065] And during the first period (T1) of this rotation control, the central control device 60 can obtain the maximum output power of the power conditioner 31 in the current environment.

[0066] The second period (T2) of rotation control The central control device 60 controls the power conditioner 32 to perform normal power generation control, and controls the output suppression of the plurality of power conditioners 31, 33, and 34.

[0067] Assume that the power conditioner 32 can output (generate power) at 90%. The central control device 60 performs output suppression control on the plurality of power conditioners 31, 33, and 34 so as to generate power at about 10% of the rated output. Thereby, the power supply system 10 can achieve 30% output suppression.

[0068] And during the second period (T2) of this rotation control, the central control device 60 can obtain the maximum output power of the power conditioner 32 in the current environment.

[0069] The third period (T3) of rotation control The central control device 60 controls the power conditioner 33 to perform normal power generation control, and controls the output suppression of the plurality of power conditioners 31, 32, and 34.

[0070] Assume that the power conditioner 33 can output (generate power) at 80%. The central control device 60 performs output suppression control on the plurality of power conditioners 31, 32, and 34 so as to generate power at about 16.7% of the rated output. Thereby, the power supply system 10 can achieve 30% output suppression.

[0071] And during the third period (T3) of this rotation control, the central control device 60 can obtain the maximum output power of the power conditioner 33 in the current environment.

[0072] The fourth period (T4) of rotation control The central control device 60 controls the power conditioner 34 to perform normal power generation control and controls the output suppression of the plurality of power conditioners 31-33.

[0073] Assume that the power conditioner 34 can output (generate power) at 90%. The central control device 60 performs output suppression control on the plurality of power conditioners 31-33 to generate power at about 10% of the rated output. Thereby, the power supply system 10 can achieve 30% output suppression.

[0074] Then, during the fourth period (T4) of this rotation control, the central control device 60 can obtain the maximum output power of the power conditioner 34 in the current environment.

[0075] In this way, the power supply system 10 can obtain the maximum output of the plurality of power conditioners 31-34 at that time while realizing the commanded output suppression according to the output suppression rate, and can accurately calculate the loss power due to the suppression command.

[0076] [Second Embodiment] The power supply system according to the second embodiment of the present invention will be described with reference to the drawings. The power supply system according to the second embodiment has the same configuration as the power supply system 10 according to the first embodiment, but is different in the specific content of the rotation control. Therefore, only the different parts will be specifically described below.

[0077] FIG. 5 is a flowchart showing an example of power output control of the power supply system according to the second embodiment.

[0078] If the central control device 60 has not received a command for output suppression from a power company or the like (S11: NO), it performs normal power generation control on all the power conditioners 31-34. For example, the central control device 60 controls all the solar panels 21-24 of all the power conditioners 31-34 to perform MPPT control and controls them to generate power.

[0079] When the central control device 60 receives a command for output suppression (S11: YES), it acquires the output suppression rate from the command for output suppression (S12). The central control device 60 sets this output suppression rate as the output suppression rate for the power supply system 10.

[0080] The central control device 60 performs normal power generation control on one power conditioner (S13). Further, the central control device 60 controls the output stop of at least one power conditioner (S21).

[0081] Then, the central control device 60 performs output suppression control on the remaining power conditioners other than the power conditioner that performs normal power generation control and the power conditioner whose output is stopped (S14).

[0082] At this time, the central control device 60 controls the output suppression of the remaining power conditioners so as to achieve the output suppression rate for the power supply system 10.

[0083] The central control device 60 continues this state over a time period of a predetermined rotation cycle (for example, 30 minutes, 1 hour, etc.).

[0084] When the time of the rotation cycle has elapsed, the central control device 60 switches the power conditioner that performs normal power generation control and the power conditioner that performs output stop control (S22).

[0085] Thereafter, the central control device 60 repeats the above control until the command for output suppression is canceled.

[0086] By performing such control, the central control device 60 acquires the maximum output power of the plurality of power conditioners 31 - 34 even during output suppression. Then, the central control device 60 calculates the difference value between the maximum output power and the output power during output suppression control for each of the plurality of power conditioners 31 - 34. Thereby, the central control device 60 can calculate the power that could not be output (generated) due to output suppression (loss power due to the suppression command).

[0087] (Specific Example 2-1: Output Suppression Rate 50%) FIG. 6 is a diagram showing an example of the generated power amount when output suppression is performed in the rotation control in the power supply system according to the second embodiment. FIG. 6 shows the case where the output suppression rate is 50%.

[0088] First period (T1) of rotation control The central control device 60 controls the power conditioner 31 to perform normal power generation control, and controls the power conditioner 34 to stop output. The central control device 60 performs output control on the remaining plurality of power conditioners 32 and 33.

[0089] Assume that the power conditioner 31 can output (generate power) at 100%. Since the output of the power conditioner 34 is 0% by the central control device 60, it controls so as to supplement the remaining output power with the plurality of power conditioners 32 and 33.

[0090] More specifically, the central control device 60 controls the power conditioner 32 to perform normal power generation control, and supplements the shortage by output suppression control of the power conditioner 33. Assume that the power conditioner 32 can output (generate power) at 90%. The central control device 60 performs output suppression control on the power conditioner 33 so as to generate power at about 10% of the rated output of the shortage. Thereby, the power supply system can achieve 50% output suppression.

[0091] And by this first period (T1) of rotation control, the central control device 60 can acquire the maximum output power of the power conditioners 31 and 32 in the current environment.

[0092] Second period (T2) of rotation control The central control device 60 controls the power conditioner 32 to perform normal power generation control, and controls the power conditioner 31 to stop output. The central control device 60 performs output control on the remaining plurality of power conditioners 33 and 34.

[0093] Assume that the power conditioner 32 can output (generate electricity) at 90%. Since the output of the power conditioner 31 is 0% in the central control device 60, it controls so as to supplement the remaining output power with a plurality of power conditioners 33 and 34.

[0094] More specifically, the central control device 60 controls the power conditioner 33 to perform normal power generation control, and supplements the shortage by output suppression control of the power conditioner 34. Assume that the power conditioner 33 can output (generate electricity) at 80%. The central control device 60 performs output suppression control on the power conditioner 34 to generate electricity at about 30% of the rated output of the shortage. Thereby, the power supply system can achieve 50% output suppression.

[0095] And by the second period (T2) of this rotation control, the central control device 60 can acquire the maximum output power of the power conditioners 32 and 33 in the current environment.

[0096] The third period (T3) of rotation control The central control device 60 controls the power conditioner 33 to perform normal power generation control, and controls the power conditioner 32 to stop output. The central control device 60 performs output control on the remaining plurality of power conditioners 34 and 31.

[0097] Assume that the power conditioner 33 can output (generate electricity) at 80%. Since the output of the power conditioner 32 is 0% in the central control device 60, it controls so as to supplement the remaining output power with a plurality of power conditioners 34 and 31.

[0098] More specifically, the central control device 60 controls the power conditioner 34 to perform normal power generation control, and compensates for the shortage by output suppression control of the power conditioner 31. Assume that the power conditioner 34 can output (generate power) at 90%. The central control device 60 performs output suppression control on the power conditioner 31 to generate power at about 30% of the rated output of the shortage. Thereby, the power supply system can achieve 50% output suppression.

[0099] And through the third period (T3) of this rotation control, the central control device 60 can obtain the maximum output power of the power conditioners 33 and 34 in the current environment.

[0100] The fourth period (T4) of the rotation control The central control device 60 controls the power conditioner 34 to perform normal power generation control, and controls the power conditioner 33 to stop output. The central control device 60 performs output control on the remaining plurality of power conditioners 31 and 32.

[0101] Assume that the power conditioner 34 can output (generate power) at 90%. Since the output of the power conditioner 33 is 0% for the central control device 60, it controls the remaining output power to be compensated by the plurality of power conditioners 31 and 32.

[0102] More specifically, the central control device 60 controls the power conditioner 31 to perform normal power generation control, and compensates for the shortage by output suppression control of the power conditioner 32. Assume that the power conditioner 31 can output (generate power) at 100%. The central control device 60 performs output suppression control on the power conditioner 32 to generate power at about 10% of the rated output of the shortage. Thereby, the power supply system can achieve 50% output suppression.

[0103] And through the fourth period (T4) of this rotation control, the central control device 60 can obtain the maximum output power of the power conditioners 34 and 31 in the current environment.

[0104] In this way, the power supply system can obtain the maximum output power of the plurality of power conditioners 31-34 at that time while realizing the commanded output suppression according to the output suppression rate, and can accurately calculate the power loss due to the suppression command.

[0105] (Specific Example 2-2: Output suppression rate 30%) FIG. 7 is a diagram showing an example of the generated power amount in the rotation control in the power supply system according to the second embodiment when output suppression is performed. FIG. 7 shows the case where the output suppression rate is 30%.

[0106] First period (T1) of rotation control The central control device 60 controls the power conditioner 31 to perform normal power generation control, and controls the power conditioner 34 to stop output. The central control device 60 performs output control on the remaining plurality of power conditioners 32, 33.

[0107] Assume that the power conditioner 31 can output (generate power) at 100%. Since the output of the power conditioner 34 is 0% by the central control device 60, it controls the remaining output power to be supplemented by the plurality of power conditioners 32, 33.

[0108] More specifically, the central control device 60 performs output suppression control on the power conditioner 32 so as not to exceed the output suppression rate. As a result, the power conditioner 32 is output-controlled at 20% of the rated output. At this time, since the output of the power conditioner 33 is not required, the central control device 60 performs output stop control on the power conditioner 33. Thereby, the power supply system can achieve 30% output suppression.

[0109] And by this first period (T1) of rotation control, the central control device 60 can obtain the maximum output power of the power conditioner 31 in the current environment.

[0110] Second period (T2) of rotation control The central control device 60 controls the power conditioner 32 to perform normal power generation control, and controls the power conditioner 31 to stop its output. The central control device 60 controls the output of the remaining plurality of power conditioners 33 and 34.

[0111] Assume that the power conditioner 32 can output (generate power) at 90%. Since the output of the power conditioner 31 is 0% for the central control device 60, it controls the remaining output power to be supplemented by the plurality of power conditioners 33 and 34.

[0112] More specifically, the central control device 60 performs output suppression control on the power conditioner 33 so as not to exceed the output suppression rate. As a result, the power conditioner 33 is output-controlled at 30% of its rated output. At this time, since the output of the power conditioner 34 is not required, the central control device 60 performs output stop control on the power conditioner 34. Thus, the power supply system can achieve a 30% output suppression.

[0113] And by this second period (T2) of the rotation control, the central control device 60 can obtain the maximum output power of the power conditioner 32 in the current environment.

[0114] The third period (T3) of the rotation control The central control device 60 controls the power conditioner 33 to perform normal power generation control, and controls the power conditioner 32 to stop its output. The central control device 60 controls the output of the remaining plurality of power conditioners 34 and 31.

[0115] Assume that the power conditioner 33 can output (generate power) at 80%. Since the output of the power conditioner 31 is 0% for the central control device 60, it controls the remaining output power to be supplemented by the plurality of power conditioners 33 and 34.

[0116] More specifically, the central control device 60 performs output suppression control on the power conditioner 34 so as not to exceed the output suppression rate. As a result, the power conditioner 34 is output-controlled at 30% of the rated output. At this time, since 10% of the shortage remains, the central control device 60 performs output suppression control of 10% of the rated output on the power conditioner 31. Thereby, the power supply system can achieve 30% output suppression. Note that at this time, the output suppression of the power conditioner 34 may be set to 40% of the rated power, and the power conditioner 31 may be stopped and controlled.

[0117] And by this third period (T3) of the rotation control, the central control device 60 can obtain the maximum output power of the power conditioner 33 in the current environment.

[0118] Fourth period (T4) of the rotation control The central control device 60 controls the power conditioner 34 to perform normal power generation control, and controls the power conditioner 33 to stop output. The central control device 60 performs output control on the remaining plurality of power conditioners 31 and 32.

[0119] Assume that the power conditioner 34 can output (generate power) at 90%. Since the output of the power conditioner 33 is 0% for the central control device 60, it controls so that the remaining output power is compensated by the plurality of power conditioners 31 and 32.

[0120] More specifically, the central control device 60 performs output suppression control on the power conditioner 31 so as not to exceed the output suppression rate. As a result, the power conditioner 33 is output-controlled at 30% of the rated output. At this time, since the output of the power conditioner 34 is not required, the central control device 60 performs output stop control on the power conditioner 34. Thereby, the power supply system can achieve 30% output suppression.

[0121] And by this fourth period (T4) of the rotation control, the central control device 60 can obtain the maximum output power of the power conditioner 34 in the current environment.

[0122] (Specific Example 2-3: Distribution such as 30% output suppression rate) FIG. 8 is a diagram showing an example of the generated power amount when output suppression is performed in the rotation control in the power supply system according to the second embodiment. FIG. 8 shows the case where the output suppression rate is 30%.

[0123] First period (T1) of rotation control The central control device 60 controls the power conditioner 31 to perform normal power generation control, and controls the power conditioner 34 to stop output. The central control device 60 performs output control of the remaining plurality of power conditioners 32 and 33.

[0124] Assume that the power conditioner 31 can output (generate power) at 100%. Since the output of the power conditioner 34 is 0% by the central control device 60, it controls so as to supplement the remaining output power with the plurality of power conditioners 32 and 33.

[0125] More specifically, the central control device 60 performs output suppression control in equal distribution on the power conditioners 32 and 33 so as not to exceed the output suppression rate. As a result, the power conditioners 32 and 33 are each output-controlled at 10% of the rated output. Thereby, the power supply system can achieve 30% output suppression.

[0126] And by this first period (T1) of rotation control, the central control device 60 can acquire the maximum output power of the power conditioner 31 in the current environment.

[0127] Second period (T2) of rotation control The central control device 60 controls the power conditioner 32 to perform normal power generation control, and controls the power conditioner 31 to stop output. The central control device 60 performs output control of the remaining plurality of power conditioners 33 and 34.

[0128] Assume that the power conditioner 32 can output (generate electricity) at 90%. Since the output of the power conditioner 31 is 0%, the central control device 60 controls the remaining output power to be supplemented by the plurality of power conditioners 33 and 34.

[0129] More specifically, the central control device 60 performs output suppression control in equal distribution on the power conditioners 33 and 34 so as not to exceed the output suppression rate. As a result, the power conditioners 33 and 34 are each controlled to output at 15% of the rated output. Thereby, the power supply system can achieve a 30% output suppression.

[0130] And by this second period (T2) of the rotation control, the central control device 60 can obtain the maximum output power of the power conditioner 32 in the current environment.

[0131] The third period (T3) of the rotation control The central control device 60 controls the power conditioner 33 to perform normal power generation control and controls the power conditioner 32 to stop output. The central control device 60 controls the output of the remaining plurality of power conditioners 34 and 31.

[0132] Assume that the power conditioner 33 can output (generate electricity) at 80%. Since the output of the power conditioner 32 is 0%, the central control device 60 controls the remaining output power to be supplemented by the plurality of power conditioners 34 and 31.

[0133] More specifically, the central control device 60 performs output suppression control in equal distribution on the power conditioners 34 and 31 so as not to exceed the output suppression rate. As a result, the power conditioners 34 and 31 are each controlled to output at 20% of the rated output. Thereby, the power supply system can achieve a 30% output suppression.

[0134] And by this third period (T3) of the rotation control, the central control device 60 can obtain the maximum output power of the power conditioner 33 in the current environment.

[0135] Fourth period (T4) of rotation control The central control device 60 controls the power conditioner 34 to perform normal power generation control, and controls the power conditioner 33 to stop output. The central control device 60 performs output control on the remaining plurality of power conditioners 31 and 32.

[0136] Assume that the power conditioner 34 can output (generate power) at 90%. Since the output of the power conditioner 33 is 0% by the central control device 60, it controls so as to supplement the remaining output power with the plurality of power conditioners 31 and 32.

[0137] More specifically, the central control device 60 performs output suppression control in equal distribution on the power conditioners 31 and 32 so as not to exceed the output suppression rate. As a result, the power conditioners 31 and 32 are each output-controlled at 15% of the rated output. As a result, the power supply system can achieve a 30% output suppression.

[0138] And by this fourth period (T4) of rotation control, the central control device 60 can obtain the maximum output power of the power conditioner 34 in the current environment.

[0139] [Third Embodiment] The power supply system according to the third embodiment of the present invention will be described with reference to the drawings. The power supply system according to the third embodiment has the same configuration as the power supply system 10 according to the first embodiment, but is different in the specific content of the rotation control. Therefore, only the different parts will be specifically described below.

[0140] FIG. 9 is a flowchart showing an example of power output control of the power supply system according to the third embodiment.

[0141] If the central control device 60 has not received a command for output suppression (S11: NO), it performs normal power generation control for all the power conditioners 31-34. For example, the central control device 60 controls all the solar panels 21-24 for all the power conditioners 31-34 to perform MPPT control and control the power generation.

[0142] When the central control device 60 receives a command for output suppression (S11: YES), it obtains the output suppression rate from the command for output suppression (S12). The central control device 60 sets this output suppression rate as the output suppression rate of the power supply system 10.

[0143] The central control device 60 performs normal power generation control for one power conditioner (S13). Further, the central control device 60 sets the power conditioner for normal power generation control as much as possible (S31).

[0144] Then, the central control device 60 performs output suppression control for the remaining power conditioners other than the power conditioner for normal power generation control and the power conditioner for output stop (S14).

[0145] At this time, the central control device 60 controls the output suppression of the remaining power conditioners so as to achieve the output suppression rate of the power supply system 10.

[0146] The central control device 60 continues this state for a time of a predetermined rotation cycle (for example, 30 minutes or 1 hour, etc.).

[0147] When the time of the rotation cycle has elapsed, the central control device 60 switches the power conditioner for normal power generation control (S15).

[0148] Thereafter, the central control device 60 repeats the above control until the command for output suppression is released.

[0149] By performing such control, the central control device 60 obtains the maximum output power of the plurality of power conditioners 31-34 even during output suppression. Then, the central control device 60 calculates the difference value between the maximum output power and the suppressed output power for each of the plurality of power conditioners 31-34. Thereby, the central control device 60 can calculate the power that could not be output (generated) due to output suppression (loss power due to suppression command).

[0150] (Specific Example 3: Output suppression rate 50%) FIG. 10 is a diagram showing an example of the generated power amount in the rotation control in the power supply system according to the third embodiment when output suppression is performed. FIG. 10 shows the case where the output suppression rate is 50%.

[0151] First period (T1) of rotation control The central control device 60 controls the power conditioner 31 to perform normal power generation control. The central control device 60 performs output control on the remaining plurality of power conditioners 32-34. More specifically, the central control device 60 performs output control so that as many power conditioners as possible that perform normal power generation control are included in the remaining plurality of power conditioners 32-34.

[0152] Assume that the power conditioner 31 can output (generate power) at 100%. The central control device 60 controls so that the remaining output power is supplemented by the plurality of power conditioners 32-34.

[0153] More specifically, the central control device 60 controls the power conditioner 32 to perform normal power generation control, and distributes the shortage to the power conditioners 33 and 34 and supplements it by output suppression control. Assume that the power conditioner 32 can output (generate power) at 90%. The central control device 60 performs output suppression control so that the power conditioners 33 and 34 each generate power at about 5% of the rated output of the shortage. Thereby, the power supply system can achieve 50% output suppression.

[0154] And during the first period (T1) of this rotation control, the central control device 60 can obtain the maximum output power of the power conditioners 31 and 32 in the current environment.

[0155] The second period (T2) of rotation control The central control device 60 controls the power conditioner 32 to perform normal power generation control. The central control device 60 performs output control on the remaining plurality of power conditioners 31, 33, and 34. More specifically, the central control device 60 performs output control on the remaining plurality of power conditioners 31, 33, and 34 so that as many power conditioners as possible perform normal power generation control.

[0156] Assume that the power conditioner 32 can output (generate power) at 90%. The central control device 60 controls so as to supplement the remaining output power with the plurality of power conditioners 31, 33, and 34.

[0157] More specifically, the central control device 60 controls the power conditioner 33 to perform normal power generation control, and distributes the shortage among the power conditioners 33 and 34 and supplements it by output suppression control. Assume that the power conditioner 33 can output (generate power) at 80%. The central control device 60 performs output suppression control so that the power conditioners 34 and 31 each generate power at about 15% of the rated output of the shortage. Thereby, the power supply system can achieve 50% output suppression.

[0158] And during the second period (T2) of this rotation control, the central control device 60 can obtain the maximum output power of the power conditioners 32 and 33 in the current environment.

[0159] The third period (T3) of rotation control The central control device 60 controls the power conditioner 33 to perform normal power generation control. The central control device 60 performs output control on the remaining plurality of power conditioners 31, 32, and 34. More specifically, the central control device 60 performs output control on the remaining plurality of power conditioners 31, 32, and 34 so that as many power conditioners as possible perform normal power generation control.

[0160] Suppose the power conditioner 33 can output (generate power) at 80%. The central control device 60 controls the remaining power conditioners 31, 32, and 34 to supplement the remaining output power.

[0161] More specifically, the central control device 60 controls the power conditioner 34 to perform normal power generation control, and distributes the shortage to the power conditioners 31 and 32 and supplements it by output suppression control. Suppose the power conditioner 34 can output (generate power) at 90%. The central control device 60 performs output suppression control on the power conditioners 31 and 32 to generate power at about 15% of the rated output of the shortage respectively. Thereby, the power supply system can achieve 50% output suppression.

[0162] And in the third period (T3) of this rotation control, the central control device 60 can obtain the maximum output power of the power conditioners 33 and 34 in the current environment.

[0163] The fourth period (T4) of rotation control The central control device 60 controls the power conditioner 34 to perform normal power generation control. The central control device 60 performs output control on the remaining plurality of power conditioners 31 - 33. More specifically, the central control device 60 performs output control on the remaining plurality of power conditioners 31 - 33 so that as many power conditioners as possible perform normal power generation control.

[0164] Assume that the power conditioner 34 can output (generate power) at 90%. The central control device 60 controls so as to supplement the remaining output power with a plurality of power conditioners 31-33.

[0165] More specifically, the central control device 60 controls the power conditioner 31 to perform normal power generation control, and distributes the shortage to the power conditioners 32 and 33 and supplements it by output suppression control. Assume that the power conditioner 31 can output (generate power) at 100%. The central control device 60 performs output suppression control on the power conditioners 32 and 33 so that they each generate power at about 5% of the rated output of the shortage. Thereby, the power supply system can achieve 50% output suppression.

[0166] And by this fourth period (T4) of the rotation control, the central control device 60 can acquire the maximum output power of the power conditioners 34 and 31 in the current environment.

[0167] [Fourth Embodiment] The power supply system according to the fourth embodiment of the present invention will be described with reference to the drawings. The power supply system according to the fourth embodiment has the same configuration as the power supply system 10 according to the first embodiment, and is different in that it further performs failure detection. Therefore, only the different parts will be specifically described below.

[0168] FIG. 11 is a flowchart showing an example of power output control of the power supply system according to the fourth embodiment. Note that steps S11-S15 and S90 in FIG. 11 perform the same processing as the flowchart shown in the first embodiment (see FIG. 2), and the description thereof is omitted.

[0169] The central control device 60 detects whether or not the rotation control has completed one cycle. If the rotation control has not completed one cycle (S41: NO), the central control device 60 continues the output suppression control by the above-described rotation control.

[0170] If the rotation control has been completed once (S41: YES), the central control device 60 detects whether there is a power conditioner with a constant output power of zero (0%). If the central control device 60 determines that there is no power conditioner with a constant output power of zero (0%) (S42: NO), it repeats the rotation control as it is.

[0171] If the central control device 60 determines that there is a power conditioner with a constant output power of zero (0%) (S42: YES), it determines that the power conditioner with a constant output power of zero (0%) has failed (S43).

[0172] By performing such control and processing, the central control device 60 can determine the failed power conditioner while performing output suppression.

[0173] (Specific Example 4: Output suppression rate 50%) FIG. 12 is a diagram showing an example of the generated power amount when output suppression is performed in the rotation control in the power supply system according to the fourth embodiment. FIG. 12 shows the case where the output suppression rate is 50%.

[0174] First period (T1) of rotation control The central control device 60 controls the power conditioner 31 to perform normal power generation control. The central control device 60 performs output control on the remaining plurality of power conditioners 32 - 34. More specifically, the central control device 60 performs output control so as to evenly distribute the output power to the remaining plurality of power conditioners 32 - 34.

[0175] Assume that the power conditioner 31 can output (generate power) at 100%. The central control device 60 controls the remaining output power to be equally supplemented by the plurality of power conditioners 32 - 34.

[0176] Here, if the power conditioner 33 fails, the output power becomes 0%. In this case, the power conditioners 32 and 34 generate power with output suppression at 50% of the rated output. As a result, as a power supply system, a state with an output suppression rate of 50% is realized.

[0177] Second period (T2) of rotation control The central control device 60 controls the power conditioner 32 to perform normal power generation control. The central control device 60 performs output control on the outputs of the remaining plurality of power conditioners 31, 33, and 34. More specifically, the central control device 60 performs output control so as to evenly distribute the output power to the remaining plurality of power conditioners 31, 33, and 34.

[0178] Assume that the power conditioner 32 can output (generate power) at 90%. The central control device 60 controls so as to equally supplement the remaining output power with the plurality of power conditioners 31, 33, and 34.

[0179] Here, if the power conditioner 33 fails, the output power becomes 0%. In this case, the power conditioners 34 and 31 generate power with output suppression at 55% of the rated output. As a result, as a power supply system, a state with an output suppression rate of 50% is realized.

[0180] Third period (T3) of rotation control The central control device 60 controls the power conditioner 33 to perform normal power generation control. The central control device 60 performs output control on the outputs of the remaining plurality of power conditioners 31, 32, and 34. More specifically, the central control device 60 performs output control so as to evenly distribute the output power to the remaining plurality of power conditioners 31, 32, and 34.

[0181] Here, if the power conditioner 33 fails, the output power becomes 0%. In this case, the power conditioners 34, 31, and 32 generate power with output suppression at approximately 66.7% of the rated output. As a result, as a power supply system, a state with an output suppression rate of 50% is realized.

[0182] Fourth period (T4) of rotation control The central control device 60 controls the power conditioner 34 to perform normal power generation control. The central control device 60 performs output control of the remaining plurality of power conditioners 31 - 33. More specifically, the central control device 60 performs output control so as to evenly distribute the output power to the remaining plurality of power conditioners 31 - 33.

[0183] Assume that the power conditioner 34 can output (generate power) at 90%. The central control device 60 controls so as to equally supplement the remaining output power with the plurality of power conditioners 31 - 33.

[0184] Here, if the power conditioner 33 fails, the output power becomes 0%. In this case, the power conditioners 31 and 32 generate power with output suppression at 55% of the rated output. As a result, as a power supply system, a state with an output suppression rate of 50% is realized.

[0185] Thus, when there is a failed power conditioner, the output power of all the power conditioners is different from the case where there is no failed power conditioner.

[0186] The central control device 60 can determine the failed power conditioner by detecting this change.

[0187] [Fifth Embodiment] The power supply system according to the fifth embodiment of the present invention will be described with reference to the drawings. The power supply system according to the fifth embodiment is different from the power supply system 10 according to the first embodiment in that the rated outputs of the plurality of power conditioners do not match. Specifically, in the power supply system according to the fifth embodiment, the rated outputs of the power conditioners 33 and 34 are half (1 / 2) of the rated outputs of the power conditioners 31 and 32.

[0188] Even with such a configuration, the same control as in the first embodiment is possible.

[0189] (Specific Example 5: Output Suppression Rate 50%) FIG. 13 is a diagram showing an example of the generated power amount when output suppression is performed in the rotation control in the power supply system according to the fifth embodiment. FIG. 13 shows the case where the output suppression rate is 50%. In FIG. 13, PR1 is the rated output power of the power conditioners 31 and 32, and PR2 is the rated output power of the power conditioners 33 and 34.

[0190] First period (T1) of rotation control The central control device 60 controls the power conditioner 31 to perform normal power generation control. The central control device 60 performs output suppression control on the remaining plurality of power conditioners 32-34 so as to distribute the output power according to the rated output.

[0191] Assume that the power conditioner 31 can output (generate power) at 100%. The central control device 60 controls the remaining output power to be supplemented by the plurality of power conditioners 32-34.

[0192] Specifically, the central control device 60 performs output suppression on the power conditioner 32 so that it becomes 25% of the rated output PR1. The central control device 60 performs output suppression on the power conditioners 33 and 34 so that they become 25% of the rated output PR2, respectively.

[0193] As a result, the power supply system realizes a state where the output suppression rate is 50%.

[0194] And, by this first period (T1) of rotation control, the central control device 60 can obtain the maximum output power of the power conditioner 31 in the current environment.

[0195] Second period (T2) of rotation control The central control device 60 controls the power conditioner 32 to perform normal power generation control. The central control device 60 performs output suppression control on the remaining plurality of power conditioners 31, 33, and 34 so as to distribute the output power according to the rated output.

[0196] Assume that the power conditioner 31 can output (generate power) at 95%. The central control device 60 controls so as to supplement the remaining output power with a plurality of power conditioners 31, 33, and 34.

[0197] Specifically, the central control device 60 performs output suppression on the power conditioners 33 and 34 so that each becomes approximately 27.5% of the rated output PR2. The central control device 60 performs output suppression on the power conditioner 31 so that it becomes approximately 27.5% of the rated output PR1.

[0198] As a result, as the power supply system, a state with an output suppression rate of 50% is realized.

[0199] And by this second period (T2) of the rotation control, the central control device 60 can obtain the maximum output power of the power conditioner 32 in the current environment.

[0200] Third period (T3) of the rotation control The central control device 60 controls the power conditioner 33 to perform normal power generation control. The central control device 60 performs output suppression control so as to distribute the output power according to the rated output to the remaining plurality of power conditioners 31, 32, and 34.

[0201] Assume that the power conditioner 33 can output (generate power) at 80%. The central control device 60 controls so as to supplement the remaining output power with a plurality of power conditioners 31, 32, and 34.

[0202] Specifically, the central control device 60 performs output suppression on the power conditioner 34 so that it becomes approximately 44% of the rated output PR2. The central control device 60 performs output suppression on the power conditioner 31 so that it becomes approximately 44% of the rated output PR1.

[0203] As a result, as the power supply system, a state with an output suppression rate of 50% is realized.

[0204] Then, during the third period (T3) of this rotation control, the central control device 60 can obtain the maximum output power of the power conditioner 33 in the current environment.

[0205] Fourth period (T4) of rotation control The central control device 60 controls the power conditioner 34 to perform normal power generation control. The central control device 60 performs output suppression control on the remaining plurality of power conditioners 31-33 so as to distribute the output power according to the rated output.

[0206] Assume that the power conditioner 34 can output (generate power) at 80%. The central control device 60 controls the remaining output power to be supplemented by the plurality of power conditioners 31-33.

[0207] Specifically, the central control device 60 performs output suppression on the power conditioners 31 and 32 so that they are each about 44% of the rated output PR1. The central control device 60 performs output suppression on the power conditioner 33 so that it is about 44% of the rated output PR2.

[0208] Thereby, as a power supply system, a state with an output suppression rate of 50% is realized.

[0209] Then, during the fourth period (T4) of this rotation control, the central control device 60 can obtain the maximum output power of the power conditioner 34 in the current environment.

[0210] [Sixth Embodiment] The power supply system according to the sixth embodiment of the present invention will be described with reference to the drawings. FIG. 14 is a functional block diagram of the power supply system according to the sixth embodiment.

[0211] The power supply system 10X according to the sixth embodiment is different in that it is a self-consumption type power supply system, while the power supply system 10 according to the first embodiment is a full-sale type power supply system. Other configurations of the power supply system 10X are the same as those of the power supply system 10, and descriptions of the same parts will be omitted.

[0212] In the power supply system 10X, the switch SW and the current sensor CT are connected on the power grid side rather than at the node to the power meter 50 in the tie line. Thereby, the power supply system 10X can prevent reverse power flow by performing open control of the switch SW based on the current value of the current sensor CT.

[0213] When detecting reverse power flow, the central control device 60X performs output suppression control so that reverse power flow does not occur. The method of output suppression control is the same as that in the first embodiment.

[0214] FIG. 15 is a flowchart showing an example of power output control of the power supply system according to the sixth embodiment.

[0215] If the central control device 60X has not detected reverse power flow (S11x: NO), it performs normal power generation control on all the power conditioners 31-34.

[0216] When the central control device 60X detects reverse power flow (S11x: YES), it calculates the output suppression rate from the reverse power flow amount (S12x). The central control device 60X sets this output suppression rate as the output suppression rate of the power supply system 10X.

[0217] The central control device 60X centrally controls a plurality of power conditioners 31-34. More specifically, the central control device 60X performs normal power generation control on one power conditioner (S13). Further, the central control device 60X performs output suppression control on the remaining power conditioners other than the power conditioner performing normal power generation control (S14).

[0218] At this time, the central control device 60X controls the output suppression of the remaining power conditioners so as to achieve the output suppression rate of the power supply system 10X.

[0219] The central control device 60X continues this state for a time period of a predetermined rotation cycle (for example, 30 minutes, 1 hour, etc.).

[0220] When the time of the rotation cycle has elapsed, the central control device 60X switches the power conditioner that performs normal power generation control (S15).

[0221] Thereafter, the central control device 60X repeats the above control until the command for output suppression is released.

[0222] By performing such control, even in the self-consumption type power supply system 10X, the central control device 60X can obtain the maximum output power of the plurality of power conditioners 31-34 even during output suppression. This maximum output power is based on the environment at the time when output suppression is being performed.

[0223] Therefore, the central control device 60X can obtain the maximum output power of the plurality of power conditioners 31-34 in real time during output suppression.

[0224] In addition, since the central control device 60X grasps the suppression rate of each power conditioner performing output suppression, it can obtain the output power (suppressed output power) of each power conditioner performing output suppression.

[0225] In this way, the central control device 60X obtains the maximum output power and the suppressed output power of the plurality of power conditioners 31-34 during the period in which it has received the command for output suppression.

[0226] The central control device 60X calculates the difference value between the maximum output power and the suppressed output power for each of the plurality of power conditioners 31-34. Thereby, the central control device 60X can calculate the power that could not be output (generated) due to output suppression (loss power due to suppression command).

[0227] Note that the configurations and controls of the above-described embodiments can be combined as appropriate, and the combined effects can be achieved.

[0228] Also, the above-described distribution of output suppression is an example, and can be appropriately changed within the scope of the technical idea shown in each embodiment.

[0229] <1> A plurality of solar panels, A plurality of power conditioners each connected to the plurality of solar panels, A collector box that bundles the output power of the plurality of power conditioners, A load that is connected to the plurality of power conditioners via the collector box and is linked to the commercial power system, A central control device that centrally controls the operations of the plurality of power conditioners, Comprising, A power supply system of the all-power-sale type that supplies the output power of the plurality of power conditioners to the load and can perform reverse power flow to the commercial power system, The central control device, When receiving a command for output suppression, acquires the output suppression rate of the system, Among the plurality of power conditioners, at least one is set to normal power generation control without applying output suppression, The remaining power conditioners are set to output suppression control so as to achieve the output suppression rate of the system, The power conditioner to be subjected to the normal power generation control is sequentially switched in a rotation system, A power supply system, characterized by the above.

[0230] <2> A plurality of solar panels, A plurality of power conditioners each connected to the plurality of solar panels, A power collection box that bundles the output power of the plurality of power conditioners, A load that is connected to the plurality of power conditioners via the power collection box and is linked to the commercial power system, A central control device that centrally controls the operation of the plurality of power conditioners, Comprising, A self-consumption type power supply system that supplies the output power of the plurality of power conditioners to the load and makes reverse power flow to the commercial power system impossible, The central control device, When detecting the possibility of reverse power flow, calculates the output suppression rate of the system as a whole, Among the plurality of power conditioners, at least one is set to normal power generation control without output suppression, The remaining power conditioners are subjected to output suppression control so as to achieve the output suppression rate of the system as a whole, Sequentially switches the power conditioner to be subjected to the normal power generation control in a rotation system, A power supply system characterized by the above.

[0231] <3> The central control device, With respect to the output suppression rate of the system as a whole, Among the plurality of power conditioners, at least one is set to the normal power generation control, The remaining power conditioners are subjected to output suppression control so as to equally share the output power, The power supply system according to <1> or <2>, characterized by the above.

[0232] <4> The central control device, With respect to the output suppression rate of the system as a whole, Among the plurality of power conditioners, at least one is set to the normal power generation control, Among the remaining power conditioners, at least one is characterized by stopping operation. The power supply system according to <1> or <2>, characterized in that...

[0233] <5> The central control device When it detects that the output of the power conditioner for normal power generation control is equal to or less than a predetermined threshold value with respect to the output suppression rate of the system it determines that the power conditioner for normal power generation control is malfunctioning. The power supply system according to any one of <1> to <4>, characterized in that...

[0234] <6> The central control device By the control of the rotation system, for each of the plurality of power conditioners, it calculates the power difference between the actual output power in the normal power generation control and the output power after suppression and calculates the economic loss value based on the power differences of the plurality of power conditioners. The power supply system according to any one of <1> to <5>, characterized in that...

Explanation of Reference Numerals

[0235] 10, 10X: Power supply system 21 - 24: Solar panel 31 - 34: Power conditioner (PCS) 40: Collector box 50: Electric power meter 60, 60X: Central control device 90: Load CT: Current sensor SW: Switch

Claims

1. A plurality of solar panels, A plurality of power conditioners each connected to the plurality of solar panels, A power collection box for bundling the output power of the plurality of power conditioners, A load connected to the plurality of power conditioners via the power collection box and linked to a commercial power system, A central control device for centrally controlling the operation of the plurality of power conditioners, Comprising, A power supply system of the all-power-sale type capable of supplying the output power of the plurality of power conditioners to the load and performing reverse power flow to the commercial power system, The central control device, When receiving a command for output suppression, acquires the output suppression rate of the system as a whole, Among the plurality of power conditioners, at least one is set to normal power generation control without applying output suppression, The remaining power conditioners are subjected to output suppression control so as to achieve the output suppression rate of the system as a whole, The power conditioner to be subjected to the normal power generation control is sequentially switched in a rotation system, A power supply system, characterized in that.

2. A plurality of solar panels, A plurality of power conditioners each connected to the plurality of solar panels, A power collection box for bundling the output power of the plurality of power conditioners, A load connected to the plurality of power conditioners via the power collection box and linked to a commercial power system, A central control device for centrally controlling the operation of the plurality of power conditioners, Comprising, A self-consumption type power supply system that supplies the output power of the plurality of power conditioners to the load and makes reverse power flow to the commercial power system impossible, The central control device, When detecting the possibility of occurrence of reverse power flow, calculates the output suppression rate of the system as a whole, Among the plurality of power conditioners, at least one is set to normal power generation control without applying output suppression, The remaining power conditioners are subjected to output suppression control so as to achieve the output suppression rate of the system as a whole, The power conditioner to be subjected to the normal power generation control is sequentially switched in a rotation system, A power supply system, characterized in that.

3. The central control device, With respect to the output suppression rate of the system as a whole, Among the plurality of power conditioners, at least one is set to the normal power generation control, The remaining power conditioners are subjected to output suppression control so as to equally share the output power, The power supply system according to claim 1 or claim 2, characterized in that...

4. The central control device With respect to the output suppression rate of the system, Among the plurality of power conditioners, at least one performs the normal power generation control, Among the remaining power conditioners, at least one stops operating, characterized in that... The power supply system according to claim 1 or claim 2, characterized in that...

5. The central control device With respect to the output suppression rate of the system, When it detects that the output of the power conditioner to be subjected to the normal power generation control is equal to or less than a predetermined threshold value, it determines that the power conditioner to be subjected to the normal power generation control has failed. The power supply system according to claim 1 or claim 2, characterized in that...

6. The central control device By the control of the rotation system, for each of the plurality of power conditioners, calculates the power difference between the actual output power in the normal power generation control and the output power after suppression, Calculates the economic loss value based on the power differences of the plurality of power conditioners. The power supply system according to claim 1 or claim 2, characterized in that...

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