JP2023183590A - Output controller, output control program, and photovoltaic home consumption system based on the same - Google Patents

Abstract

To provide a photovoltaic power generation system with multiple PCSs which reduces occurrence of a reverse power flow.SOLUTION: An output controller 2 comprises: power consumption measuring means, where the total of the output power of multiple PCSs 3 and the received power is regarded as the power consumed; control command value transmitting means which prioritizes the multiple PCSs 3 and transmits, to the PCSs 3 in the order of the priority, control command values to define upper limit values of the output power; control target value calculating means to calculate a control target value to define an upper limit value when the output power of the multiple PCSs 3 is totaled; and control command value calculating means to calculate the control command value for each PCS 3 such that the upper limit value of the output power at the PCS 3 decreases with increasing priority, on the basis of the control target value calculated by the control target value calculating means.SELECTED DRAWING: Figure 1

Description

The present invention relates to an output control device and an output control program for a power conditioner used in a system for self-consuming power generated by solar cells, and more specifically to output control for preventing generation of reverse power flow. It relates to a device and an output control program.

Patent Document 1 describes an output control device and an output control program for preventing generation of reverse power flow. The solar power generation self-consumption system (1) described in Patent Document 1 (the code in parentheses is the code described in the patent document. The same applies hereinafter) includes a solar cell (2) and a power conditioner (3). , a power receiving and transforming facility (5), and an output control device (4) for controlling the output power of the power conditioner (3). The output control device (4) has a storage unit (42) that stores a ratio/setting difference value table registered in advance as a setting difference value (β) in correspondence with the ratio (α) between power consumption and PCS rating. Then, refer to the ratio/setting difference value table, determine the setting difference value (β) corresponding to the ratio (α), and subtract the determined setting difference value (β) from the current power consumption. It is provided with a control unit (41) that controls the output of the power conditioner 3 by dividing it by the PCS rating and using the divided value as a control command value (A).

Note that a plurality of loads are generally used as the load. If you want to measure the power consumption of each load, you will need to install a wattmeter, ammeter, etc. on each load. This is often difficult to achieve due to cost considerations. Therefore, in a self-consumption system, the power consumption is generally the sum of the power received from the commercial power system and the output power of the power conditioner (power generated by the solar cell).

Conventionally, in a solar power generation system for self-consumption, when controlling the output of a power conditioner (hereinafter referred to as "PCS"), an output control device sends a control command value to the PCS. and was in control. For example, the control command value is a numerical value indicating what percentage of the PCS rating (maximum output power of the PCS) is set as the upper limit value. For example, if an output control device sends a control command value of 60% to a PCS with a PCS rating of 10 kW, the PCS will set the upper limit of output power to 6 kW, and output the power generated by the solar cell. Control output. In addition, as the control command value used for controlling the PCS, the number of kW of output power may be directly used instead of using a percentage of the PCS rating, and any well-known method can be used as the control command value for the PCS. is used (the same applies hereafter). The control command value is a value for specifying the upper limit value of the output power of the PCS.

Here, a case where a plurality of PCSs exist will be described. In a conventional general self-consumption system, when a plurality of PCSs exist, the same control command value is uniformly transmitted to the plurality of PCSs. Hereinafter, such control will be referred to as "equal division control."

A specific example will be explained using FIG. 11. As shown in the left diagram of FIG. 11, when controlling the PCS using "equal division control", for example, the output control device transmits the control command value as determined in Patent Document 1 to all the PCS. It happens. For example, if there are five PCSs with a PCS rating of 10 kW, a control command value of 80% is transmitted to all five PCSs. Then, the upper limit of the output power of the five PCSs will be limited to 8 kW, which is 80% of 10 kW. Therefore, as shown in FIG. 11, the total maximum output power of the five PCSs is 40 kW.

Conventionally, when a plurality of PCSs exist, reverse power flow has been prevented by controlling the upper limit of the output power of the PCSs through such equal division control.

Patent No. 7004987 JP 2021-191162 Publication

However, the output control device and the PCS are generally connected through serial communication such as RS-485. Therefore, a signal is sent from the output control device to the first PCS to control the output power (also referred to as generated power. The same applies hereinafter) of the first PCS, and then a signal is sent to the second PCS. Then, the output power of the second PCS is controlled, and so on, and finally, a signal is transmitted to the n-th PCS to control the output power of the n-th PCS.

In FIG. 12, it is assumed that 80% of the output command value is sequentially transmitted from PCS1 to PCS5 by serial communication using equal division control. As shown in FIG. 12, while control is being performed between the output control device and the plurality of PCSs, the power consumption suddenly decreases, and the generated power cannot be controlled in time, causing the generated power to decrease. There may be a surplus and a reverse power flow may occur.

In this case, as shown in the graph of Figure 12, from Step 1 to Step 5, the total value of the generated power of the five PCSs will gradually decrease in order, but the power consumption will be faster than the decreasing speed of the generated power. If it decreases quickly, a surplus of generated power will occur, causing a reverse power flow.

As described above, when controlling a plurality of PCSs with the same control command value using the conventional equal division control, there is a possibility that reverse power flow may occur depending on the situation.

Therefore, an object of the present invention is to provide an output control device and an output control program that make it difficult to generate reverse power flow in a solar power generation system using a plurality of PCSs.

Note that claim 1 of Patent Document 2 describes "a power generation control program characterized in that an interval of the power consumption acquisition step is shorter than an interval of the command transmission step."

As described above, it is not practical to measure the power consumption for each individual load, so in reality, the power consumption is the sum of the received power from the commercial power system and the generated power. As shown in FIG. 13, the generated power is sequentially reflected after the control command value is transmitted from the output control device to each PCS. Therefore, it takes one control cycle for the generated power of all the PCSs to be reflected as being based on the instructions of the control command value. Even if you try to calculate the target value for controlling the PCS (control target value) when one control cycle is not completed, the generated power and received power may not be reflected correctly because the change is still in progress. Become.

Therefore, as claimed in claim 1 of Patent Document 2, "a power generation control program characterized in that the interval of the power consumption acquisition step is shorter than the interval of the command transmission step", based on incorrect power consumption, The control target value will be determined. Therefore, with such a program, the expected effects cannot be obtained.

Next, FIG. 4 and paragraphs 0053 to 0059 of Patent Document 2 describe control of a plurality of PCSs. In these descriptions, for example, ``When the upper limit value of the total generated power is reduced to 35 kW at time t1, the measurement control terminal 6 uses the PCS 3, which is one of the power generation control devices 2 that outputs the maximum power output value of 20 kW. The measurement control terminal 6 selects the PCS 4, which is one of the other power generation control devices 2, and commands it to output 20kW of power. In addition, the other power generation control devices 2 are instructed to output power of 0 kW.''

That is, in Patent Document 2, first, a PCS with a large maximum output power (corresponding to the PCS rating) is selected with respect to the total generated power upper limit value (corresponding to the control target value), and then, for that PCS, An algorithm for transmitting control command values is adopted (claim 4 of Patent Document 2 also has the same effect).

Note that claim 1 of Patent Document 2 states, "a command transmitting step of selectively transmitting a control command value only to some of the power generation control devices," and the control command value is transmitted only to selected PCSs. On the other hand, in the statement in the above specification, it is stated that 0 kW is commanded to the PCS that sets the amount of generated power to 0 kW, and there is a contradictory statement between the claim and the specification. Yes, but I'll leave that point out.

In any case, in Patent Document 2, the PCS having the maximum output power is selected, and the output power from the PCS is controlled to be as large as possible. However, in the case of such control, the speed at which the generated power decreases from the start of the control is slow, as in the case of the equal division control shown in FIG. 12.

For example, it is understandable that at time t1 in FIG. 4 of Patent Document 2, if the PCS3 is controlled to 20kW and then the PCS4 is controlled to be 15kW, the speed of decrease in the total generated power will be gradual. Probably. In this way, if the power consumption suddenly decreases in a situation where the rate of decrease is slow, a surplus of generated power will occur, and a reverse power flow will occur.

Therefore, the output control program described in Patent Document 2 cannot solve the problem of making it difficult to generate reverse power flow in a solar power generation system using a plurality of PCSs.

In order to solve the above problems, the present invention has the following features.
The present invention is an output control device for controlling the output power of a plurality of power conditioners connected to a solar cell, and the power consumption is the sum of the received power and the output power of the plurality of power conditioners. A control command that prioritizes a power measurement means and a plurality of power conditioners, and transmits a control command value for specifying an upper limit value of output power to the power conditioners in the order of priority. a value transmitting means; a control target value calculating means for calculating a control target value that defines an upper limit value when the output power of the plurality of power conditioners is summed; and a control target value calculating means based on the control target value calculated by the control target value calculating means. , a control command value calculation means for calculating a control command value to each power conditioner such that the upper limit value of the output power of the power conditioner becomes lower in order of priority.

Preferably, the control command value calculation means uses a control command value such that the upper limit value of the output power of the power conditioner is 0 according to the priority order.

Preferably, the output control device further includes a suppressed power calculation means that calculates, as suppressed power, a sum of upper limit values when output power of the plurality of power conditioners is suppressed based on the control target value. The control command value calculation means is configured to calculate, while the sum of the PCS ratings of the power conditioner using the control command values such that the upper limit value of the output power is equal to or less than the suppressed power, the control command value whose upper limit value is 0 is used. good.

Preferably, the control command value calculation means calculates a control command value for a power conditioner other than a power conditioner using a control command value for which the upper limit value of output power is 0, so that the upper limit value is greater than 0. It's good to do that.

Preferably, the control command value calculation means uses a control command value that enables the remaining power conditioners to generate power up to the PCS rating.

Preferably, the control target value calculation means calculates a ratio between power consumption and a total PCS rating, which is the sum of PCS ratings of a plurality of power conditioners, and calculates a set difference value stored corresponding to the ratio. Determine the setting difference value corresponding to the calculated ratio by referring to the table showing It is good to decide.

Preferably, the sum of the upper limit values of the output power of the plurality of power conditioners specified by the control command value corresponds to the sum of the upper limit value of the output power of the plurality of power conditioners specified by the control target value. Good to have.

Preferably, the priority order should be changed on a daily basis.

The present invention also provides an output control device for controlling output power of a plurality of power conditioners connected to a solar cell, in which the sum of received power and output power of the plurality of power conditioners is defined as power consumption. A power consumption measuring means for determining power consumption and a plurality of power conditioners are prioritized, and a control command value for specifying the upper limit of output power is transmitted to the power conditioners in the order of priority. The power conditioner includes a control command value transmitting means and a control command value calculating means for calculating a control command value to each power conditioner so that the upper limit value of the output power of the power conditioner becomes lower in order of priority.

The present invention also provides an output control device for controlling output power of a plurality of power conditioners connected to a solar cell, in which the sum of received power and output power of the plurality of power conditioners is defined as power consumption. A power consumption measuring means for determining power consumption and a plurality of power conditioners are prioritized, and a control command value for specifying the upper limit of output power is transmitted to the power conditioners in the order of priority. A control command value transmitting means, a suppression power calculation means for calculating suppression power that defines the total value when the output power of a plurality of power conditioners is suppressed, and a suppression power calculation means that determines priority based on the suppression power calculated by the suppression power calculation means. A control command value calculating means is provided for calculating a control command value to be sent to each power conditioner so that the upper limit value of the output power of the power conditioner becomes lower in descending order of ranking.

Further, the present invention provides an output control device for controlling the output power of a plurality of power conditioners connected to a solar cell. power measurement means, a control command value that prioritizes a plurality of power conditioners, and transmits a control command value for specifying an upper limit value of output power to the power conditioners in the order of priority; Based on the transmitting means, the control target value calculating means for calculating the control target value that defines the upper limit value when the output power of the plurality of power conditioners is summed, and the control target value calculated by the control target value calculating means, This is an output control program for functioning as a control command value calculation means for calculating control command values for each power conditioner so that the upper limit value of the output power of the power conditioner becomes lower in order of priority.

Further, the present invention provides an output control device for controlling the output power of a plurality of power conditioners connected to a solar cell. power measurement means, a control command value that prioritizes a plurality of power conditioners, and transmits a control command value for specifying an upper limit value of output power to the power conditioners in the order of priority; An output for functioning as a transmitting means and a control command value calculation means for calculating control command values to each power conditioner so that the upper limit value of the output power of the power conditioner becomes lower in order of priority. It is a control program.

Further, the present invention provides an output control device for controlling the output power of a plurality of power conditioners connected to a solar cell. power measurement means, a control command value that prioritizes a plurality of power conditioners, and transmits a control command value for specifying an upper limit value of output power to the power conditioners in the order of priority; A transmission means, a suppression power calculation means that calculates suppression power that defines the total value when the output power of a plurality of power conditioners is suppressed, and a suppression power calculation means having a high priority based on the suppression power calculated by the suppression power calculation means. This is an output control program for functioning as a control command value calculation means for calculating control command values to each power conditioner so that the upper limit value of output power of the power conditioner becomes lower in order.

Further, the present invention provides a solar power generation system including a plurality of solar cells, a plurality of power conditioners connected to the plurality of solar cells, and an output control device for controlling output power of the plurality of power conditioners. The output control device includes a power consumption measuring means that determines the power consumption as the sum of the received power and the output power of the plurality of power conditioners, and a priority order of the plurality of power conditioners. control command value transmitting means for transmitting a control command value for specifying an upper limit value of output power to the power conditioner; A control target value calculation means for calculating a prescribed control target value, and a control target value calculated by the control target value calculation means, so that the upper limit value of the output power of the power conditioner becomes lower in order of priority. and a control command value calculation means for calculating a control command value for each power conditioner.

Further, the present invention provides a solar power generation system including a plurality of solar cells, a plurality of power conditioners connected to the plurality of solar cells, and an output control device for controlling output power of the plurality of power conditioners. The output control device includes a power consumption measuring means that determines the power consumption as the sum of the received power and the output power of the plurality of power conditioners, and a priority order of the plurality of power conditioners. control command value transmitting means for transmitting a control command value for specifying an upper limit value of output power to the power conditioner in order of priority; control command value calculation means for calculating a control command value for each power conditioner such that the power conditioner is low.

Further, the present invention provides a solar power generation system including a plurality of solar cells, a plurality of power conditioners connected to the plurality of solar cells, and an output control device for controlling output power of the plurality of power conditioners. The output control device includes a power consumption measuring means that determines the power consumption as the sum of the received power and the output power of the plurality of power conditioners, and a priority order of the plurality of power conditioners. control command value transmitting means for transmitting a control command value for specifying an upper limit value of output power to the power conditioner; Based on the suppressed power calculation means that calculates the specified suppressed power and the suppressed power calculated by the suppressed power calculation means, each power is set in descending order of priority so that the upper limit of the output power of the power conditioner becomes lower. and control command value calculation means for calculating a control command value to the conditioner.

According to the present invention, the control commands are calculated so that the upper limit value of the output power of the power conditioner becomes lower in order of priority. You can lower it all at once. Therefore, in a solar power generation system using a plurality of PCSs, it is possible to make it difficult for reverse power flow to occur.

If a control command value with which the upper limit value of the output power of the power conditioner is 0 is used according to the priority order, the output power can be lowered at once in the first stage of control.

Processing that uses a control command value that makes the upper limit of the output power of the power conditioner 0 is performed when the sum of the PCS ratings of the power conditioner that uses the control command value that makes the upper limit of the output power 0 is less than or equal to the suppressed power By performing this for a period of time, it becomes possible to suppress the generated power by the amount of suppressed power at once in the early stage of one control cycle.

Then, by calculating the control command values of power conditioners other than the power conditioner using the control command value whose upper limit value of output power is 0, so that the upper limit value is larger than 0, all power conditioners It is possible to adjust the total value of the output power of the four elements to a value based on the control target value.

Finally, by using a control command value that allows the remaining power conditioners to generate output power up to the PCS rating, the remaining power conditioners can be easily controlled and the overall power generation efficiency is improved.

In this way, in one control cycle, the output power of the first power conditioner with higher priority is set to 0, and the power conditioner is changed so that the total value of output power is a value based on the control target value. By adjusting the value of the output power of and generating the remaining power up to the PCS rating, it is possible to avoid reverse power flow due to a sudden drop in power consumption and increase power generation efficiency.

When calculating the control target value, load equalization control uses an easy-to-understand table called the ratio/setting difference value table, which allows you to set the avoidance of reverse power flow, making power conditioner control easy to understand. can be taken as a thing. In addition, compared to arithmetic control that uses differential values that are uniformly the same, the set differential value can be determined according to the ratio between power consumption and PCS rating, so there is more margin in the upper limit of generated power. Compared to geometric control, the upper limit value of generated power can be set higher while avoiding reverse power flow, making it possible to utilize the generated power of the solar cells as effectively as possible.

By changing the priority order on a daily basis, it is possible to prevent some power conditioners from being overloaded.

These and other objects, features, aspects, and advantages of the present invention will become more apparent from the following detailed description when considered in conjunction with the accompanying drawings.

FIG. 1 is a block diagram showing the functional configuration of a solar power generation system 1 in an embodiment of the present invention. FIG. 2 is a flowchart showing the operation of the output control device 2 when the output control program is executed. FIG. 3 is a conceptual diagram showing the flow of processing in one control cycle. FIG. 4 is a flowchart showing the control target value calculation process in FIG. FIG. 5 is a diagram showing an example of a ratio/setting difference value table. FIG. 6 is a flowchart showing the process of calculating control command values for each PCS in FIG. 2. FIG. 7 is a diagram showing an example of specific numerical values when the operation of FIG. 6 is followed. FIG. 8 is a flowchart showing another example of the control command value calculation process for each PCS in FIG. 2. FIG. 9 is a diagram showing an example of specific numerical values when the operation of FIG. 8 is followed. FIG. 10 is a diagram showing an example of specific numerical values in another example of the control command value calculation process for each PCS in FIG. 2. FIG. 11 is a diagram comparing the outlines of conventional equal division control and priority control of the present invention. FIG. 12 is a diagram comparing the problems of conventional equal division control and the effects of priority control of the present invention. FIG. 13 is a diagram showing the transition of generated power and received power in one control cycle in conventional equal division control.

First, using FIG. 11, a general comparison will be made between the conventional equal division control and the control of the present invention (hereinafter referred to as "priority control").
As shown in the right diagram of FIG. 11, in priority control, for example, it is assumed that for five PCSs with a PCS rating of 10 kW, the total PCS rating, which is the sum of all PCS ratings, is to be 80%. In FIG. 11, the control command value (corresponding to a "control target value" described later) is shown as 80%.
At this time, instead of setting each PCS to 80% as in equal division control, first, control command value is set for one PCS to be controlled preferentially (hereinafter referred to as "priority PCS") Send 0% as . As a result, the maximum output of the five PCSs becomes 40kW, making the total PCS rating 80% and achieving the purpose. In this way, in the priority control, the generated power is initially suppressed at once, so that the generated power can be quickly reduced.

Note that if the priority PCS is always the same, there is a possibility that too much load will be placed on a specific PCS, so it is preferable that the priority PCS changes automatically according to a predetermined rule. For example, the priority PCS may be changed depending on the date and time, or the priority PCS may be changed randomly, and the method of changing the priority PCS is not limited to the present invention. In the present invention, it is sufficient that the order of PCSs to be controlled preferentially is determined in advance.

As shown in FIG. 12, in Step 1, it is assumed that a control command value of 0 [%] is transmitted to the PCS 1 to immediately reduce the power generated by the PCS 1. Thereafter, a control command value of 100[%] is transmitted to the remaining PCSs 2 to 5. As a result, as shown in the graph of FIG. 12, the generated power suddenly decreases at the first Step 1. Therefore, even if power consumption changes suddenly, the possibility of reverse power flow occurring can be avoided.

An embodiment for realizing the above outline will be described below with reference to FIGS. 1 to 10.

In FIG. 1 , a solar power generation system 1 includes an output control device 2 , a plurality of PCSs 3 , a plurality of solar cells 4 , an RPR (Reverse Power Relay) 5 , and power receiving and transforming equipment 6 . A power transmission and distribution network 7 is connected to the power receiving and transforming equipment 6 via an RPR 5 . The power receiving and transforming equipment 6 supplies received power from a commercial power system to a plurality of loads 8 . The power receiving and transforming equipment 6 transmits a received power signal indicating the value [kW] of received power to the output control device 2 . Note that here, the power receiving and transforming equipment 6 is configured to transmit a power receiving signal to the output control device 2, but a measuring instrument for the received power is installed separately from the power receiving equipment 6, and the measuring instrument controls the output of the received power. It may also be transmitted to the device 2. In any case, the output control device 2 is capable of detecting the received power.

The output control device 2 is a computer device, and includes an input section, an output section, a communication section, a storage section, and a control section. The storage unit stores an output control program, and the control unit executes the output control program. Further, the storage unit stores a comparison/setting difference value table, which will be described later, as in Patent Document 1.

Here, it is assumed that the output control device 2 and each PCS 3 communicate with each other through serial communication such as RS-485. However, the present invention is not limited to such serial communication, and may be Ethernet (registered trademark) communication or other communication methods.

In the example shown in FIG. 1, the output control device 2 and each PCS 3 are connected by a multi-drop connection in which devices are connected in a cascading manner on a cable, but the connection method is not limited to this. Any known method can be used.

A destination address is attached to the signal sent from the output control device 2 to each PCS 3, and processing is executed by the PCS 3 corresponding to the destination address responding to the signal from the output control device 2. The Rukoto.

A solar cell 4 is connected to each PCS 3. Each PCS 3 can control the output power by controlling the power generated by the solar cell 4 (power output from the solar cell 4) using any known method.

Each PCS 3 is connected to power receiving and transforming equipment 6. The generated power from each PCS 3 is supplied to each load 8 along with the received power via the power receiving and transforming equipment 6.
If reverse power flow is detected by RPR5, RPR5 instructs each PCS3 to stop power generation. Thereby, the output power from each PCS 3 is cut off from being supplied to the power receiving and transforming equipment 6, and reverse power flow is prevented. When the RPR 5 is activated and the power generation of the PCS 3 is stopped, the power generated by the solar cell 4 is wasted. Therefore, in the private consumption system, it is necessary to prevent the RPR5 from operating as much as possible, that is, to prevent reverse power flow from occurring. Note that the installation position and operating method of the RPR do not limit the present invention. Further, RPR is not an essential configuration of the present invention.

The operation of the output control device 2 executing the output control program will be described with reference to FIG. 2.

First, the output control device 2 acquires a received power signal from the power receiving and transforming equipment 6 and recognizes the received power from the commercial power system (S10).

Next, the output control device 2 requests the first PCS to transmit a generated power signal (S11). Here, the generated power signal is a signal indicating how many kW of generated power is. In response, the first PCS returns the generated power signal to the output control device 2, and the output control device 2 receives the generated power signal (S12). Next, the output control device 2 transmits the control command value for the first PCS calculated in the previous control cycle to the first PCS (S13: control command value transmitting means), and controls from the first PCS. A response indicating that the command value has been received is received (S14). As a result, the output power of the first PCS is controlled. Note that the output power of the first PCS can be acquired and recognized by the output control device 2 in the next control cycle.

In addition, in the case of a predetermined situation such as at the time of initial startup, the output control device 2 transmits 0% as the control command value to each PCS 3. At the time of initial startup, the power consumption is not determined because the generated power is not known, so the control command value for each PCS 3 is set to 0% for safety so that reverse power flow does not occur.

Note that here, the control command value is a value indicating a percentage of the PCS rating, but the format of the control command value does not limit the present invention, and it is sufficient to use the control command value specified by the PCS3. .

Here, the first to nth PCSs will be explained. In the present invention, the PCS 3 is given a priority order of control. Various methods can be considered for assigning priorities; for example, a method may be considered in which PCS3, which has the highest priority, is changed every day. The first PCS is PCS3 with priority number 1, the second PCS is PCS3 with priority number 2, and similarly, the nth PCS is PCS3 with priority number n.

Let's explain with an example.
Let PCS3, which has the highest priority today, be PCS-1. The PCS3 with the second priority is designated as PCS-2. Similarly, the PCS3 with the nth priority is designated as PCS-n. In this case, today's output control is for the first to nth PCSs in the order of PCS-1, PCS-2, . . . , PCS-n, and the processing proceeds according to the operation flow shown in FIG.

If only the same PCS3 is given high priority, the same PCS3 may be overloaded and a problem may occur. Therefore, it is possible to adopt a method of changing the priority order the next day. In this case, for example, PCS3 having the highest priority is set as PCS-2. The PCS3 with the second priority is designated as PCS-3. Similarly, the PCS3 having priority number n-1 is designated as PCS-n. The PCS3 with the nth priority is designated as PCS-1.

In this way, it is preferable that the priority order of the PCS 3 changes according to a predetermined rule, such as daily or weekly. However, in the present invention, changing the priority order of the PCS 3 is not an essential configuration, and the priority order may be fixed.

The priority order of PCS3 may be determined randomly or by other predetermined rules, or PCS3 with a high PCS rating may be set as a high priority PCS, or PCS3 with a low PCS rating may be determined as a PCS3 with a high priority. may be set as a PCS with a high priority, or the priority may be determined in order of manufacturing date, or the priority may be determined based on the magnitude of past generated power.

Returning to the explanation of FIG. 2, we will return to the explanation of FIG. 2 on the premise that the first to nth PCSs have been determined in such a priority order.

After S14, for the second PCS, a request for transmission of generated power (S15), reception of a generated power signal (S16), transmission of a control command value (S17: control command value transmission means), and reception of a response (S18) are performed. ) is carried out. Thereafter, similar processing is performed up to the n-th PCS (S19, S20, S21 (control command value transmitting means), S22).

Through the processing up to S22, the received power and the generated power of each PCS 3 (the generated power generated based on the control command value in the previous control cycle) have been acquired.

Through the control target value calculation process (control target value calculation means) in S23, the output control device 2 calculates the sum of the upper limit values of the output power of each PCS 3 (hereinafter referred to as "total output power target value") of each PCS 3. Determine what percentage of the total PCS rating (hereinafter referred to as "total PCS rating"). This determined percentage is called a control target value.
That is, control target value=total output power target value/PCS total rating×100 [%].

Note that the method of determining the control target value is just an example, and does not limit the present invention. The control target value is a value defined by the sum of the upper limit values of the output power of each PCS3.

In S23, after the control target value is calculated, the output control device 2 calculates a control command value to each PCS 3 (S24: control command value calculation means).

Here, one cycle of control by the output control device 2 will be summarized using FIG. 3. As shown in FIG. 3, during one control cycle, the output control device 2 measures received power, measures generated power of the first PCS, transmits a control command value to the first PCS, etc. Measures the power generated by the n-th PCS, sends a control command value to the n-th PCS, calculates a control target value, and calculates a control command value to each PCS.

As shown in FIG. 3, each PCS receives a control command value from the output control device 2 and then controls the output power. Since a certain amount of time is required to control the output power, the results of controlling the output of each PCS3 based on the control command value transmitted in one control cycle are reflected in the following This is one cycle of control. Then, in the next control cycle, the output control based on the control command value instructed in the previous control cycle is reflected, and the output control device 2 executes the next output control, and repeats this cycle. It is.

The control target value calculation process will be explained using FIGS. 4 and 5. Note that the operations shown in FIGS. 4 and 5 have the same gist as the operations described in Patent Document 1.

The output control device 2 sums the received power acquired in S10 and the total generated power of the PCS acquired in S12, S16, ..., S20 (hereinafter referred to as "PCS total generated power"). It is defined as power consumption (S31: power consumption measuring means).

Next, the output control device 2 calculates the power consumption/PCS total rating and calculates the ratio α between the power consumption and the PCS total rating (S32).

The output control device 2 stores a ratio/setting difference value table in which a setting difference value β [kW] is defined in correspondence with the ratio α. FIG. 5 is an example of a ratio/setting difference value table. As shown in FIG. 5, a set difference value β [kW] is determined for the ratio α. The control target value is determined based on the value obtained by subtracting the set difference value β from the power consumption. For example, as shown in FIG. 5, the larger the ratio α, the larger the set difference value β. As a result, even if power consumption suddenly decreases in a region where power consumption is large, there will be a margin in the set difference value β, so the generated power will exceed the consumed power and reverse power flow will occur. It is possible to avoid the situation.

If the ratio α is larger than 100 [%], the power consumption exceeds the PCS rating, so I think it is okay to generate the maximum amount of power, but if the power consumption suddenly decreases, the maximum power generation is possible. If this occurs, the power conditioner control may not be able to keep up, resulting in reverse power flow or RPR operation. Therefore, even if the ratio α is larger than 100%, it is preferable to set the set difference value with a safety margin in mind.

After S32, the output control device 2 refers to the ratio/setting difference value table and determines the setting difference value β corresponding to the ratio α (S33). The output control device 4 determines whether the power consumption-setting difference value β is less than or equal to 0 (S34). If it is determined in the operation of S34 that the power consumption-setting difference value β is less than or equal to 0, the output control device 4 sets the control target value to 0 (S36).

On the other hand, in the operation of S34, if it is determined that the power consumption-setting difference value β is larger than 0, the output control device 4 proceeds to the operation of S35. In S35, the output control device 4 calculates (power consumption - set difference value β)/PCS total rating, and uses the calculation result as the control target value. The control target value means the percentage of the total PCS rating that the entire PCS can output power to. The present invention is not limited to whether the control target value is expressed as a percentage or as a numerical value using a decimal point. The control target value is a value for controlling the total value of the upper limit values of the output power of each PCS3.

However, if the calculation result is 1 or more, that is, if the power consumption-setting difference value β is greater than or equal to the PCS total rating, the output control device 4 sets the control target value to 1. If the calculation result is 1 or more, it means that the power consumption is sufficiently large, and it means that there is a high possibility that reverse power flow will not occur even if all the PCSs output their maximum output.

The output control device 2 executes the operation shown in FIG. 3 for each control cycle, always calculates the control target value according to the latest power consumption, and transmits the latest control command value to each PCS 3. do. In response to this, each PCS 3 outputs power according to the latest power consumption.

Next, the control command value calculation process for each PCS 3 will be explained using FIGS. 6 and 7. As shown in FIG. 6, the output control device 2 calculates PCS total rating - PCS total rating x control target value, and sets the calculation result as "suppression power" (STEP 1: suppression power calculation means). Note that the way to define the suppressed power is not limited to the above, including formula modifications. Furthermore, here, the suppression power is calculated using the control target value, but the suppression power may be calculated directly without using the control target value.

Next, in STEP 2, the output control device 2 reduces the PCS rating of the PCS having the PCS number given priority on the current day from the suppressed power or surplus. Note that the suppressed power is used in the first STEP 2, and the surplus is used in the second and subsequent STEP 2. The first PCS corresponds to the PCS number at the first STEP 2. From STEP 2 for the second time onward, the second PCS to the nth PCS correspond to the PCS number.

If there is a surplus in the subtracted value, the control command value of the PCS having the PCS number with priority on that day is set to 0 [%].

If there is no surplus in the reduced value, (PCS rating - suppressed power (or surplus))/PCS rating of the day's priority PCS number x 100 [%] is set as the control command value of the day's priority PCS number. Note that the control command value may not be expressed as a percentage, but may be expressed as a number using a decimal point. In addition, in the above calculation formula, the suppressed power is used in the first STEP 2, and the surplus is used in the second and subsequent STEP 2.

The output control device 2 further determines whether there is a surplus in the value subtracted in STEP 2 (STEP 3). If there is still a surplus, the output control device 2 returns to the operation of STEP 2 and calculates the control command value for the PCS whose PCS number is "Today's priority PCS number + 1" in order to increment the current day's priority PCS number. Note that if the current day's priority PCS number +1 exceeds the number of equipment, the system returns to the first PSC.

On the other hand, if there is no surplus, the output control device 2 sets the control command value of the remaining PCS 3 to 100 [%].

A specific example of the process shown in FIG. 6 will be described using FIG. 7.

For example, if there are 5 PCSs, the PCS ratings of each PCS number are 10 [kW] for No. 1, 20 [kW] for No. 2, 30 [kW] for No. 3, 10 [kW] for No. 4, and 30 [kW] for No. 5. kW]. In this case, the total PCS rating is 100 [kW]. Assume that the first priority PCS number on that day is No.4. Assume that the control target value is 65% as a result of calculation.

In STEP 1, the suppression power becomes 35 [kW] by calculating the PCS total rating of 100 kW x (1 - control target value 65 [%]). Needless to say, during calculation, the control target value 65 [%] is calculated using a decimal point.

In STEP 2-1 (referring to the first STEP 2; the same applies hereinafter), the surplus becomes 25 [kW] from the calculation of suppressed power 35 [kW] - No. 4 PCS rating 10 [kW]. Therefore, since there is a surplus, the control command value of No. 4 becomes 0 [%]. By STEP 2-1, the PCS rating of No. 4 of 10 [kW] is quickly suppressed (see also the lower diagram of FIG. 7).

In STEP 2-2, the surplus becomes 0 [kW] by calculating the surplus 25 [kW] - No. 5's PCS rating of 30 [kW]. Therefore, since there is no surplus, the control command value for No. 5 is 16.6...[ %]. By STEP 2-2, the generated power of No. 5 is suppressed by 25 [kW] (see also the lower diagram of FIG. 7).

Since there is no further surplus, the control command values for Nos. 1, 2, and 3 become 100% in STEP 5 (see also the lower diagram in FIG. 7).

In this way, in the example shown in FIG. 7, the suppressed power of 35 [kW] is preferentially suppressed from the output power of all PCS3, so that the power consumption sharply decreases during one control cycle. This can prevent reverse power flow from occurring. Note that the total of the upper limit values of the output power of all the PCSs 3 (shown as maximum output; defined by the control target value) is 65 [kW].

Another example of the control command value calculation process for each PCS in FIG. 2 will be described using FIGS. 8 and 9. In FIG. 8, the operation that is different from that shown in FIG. 6 is STEP2 and STEP3. The other STEPs are the same as the operations shown in FIG. 6, so the explanation will be omitted.

In STEP 2 of FIG. 8, the output control device 2 subtracts the PCS rating of the PCS having the PCS number given priority on that day from the suppressed power or surplus. Note that the suppressed power is used in the first STEP 2, and the surplus is used in the second and subsequent STEP 2. The method of determining the first to nth PCSs is the same as in the case of FIG.

If the quotient is 1 or more, the control command value of the PCS having the PCS number with priority on that day is set to 0 [%].

If the quotient is less than 1, (1 - quotient of division) x 100 [%] is set as the control command value for the current day's priority PCS number.

In STEP 3, it is determined whether the quotient is 1 or more. If it is less than 1, the process proceeds to STEP 4; if it is 1 or more, the process proceeds to STEP 5.

This will be explained in detail using FIG. 9. In FIG. 9, the conditions are the same as in the case of FIG. In STEP 1, the suppression power becomes 35 [kW] as in FIG. 7 .

In STEP 2-1, from the calculation of suppressed power 35 [kW]/PCS rating 10 [kW] of No. 4, the quotient is 3.5, so the control command value of No. 4 is 0 [%]. As a result, the PCS rating of No. 4 is suppressed by 10 [kW] (see also the lower diagram of FIG. 9).

In STEP 2-2, calculation of (suppression power 35 [kW] - PCS rating of No. 4 10 [kW])/PCS rating of No. 5 30 [kW] is performed. The number of the current day's priority PCS rating to be removed is incremented in STEP4. At this time, the quotient becomes 0.83... From the calculation of (1-0.83...)×100[%], the control command value for No. 5 is 16.6...[%]. As a result, 25 [kW] is suppressed, and a total of 35 [kW] is suppressed (see also the lower diagram of FIG. 9).

Finally, in STEP 5, the control command values of Nos. 1, 2, and 3 become 100% (see also the lower diagram of FIG. 9).

In this way, even in the example shown in FIG. 9, the suppressed power of 35 [kW] is preferentially suppressed from the output power of all PCS3, so that the power consumption sharply decreases during one control cycle. This can prevent reverse power flow from occurring. Note that the total of the upper limit values of the output power of all the PCSs 3 (shown as maximum output; defined by the control target value) is 65 [kW].

Another example of the control command value calculation process for each PCS in FIG. 2 will be described using FIG. 10.
FIG. 10 shows a case where processing is performed not sequentially from the current day's priority PCS number, but from the PCS with the highest rating (and the lowest PCS number). It is assumed that either FIG. 6 or FIG. 8 is used for the process of STEP 2. In FIG. 10, STEP 2 in FIG. 6 is used.

Similarly, in STEP 1, the suppression power of 35 [kW] is calculated.
In STEP 2-1, the PCS rating of No. 3 of 35 [kW] - 30 [kW] is calculated. Since the surplus is 5 [kW], the control command value of No. 3 is 0 [%].
In STEP 2-2, the surplus 5 [kW] - No. 5's PCS rating of 30 [kW] is calculated. Since the surplus is 0 [kW], the control command value of No. 5 is 83.3...[%].
Finally, in STEP 5, the control command values of Nos. 1, 2, and 4 are set to 100 [%].

In this way, even in the example shown in FIG. 10, the suppressed power of 35 [kW] is preferentially suppressed from the output power of all PCS3, so that the power consumption sharply decreases during one control cycle. This can prevent reverse power flow from occurring. Note that the total of the upper limit values of the output power of all the PCSs 3 (shown as maximum output; defined by the control target value) is 65 [kW]. Additionally, by prioritizing the PCS with a higher PCS rating, the output power can be significantly lowered at once in the first step, further preventing reverse power flow due to a sudden drop in power consumption during one control cycle. It becomes easier. Also, for example, if the PCS rating of No. 3 is 35 [kW] or more, the suppression power will be reached in the first step, so it is best to prioritize the one with a higher PCS rating. This is effective in that it further prevents reverse power flow due to a sudden drop in power consumption during a cycle.

Note that in the examples shown in FIGS. 6 to 10 above, the control command value of the first PCS is 0 [%], but depending on the numerical value, the control command value of the first PCS may be Needless to say, it may be larger than 0 [%].

As described above, in the above embodiment, while the sum of the PCS ratings of the PCS 3 using the control command value whose upper limit value of output power is 0 is equal to or less than the suppressed power, the control command whose upper limit value is 0 [%] Since the value is used to send control command values of 0% to the PCS3 in descending order of priority, the generated power can be lowered at once at the beginning of one control cycle, reducing the power consumption. This makes it possible to avoid reverse power flow due to a sudden decrease in Then, the output control device 2 calculates the control command value of the power conditioner other than the power conditioner using the control command value of 0 [%] so that it is larger than 0 [%], and outputs power. Adjust the upper limit value. For the remaining PCS3, a control command value that enables power generation up to the PCS rating is used.

In the above embodiment, the output control device 2 transmits a control command value to the PCS having the first priority to lower the output power at once. Thereafter, control command values for lowering the output power of the PCS are sequentially transmitted to the second PCS in accordance with the priority order. In this way, from the first stage of one control cycle, the output power of the high-priority PCS is lowered at once. This makes it possible to lower the total power generated by the PCS in one control cycle as quickly as possible at the first stage of one control cycle. Therefore, even if power consumption suddenly decreases during one control cycle, reverse power flow is less likely to occur.

As mentioned earlier, in Patent Document 2, an algorithm is adopted in which a PCS with a large PCS rating is selected and a control command value is transmitted to that PCS, but the control command value at that time is based on the PCS rating. The aim is to output as much power as possible from a large PCS.

However, the present invention reduces the power consumption within one control cycle by lowering the generated power as much as possible from the PCS with a high priority (depending on the setting, a PCS with a high PCS rating may have a high priority). This invention is used to prevent reverse power flow even if a sudden drop occurs.

That is, the invention described in Patent Document 2 and the present invention have opposite PCS control methods, and in the invention described in Patent Document 2, reverse power flow occurs when power consumption suddenly decreases. However, the present invention can avoid this possibility, and it can be said that the present invention is more suitable as an output control device for a private consumption system.

Note that in the above embodiment, in the process of S35, the control target value is defined as a ratio by (power consumption−setting difference value β)/PCS total rating. This is because the control command value for controlling the PSC uses a ratio to the PCS rating. If the power value is used as the control command value, the power consumption - setting difference value β can be used instead of (power consumption - setting difference value β) / PCS total rating as the control target value. . In that case, if the power consumption-setting difference value β is larger than the PCS total rating, the control target value becomes the PCS total rating.

In the above embodiment, in order to obtain the control target value, a method (referred to as "load equal difference control") of varying the set difference value β according to the ratio α of power consumption/PCS rating as shown in FIGS. 4 and 5 is used. ), however, in the present invention, the method of determining the control target value is not limited to load equal difference control.

For example, regarding the total PCS rating, there is a method in which the upper limit of the total output power of all PCSs is set to the value obtained by subtracting a predetermined power from the power consumption (referred to as "equal difference control"), or a method in which the power consumption is multiplied by a ratio. A method of setting the value as the upper limit of the total output power of all PCSs (referred to as "geometric control"), changing the value by which the power consumption is multiplied according to the ratio α, and setting the upper limit value of the total output power of all PCSs. The control target value may be determined using a method (referred to as "load equal ratio control").

Regardless of whether a ratio is used as the control target value or a power value is used as the control target value, calculation methods for determining the control target value include load equal difference control, equal difference control, equal ratio control, Even when using equal load ratio control or other methods, the control target value can be said to be a value that defines the upper limit value when the output power of all PCSs is totaled.

Then, when calculating the control command value to each PCS 3, the output control device 2 sends the output power to each PCS 3 based on the control target value so that the upper limit value of the output power in each PCS 3 becomes lower in order of priority. Calculate the control command value. At this time, the sum of the upper limit values of the output power in each PCS 3 based on the control command value to each PCS 3 corresponds to the upper limit value of the total output power of all PCS 3 defined by the control target value. The output control device 2 transmits the control command values calculated in this way to the PCS 3 in descending order of priority to control the output power of each PCS 3, starting from the PCS 3 with the highest priority. do.

In the above embodiment, it is assumed that PCS total rating−PCS total rating×control target value=suppression power. Therefore, it may be expressed as suppression power=PCS total rating×(1−control target value). In addition, other equivalent values may be used as the suppression power.

Further, control target value=(PCS total rating−suppression power)/PCS total rating=1−suppression power/PCS total rating. Other equivalent values may also be used for the control target value.

In addition, although the control command value is expressed using a percentage in the above, it goes without saying that it may be expressed using a decimal point. The control command value of 0 percent means that the upper limit value of the output power of the PCS 3 is 0 [kW]. A control command value of 100% means that the output power of the PCS 3 may be generated up to the PCS rating.

Although the present invention has been described in detail above, the above description is merely an illustration of the present invention in all respects, and is not intended to limit the scope thereof. It goes without saying that various improvements and modifications can be made without departing from the scope of the invention. The constituent elements of the invention disclosed in this specification shall each be established as an independent invention. Inventions in which each component is combined in any combination method are also included in the present invention.

INDUSTRIAL APPLICABILITY The present invention is an output control device, an output control program, and a solar self-consumption system using the same, and is industrially applicable.

1 Solar power generation system 2 Output control device 3 PCS
4 Solar cells 5 RPR
6 Power receiving and transforming equipment 7 Power transmission and distribution network 8 Load S31 Power consumption measuring means S13, S17, S21 Control command value transmitting means S23 Control target value calculating means S24 Control command value calculating means STEP1 Suppression power calculating means

Claims (16)

An output control device for controlling output power of a plurality of power conditioners connected to a solar cell,
a power consumption measuring means that determines the power consumption as the sum of the received power and the output power of the plurality of power conditioners;
A control command value that prioritizes the plurality of power conditioners, and transmits a control command value for defining an upper limit value of the output power to the power conditioners in the order of the priority order. a transmission means;
Control target value calculation means for calculating a control target value that defines an upper limit value when the output power of the plurality of power conditioners is totaled;
Based on the control target value calculated by the control target value calculation means, the control is performed on each of the power conditioners such that the upper limit value of the output power of the power conditioners becomes lower in the order of the higher priority. An output control device comprising a control command value calculation means for calculating a command value. The output control device according to claim 1, wherein the control command value calculation means uses a control command value such that an upper limit value of the output power of the power conditioner is 0 according to the priority order. Furthermore, a suppression power calculation means is provided for calculating, as suppression power, a sum of upper limit values when output power of the plurality of power conditioners is suppressed based on the control target value,
The control command value calculation means calculates a control command value such that the upper limit value of the output power is 0 while the sum of the PCS ratings of the power conditioner using the control command value such that the upper limit value of the output power is 0 is equal to or less than the suppressed power. The output control device according to claim 2, wherein the output control device is used. The control command value calculation means calculates a control command value of a power conditioner other than a power conditioner using a control command value whose upper limit value of output power is 0 so that the upper limit value is larger than 0. The output control device according to claim 3, characterized in that: 5. The output control device according to claim 4, wherein the control command value calculation means uses a control command value that enables the remaining power conditioners to generate power up to the PCS rating. The control target value calculation means includes:
Calculating the ratio between the power consumption and the total PCS rating, which is the sum of the PCS ratings of the plurality of power conditioners,
determining the setting difference value corresponding to the calculated ratio by referring to a table showing setting difference values stored corresponding to the ratio;
The output control device according to claim 1, wherein the control target value is determined based on a value obtained by dividing the PCS total rating by a value obtained by subtracting the set difference value from the power consumption. . A total of upper limit values of output power of the plurality of power conditioners specified by the control command value corresponds to a total of upper limit values of output power of the plurality of power conditioners specified by the control target value. The output control device according to claim 1, characterized in that: The output control device according to claim 1, wherein the priority order is changed daily. An output control device for controlling output power of a plurality of power conditioners connected to a solar cell,
power consumption measuring means that determines the power consumption as the sum of the received power and the output power of the plurality of power conditioners;
A control command value that prioritizes the plurality of power conditioners, and transmits a control command value for defining an upper limit value of the output power to the power conditioners in the order of the priority order. a transmission means;
an output control device comprising: control command value calculation means for calculating the control command value to each of the power conditioners so that the upper limit value of the output power of the power conditioners becomes lower in order of the priority order; . An output control device for controlling output power of a plurality of power conditioners connected to a solar cell,
power consumption measuring means that determines the power consumption as the sum of the received power and the output power of the plurality of power conditioners;
A control command value that prioritizes the plurality of power conditioners, and transmits a control command value for defining an upper limit value of the output power to the power conditioners in the order of the priority order. a transmission means;
Suppression power calculation means for calculating suppression power that defines a total value when output power of the plurality of power conditioners is suppressed;
Based on the suppressed power calculated by the suppressed power calculation means, the control command value to each of the power conditioners is determined such that the upper limit value of the output power of the power conditioner becomes lower in the order of the highest priority. An output control device comprising a control command value calculation means for calculating the. An output control device for controlling the output power of multiple power conditioners connected to solar cells,
power consumption measuring means that determines the power consumption as the sum of the received power and the output power of the plurality of power conditioners;
A control command value that prioritizes the plurality of power conditioners, and transmits a control command value for defining an upper limit value of the output power to the power conditioners in the order of the priority order. transmission means,
control target value calculation means for calculating a control target value that defines an upper limit value when the output power of the plurality of power conditioners is totaled; and
Based on the control target value calculated by the control target value calculating means, the control is performed on each of the power conditioners such that the upper limit value of the output power of the power conditioner becomes lower in the order of the priority. An output control program for functioning as a control command value calculation means for calculating command values. An output control device for controlling the output power of multiple power conditioners connected to solar cells,
power consumption measuring means that determines the power consumption as the sum of the received power and the output power of the plurality of power conditioners;
A control command value that prioritizes the plurality of power conditioners, and transmits a control command value for defining an upper limit value of the output power to the power conditioners in the order of the priority order. a transmission means, and
Output control for functioning as a control command value calculation means for calculating the control command value to each of the power conditioners so that the upper limit value of the output power of the power conditioners becomes lower in the order of the highest priority. program. An output control device for controlling the output power of multiple power conditioners connected to solar cells,
power consumption measuring means that determines the power consumption as the sum of the received power and the output power of the plurality of power conditioners;
A control command value that prioritizes the plurality of power conditioners, and transmits a control command value for defining an upper limit value of the output power to the power conditioners in the order of the priority order. transmission means,
Suppression power calculation means for calculating suppression power that defines a total value when output power of the plurality of power conditioners is suppressed, and
Based on the suppressed power calculated by the suppressed power calculation means, the control command value to each of the power conditioners is determined such that the upper limit value of the output power of the power conditioner becomes lower in the order of the highest priority. An output control program for functioning as a control command value calculation means for calculating. A solar power generation system comprising a plurality of solar cells, a plurality of power conditioners connected to the plurality of solar cells, and an output control device for controlling output power of the plurality of power conditioners,
The output control device includes:
power consumption measuring means that determines the power consumption as the sum of the received power and the output power of the plurality of power conditioners;
A control command value that prioritizes the plurality of power conditioners, and transmits a control command value for defining an upper limit value of the output power to the power conditioners in the order of the priority order. a transmission means;
Control target value calculation means for calculating a control target value that defines an upper limit value when the output power of the plurality of power conditioners is totaled;
Based on the control target value calculated by the control target value calculating means, the control is performed on each of the power conditioners such that the upper limit value of the output power of the power conditioner becomes lower in the order of the priority. A solar power generation system comprising: a control command value calculation means for calculating a command value. A solar power generation system comprising a plurality of solar cells, a plurality of power conditioners connected to the plurality of solar cells, and an output control device for controlling output power of the plurality of power conditioners,
The output control device includes:
power consumption measuring means that determines the power consumption as the sum of the received power and the output power of the plurality of power conditioners;
A control command value that prioritizes the plurality of power conditioners, and transmits a control command value for defining an upper limit value of the output power to the power conditioners in the order of the priority order. a transmission means;
and a control command value calculation means for calculating the control command value to each of the power conditioners so that the upper limit value of the output power of the power conditioners becomes lower in the order of the priority. system. A solar power generation system comprising a plurality of solar cells, a plurality of power conditioners connected to the plurality of solar cells, and an output control device for controlling output power of the plurality of power conditioners,
The output control device includes:
power consumption measuring means that determines the power consumption as the sum of the received power and the output power of the plurality of power conditioners;
A control command value that prioritizes the plurality of power conditioners, and transmits a control command value for defining an upper limit value of the output power to the power conditioners in the order of the priority order. a transmission means;
Suppression power calculation means for calculating suppression power that defines a total value when output power of the plurality of power conditioners is suppressed;
Based on the suppressed power calculated by the suppressed power calculation means, the control command value to each of the power conditioners is determined such that the upper limit value of the output power of the power conditioner becomes lower in the order of the highest priority. A solar power generation system comprising: a control command value calculation means for calculating.