Power generation system, power generation control method, and power generation control program

Abstract

To suppress instability in the power supply caused by power fluctuations in the power generation system. [Solution] The power generation system 1, which includes a fuel cell device 5 and a photovoltaic power generation device 3, is equipped with a control unit EMS 11 that activates the fuel cell device 5 when it detects at least one of the following: the power generated by the photovoltaic power generation device 3 falls below the target power generation power, and the fluctuation range of the power demand of the power generation system 1, including fluctuations in the power generated by the photovoltaic power generation device 3, exceeds a predetermined range.

Description

Technical Field

[0001] The present invention relates to a power generation system including a fuel cell device and a solar power generation device, a power generation control method, and a power generation control program.

Background Art

[0002] There is known a technique having a solar power generation device and a fuel cell device, and supplying the generated power of the fuel cell device to the load side when the supply-demand difference between the generated power of the solar power generation device and the power consumption on the load side is negative, and stopping the power generation of the fuel cell device when the supply-demand difference is positive (Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In recent years, technological developments have been made to contribute to the efficiency of sustainable and advanced energy. The conventional technology performs control based on the positive or negative of the supply-demand difference, and has a problem that, for example, it does not respond to fluctuations in the generated power of the solar power generation device caused by changes in solar radiation intensity.

Means for Solving the Problems

[0005] A power generation system according to an aspect of the present invention is a power generation system including a fuel cell device and a solar power generation device, and includes a control unit that activates the fuel cell device when at least one of the following is detected: the generated power of the solar power generation device becomes less than or equal to the target generated power; and the fluctuation range of the power demand of the power generation system including the fluctuation of the generated power of the solar power generation device exceeds a predetermined range. Another aspect of the present invention is a power generation control method for a power generation system including a fuel cell device and a photovoltaic power generation device, comprising: a first step of detecting that the power generated by the photovoltaic power generation device falls below a target power generation power; a second step of detecting that the fluctuation range of the power demand of the power generation system, including fluctuations in the power generated by the photovoltaic power generation device, exceeds a predetermined range; and a third step of starting the fuel cell device when detection is made in at least one of the first and second steps. Another aspect of the present invention is a power generation control program, which controls the power generation of a power generation system consisting of a fuel cell device and a photovoltaic power generation device, and causes a computer to execute: a first process that detects when the power generated by the photovoltaic power generation device falls below a target power generation power; a second process that detects when the range of fluctuations in the power demand of the power generation system, including fluctuations in the power generated by the photovoltaic power generation device, exceeds a predetermined range; and a third process that starts the fuel cell device when a detection is made in at least one of the first and second processes. [Effects of the Invention]

[0006] According to the present invention, it is possible to suppress instability in the power supply caused by power fluctuations in the power generation system. [Brief explanation of the drawing]

[0007] [Figure 1] A schematic diagram showing an example of a power generation system. [Figure 2A] A schematic diagram illustrating the temporal changes in power output (PV power generation). [Figure 2B] A schematic diagram illustrating the fluctuating components. [Figure 3] A flowchart illustrating an example of the processes performed by EMS. [Figure 4] A schematic diagram showing an example of a power generation system in modified example 1. [Modes for carrying out the invention]

[0008] <Overview> In recent years, there has been an increase in the number of cases where power generation systems, including those utilizing renewable energy sources such as solar and wind power, are installed in facilities of consumers (such as factories and buildings) that receive AC power from power companies and other electricity providers. Such power generation systems are connected to (or linked to) the power grid located under the control of a substation, and the electricity generated by the power generation equipment within the power generation system is output to the loads within the power generation system (power-consuming devices such as factories within the facility). In addition, any surplus electricity that is not consumed by the loads within the power generation system is output to the power grid. Generally, the flow of electricity from the consumer side to the power grid is called "reverse power flow," and the electricity output from the consumer side to the power grid is called "reverse power flow." The power grid is the name given to the system that supplies electricity generated by power companies and other electricity providers to consumers who receive it.

[0009] Here, power suppliers such as electric power companies are obligated to ensure a stable power supply. In other words, they are required to maintain a constant frequency and voltage across the entire power system, including reverse power flow. Therefore, suppliers control the frequency of the entire power system by using multiple control methods according to the magnitude of the fluctuation period of the increasing and decreasing load on the power system.

[0010] Specifically, for load components with fluctuation periods of 20 minutes or longer, Economic Dispatching Control (EDC) is implemented to enable the most economical distribution of generated power. EDC is a control method based on a daily load fluctuation forecast, and it is considered difficult to respond to the moment-to-moment increases and decreases in load (components with fluctuation periods smaller than 20 minutes).

[0011] Therefore, suppliers perform multiple control measures to adjust the amount of power supplied to the power grid in response to the constantly fluctuating load and to stabilize the frequency. These controls, excluding EDC, are called frequency control, and they adjust for load fluctuations that cannot be handled by EDC. To explain in more detail, components with fluctuation periods of approximately 10 seconds or less can be naturally absorbed by the self-regulating nature of the power system itself. Furthermore, components with fluctuation periods of approximately 10 seconds to several minutes can be handled by governor-free operation of the generators at each power plant supplying power to the power system. In addition, components with fluctuation periods of several minutes to approximately 20 minutes can be handled by Load Frequency Control (LFC). In Load Frequency Control, the amount of power supplied is controlled by adjusting the power output of LFC power plants based on control signals from the supplier's central dispatch center.

[0012] However, the power generated by power generation devices that utilize renewable energy such as solar power can fluctuate rapidly in response to changes in solar radiation intensity, for example. Rapid fluctuations in power generation can have a significant negative impact on the frequency stability of the interconnected power grid. This negative impact becomes more pronounced as the number of consumers with power generation systems that include renewable energy devices increases. In the future, if the number of consumers with such power generation systems increases further, it will be necessary to maintain the stability of the power grid connected to these power generation systems by configuring each power generation system to absorb rapid fluctuations in power generation within its own system.

[0013] Therefore, in this embodiment, a power generation system is provided that absorbs fluctuations in generated power so as to suppress rapid fluctuations in the generated power of a power generation device utilizing renewable energy to within the LFC adjustment range of the power grid connected to the power generation system. Specifically, the power generation system comprises a power generation device utilizing renewable energy and a fuel cell device equipped with a function to absorb fluctuations in the generated power of this power generation device. Details of this power generation system will be explained in detail with reference to the diagrams.

[0014] <Power generation system> FIG. 1 is a schematic configuration diagram showing an example of a power generation system 1 according to an embodiment of the invention. As shown in FIG. 1, the power generation system 1 includes a photovoltaic power generation (hereinafter referred to as PV) device 3, a power conditioner (Power Conditioning System: hereinafter referred to as PCS) 3A, a fuel cell device 5, a PCS 5A, a storage battery 7, a PCS 7A, a hydrogen production device 9, a hydrogen tank 10, an energy management device (Energy Management System: hereinafter referred to as EMS) 11, and a power meter 13.

[0015] The power generation system 1 is interconnected with a power grid 100. In the embodiment, the loads of a plurality of consumers who use the power supplied by the power grid 100 are collectively referred to as a load 200. Also, in FIG. 1, a configuration including the storage battery 7 and the corresponding PCS 7A, and the hydrogen production device 9 and the hydrogen tank 10 is illustrated, but these configurations may be omitted. That is, the power generation system 1 may include at least the PV device 3 and the corresponding PCS 3A, the fuel cell device 5 and the corresponding PCS 5A, etc.

[0016] <PV device> The PV device 3 is a power generation device that utilizes sunlight as an example of renewable energy. The PCS 3A controls the power generation operation of the PV device 3 and converts the generated power (PV power) by the PV device 3 into alternating current of a predetermined voltage and a predetermined frequency. Note that the PCS 3A according to the embodiment has a maximum power point tracking (MPPT) control function. The MPPT control function refers to a function that automatically adjusts the operating voltage of the PV device 3 so that the generated power by the PV device 3 becomes maximum.

[0017] <Fuel cell device> The fuel cell device 5 generates electricity by reacting hydrogen contained in the fuel gas with oxygen as an oxidant contained in the air. In the embodiment, a polymer electrolyte fuel cell (PEFC) which is superior in startup characteristics to a solid oxide fuel cell (SOFC) is used. The fuel cell device 5 includes a resistor 51 as a resistance member for consuming surplus power. The resistor 51 may be called a waste resistance. Note that the fuel cell device 5 may be referred to as the FC device 5. A signal indicating the operating state of the FC device 5 is configured to be readable by the EMS11. The PCS5A controls the power generation operation of the FC device 5 and converts the generated power by the FC device 5 into alternating current with a predetermined voltage and a predetermined frequency.

[0018] <Battery> The battery 7 stores (charges) the generated power (FC power) obtained by the power generation operation of the FC device 5 in a secondary battery and discharges from the secondary battery when performing power assist described later. The battery 7 includes, for example, a lithium ion battery or the like. In the battery 7, a current value, a voltage value, and a temperature of the secondary battery are detected by a sensor group not shown, and the SOC (State Of Charge, which may also be called the battery charge rate) of the secondary battery is calculated by a controller not shown. A signal indicating the calculated SOC is configured to be readable by the EMS11. The PCS7A converts the discharge power of the battery 7 into alternating current with a predetermined voltage and a predetermined frequency.

[0019] <Hydrogen production device> The hydrogen production device 9 produces hydrogen gas using the PV power generated by the PV device 3. Specifically, hydrogen gas is produced by electrolyzing water into hydrogen and oxygen using the PV power.

[0020] The hydrogen tank 10 is an example of a hydrogen storage device that stores the hydrogen gas produced by the hydrogen production device 9. The above FC device 5 uses the hydrogen gas stored in the hydrogen tank 10 as a fuel gas.

[0021] <ems> The EMS11 is composed of a computer including a CPU and ROM and RAM as memory. The CPU controls the operation of the power generation system 1 by executing programs recorded in the ROM, etc. As an example, as will be described later, the FC device 5 is used to absorb fluctuations in the power generated by the PV device 3. The program to be executed by EMS11 may be pre-recorded in the ROM of EMS11, or it may be transferred to the RAM of EMS11 via a communication line from an external device (not shown). EMS11 determines the power generated by PV device 3 (including fluctuations) based on the signal from PCS3A. EMS11 also determines the power generated by FC device 5 based on the signal from PCS5A, and outputs control signals (start-up control, power generation control, stop-down control, and power depletion control) to FC device 5. Furthermore, the EMS11 determines the discharge amount of the battery 7 based on the signal from the PCS7A and outputs a control signal (charge / discharge control) to the battery 7. In addition, the EMS11 determines the operating status of the hydrogen production device 9 (including the power consumption of the hydrogen production device 9) based on the signal from the hydrogen production device 9 and outputs control signals (start control, operation control, stop control) to the hydrogen production device 9. The EMS11 determines the amount of hydrogen gas stored based on the signal from the hydrogen tank 10 and outputs a control signal (hydrogen gas delivery control) to the hydrogen tank 10.

[0022] <Power meter> The power meter 13 detects reverse power flow from the power generation system 1 to the power grid 100. The signal indicating the detected power is configured to be readable by the EMS 11. In addition, if the power generation system 1 receives power from the power grid 100, the power meter 13 may also detect forward power flow.

[0023] The above-described power generation system 1 supplies the power required to operate the hydrogen production device 9 with the power from the PV device 3, the FC device 5, and the storage battery 7. Further, the power generation system 1 can also supply the power from at least one of the PV device 3, the FC device 5, and the storage battery 7 to the load 200 side (reverse power flow).

[0024] <FC Control> The EMS 11 executes control for the FC device 5 (hereinafter referred to as FC control). As an example, the EMS 11 performs FC control based on the generated power of the PV device 3 (PV generated power). The EMS 11 performs FC first control as FC control and FC second control as FC control.

[0025] <FC Second Control> The FC second control is control for the FC device 5 performed based on the fluctuation of the PV generated power. First, regarding the change in the PV generated power, it will be described with reference to FIG. 2A. FIG. 2A is a schematic diagram illustrating the temporal change of the generated output (PV generated power). The horizontal axis indicates time, and the vertical axis indicates the level of the generated output. According to FIG. 2A, as the solar radiation intensity increases, the generated output increases, and at time t1, the generated output exceeds the target generated power Tgt Pwr of the PV device 3. The target generated power Tgt Pwr may be, for example, 70% of the rated output of the PV device 3. Between time t2 and time t3, the generated output repeatedly fluctuates by increasing and decreasing as the passing clouds block the sunlight or move away from the sun (in the state of not blocking the light). After time t3, the power generation by the PV device 3 continues without the clouds blocking the sunlight. As the altitude of the sun decreases and the solar radiation intensity weakens, the generated output decreases, and at time t4, the generated output falls below the target generated power Tgt Pwr.

[0026] In the embodiment, among the fluctuations of the generated output between time t2 and time t3, the fluctuations within approximately 20 minutes are targeted, and the fluctuations of the generated output are absorbed using the FC device 5. To this end, the EMS11 calculates the total power (demand power in the power generation system 1) by adding the fluctuations in the power output of the PV device 3 and the fluctuations in the power consumption within the power generation system 1 (corresponding to the power consumption of the hydrogen production device 9 in this embodiment), and then performs a moving average operation on the total power. In moving average processing, the total power at a given time is calculated as the average value of the total power at multiple time points sampled over a predetermined period prior to that time (approximately 10 minutes in this embodiment). Furthermore, EMS11 calculates (or extracts) the fluctuating components of total power within approximately 20 minutes by subtracting the total power before moving average processing from the average value of the total power. The extracted fluctuating components correspond to the fluctuating components of demand power in power generation system 1. Furthermore, if the hydrogen production device 9 is omitted in power generation system 1, or if the hydrogen production device 9 is stopped, the above total power essentially represents the fluctuation in power output from the PV device 3.

[0027] Figure 2B is an example of a graph showing the extracted fluctuation components, and is a schematic diagram explaining the fluctuation components of the total power mentioned above. Points of interest PoF-1 and PoF-2 in Figure 2A correspond to points of interest PoF-1 and PoF-2 in Figure 2B, respectively.

[0028] In Figure 2B, the adjustment range 21R shown by lines 21U and 21L corresponds to the LFC adjustment range that can be adjusted by load frequency control (LFC) performed in the power system 100. The LFC adjustment range is based on the LFC capacity, which is the adjustment capacity secured by the power company or other power supplier for each supply area of ​​the power system 100. In this embodiment, the EMS 11 determines the adjustment range 21R of the power demand of the power generation system 1 in accordance with the LFC adjustment range of the power system 100. In the embodiment, a power consumption resistor activation threshold is defined as a power demand level lower than a predetermined level with respect to the power demand level indicated by line 21U, which is shown by line 23U. When the fluctuation component of the power demand in the power generation system 1 exceeds line 23U, the EMS 11 causes the excess portion (the surplus power indicated by the slanted lines) to be consumed by the resistor 51 of the FC device 5. That is, in the FC second control, a control signal is output to the FC device 5 so as to consume the surplus power indicated by the slanted lines using the FC device 5.

[0029] Conversely, a FC activation threshold is defined as a power demand level higher than a predetermined level with respect to the power demand level indicated by line 21L, which is shown by line 23L. When the fluctuation component of the power demand in the power generation system 1 falls below line 23L, the EMS 11 covers the shortfall portion (the power shortage indicated by the slanted lines) with the FC generated power by the FC device 5. That is, in the FC second control, a control signal is output to the FC device 5 so as to fill the shortfall in the power generation amount of the PV device 3 indicated by the slanted lines using the FC device 5.

[0030] As described above, in the embodiment, the range 23R indicated by lines 23U and 23L corresponds to the allowable range of fluctuations in the power demand in the power generation system 1. That is, when the fluctuation component of the power demand in the power generation system 1 deviates from the above allowable range 23R (in other words, when the fluctuation width of the total power exceeds the allowable range 23R), the EMS 11 causes the FC device 5 to absorb the surplus or deficit power, thereby preventing an adverse effect on the power system 100 side (the adjustment by the load frequency control (LFC) performed in the power system 100 becomes insufficient, and the stable supply of power in the power system 100 is not ensured) due to the fluctuation of the generated power by the PV device 3 (the fluctuation within approximately 20 minutes described above).

[0031] <FC First Control> The FC first control is control of the FC device 5 performed based on a comparison between the generated output of the PV device 3 and the target generated power Tgt Pwr. EMS11, when the power output falls below the target power generation power Tgt Pwr (before time t1 and after time t4 in Figure 2A), will use FC power generated by FC device 5 to cover at least the difference. In other words, in FC second control, a control signal is output to FC device 5 to resolve the power shortage of PV device 3 using FC device 5.

[0032] <Explanation of the flowchart> An example of the processing performed by EMS11 will be explained with reference to the flowchart in Figure 3. When power generation is performed by the PV device 3 and the power output (PV power generation) exceeds, for example, 10% of the rated output of the PV device 3, EMS11 starts the processing shown in Figure 3. In step S10 of Figure 3, the EMS 11 determines whether the PV power generated by the PV device 3 is less than or equal to a predetermined value. If the PV power generated is less than or equal to the target power generated Tgt Pwr, the EMS 11 affirms step S10 and proceeds to step S20. If the PV power generated exceeds the target power generated Tgt Pwr, the EMS 11 negates step S10 and proceeds to step S50.

[0033] In step S20, the EMS11 starts FC first control and proceeds to step S30.

[0034] In step S30, the EMS11 determines whether the PV power generated by the PV device 3 exceeds a predetermined value. If the PV power generated exceeds the target power generated Tgt Pwr, the EMS11 affirms step S30 and proceeds to step S40. If the PV power generated does not exceed the target power generated Tgt Pwr, the EMS11 negates step S30 and waits for the PV power generated to exceed the target power generated Tgt Pwr.

[0035] In step S40, the EMS11 terminates the FC first control and proceeds to step S50.

[0036] In step S50, the EMS11 determines whether the fluctuation range of the PV power generated by the PV device 3 exceeds a predetermined range. If the fluctuation range (the fluctuation range of the total power as described above) exceeds the allowable range 23R, the EMS11 affirms step S50 and proceeds to step S60. If the fluctuation range does not exceed the allowable range 23R, the EMS11 negates step S50 and proceeds to step S90.

[0037] In step S60, the EMS11 starts FC second control and proceeds to step S70.

[0038] In step S70, the EMS11 determines whether the fluctuation range of the PV power generated by the PV device 3 is within a predetermined range. If the fluctuation range is within the allowable range 23R, the EMS11 affirms step S70 and proceeds to step S80. If the fluctuation range is not within the allowable range 23R, the EMS11 negates step S70 and waits for the fluctuation range to fall within the allowable range 23R.

[0039] In step S80, the EMS11 terminates the FC second control and proceeds to step S90.

[0040] In step S90, EMS11 determines whether to terminate. EMS11 terminates the process shown in Figure 3 if the PV power generation falls to, for example, less than 10% of the rated output of PV device 3, or if the administrator performs a termination operation. If the PV power generation is 10% or more of the rated output of PV device 3, and the administrator does not perform a termination operation, EMS11 returns to step S10 and repeats the process described above.

[0041] According to the embodiments described above, the following effects and advantages are achieved. (1) The power generation system 1 according to the embodiment includes an FC device 5 and a PV device 3, and includes an EMS 11 as a control unit that activates the FC device 5 when it detects at least one of the following: the power generated by the PV device 3 is less than or equal to the target power generated Tgt Pwr, and the fluctuation range of the power demand of the power generation system 1, including the fluctuation of the power generated by the PV device 3 (in other words, the fluctuation component of the power demand), exceeds a predetermined allowable range 23R. With this configuration, for example, if the solar radiation intensity is low and the power generated by the PV device 3 is less than the target power generation power Tgt Pwr, the power shortage can be covered by the power generated by the FC device 5. Also, for example, if the fluctuation in the power generated by the PV device 3 due to changes in solar radiation intensity causes the fluctuating component of the power demand of the power generation system 1 to exceed a predetermined waste resistance starting threshold (line 23U) or fall below a predetermined FC starting threshold (line 23L), the fluctuating component exceeding the waste resistance starting threshold or the fluctuating component below the FC starting threshold can be absorbed (consumed or filled) by the FC device 5. As a result, even when the power generation system 1 is connected to the power grid 100, it is possible to contribute to the stable supply of power by the power grid 100 without adversely affecting the frequency stability of the connected power grid 100.

[0042] (2) The power generation system 1 described in (1) above further includes a hydrogen production device 9 as a load device that uses the power generated by the PV device 3, and the EMS 11 calculates the total power of the fluctuations in the power generated by the PV device 3 and the fluctuations in the power consumed by the hydrogen production device 9 as the demand power. With this configuration, it becomes possible to appropriately calculate the fluctuating component of the power demand of the power generation system 1, including the load device. This makes it possible to appropriately absorb the fluctuating component that exceeds the LFC capacity of the power grid 100 connected to the power generation system 1 into the FC device 5.

[0043] (3) In the power generation system 1 described in (2) above, if the fluctuation in demand power exceeds the allowable range 23R, the EMS 11 will discard the excess power using the resistor 51 which is a resistive member provided in the FC device 5. Since surplus power can be consumed within the power generation system 1, even when the power generation system 1 is connected to the power grid 100, it can contribute to the stable supply of power by the power grid 100 without adversely affecting the frequency stability of the connected power grid 100.

[0044] (4) In the power generation system 1 described in (2) or (3) above, if the fluctuation in demand power falls below the permissible range 23R, the EMS 11 causes the FC device 5 to generate the insufficient power. Since the power generation system 1 can generate any insufficient power, even when the power generation system 1 is connected to the power grid 100, it can contribute to the stable supply of power by the power grid 100 without negatively affecting the frequency stability of the power grid 100 to which it is connected.

[0045] (5) In the power generation system 1 described in (2) or (3) above, if the power generated by the PV device 3 falls below the target power generation Tgt Pwr, the EMS 11 causes the FC device 5 to generate the insufficient power. With this configuration, even when the power generation system 1 is connected to the power grid 100, it is possible to contribute to the stable supply of power by the power grid 100 without adversely affecting the frequency stability of the power grid 100 to which it is connected.

[0046] (6) In the power generation system 1 described in (1) above, the EMS 11 determines the allowable range 23R based on the LFC adjustment range which can be adjusted by the load frequency control on the power grid 100 side to which the power generation system 1 is connected. With this configuration, even when the power generation system 1 is connected to the power grid 100, it is possible to contribute to the stable supply of power by the power grid 100 without adversely affecting the frequency stability of the power grid 100 to which it is connected.

[0047] The above embodiment can be modified into various forms. Modifications will be described below. (Variation 1) Figure 4 is a schematic diagram showing the power generation system 1A according to modified example 1. The difference between Figure 4 and Figure 1 is that in Figure 4, a DC / DC converter 6 is provided instead of the PCS 5A in Figure 1. The DC / DC converter 6 in Modification 1 controls the power generation operation of the FC device 5 and converts the DC voltage output from the FC device 5 into a predetermined DC voltage. For example, it boosts the DC voltage output by the FC device 5 to a voltage equivalent to the DC voltage output from the PV device 3. Generally, a DC / DC converter 6, which has a DC voltage conversion function, can be made smaller and less expensive compared to a PCS5A, which has a DC to AC conversion function. Therefore, it is possible to reduce the cost of power generation system 1A compared to power generation system 1 in Figure 1. The PCS3A converts the voltage of the parallel-connected DC power supply (PV device 3, DC / DC converter 6) into AC at a predetermined voltage and frequency. The PCS3A in Figure 4 only needs to be capable of stably converting the rated output of the PV device 3 into AC at a predetermined voltage and frequency, so the PCS3A in Figure 1 can be used as is.

[0048] (Modification 2) In the FC second control described above, the EMS 11 explains an example in which, when the fluctuating component of the demand power in the power generation system 1 (or 1A) falls below line 23L, the difference (the power deficit shown by the diagonal lines in the lower right of Figure 2B) is covered by the FC power generated by the FC device 5. In the modified example 2, the system may be configured to compensate for the insufficient power generation of the PV device 3 by using power discharged from the battery 7 in addition to, or instead of, the power generated by the FC device 5.

[0049] (Variation 3) In the above explanation, a resistor 51 was given as an example of a resistive element for consuming surplus power, but a heating element such as a heater may be provided instead of, or together with, the resistor 51.

[0050] The above description is merely an example, and the present invention is not limited by the embodiments and modifications described above, as long as the features of the present invention are not impaired. It is also possible to arbitrarily combine one or more of the above embodiments and modifications, and to combine modifications with each other. [Explanation of Symbols]

[0051] 1.1A power generation system, 3 PV equipment, 3A, 5A, 7A PCS, 5 FC equipment, 6 DC / DC converter, 7 battery, 9 hydrogen production equipment, 10 hydrogen tank, 11 EMS, 13 power meter, 21R adjustment range, 23R tolerance range, 51 resistor, 100 power grid, 200 load, Tgt Pwr target power generation< / ems>

Claims

1. A power generation system including a fuel cell device and a photovoltaic power generation device, The system includes a control unit that activates the fuel cell device when it detects at least one of the following: the power generated by the solar power generation device falls below the target power generation device, or the fluctuation range of the power demand of the power generation system, including the fluctuation in the power generated by the solar power generation device, exceeds a predetermined range. A power generation system characterized by the following features.

2. In the power generation system according to claim 1, The system further includes a load device that uses the power generated by the aforementioned photovoltaic power generation device, The control unit calculates the total power of the fluctuations in the power generated by the solar power generation device and the fluctuations in the power consumption of the load device as the demand power. A power generation system characterized by the following features.

3. In the power generation system according to claim 2, If the fluctuation in the power demand exceeds the predetermined range, the control unit will use a resistive member provided in the fuel cell device to dissipate the excess power. A power generation system characterized by the following features.

4. In the power generation system according to claim 2 or 3, The control unit, when the fluctuation in the power demand falls below the predetermined range, causes the fuel cell device to generate the insufficient power. A power generation system characterized by the following features.

5. In the power generation system according to claim 2 or 3, The control unit, if the power generated by the solar power generation device falls below the target power generation device, causes the fuel cell device to generate the necessary power. A power generation system characterized by the following features.

6. In the power generation system according to claim 1, The control unit determines the predetermined range based on an adjustment range that can be adjusted by the load frequency control on the power grid side to which the power generation system is connected. A power generation system characterized by the following features.

7. A method for controlling the power generation of a power generation system including a fuel cell device and a photovoltaic power generation device, The first step is to detect when the power generated by the solar power generation device falls below the target power generation power, A second step of detecting that the range of fluctuations in the power demand of the power generation system, including fluctuations in the power generated by the solar power generation device, exceeds a predetermined range, The system includes a third step of starting the fuel cell device when the detection is performed in at least one of the first and second steps, A power generation control method characterized by the following:

8. A program for controlling power generation in a power generation system consisting of a fuel cell device and a solar power generation device, A first process for detecting when the power generated by the aforementioned solar power generation device falls below the target power generation power, A second process for detecting when the fluctuation range of the power demand of the power generation system, including the fluctuation of the power generated by the solar power generation device, exceeds a predetermined range, When the detection is made in at least one of the first and second processes, the computer is instructed to execute a third process that starts the fuel cell device. A power generation control program characterized by the following features.

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