JP6030365B2 - Power supply system - Google Patents

Description

  The present invention relates to a power supply system that appropriately controls the supply of power from a system different from a commercial power system.

  In recent years, as a system for supplying power to a power system (referred to as a load system) to which a load is connected, a power supply system including an auxiliary power system that supplies power to the load system in a system different from a commercial power system Introduction is increasing. In the power supply system including the auxiliary power system, a part of the demand power of the load system is supplied with power from the auxiliary power system, and the supply of power from the commercial power system is reduced. As such an auxiliary power system, a solar battery, a wind power generator, and the like that are equipped with a power generation device using a regenerative energy with a small environmental load are increasing.

  In the power supply system, an upper limit (hereinafter referred to as set power) of received power from the commercial power system (average value thereof) is set in advance, and when the demand power of the load system exceeds the set power, Power is supplied from the auxiliary power system. As a result, so-called peak cut is performed in which the received power from the commercial power system is suppressed so as not to be larger than the set power (see, for example, Japanese Patent Laid-Open No. 2008-306832).

  Currently, in Japan, the power supplier charges the power usage fee (the amount of received power received from the commercial power grid) by adding the basic fee (contract fee) determined in advance and the metered fee according to the power usage. Has been decided. The basic charge is determined based on the maximum peak (hereinafter referred to as peak power) of the received power over the past year. In other words, even if it is a short period in the past year, if there is a prominent power usage record (maximum peak power), it becomes a basic charge based on the maximum peak power for one year and is set high. Since the peak cut is possible by using the power supply system, the maximum peak power can be lowered and the basic charge can be kept low.

  In the solar cell, the amount of power generation is likely to fluctuate depending on conditions such as sunlight and temperature. Similarly, in a power generation device that uses renewable energy other than solar cells, such as a wind power generator, the amount of power generation is influenced by the state of the environment, and variations tend to occur. If the power generation amount varies in this way, the power supplied from the auxiliary power system may vary, and the peak cut effect may be reduced. Moreover, if the fluctuation | variation of the electric power (demand electric power) consumed with a load system | strain is large, the electric power required for a peak cut cannot be supplied only with the said electric power generating apparatus, and the effect of a peak cut may reduce.

  Therefore, in order to correct the variation in the amount of power generated by the power generation device and make the power supplied from the auxiliary power system constant or substantially constant, the power supply provided with a power storage device (storage battery) such as a battery in the auxiliary power system A system has been proposed.

  By providing the storage battery in the auxiliary power system, when the power generation amount of the power generator is small, the power supplied from the auxiliary power system to the load system is made constant or substantially constant by adding the power of the storage battery can do. Thereby, the power supply system can perform reliable peak cut.

  The storage battery stores electric power from the commercial power system during a period (mainly at night) when the power demand of the load system is low. In addition, when the power generation amount of the solar battery exceeds the power supplied from the auxiliary power system to the load system, the storage battery can be charged with the power generated by the solar battery. That is, the storage battery is in a so-called floating charge state in which the battery is discharged when the amount of power generated by the solar battery is small and charged when the amount of power generated is large.

  And in the said commercial power grid, compared with the daytime when electric power demand is large, the electric power charge is often set cheaply at night when electric power demand is low. By adopting the power supply system as described above, the storage battery is charged with nighttime power that is less expensive than daytime, and used as part of daytime demand power of the load system. Can be reduced.

  Furthermore, the peak cut as described above suppresses the sum of demand power from exceeding the amount of power supplied (the sum of power supplied to all power consumers by the power supplier), resulting in the occurrence of large-scale power outages. It is also possible to suppress the expansion of facilities in preparation for a major power outage.

JP 2008-306832 A

  In the power supply system having the above-described configuration, when the variation in the power generation amount of the solar cell is large or the variation in the demand power of the load system is large, the variation in the power value supplied from the storage battery becomes large. In addition, since the storage battery is in a floating charge state, discharging and charging are frequently repeated due to fluctuations in the amount of power generated by the solar battery or demand power of the load system.

  That is, in the power supply system, since the power (current) for charging / discharging the storage battery varies greatly and frequently, the storage performance of the storage battery tends to deteriorate. When the storage performance of the storage battery is reduced, the power that can be supplied from the storage battery is reduced, so that the power generation amount of the power generation device cannot be sufficiently supplemented, and the peak cut effect is reduced.

  Therefore, an object of the present invention is to provide a power supply system that can stably reduce (peak cut) the maximum value of received power from a commercial power system over a long period of time.

  In order to achieve the above object, the present invention provides a power generation device, a power storage device, and an output stabilization device, and supplies auxiliary power for assisting received power from a commercial power system to a load system to which a load is connected. When the demand power of the load system becomes larger than a predetermined set power in a predetermined reference period, the auxiliary power is supplied from the power generation device and the power storage device to the load system. And a control unit that controls the output stabilizing device so as to perform a peak cut operation. The control unit collects power supply by discharging the power storage device in a preset period within the reference period. The power supply system is characterized in that the output stabilizing device is controlled so as to perform.

  According to this configuration, since the power supply by discharging the power storage device is performed in a preset period, frequent and large current fluctuations during discharging of the power storage device can be suppressed. In addition, since the power storage device is discharged in a preset period, the period during which the power storage device is discharged can be shortened.

From the above, charge and discharge is prevented from being frequently performed of the electric storage device, it is possible to suppress deterioration of the power storage capacity of the power storage device. Accordingly, the power supply system can perform the peak cut operation for a long period of time without replacing the power storage device. Examples of the output stabilization device include an inverter that converts the generated power of the power generation device and the discharge power of the power storage device into alternating current and converts the received power into direct current.

  The said structure WHEREIN: The said control part may control the said output stabilization apparatus so that the electric power generated by the said electric power generating apparatus may become the said auxiliary power, and may control not to discharge the said electrical storage apparatus.

  According to this configuration, the auxiliary power may be larger than the power required by the load system (difference between demand power and set power). In this case, the received power from the commercial power system within the reference period (Average value) can be reduced. Thereby, the effect of the peak cut operation can be enhanced. In addition, since all the power generated by the power generation device is used as auxiliary power, it is difficult for the power storage device to be charged with the power generated by the power generation device, and the power storage device is prevented from being repeatedly charged and discharged. it can. As a result, the power supply system can suppress deterioration of the power storage capacity of the power storage device, and can perform a peak cut operation over a long period of time.

  In the above configuration, the control unit compares the integrated value of the difference between the demand power and the set power with the integrated value of the auxiliary power during the peak cut operation, and the integrated value of the auxiliary power is the demand value. The output stabilizing device may be controlled to start discharging the power storage device when the difference between the electric power and the set power becomes smaller than an integrated value.

  While the auxiliary power can be provided by the power generated by the power generation device, the power storage device is not discharged, so that deterioration due to the discharge of the power storage device can be suppressed. As a result, the power supply system can suppress deterioration of the power storage capacity of the power storage device, and can perform a peak cut operation over a long period of time.

  In the above configuration, when the difference between the demand power and the set power is larger than the generated power of the power generation device until the reference period ends after the supply of power by discharging the power storage device is completed, The control unit may control the output stabilizing device so that a difference between the demand power and the set power is the auxiliary power.

  In the above configuration, the output stabilization device may have a configuration capable of independently adjusting the generated power from the power generation device and the discharge power of the power storage device.

  According to this configuration, it is possible to reliably stop the discharge of the power storage device, so that deterioration of the power storage device can be suppressed. In addition, the apparatus which adjusts the electric power generated from the said electric power generating apparatus and the apparatus which adjusts the discharge electric power of the said electrical storage apparatus can mention what uses a DC / DC converter.

  In the above configuration, the output stabilization device has a configuration in which the generated power from the power generation device and the discharge power from the power storage device are input independently, and by adjusting the generated power You may have the structure which can restrict | limit the discharge of the said electrical storage apparatus.

  In the above configuration, the power generation device and the power storage device may be directly connected, and the connection point may be connected to the output stabilization device.

  In the above configuration, a solar cell can be given as the power generation device. Moreover, it is not limited to a solar cell, but a physical or chemical device using a natural energy such as a wind power generator or a geothermal power generator, a power generator using a gas turbine and / or a steam turbine, or a fuel cell. And the like, which generate electricity by using typical energy.

  ADVANTAGE OF THE INVENTION According to this invention, the electric power supply system which can suppress degradation of an electrical storage apparatus and can perform the reduction | decrease (peak cut) of the maximum value of the received electric power from a commercial power grid stably over a long period of time can be provided.

It is a block diagram of an example of the power supply system concerning the present invention. FIG. 2 is a block diagram illustrating an auxiliary power system of the power supply system illustrated in FIG. 1. It is a figure which shows a reference | standard period. It is a figure which shows supply power, demand power, and auxiliary power when performing the peak cut operation. It is a flowchart which shows the peak cut operation | movement of the electric power supply system concerning this invention. It is a block diagram which shows the auxiliary | assistant electric power system used for the other example of the electric power supply system concerning this invention. It is a block diagram which shows the auxiliary | assistant electric power system used for the further another example of the electric power supply system concerning this invention. It is a block diagram which shows the auxiliary | assistant electric power system used for the further another example of the electric power supply system concerning this invention. It is a block diagram which shows the auxiliary | assistant electric power system used for the further another example of the electric power supply system concerning this invention.

(First embodiment)
Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a block diagram of an example of a power supply system according to the present invention. In the following explanation, when there is a description of demand power, received power, auxiliary power, etc., the average value of each power over a certain period is used unless otherwise specified. .

  As shown in FIG. 1, the power supply system A supplies power from the commercial power system CS and / or the auxiliary power system BS (auxiliary power source 1) to the load system LS to which the loads Ld1 to Ld3 are connected. System. As shown in FIG. 1, the power supply system A includes an auxiliary power source 1, a power conditioner 2 (output stabilization device), a power distribution unit 3, a power detection unit 4, a control unit 5, and a storage unit 6. It has. The auxiliary power source 1 includes a solar battery 11 that is a power generation device that uses renewable energy, and a storage battery 12 that is a power storage device. In the power supply system A, a system including the auxiliary power source 1 and the power conditioner 2 is used as the auxiliary power system BS.

  The solar cell 11 is a power generation device that converts sunlight into electrical energy, and since it is well known in the art, its details are omitted. The solar cell 11 outputs direct current electricity. The storage battery 12 is a secondary storage battery that can be repeatedly discharged and charged. Examples of the storage battery 12 include a lithium secondary battery, a nickel hydrogen battery, a nickel cadmium battery, and a lead storage battery. The output of the storage battery 12 is direct current.

  Since the commercial power system CS and the load system LS are alternating current and the auxiliary power source 1 is direct current, the power from the auxiliary power source 1 cannot be directly supplied to the load system LS. Therefore, in the auxiliary power system BS, the output of the auxiliary power source 1 is converted by the power conditioner 2 into alternating current synchronized with alternating current flowing through the commercial power system CS. The power conditioner 2 is a conversion device that can also convert alternating current into direct current. For example, when the storage battery 12 is charged, the alternating current supplied from the commercial power system CS is converted into direct current. The power conditioner 2 is controlled by the control unit 5.

  The power conditioner 2 will be described in more detail. FIG. 2 is a block diagram showing an auxiliary power system of the power supply system shown in FIG. As shown in FIG. 2, a first DC / DC converter 21 to which the solar battery 11 is connected, a second DC / DC converter 22 to which the storage battery 12 is connected, a first DC / DC converter 21, and a second DC / DC converter 22 are provided. A connected DC / AC converter (inverter) 23 is provided.

  The first DC / DC converter 21 is a conversion device that converts the output of the solar cell 11 into electric power suitable for the input of the inverter 23. The first DC / DC converter 21 is configured to detect the maximum power point of the solar cell 11. That is, the power conditioner 2 can control the solar cell 11 so that the power generated by the solar cell 11 is maximized. Further, the first DC / DC converter 21 has a configuration that can prevent electricity from flowing into the solar cell 11 (backflow).

  Similarly to the first DC / DC converter 21, the second DC / DC converter 22 also converts the output of the storage battery 12 into electric power suitable for the input of the inverter 23. The second DC / DC converter 22 also has a function of converting the power supplied from the inverter 23 into power suitable for charging the storage battery 12.

  The inverter 23 is a conversion device that converts the direct current output from the first DC / DC converter 21 and / or the second DC / DC converter 22 into alternating current synchronized with the alternating current supplied from the commercial power system CS. Further, the inverter 23 can also convert alternating current supplied from the commercial power system CS into direct current. In other words, the second DC / DC converter 22 and the inverter 23 have a configuration capable of bidirectionally converting electric power. Further, the output of the power conditioner 2 fluctuates depending on the operation of the inverter 23, and the inverter 23 is configured to require an input corresponding to the output. That is, when the inverter 23 outputs at the maximum output, the electric power input to the inverter 23 is determined. When the generated power of the solar battery 11 is smaller than the input power required by the inverter 23, the discharge power of the storage battery 12 is input to the inverter 23. Detailed operation will be described later.

  The power conditioner 2 is a device that determines the auxiliary power supplied from the auxiliary power source 1 including the solar battery 11 and the storage battery 12 by having the above-described configuration. The power conditioner 2 is controlled by the control unit 5 and preferentially uses the output from the solar battery 11 and supplements the insufficient power with the power stored in the storage battery 12. The storage battery 12 is charged with the received power from the commercial power system CS when the demand power decreases (mainly at night). By charging the storage battery 12 with the received power from the commercial power system CS, by suppressing fluctuations in the power (current) flowing through the rechargeable battery 12 during charging, it is possible to suppress deterioration due to variations in power when charging the storage battery 12. Can do. Moreover, compared with the case where it charges with the surplus electric power supplied as auxiliary electric power among the generated electric power of the solar cell 11, charging time becomes short, and it is possible to suppress degradation of the storage battery 12 also from this.

  The power distribution unit 3 is arranged at a branch portion between the commercial power system CS, the auxiliary power system BS, and the load system LS. The power distribution unit 3 connects the commercial power system CS and the auxiliary power system BS, and flows power from the commercial power system CS to the load system LS, or flows from the commercial power system CS and the auxiliary power system BS to the load system LS. Is a device for mixing. The power distribution unit 3 also performs an operation of flowing power from the commercial power system CS to the auxiliary power system BS when the storage battery 12 is charged. That is, the power distribution unit 3 is a device for distributing power from the commercial power system CS and / or the auxiliary power system BS to each system.

  Calculation of received power from the commercial power system CS is performed based on a predetermined period (hereinafter referred to as a reference period). Here, it is assumed that the length of the reference period is 30 minutes, and there is a reference period separation at 00 minutes and 30 minutes of each time.

  The power detection unit 4 detects the received power from the commercial power system CS. That is, the power detection unit 4 detects the received power from the commercial power system CS at a predetermined timing (for example, every 10 seconds), and transmits the detected power value to the control unit 5 as power information IP.

  Based on the power information IP from the power detection unit 4, the control unit 5 controls the auxiliary power system BS and the power distribution so that the received power from the commercial power system CS in the reference period is equal to or less than the target power (set power). The unit 3 is controlled.

  The control unit 5 controls the operations of the power conditioner 2 and the power distribution unit 3 so as to supply power (hereinafter referred to as auxiliary power) from the auxiliary power system BS to the load system LS (peak cut operation). Thereby, the received power from the commercial power system CS in the reference period becomes equal to or less than a certain value, in other words, the maximum peak value of the received power in the reference period is reduced (cut). Moreover, when charging the storage battery 12 as described above, the power distribution unit 3 is controlled so that the power from the commercial power system CS goes to the auxiliary power system BS, and the power conditioner 2 is controlled so as to convert alternating current into direct current. To do.

  The control unit 5 includes a control circuit including an arithmetic device such as a microcomputer. The control unit 5 is connected to the storage unit 6 and extracts information inside the storage unit 6 and stores information in the storage unit 6 as necessary.

  The storage unit 6 stores data necessary for controlling the power supply system A. The storage unit 6 includes a ROM dedicated to calling, a RAM that can be called and written, and a nonvolatile memory that does not volatilize without supplying power, such as a flash memory. The storage unit 6 stores data such as set power and preliminary stock power, for example. In the following description, it is assumed that these data are included. However, depending on the control method, different data may be required, and the necessary data in that case will be described at that time.

  As described above, in the power supply system A, the received power from the commercial power system CS in the reference period is reduced by supplying the auxiliary power from the auxiliary power system BS to the load system LS.

  Next, a reference period serving as a reference for calculating received power from the commercial power system CS will be described with reference to the drawings. FIG. 3 is a diagram showing a reference period. As shown in FIG. 3, the reference period ST is continuous at regular intervals (here, 30 minutes).

And the power demand of the load system LS is constantly changing, and is changing frequently even during the reference period ST. Therefore, in order to cope with this change in demand power, the control unit 5 divides the reference period ST into a plurality of divided periods T _m (n: n is a natural number) (m is a natural number of 1 to n), and the divided period T _m. The power demand of each load system LS is calculated. The control unit 5, and calculates the electric power demand of the load system LS divided period T _m based on the power information IP supplied from the power detection unit 4.

As described above, the power detection unit 4 detects the received power from the commercial power system CS and transmits it to the control unit 5 as power information IP. Then, the control unit 5 based on the power information IP, is calculating demand power of load system LS of each divided period T _m. For example, a power detection unit 4 is sending the detected power information IP received power at finer timing than division period T _m. In this case, the control unit 5 integrates the power value based on the power information IP calculates the average value of the received power in the divided period T _m, further, adding the average value of the auxiliary power from the auxiliary power system BS Thus, the power demand of the load system LS is calculated. Incidentally, other than this, may be provided with a method for calculating the power demand in the divided period T _m. Therefore, the power detection unit 4 detects received power at least once every divided period.

  Note that the divided period is obtained by dividing the reference period ST in order to calculate auxiliary power based on the demand power of the load system LS. The greater the number of divisions, the higher the control accuracy. However, if the division period is too small, the processing capacity of the power distribution unit 3 and the control unit 5 and the capacity of the auxiliary power system BS (mainly the operation speed of the power conditioner 2 and the control unit 5) may be exceeded. Therefore, the accuracy of control decreases. That is, the division number n is determined in consideration of the capabilities of the power distribution unit 3, the control unit 5, and the auxiliary power system BS so that the capability can be controlled with a certain level of accuracy.

  In addition, it is difficult for power plants (not shown) provided in the commercial power system CS to finely vary the power generation amount, and in order to prevent the power supply from being interrupted, the power generation amount is determined based on the maximum power demand. Yes. And in the time zone when electric power demand is low, there is much electric power that is generated but not used. Therefore, based on the time information IT, the control unit 5 distinguishes between a time zone in which the power demand is high (daytime time zone) and a time zone in which the power demand is low (night time zone). It also contributes to reducing the burden on the commercial power system by charging the storage battery 12 in a time zone where the power demand is low and discharging it in a time zone where the power demand is high. It contributes to.

  In addition, the power supplier adjusts the power transmission amount (power generation amount) in the next reference period based on the power supply amount in the reference period, that is, the sum of the received power from the commercial power system CS by a plurality of power consumers. doing. In addition, in a plurality of power consumers, the time periods when the peak of demand power occurs often overlap. By adopting the power supply system A among a plurality of power consumers, it is possible to reliably reduce the sum of demand power, that is, the sum of power received from the commercial power grid CS by all power consumers. Thereby, an increase in the amount of power generation can be suppressed, energy saving can be achieved, and an increase in size of the power supply facility (such as a transmission line or a substation facility) can be suppressed.

  Furthermore, in a normal commercial power system CS, the amount of power used is charged as the sum of a basic fee and a metered fee that is metered according to the received power. In most cases, the metered charge during the daytime when the power demand is high is higher than during the night when the power demand is low. As described above, performing the peak cut operation is the same as replacing high daytime power with cheap nighttime power, and also has the effect of reducing the usage fee for power consumers. Furthermore, the basic charge is determined by the maximum value of the received power in a certain period. This received power is calculated as the received power in the reference period, and the power supply system A can suppress the maximum value of the received power by supplying the auxiliary power from the auxiliary power system BS to the load system LS. It is also possible to suppress the increase in basic charges.

  The peak cut operation of the power supply system A will be described. In the power supply system A, when the received power from the commercial power system CS becomes larger than the preset set power, the amount exceeding the set power is supplied from the auxiliary power system BS as auxiliary power. The auxiliary power source 1 of the auxiliary power system BS includes a solar battery 11 and a storage battery 12, and usually power is preferentially supplied from the solar battery 11.

  That is, the output of the power conditioner 2 is usually covered by the generated power of the solar battery 11 and supplemented by the discharge of the storage battery 12 as necessary. When the power generation amount of the solar battery 11 frequently fluctuates, or when the demand power of the load system LS fluctuates frequently, the discharge power (current) of the storage battery 12 fluctuates frequently and greatly, and the deterioration of the storage battery 12 is severe. Become. Therefore, in the power supply system A of the present invention, in the divided period where the peak cut operation is necessary, the storage battery 12 is output at a certain output or more in a part of the divided period, and the output from the storage battery 12 is output in the remaining part. The peak cut operation (control) is performed so as to stop as much as possible.

  The peak cut operation of the power supply system A according to the present invention will be described below with reference to the drawings. FIG. 4 is a diagram illustrating supply power, demand power, and auxiliary power when the peak cut operation is performed.

Figure 4 is a k-th (k> 2) division of the period T _k ~ division period T demand power of load system LS of the _{k + 6 P1 k ~P1 k +} 6 reference period ST, the power receiving that receives power from the commercial power system CS Electric power P2 _{k to} P2 _{k + 6} and auxiliary power P3 _{k to} P3 _{k + 6} supplied from the auxiliary power system BS are shown by bar graphs. In each divided period, the target power received from the commercial power system CS is set in advance as the set power PA.

In the power supply system A according to the present invention, in order to suppress the fluctuation of the discharge power of the storage battery 12 from being large and frequent, the auxiliary power system BS provides auxiliary power during the divided periods T _{k + 1} to T _{k + 5} . The maximum output P3A of the power conditioner 2 is output as electric power. Usually, the maximum output of the power conditioner 2 is set to be larger than the generated power of the solar battery 11, and the discharge power of the storage battery 12 is large when the power conditioner 2 is at the maximum output.

In the divided period T _{k + 6} , the auxiliary power system BS stops the maximum output from the power conditioner 2, and uses the difference between the demand power P1 _{k + 6} and the set power PA as the auxiliary power P3 _{k + 6.} Output to. The maximum in the auxiliary power system BS, in the reference period ST, the division period T _{k + 1} ~ divided period T _{k + 5} regardless demand power P1 k _{+ 1} ~P1 k _{+ 5,} the auxiliary power of the power conditioner 2 The output is P3A.

By operating the power conditioner 2 in this way, the integrated value of the peak cut power until the divided period T _{k + 5} is larger than the requested value, that is, the state in which the peak cut power is stocked. It has become. In the subsequent peak cut operation, even if the generated power of the solar cell 11 is supplied as auxiliary power, it is equivalent to performing the peak cut until the stock runs out. From this, the number of discharges of the storage battery 12 can be reduced, and deterioration of the storage battery can be suppressed.

  Next, the peak cut operation of the power supply system A according to the present invention will be described with reference to the drawings. FIG. 5 is a flowchart showing the peak cut operation of the power supply system according to the present invention.

In the power supply system A, when the storage battery 12 is discharged in all the reference periods ST in which the peak cut operation is performed, the discharge power of the storage battery 12 is frequently switched, and the life of the storage battery 12 is shortened. Further, the storage battery 12 may use up the stored power. Therefore, in the power supply system A of the present invention, at the beginning of the reference period ST in which the peak cut operation is performed, the generated power PV _k of the solar cell 11 is used as auxiliary power regardless of the magnitude of the set power PA and the demand power P1 _k. Supply. Then, generation power PV _k peak cut power stocks supplied as auxiliary power of the solar cell 11 is eliminated and (becomes 0), supplies a certain period auxiliary power maximum output P3A power conditioner 2 as auxiliary power. At this time, cover the amount of missing power generated PV _m solar cells 11 in the discharge power of the battery 12.

Thereafter, the auxiliary power P3 _k is covered only by the generated power PV _k of the solar cell 11. When the peak cut power stock is depleted, supplying a material obtained by adding the discharge power of the battery 12 to the power generation PV _k of the solar cell 11 as auxiliary power P3 _k.

In order to perform the operation as described above, the control unit 5 performs the peak cut operation according to the procedure shown in FIG. The peak cutting operation shown in FIG. 5 detects the power demand of the divided periods T ₁ through T ₃₀ in which the reference period ST (30 min) divided by 1 minute intervals.

First, when the reference period ST starts, the control unit 5 prepares a variable k for identifying each divided period, and sets the variable to 1 (step S11). The variable k indicates the order from the beginning of the current divided period, and is added by one each time the divided period T _k is switched.

The control unit 5 detects the demand power P1 _k of the load system LS in the divided period T _k (step S12). The control unit 5 acquires the generated power PV _k of the solar cell 11 from the power conditioner 2 (step S13). Since the generated electric power of the solar cell 11 is constantly changing due to fluctuations in conditions such as sunshine and temperature, the control unit 5 detects the generated electric power of the solar cell 11 finely and integrates the solar power of the divided period T _k . The generated power PV _k of the battery 11 may be used.

Control unit 5 determines whether there are any remaining peak cut power stock in current divided period T _k. The controller 5 subtracts the generated power PV _m of the solar cell 11 and the preset set power PA from the demand power P1 _m from the divided period T _{1 at} the beginning of the reference period ST to the current divided period T _k . It is determined whether the integrated value (stock of peak cut power) is greater than 0 (step S14). Thereby, it is determined whether or not to discharge from the storage battery 12 as described above. In addition, you may determine to discharge from the storage battery 12 by methods other than this.

When the stock of peak cut power remains (in the case of NO in step S14), the control unit 5 outputs the generated power PV _k of the solar cell 11 as the auxiliary power P3 _{k so} as to output the power conditioner 2 (first DC thereof). / DC converter 21) is controlled (step S15). Then, 1 is added to the variable k along with the end of the divided period T _k (step S16). Since the reference period ST is divided into 30 divided periods T _{1 to} T ₃₀ , the variable k does not exceed 30. Therefore, the control part 5 confirms whether the variable k does not exceed 30 (step S17). When the variable k exceeds 30 (Yes in step S17), the control unit 5 ends the peak cut operation in the reference period ST.

If the variable k does not exceed 30, the process returns to step S12. Further, when the stock of peak cut power is lost, the auxiliary power P3 _k cannot be covered only by the generated power PV _k of the solar cell 11. When the stock of the peak cut power is lost or becomes smaller than 0 (Yes in step S14), the control unit 5 uses the maximum power (maximum output) P3A that can be output by the power conditioner 2 as auxiliary power for 5 minutes. Output (step S18). In addition, the time for outputting the maximum power is not limited to 5 minutes.

Even when outputs the maximum output P3A power conditioner 2 as auxiliary power, the solar cell 11 is outputting generated power PV _k. The control unit 5 controls the second DC / DC converter 22 to discharge from the storage battery 12 the power _obtained by subtracting the generated power PVk from the maximum output P3A. After 5 minutes, 5 is added to the variable k (step S19).

Then, after outputting the auxiliary power 5 minutes maximum output P3A power conditioner 2, the control unit 5 detects a power demand P1 _k of the current divisional period T _k (step S110). The control unit 5 and at the same time detects the generated power PV _k of the solar cell (step S111).

The control unit 5 determines whether or not the stock of peak cut power remains due to the supply of auxiliary power with the maximum output of the power conditioner 2 (step S112). Note that, in step S112, the integrated value of the output of 5 minutes at maximum output P3A power conditioner 2 performed in step S18 is, by subtracting the generated power PV _m and the set power PA of the solar cell 11 from the power demand P1 _m value When the accumulated value from the divided period T _{1 at} the beginning of the reference period ST to the current divided period T _k is larger, it is determined that there is a peak cut power stock, and when it is smaller, it is determined that there is no peak cut power stock. To do. The determination may be made by other methods.

When there is a stock of peak cut power (YES in step S112), the control unit 5 performs the peak cut operation by a method of outputting the maximum output P3A of the power conditioner 2 (the same method as before). That is, the control unit 5 controls the power conditioner 2 so that the auxiliary power P3 _k becomes the generated power PV _k of the solar cell 11 (step S113).

Further, after the maximum output P3A of the power conditioner 2 is output for 5 minutes, when the stock of peak cut power disappears (in the case of NO in step S112), the control unit 5 uses the demand power P1 _k of the load system LS to It is determined whether or not the assist of the discharge power from the storage battery 12 is necessary based on whether the value obtained by subtracting the generated power _PVk and the set power PA of the battery 11 is greater than 0 (step S114). When the value obtained by subtracting the generated power PV _k and the set power PA of the solar cell 11 from the demand power P1 _k of the load system LS is smaller than 0 (NO in step S114), the control unit 5 generates the power of the solar cell 11. determines that it is possible to cover the auxiliary power P3 _k in power PV _k, auxiliary power P3 _k controls the power conditioner 2 as a power generation PV _k of the solar cell 11 (step S113).

On the other hand, when the value obtained by subtracting the generated power PV _k and the set power PA of the solar battery 11 from the demand power P1 _k of the load system LS is larger than 0 (YES in step S114), the control unit 5 The auxiliary power P3 _k is the difference between the demand power P1 _k and the set power PA, that is, the power generated by assisting the generated power PV _k of the solar cell 11 with the discharged power of the storage battery 12. Thus, the power conditioner 2 is controlled (step S115).

In step S113 or step S115, the auxiliary power P3 _k is output, and when the divided period T _k ends, the control unit 5 adds 1 to the variable k (step S116). Then, the control unit 5 determines whether or not the divided period T _k is the last divided period T _30, that is, whether or not the reference period ST is ended (step S117).

When the divided period T _k is the divided period T ₃₀ (YES in step S117), the control unit 5 ends the peak cut operation in the reference period ST. When the divided period T _k has not reached the divided period T ₃₀ (NO in step S117), the process returns to step S110, and the control unit 5 repeats the peak cut operation.

  As described above, in the power supply system A having the configuration in which the auxiliary power source 1 includes the solar battery 11 in which the generated power is likely to fluctuate and the storage battery 12 with limited storage power, the deterioration of the storage battery 12 is suppressed. However, the received power from the commercial power system CS can be reduced.

  In addition, in step S18, although the time which outputs auxiliary | assistant electric power in the case of discharging the storage battery 12 is 5 minutes, it is not limited to this. A time other than 5 minutes may be used. For example, the maximum output of the power conditioner 2 may be used as the auxiliary power until the integrated value of the discharge power of the storage battery 12 reaches a predetermined power value.

  Moreover, it is not limited to the maximum output of the power conditioner 2, The discharge electric power from the storage battery 12 may be made constant, and the electric power generated by the solar battery 11 may be added to the discharge electric power from the storage battery 12. In this case, when the sum of the generated power of the solar battery 11 and the discharged power from the storage battery 12 exceeds the maximum output of the power conditioner 2, the power conditioner 2 may adjust the generated power of the solar battery 11. The discharge power from the storage battery 12 may be adjusted. When the generated power of the solar battery 11 is adjusted, the discharge power from the storage battery 12 becomes constant, so that deterioration of the storage battery 12 can be suppressed. When the output power of the storage battery 12 is adjusted, the consumption of electrical energy stored in the storage battery 12 can be suppressed.

  Thus, by using the power supply system according to the present invention, the received power in the reference period can be accurately suppressed (the peak can be accurately cut). As a result, it is possible to reduce the pay-as-you-go charge of the power charge of the power consumer, and it is possible to suppress an increase in the basic charge by suppressing the power peak. Moreover, since the amount of power received in the reference period can be reduced, the power supplier can suppress an increase in the amount of power generation. Furthermore, it is possible to suppress the occurrence of a power failure due to an increase in peak power, and it is possible to suppress the facility expansion for suppressing the power failure.

  As described above, in the peak cut operation, the division period is not limited to 1 minute, and may be shorter or longer. If the length is shortened, the number of divisions increases, so that the accuracy of control increases. Further, if the length is increased, the number of divisions is reduced, so that the accuracy is lowered, but the control unit 5 is not required to have high processing capability. For example, if the sunshine conditions, demand power conditions, etc. are not likely to fluctuate over a long period (several days to several weeks), the divided period is lengthened. If these conditions fluctuate in a short period (several hours), the divided period is What can be shortened can be mentioned.

  By performing the peak cut operation as described above, the number of discharges of the storage battery 12 can be reduced, and deterioration of the storage battery 12 can be suppressed accordingly. Moreover, since the shortage of the generated power of the solar battery 11 can be compensated by the storage battery 12, it is possible to perform a reliable peak cut operation, and the power charge can be suppressed accordingly. Further, since the peak power is cut, waste of supplied power can be reduced, energy consumption can be reduced, and enlargement of power generation equipment, power transmission equipment, and the like can be suppressed.

  In addition, this peak cut operation can be performed in the following embodiments.

(Second Embodiment)
Another example of the power supply system according to the present invention will be described with reference to the drawings. FIG. 6 is a block diagram showing an auxiliary power system used in another example of the power supply system according to the present invention. The configuration other than the auxiliary power system is the same as that of the power supply system shown in the first embodiment, and illustration and description thereof are omitted. As shown in FIG. 6, the auxiliary power system BS2 includes an auxiliary power source 1 and a power conditioner 2b.

  As shown in FIG. 6, the power conditioner 2 b includes a first DC / DC converter 21 and an inverter 23. The solar cell 11 is connected to the first DC / DC converter 21. The inverter 23 is connected to the first DC / DC converter 21 and the power distribution unit 3. Furthermore, the storage battery 12 is connected between the first DC / DC converter 21 and the inverter 23. That is, the power conditioner 2b has a configuration in which the second DC / DC converter 22 is omitted from the power conditioner 2.

  The power conditioner 2 b receives the control signal from the control unit 5 and operates the first DC / DC converter 21 and the inverter 23. In the power conditioner 2b, by operating the first DC / DC converter 21 and the inverter 23, only the generated power of the solar battery 11 is used as auxiliary power, or both the generated power of the solar battery 11 and the output power of the storage battery 12 are used. Has decided to use.

  Hereinafter, switching between the generated power of the solar battery 11 and the output power of the storage battery 12 by the power conditioner 2b will be described. The first DC / DC converter 21 can arbitrarily change the output voltage within a predetermined range. By making the output voltage higher than the voltage (terminal voltage) of the storage battery 12, discharge of the storage battery 12 (power conditioner) Supply of current to 2b) can be stopped. Conversely, by making the output voltage of the first DC / DC converter 21 lower than the voltage (terminal voltage) of the storage battery 12, the storage battery 12 can be discharged (power is drawn from the storage battery 12 to the power conditioner 2b).

  That is, when the auxiliary power is supplied only by the generated power of the solar battery 11, the first DC / DC converter 21 generates the power at the maximum power point and the output voltage is higher than the voltage of the storage battery 12. Adjust to. Thereby, it is suppressed that the storage battery 12 discharges.

  Further, when the auxiliary power is generated power of the solar battery 11 and discharge power of the storage battery 12, the storage battery 12 is discharged by making the output voltage of the first DC / DC converter 21 lower than the voltage of the storage battery 12. Thereby, auxiliary power can be output with the same power as the maximum output of the power conditioner 2b.

  In addition, the first DC / DC converter 21 is configured to prevent current from flowing to the solar cell 11, and when charging the storage battery 12, power from the inverter 23 is not supplied to the solar cell 11. Yes.

  Even in the power supply system including the power conditioner 2b, the peak cut operation as shown in FIG. 5 can be performed, and the same effects as those of the first embodiment can be obtained. Moreover, since the 2nd DC / DC converter 22 connected with the storage battery 12 is omitted as a structure of the power conditioner 2b, it is possible to reduce cost compared with the thing using the power conditioner 2.

(Third embodiment)
Still another example of the power supply system according to the present invention will be described with reference to the drawings. FIG. 7 is a block diagram showing an auxiliary power system used in still another example of the power supply system according to the present invention. The configuration other than the auxiliary power system is the same as that of the power supply system shown in the first embodiment, and illustration and description thereof are omitted. As shown in FIG. 7, the auxiliary power system BS3 includes an auxiliary power source 1 and a power conditioner 2c.

  As shown in FIG. 7, the power conditioner 2 c includes a DC / DC converter 24 and an inverter 23. The solar cell 11 and the storage battery 12 are electrically connected outside the power conditioner 2 c, and the connection wiring is connected to the DC / DC converter 24. Further, the inverter 23 is connected to the DC / DC converter 24 and the power distribution unit 3. That is, the power conditioner 2c omits the second DC / DC converter 22 from the power conditioner 2, and the solar battery 11 and the storage battery 12 are in a floating charge state.

  A backflow prevention unit 13 that prevents current from flowing through the solar cell 11 is attached to the wiring connected to the solar cell 11. The backflow prevention unit 13 prevents a current from flowing into the solar cell 11 when the storage battery 12 is charged with the received power from the commercial power system CS. Therefore, the structure provided with the diode may be sufficient, and a switch may be attached to the electric wire which goes to the solar cell 11, and it may operate so that a switch may be turned off at the time of charge of the storage battery 12. FIG. Here, a configuration including a diode is employed.

  The power conditioner 2 c receives the control signal from the control unit 5 and operates the DC / DC converter 24 and the inverter 23. In the power conditioner 2c, by operating the DC / DC converter 24 and the inverter 23, only the generated power of the solar battery 11 is used as auxiliary power, or both the generated power of the solar battery 11 and the output power of the storage battery 12 are used. Decide whether to use.

  Hereinafter, switching between the generated power of the solar battery 11 and the output power of the storage battery 12 by the power conditioner 2c will be described. The DC / DC converter 24 detects the maximum power point of the solar cell 11 and is configured to be able to adjust the output voltage of the solar cell 11. That is, the output voltage (current) of the generated power of the solar cell 11 is determined by the DC / DC converter 24.

  Then, by controlling the DC / DC converter 24 and setting the voltage of the generated power of the solar battery 11 higher than the voltage of the storage battery 12, discharge of the storage battery 12 (that is, power supply to the power conditioner 2c) is prevented. be able to. Moreover, the storage battery 12 can be discharged (electric power is supplied from the storage battery 12 to the power conditioner 2c) by setting the voltage of the generated power of the solar battery 11 lower than the voltage of the storage battery 12.

  As described above, by operating the DC / DC converter 24, even the power supply system including the power conditioner 2c can perform the peak cut operation as shown in FIG. 5, which is the first embodiment. The same effect can be obtained. Further, the configuration of the power conditioner 2c can be reduced in cost as compared with a configuration in which two DC / DC converters are provided.

  In addition, in auxiliary power system BS3 shown in FIG. 7, although it is in a floating charge state, the time (division period) discharged from the storage battery 12 can be restrict | limited by performing control similar to FIG. Thereby, it is possible to suppress frequent and large fluctuations in the electric power (current) discharged from the storage battery 12. Further, in the peak cut operation as shown in FIG. 5, all the generated power of the solar cell 11 is used as auxiliary power until there is no stock of peak cut power. Therefore, the storage battery 12 is not charged during this period. Moreover, after discharging from the storage battery 12, even after the stock of the peak cut power disappears, all the generated power of the solar battery 11 is used as auxiliary power, so charging from the solar battery 11 to the storage battery 12 is suppressed.

  From the above, in the auxiliary power system BS3 shown in FIG. 7, the auxiliary power source 1 is substantially in the floating charge state after the discharge of the storage battery 12 for 5 minutes is completed and the peak cut power stock Is shorter than the conventional power supply system. Therefore, the fluctuation | variation of the electric current by discharge / charging of the storage battery 12 can be suppressed, and deterioration of the storage battery 12 can be suppressed.

(Fourth embodiment)
Still another example of the power supply system according to the present invention will be described with reference to the drawings. FIG. 8 is a block diagram showing an auxiliary power system used in still another example of the power supply system according to the present invention. The configuration other than the auxiliary power system is the same as that of the power supply system shown in the first embodiment, and illustration and description thereof are omitted. As shown in FIG. 8, the auxiliary power system BS4 includes an auxiliary power source 1 and a power conditioner 2d.

  As shown in FIG. 8, the power conditioner 2 d has a configuration including an inverter 23. Details of the same configuration are omitted. The solar battery 11 and the storage battery 12 are electrically connected outside the power conditioner 2d, and the connection wiring is connected to the inverter 26. That is, the auxiliary power source 1 of the auxiliary power system BS4 is in a floating charge state. In the auxiliary power system BS4, the power conditioner 2d does not have a function of following the maximum power point of the solar battery 11, and the operation voltage, that is, the generated power is determined by the potential of the storage battery 12. That is, the generated power of the solar battery 11 is always generated at the same voltage as the discharged power of the storage battery 12.

  A backflow prevention unit 13 that prevents current from flowing through the solar cell 11 is attached to the wiring connected to the solar cell 11. The backflow prevention unit 13 prevents a current from flowing into the solar cell 11 when the storage battery 12 is charged with the received power from the commercial power system CS. Therefore, the structure provided with the diode may be sufficient, and a switch may be attached to the electric wire which goes to the solar cell 11, and it may operate so that a switch may be turned off at the time of charge of the storage battery 12. FIG.

  The power conditioner 2 d receives the control signal from the control unit 5 and operates the inverter 23. In the power conditioner 2d, by operating the inverter 26, it is determined whether only the generated power of the solar battery 11 is used as auxiliary power or both the generated power of the solar battery 11 and the output power of the storage battery 12 are used. ing.

  Hereinafter, switching between the generated power of the solar battery 11 and the output power of the storage battery 12 by the power conditioner 2d will be described. The inverter 23 has information on the maximum power of the solar cell 11. And the inverter 23 becomes a structure which can determine output electric power according to the electric power generated of the solar cell 11. FIG.

  Then, by causing the inverter 23 to operate so that the output power of the power conditioner 2d is the same as the generated power of the solar battery 11, discharge of the storage battery 12 (that is, power supply to the power conditioner 2d) can be prevented. . Moreover, the storage battery 12 can be discharged (electric power is supplied from the storage battery 12 to the power conditioner 2d) by operating the inverter 23 so as to have the maximum power that can be output by the power conditioner 2d.

  By operating the inverter 23 as described above, it is possible to perform the peak cut operation as shown in FIG. 5 even in the power supply system including the power conditioner 2d, and the same effects as those of the first embodiment can be obtained. Can be obtained. Further, the configuration of the power conditioner 2d can be reduced in cost as compared with a configuration using a DC / DC converter.

  In addition, in auxiliary power system BS4 shown in FIG. 8, although it is a floating charge state, the time (division period) discharged from the storage battery 12 can be restrict | limited by performing control similar to FIG. Thereby, it is possible to suppress frequent and large fluctuations in the electric power (current) discharged from the storage battery 12. Further, in the peak cut operation as shown in FIG. 5, all the generated power of the solar cell 11 is used as auxiliary power until there is no stock of peak cut power. Therefore, the storage battery 12 is not charged during this period. Moreover, after discharging from the storage battery 12, even after the stock of the peak cut power disappears, all the generated power of the solar battery 11 is used as auxiliary power, so charging from the solar battery 11 to the storage battery 12 is suppressed.

  From the above, in the auxiliary power system BS4 shown in FIG. 8, the auxiliary power source 1 is substantially in the floating charge state after the discharge of the storage battery 12 for 5 minutes is completed and the peak cut power stock Is shorter than the conventional power supply system. Therefore, the fluctuation | variation of the electric current by discharge / charging of the storage battery 12 can be suppressed, and deterioration of the storage battery 12 can be suppressed.

(Fifth embodiment)
Still another example of the power supply system according to the present invention will be described with reference to the drawings. FIG. 9 is a block diagram showing an auxiliary power system used in still another example of the power supply system according to the present invention. The configuration other than the auxiliary power system is the same as that of the power supply system shown in the first embodiment, and illustration and description thereof are omitted. As shown in FIG. 9, the auxiliary power system BS5 includes an auxiliary power source 1d and a power conditioner 2d.

  As shown in FIG. 8, the power conditioner 2d is configured to include an inverter 23, and includes a diode 141 and a switch 142 (switching element) on a circuit connected to the storage battery 12 of the auxiliary power source 1d. A current control circuit 14 is attached. As the switch 142, an electronic component such as a transistor, MOSFET, or IGBT may be employed, or a physical switch such as a relay may be employed. Further, the diode 141 can be omitted by using a switching element including a parasitic diode.

  The diode 141 of the current control circuit 14 is arranged so that the direction in which current flows in the storage battery 12 is the forward direction. The switch 142 is disposed in parallel with the diode 141. In the current control circuit 14, when the switch 142 is off and a forward bias voltage is applied to the diode 141, a current flows toward the storage battery 12 via the diode 141. Further, when the switch 142 is on, the current flows from the higher voltage to the lower voltage. Therefore, the switch 142 is arranged so that a current flows from the storage battery 12 to the power conditioner 2d when turned on.

  In the auxiliary power system BS5 having this configuration, when the switch 142 is off, the potential of the connection point between the solar battery 11 of the auxiliary power source 1d and the current control circuit 14 is that the diode 141 is connected. Equal to the voltage. Therefore, the operating voltage of the solar cell 11 is determined by the voltage of the storage battery 12, and power is generated at the operating voltage. At this time, no forward bias voltage is applied to the diode 141, and no current flows through the storage battery 12. Further, since the switch 142 is off, the discharge power of the storage battery 12 is not supplied. That is, the auxiliary power output from the power conditioner 2d has the maximum power generated by the solar cell 11.

  Further, when the switch 142 is turned on, the storage battery 12 and the power conditioner 2d are brought into conduction. At this time, the auxiliary power system BS5 is in the same floating charging state as the auxiliary power system BS4 shown in FIG. That is, by operating the inverter 23 so that the output power of the power conditioner 2d is the same as the generated power of the solar battery 11, discharge of the storage battery 12 (that is, power supply to the power conditioner 2d) can be prevented. . Moreover, the storage battery 12 can be discharged (electric power is supplied from the storage battery 12 to the power conditioner 2d) by operating the inverter 23 so as to have the maximum power that can be output by the power conditioner 2d. Moreover, it becomes possible to make all the generated electric power of the solar cell 11 into auxiliary electric power by making the output of the power conditioner 2d the maximum with the switch 142 turned off.

  According to this configuration, even when the operation of the power conditioner 2d becomes unstable, it is possible to forcibly cut off the supply of discharge power from the storage battery 12. Thereby, it can suppress that the storage battery 12 deteriorates by repeating charging / discharging, and it is possible for a power supply system to perform a peak cut operation stably over a long period of time.

  In each of the above-described embodiments, a solar cell is adopted as a power generation device of the power supply system. However, the present invention is not limited to this, and those that generate power independently, in particular, wind power and geothermal heat that use natural energy. Or a plurality of these including solar cells. Moreover, it is also possible to employ | adopt the power generator using a gas turbine, a steam turbine, or both, a fuel cell, etc. as a power generator.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to this content. The embodiments of the present invention can be variously modified without departing from the spirit of the invention.

  The present invention is applied to a power supply system for reducing received power received from a commercial power system, for example, a cogeneration system of an office building or a condominium, a solar power generation system of a general household, a power supply system of a factory, etc. Is possible.

A Power supply system 1 Storage battery 2 Power conditioner 3 Power distribution unit 4 Power detection unit 5 Control unit 6 Memory LS Load system BS Auxiliary power system CS Commercial power system

Claims (7)

A power supply system capable of supplying auxiliary power for assisting received power received from a commercial power system to a load power system having a load,
A power generator,
A power storage device;
An output stabilizing device for determining auxiliary power based on power generation of the power generation device and discharge of the power storage device;
A control unit that controls the power generation device, the power storage device, and the output stabilization device ;
The control unit divides a reference period serving as a reference for calculating received power received from the commercial power system into a plurality of divided periods, and in the divided period, the demand power of the load system is determined from a predetermined set power. When it is too large, it is possible to execute a peak cut operation to supply the auxiliary power to assist the received power to the load system,
The control unit includes an integrated value of a difference between the demand power and the set power and an integrated value of the auxiliary power from the beginning of the reference period to the present while the auxiliary power includes the generated power of the power generator. And in a plurality of consecutive divided periods immediately after the integrated value of the auxiliary power becomes smaller than the integrated value of the difference between the demand power and the set power, the discharge of the power storage device and the demand power A certain auxiliary power larger than the difference from the set power is supplied to the load system,
In a divided period after the plurality of consecutive divided periods, the generated power of the power generation device is used as the auxiliary power, and then an integrated value of the difference between the demand power and the set power is the plurality of consecutive divided periods. When the sum of the total amount of auxiliary power supplied to the power generator and the integrated value of the generated power of the power generation device becomes larger, the power storage device is discharged, and the difference between the demand power and the set power is calculated as the auxiliary power. The power supply system is characterized by controlling the output stabilizing device . The power supply system according to claim 1, wherein the control unit performs control using the maximum output of the output stabilizing device as the auxiliary power in the plurality of continuous divided periods . The power supply system according to claim 2, wherein the control unit discharges the power storage device with a predetermined output or more in the plurality of continuous divided periods . The output stabilizing device has a configuration in which the generated power from the power generation device and the discharge power from the power storage device are input independently, and by adjusting the generated power, The power supply system according to any one of claims 1 to 3 , wherein the power supply system has a configuration capable of limiting discharge . The output stabilization device has a configuration capable of independently adjusting the generated power from the power generation device and the discharge power of the power storage device. The power supply system according to Crab. The power supply system according to any one of claims 1 to 4, wherein the power generation device and the power storage device are directly connected, and a connection point thereof is connected to the output stabilization device . The power supply system according to any one of claims 1 to 6 , wherein the power generation device is a solar battery .

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