JP5485224B2 - Independent operation power supply system - Google Patents

Description

  The present invention provides an independently operated power system composed of a plurality of photovoltaic power generation systems, power storage devices, adjustment power supplies, loads, etc., for supplying power to the load while maintaining the frequency and voltage in the system. It relates to technology for efficient control and operation.

  Power generation facilities using natural energy (renewable energy) such as wind power and solar power as countermeasures against global environmental problems such as global warming and acid rain, depletion of fossil resources, and ensuring energy security Is being introduced.

  In particular, in an undeveloped power system area such as an isolated area or a depopulated area in a tropical area, power is currently supplied mainly by a diesel engine generator or the like. However, the fuel transportation cost is high due to geographical conditions, and the power supply system is expensive. Many of these areas have good sunshine conditions and are suitable for solar power generation. In addition to improving the economic efficiency through the effective use of renewable energy, the power supply system can contribute to the realization of a low-carbon society. The needs are high.

  These systems supply power individually to scattered power demands and are relatively small-scale systems. In addition, since not only the power system infrastructure but also the communication infrastructure is often undeveloped, new communication facilities will increase the cost of the entire system. Cost reduction is indispensable for the spread of these systems, and it is not a centralized control method that requires communication facilities, but autonomous control and operation using only local information without communication facilities. A system that can do this is required.

  Therefore, for example, in Patent Document 1, a plurality of power generation devices and power storage devices linked to an independently operated power system each have a frequency control function (AFC: Automatic Frequency Control), and according to its own information and system frequency. Thus, a technique for operating without central control by changing the target frequency of AFC is disclosed. In addition, a technique for preferentially operating a power generation device with high power generation efficiency at that time is disclosed.

JP 2005-328622 A

  The prior art disclosed in Patent Document 1 operates a device with high power generation efficiency preferentially, and in order to further improve economy, SOC (State Of Charge) management of a storage battery, power generation device It is necessary to operate based on a cost-optimized plan including factors that affect the non-linear partial load efficiency or maintenance costs. On the other hand, the centralized control method that operates while creating the optimum operation plan by monitoring the operation state of each device in real time has a problem that the communication equipment is costly.

  The present invention has been made to solve the above-described problem, and in an independently operated power supply system that uses renewable energy, each power generation device and power storage device perform operation using its own information. However, it aims to realize stable and economical operation.

In order to achieve the above object, the present invention is generally characterized by having the following configuration.
An independent operation type power supply system that includes a photovoltaic power generation device, a regulated power supply device, and a power storage device connected to a system bus, and that supplies power to a load connected to the system bus, the regulated power supply and Each of the control devices of the power storage device is created in advance for each of predetermined classification conditions uniquely determined by calendar information and own measurement information, and a reference operation pattern group for determining output sharing of each device Is selected from the reference operation pattern group for the current classification condition corresponding to the current date and time and the current own measurement information, and determined by the selected reference operation pattern. The output sharing after correction of the device to be controlled is calculated by correcting the output sharing using the current own-end measurement information, and the calculation It was based on the power sharing corrected was assumed and a control unit for controlling the operation of the control target apparatus.

  Further, the adjustment power supply device and the power storage device are provided with a means for measuring the amount of solar radiation and the outside air temperature, and the amount of solar radiation and the outside air temperature measured by the measuring means are used as the own measurement information. .

  According to the present invention, in an independently operated power supply system that uses renewable energy, each power generation device and power storage device can be operated using its own information, and can be operated stably and economically. can do.

1 is a schematic configuration example of an independently operated power supply system according to an embodiment of the present invention. 1 schematically shows a general operation concept of a photovoltaic power generation device, a regulated power supply device, and a power storage device that constitute an independently operated power supply system. It is a functional block diagram of the adjustment power supply control apparatus which concerns on this embodiment. It is a functional block diagram of the electrical storage apparatus control apparatus which concerns on this embodiment. It is a flowchart which shows the flow of the control processing in an adjustment power supply control apparatus. It is the figure which represented typically the definition of the solar radiation amount flag and the temperature flag. It is the figure which illustrated the classification table of the standard operation pattern held at a control device. It is a flowchart which shows the flow of the control processing in an electrical storage apparatus control apparatus. It is the flowchart which illustrated the procedure of the preparation process of a reference | standard driving | operation pattern group. It is a figure which shows an example of the optimal reference | standard driving | operation pattern produced.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic configuration example of an independently operated power supply system according to an embodiment of the present invention. In FIG. 1, the minimum components necessary for the description of the present invention are shown as components of the independently operated power supply system.

  As shown in FIG. 1, the independently operated power supply system 10 is an independently operated power supply system for supplying power to a specific area using renewable energy. The regulated power supply device 4 and the power storage device 5 are connected to the power line 1 that is a system bus through the power receiving facilities 33A, 43A, 53A, etc. for interconnection, respectively, and these devices are also connected to the power line 1 in the same manner. Electric power is supplied to the existing loads 2A, 2B and the like. Since the power generation output of the solar power generation device 3 greatly fluctuates depending on the solar radiation conditions, a diesel generator, a gas engine generator, a micro gas turbine generator, a fuel cell, etc. are used to compensate for the insufficient power in rainy weather etc. The adjustment power supply device 4 having a plurality of power generation devices (adjustment power sources) capable of controlling the power generation output of the solar power generation device 3 is installed, and surplus power in the daytime of the solar power generation device 3 is charged and discharged at night. In order to make effective use, a power storage device 5 having a power storage device such as a storage battery is installed. Here, the solar power generation device 3, the regulated power supply device 4, and the power storage device 5 do not have to be concentrated in a specific area. Incidentally, although the independently operated power supply system 10 is preferably applied to an area where the power system is not yet developed, the installation location is not particularly limited.

  The photovoltaic power generation device 3 is connected to a plurality of photovoltaic power generation panel groups 31A, 31B,... And DC power generated by the photovoltaic power generation panel groups 31A, 31B,. , Power converters 32A, 32B,... Having a protection function, power receiving facilities 33A, 33B,... Composed of transformers, switches, etc., and power converters 32A, 32A, And a self-end voltage / current detection device (not shown) used for control and protection performed by 32B and the like. The photovoltaic power generation panel groups 31A, 31B and the like do not need to be centrally installed in a specific area, and do not need to be connected to the power line 1 at one point. That is, they may be distributed and connected to the power line 1 at each installation location.

  The regulated power supply 4 includes a regulated power supply 41A, 41B, 41C,... That is a power generator capable of controlling the power generation output of a diesel generator, gas engine generator, micro gas turbine generator, fuel cell, or the like. The power receiving equipment 43A to 43C, etc., including the transformers and switches for connecting the regulated power supplies 41A to 41C to the power line 1, the regulated power supply control device 44 for controlling the regulated power supplies 41A to 41C, and the like, In addition to its own voltage / current detection device (not shown) used for the control performed by the regulated power supply control device 44, it is configured to include an operation state estimation measuring device 45 comprising means for measuring the amount of solar radiation and the outside air temperature. The The adjusted power supplies 41A to 41C and the like maintain the frequency and voltage within appropriate ranges based on the control command from the adjusted power supply control device 44 and the measurement information of the voltage / current detection device (not shown) at its own end. Therefore, control units 411A to 411C having a function of controlling active / reactive power are connected. The number of regulated power supplies 41A to 41C and the like is determined according to the demand power of the loads 2A and 2B and the like that are the targets of power supply.

  The power storage device 5 is a device that adjusts the power in the system by charging and discharging, and converts the direct current power generated by the storage batteries 51A, 51B,... In addition, interconnection power converters 52A, 52B,... Having interconnection protection functions for connection to the power line 1, and interconnection power receiving facilities 53A, 53B,. The self-end voltage / current detection device (not shown) used for control / protection performed by the interconnection power converters 52A, 52B, and the interconnection power converters 52A, 52B In addition to a power storage device control device 54 that transmits a control command such as operation / stop information, and a self-end voltage / current detection device (not shown) used for control performed by the power storage device control device 54, the amount of solar radiation and the outside air temperature Consisting of means to measure Rolling constructed and a state estimation measurement device 55. The interconnection power converters 52A, 52B, etc. each have an appropriate frequency and voltage range based on the control command from the power storage device control device 54 and the measurement information of the voltage / current detection device (not shown) at its own end. The active / reactive power is controlled to maintain the power. Secondary batteries such as lead storage batteries, lithium ion batteries, sodium / sulfur batteries, and redox flow batteries can be used as the storage batteries 51A and 51B. In addition, since these batteries need to be periodically refreshed, at least two sets are independently used in order to allow the independently operated power supply system 10 to stably supply power during this period. It is preferable that the configuration be operable.

  In the independently operated power supply system 10, the photovoltaic power generation device 3, the regulated power supply device 4, and the power storage device 5 are not connected by a communication line or the like, and do not exchange data such as an operation state with each other. Each is operated unattended (stand-alone). FIG. 2 schematically shows a general operation concept of the solar power generation device 3, the regulated power supply device 4, and the power storage device 5 that constitute the independent operation type power supply system 10. FIG. 2A shows the relationship between the outputs of the solar power generation device 3 and the power storage device 5, and FIG. 2B shows the output sharing with respect to the total demand.

  The solar power generation device 3 basically supplies generated power determined by the amount of solar radiation, and does not limit output. The graph indicated by the broken line in FIG. 2A is a clear example and illustrates the change in output when the output of the solar power generation device 3 reaches the rated power generation capacity.

  In the daytime when the output of the solar power generation device 3 exceeds the predetermined charge / discharge switching capacity Wb, the power storage device 5 charges the excess power via the system bus (power line 1), and this is charged at night. A so-called peak shift operation is performed in which power is supplied to the loads 2A, 2B and the like by discharging toward the system bus in the time zone. As a result, the combined output indicated by the graph indicated by the thick solid line in FIG. 2A is supplied to the load by both the solar power generation device 3 and the power storage device 5. Further, as shown in FIG. 2B, the power of the portion corresponding to the difference between the total demand and the combined output of the photovoltaic power generation device 3 and the power storage device 5 with a diagonal line in the lower right direction is adjusted power supply. The device 4 will share the output.

  FIG. 3 is a functional block diagram of the regulated power supply control device 44 according to the present embodiment. As shown in FIG. 3, the regulated power supply control device 44 is created in advance with a control computation device 441 that computes control commands such as power generation output commands, start / stop commands, operation mode change commands, etc. for the regulated power sources 41A to 41C. The operation pattern storage device 442 that holds various reference operation pattern groups of the independent operation type power supply system 10 and an operator to initially set and correct the reference operation pattern groups and to input operation commands for maintenance. The input device 443, the display device 444 for the operator to check the driving situation, the measurement information of the voltage / current detection device at the end, the measurement information of the solar radiation amount and the outside temperature of the measuring device 45 for estimating the driving state, And a measurement data storage device 446 that stores control commands, power generation output history, and the like, and control power supplies 41A to 41C (control units 411A to 41C). Configured and a signal output interface device (signal input and output I / F unit) 445 for controlling the transmission and reception of the control command and the measurement information to be transmitted to C, etc.).

  The control arithmetic device 441 includes an operation pattern control function 4411 and a frequency maintenance function 4412. The operation pattern control function 4411 includes an operation pattern selection unit 44111 that selects an optimum reference operation pattern from the reference operation pattern group held in the operation pattern storage device 442 based on its own measurement information, The operation state estimation unit 44112 that estimates the operation state and the total demand of the photovoltaic power generation device 3 and the power storage device 5 using the measurement information of the solar power generation device 3 and the power storage device 5 And an operation pattern correction unit 44113 for correcting based on the estimation result of the state and the total demand.

Further, the frequency maintaining function 4412 calculates a frequency deviation ΔF _G compensated by the output control of the regulated power supply device 4 and a frequency deviation ΔF _B compensated by the charge / discharge control of the power storage device 5 from the voltage measurement information at its own end. a calculation unit 44121, operates the power supply and load limit of operating governor-free in such a regulated power supply 41A~41C performed decrease determination of power supply capacity to perform the governor-free operation for frequency maintenance by using a frequency deviation [Delta] F _G power the operation mode setting unit 44122 to determine the bets, estimates the frequency control state of the power storage device 5 by using the frequency deviation [Delta] F _B, changes the frequency control constant of the regulated power supply device 4, if necessary frequency control constant changing unit 44123 And have.

  FIG. 4 is a functional block diagram of the power storage device control device 54 according to the present embodiment. As shown in FIG. 4, the power storage device control device 54 is created in advance with a control arithmetic device 541 that calculates control commands such as charge / discharge commands, start / stop commands, and operation mode change commands for the storage batteries 51 </ b> A and 51 </ b> B. An operation pattern storage device 542 for holding various reference operation pattern groups of the independent operation type power supply system 10 and an operator for initial setting / correction of the reference operation pattern groups and for inputting an operation command for maintenance An input device 543, a display device 544 for the operator to check the driving situation, measurement information of the voltage / current detection device at its own end, measurement information of the solar radiation amount and the outside air temperature of the measuring device 55 for driving state estimation, and A measurement data storage device 546 for storing a control command, a charge / discharge history, etc., and storage batteries 51A, 51B, etc. (power converters 52A, 52B for interconnection, etc.) Configured and a signal output interface device (signal input and output I / F unit) 545 for controlling the transmission and reception of the control command and the measurement information to be transmitted to.

  The control arithmetic device 541 includes an operation pattern control function 5411, a frequency maintenance function 5412, and an SOC adjustment function 5413. Here, SOC (State Of Charge) is an index that represents the remaining amount (charged electric energy) of the storage battery, and is expressed, for example, as a percentage of the rated charge capacity. The operation pattern control function 5411 includes an operation pattern selection unit 54111 that selects an optimum reference operation pattern from the reference operation pattern group held in the operation pattern storage device 542 based on its own measurement information, The operation state estimation unit 54112 that estimates the operation state and the total demand of the photovoltaic power generation device 3 and the regulated power supply device 4 using the measurement information of the solar power generation device 3 and the regulated power supply device 4 And a charge / discharge pattern correction unit 54113 for correcting based on the estimation results of the operating state and the total demand.

Further, the frequency maintaining function 5412 calculates a frequency deviation ΔF _B compensated by charge / discharge control of the power storage device 5 and a frequency deviation ΔF _G compensated by output control of the adjustment power supply device 4 from the voltage measurement information at its own end. deviation has a calculation unit 54121, and a frequency control constant changing unit 54122 estimates the frequency control state of the regulated power supply device 4 with a frequency deviation [Delta] F _G, of changing the frequency control constant of the electric storage device 5 if necessary. The SOC adjustment function 5413 calculates the charge / discharge amount for returning the SOC to the normal range based on the determination result, and the SOC determination unit 54131 that determines whether the storage batteries 51A, 51B, etc. are in the normal range by monitoring the SOC. And an SOC increase / decrease command generation unit 54132 to be generated.

  FIG. 5 is a flowchart showing a flow of control processing in the adjusted power supply control device 44. Hereinafter, the control in the regulated power supply control device 44 will be described with reference to FIG.

  First, in step S <b> 51, the adjusted power supply control device 44 reads a reference operation pattern group created in advance using the season, weather, outside temperature, and the like as parameters and held in the operation pattern storage device 442. Here, it is assumed that data of each reference operation pattern is created in units of 30 minutes by dividing one day into 48.

  The processing from step S52 to S58 described below is processing that is repeatedly executed by the operation pattern control function 4411. The execution cycle is, for example, several minutes to 30 from the relationship with the time resolution of the data of the reference operation pattern. It shall be set to the range of minutes. Here, the description will be made assuming that the execution cycle is 10 minutes. Further, the processing from step S59 to S61 is processing repeatedly executed by the frequency maintenance function 4412, and the execution cycle is set to 1 second or less.

In step S52, the driving pattern control function 4411 measures the solar radiation amount Sr (W / m ² ) and the outside air temperature To (° C.) that are periodically measured by the driving state estimation measuring device 45 and processed as an average value for 10 minutes. Are read from the measurement data storage device 446. Next, in step S53, using the solar radiation amount Sr (t) and the outside air temperature To (t) at the processing time t read in step S52 and the calendar information held in advance, the independent operation type power supply system 10 is operated. Various flags for selecting an optimum reference operation pattern, that is, a seasonal flag, a PV (Photovoltaic) flag, a temperature flag, and a storage battery flag are set.

The season flag is a flag for setting the season, and can be set uniquely from the calendar information and the processing time t. The PV flag is a flag for setting the power generation pattern of the solar power generation device 3, and as shown in FIG. 6A, the measured solar radiation amount Sr (t) and 24 hours defined for each season. The flag value is set according to Equation (1) using the reference value Sr_ref (t) of the solar radiation amount.
[PV flag]
When Sr (t)> Sr_ref (t), the flag value is set to “F”. When Sr (t) ≦ Sr_ref (t), the flag value is set to “C / R” (1)

  The flag value “F” is fair and the photovoltaic power generation device 3 is in a high power generation state, and the flag value “C / R” is cloudy (Rainy) or rainy (Rainy). It means that it is in a low power generation state.

The temperature flag is a flag for setting a power demand pattern such as the loads 2A and 2B. As shown in FIG. 6B, the outside temperature To (t) and the 24 hours defined for each season. The flag value is set according to the equation (2) using the reference value To_ref (t) of the outside air temperature for minutes.
[Temperature flag]
When To (t)> To_ref (t), set the flag value to “H”. When To (t) ≦ To_ref (t), set the flag value to “L”. (2)

  The flag value “H” is, for example, a state in which the temperature is high in the season (High) and the power demand for cooling is large, and the flag value “L” is in the season because the temperature is low (Low). This means that the electricity demand is small.

  Further, the storage battery flag is set to “R” (Refresh) if the day is a day for performing refresh charging of any storage battery based on the calendar information, and a flag value if the day is a normal charging / discharging operation. Set to “N” (Normal).

  Next, in step S54, using the various flags set in step S53, the optimal operation pattern number is selected based on the classification table of the reference operation pattern of the independently operated power supply system 10 illustrated in FIG. To do. The classification table illustrated in FIG. 7 can appropriately increase or decrease the number of classification categories of the season flag, the PV flag, and the temperature flag according to the characteristics of the region where the independently operated power supply system 10 is operated. The example of FIG. 7 assumes a region where the season flag is S1 to S4 and has four seasons in a temperate zone such as Japan. For example, depending on the region, the classification of the season flag may be classified into the rainy season, the dry season, etc. Two may be used.

Next, in step S55, the power generation output (PV output) of the solar power generation device 3, the charge / discharge amount of the power storage device 5, and the total demand are estimated using the measurement data of the solar radiation amount and the outside air temperature. Specifically, the power generation output Ppv (t) of the solar power generation device 3 is calculated by the equation (3) using the solar radiation amount measurement value Sr (W / m ² ) and the outside air temperature measurement value To (° C.). .
[Power generation output of solar power generator]
Ppv (t) = Sr (t) · Ks · Kpv · Kt (To) · Kb · Kc · Kpcs
× 10-3 (kW) (3)
However,
Ks: Solar radiation correction coefficient Kpv: Panel capacity conversion coefficient Kt (To): Temperature correction coefficient Kb: Dirt coefficient Kc: Cable efficiency coefficient Kpcs: Power conversion efficiency coefficient

The total demand (demand power for the loads 2A, 2B, etc.) Pd (t) is expressed by using the difference between the reference value To_ref (t) and the measured value To (t) of the outside air temperature and the demand pattern Pd_ptrn (t). Calculate by (4).
[Total demand]
Pd (t) = Pd_ptrn (t) + Cw × (To (t) −To_ref (t)) (4)
However, Cw: outside air temperature correction coefficient Here, Cw is a coefficient previously determined for each season from the relationship between the demand power and the actual outside air temperature in the system.

In addition, regarding the charge / discharge amount Pb (t) of the power storage device 5 (a positive value indicates discharge and a negative value indicates charge), the power generation output of the solar power generation device 3 is charged in the daytime and discharged at nighttime. The difference between the estimated value Ppv (t) of the photovoltaic power generation output and the reference output pattern Ppv_ptrn (t) of the photovoltaic power generation device 3 selected in step S54 is based on the operation pattern (see FIG. 2A). And calculated by the equation (5).
[Charge / discharge amount of power storage device]
Pb (t) = Pb_ptrn (t) − (Ppv (t) −Ppv_ptrn (t)) (5)

Next, in step S56, the power generation output Ppv (t), the total demand Pd (t) of the solar power generation device 3 estimated by the equations (3) to (5), and the charge / discharge amount Pb (t) of the power storage device 5 are calculated. ) Is used to re-select the optimum operation pattern of the adjusted power supply device 4 held in advance from the necessary combined power generation output Pg (t) of the adjusted power supply device 4 calculated by the equation (6) using Correct the output command value.
[Necessary combined power generation output of regulated power supply]
Pg (t) = Pd (t) − (Ppv (t) + Pb (t))
= Pd (t)-(Ppv_ptrn (t) + Pb_ptrn (t)) (6)

  In step S57, if requested by the frequency maintenance function 4412, the output command to the adjustment power sources 41A to 41C is corrected again in consideration of the increase / decrease in the number of adjustment power sources for governor-free / load limit operation, and then continued. In step S58, control commands such as a start / stop command, an operation mode change command, and an output command value are transmitted to the control units 411A to 411C of each adjustment power source via the signal input / output interface device 445.

  Next, the control process of the frequency maintenance function 4412 performed in parallel with the process of the operation pattern control function 4411 will be described. First, in step S59, the voltage measurement value at its own end, which is always measured, is read, the frequency F of the system bus (power line 1) is calculated, and the frequency deviation ΔF from the rated frequency Fo is calculated.

Next, in step S60, inputs the frequency deviation [Delta] F to the cut-off frequency fc of the low-pass filter LPF (Low Pass Filter), we obtain the frequency deviation [Delta] F _G to compensate by adjusting the power supply 4. Also, enter the frequency deviation [Delta] F to the cutoff frequency fc of the high pass filter HPF (High Pass Filter), the electric storage device 5 calculates the frequency deviation [Delta] F _B to compensate. The cut-off frequency fc of the low-pass filter LPF and the high-pass filter HPF is set to the control units 411A to 411C such as the adjustment power supplies 41A to 41C and the power converters 52A and 52B for the interconnection of the power storage device 5 It is the same value, and is set to about 0.01 Hz, for example, so that the power storage device 5 compensates for the frequency fluctuation of several seconds to several tens of seconds, which is the output fluctuation period of the photovoltaic power generation panels 31A and 31B.

Next, in step S61, exceeds the power output threshold (some of such 41A, 41B, 41C) governor-free operation to have regulated power supply, and the frequency deviation [Delta] F _G exceeds the threshold value [Delta] F _G _ref If the state continues beyond a predetermined time, it is determined that the governor-free capacity is insufficient, and the number of adjustment power supplies for governor-free operation is increased. In addition, if there are two or more regulated power supplies in governor-free operation, the average value of the power generation output is less than the threshold value, and ΔF _G is less than the threshold value ΔF _G _ref for more than a predetermined time, the governor Reduce the number of adjustment power supplies in free operation by one. Further, when the frequency deviation ΔF _B compensated by the power storage device 5 exceeds a predetermined time and exceeds the threshold value ΔF _B _ref, it is determined that the power storage device 5 has become incapable of frequency control, and is set in the control units 411A to 411C of the adjusted power source. and by disabling the low pass filter LPF has a frequency deviation [Delta] F _B to be compensated by the energy storage device 5 also together by changing the frequency control constants to compensate by adjusting the power supply device 4, stable operation of independent operation type power supply system 10 To maintain.

  FIG. 8 is a flowchart showing the flow of control processing in the power storage device control device 54, and the basic flow of processing is substantially the same as that of the adjusted power supply control device 44 in FIG. Hereinafter, the control in the power storage device control device 54 will be described with reference to FIG.

  First, in step S <b> 81, the power storage device control device 54 reads a reference operation pattern group that is created in advance using parameters such as season, weather, and temperature as parameters and stored in the operation pattern storage device 542. Here, it is assumed that data of each reference operation pattern is created in units of 30 minutes by dividing one day into 48.

  The processing from step S82 to S87 described below is processing that is repeatedly executed by the operation pattern control function 5411 and the SOC adjustment function 5413, and the execution cycle thereof is based on the relationship with the time resolution of the data of the reference operation pattern. For example, it shall be set in the range of several minutes to 30 minutes. Here, the description will be made assuming that the execution cycle is 10 minutes. Further, the processing from step S88 to S90 is processing repeatedly executed by the frequency maintaining function 5412, and the execution cycle is set to 1 second or less.

  The processing from step S82 to S84 in FIG. 8 is exactly the same as the processing from step S52 to S54 in FIG.

In the next step S85, the power generation output of the solar power generation device 3 is estimated using the measurement data of the solar radiation amount and the outside air temperature. Specifically, the power generation output Ppv (t) of the solar power generation device 3 is obtained by the above equation (3) using the solar radiation measurement value Sr (W / m ² ) and the outside air temperature measurement value To (° C.). calculate.

Next, in step S86, the power generation output Ppv (t) of the solar power generation device 3 estimated in step S85 and the reference output of the solar power generation device 3 assumed in the reference operation pattern selected in step S84. Using the difference from the pattern Ppv_ptrn (t), the charge / discharge amount Pb (t) of the power storage device 5 is calculated by the above equation (5). In addition, if the SOC level P _SOC (t) of each of the storage batteries 51A, 51B, etc. exceeds a threshold value P _{SOC_UL} set in the vicinity of the allowable upper limit value, an expression (in order to reduce the SOC level) Correction is made using equation (7) in which a correction term is added to 5).
[Charge / discharge amount of power storage device (when correcting SOC level reduction)]
Pb (t) = Pb_ptrn (t) − (Ppv (t) −Ppv_ptrn (t))
+ K _soc · (P _SOC (t) −P _{SOC_UL} ) (7)
K _soc : SOC correction coefficient

Further, if the SOC level P _SOC (t) of each of the storage batteries 51A, 51B, etc. falls below the threshold value P _{SOC_LL} set near the allowable lower limit value, the equation (5) is set so as to increase the SOC level. Correction is performed using equation (8) with a correction term added.
[Charge / discharge amount of power storage device (when correcting SOC level increase)]
Pb (t) = Pb_ptrn (t) − (Ppv (t) −Ppv_ptrn (t))
_{-K soc · (P SOC_LL (t} ) -P SOC) (8)
K _soc : SOC correction coefficient

  In this way, it is possible to prevent the SOC level of the storage batteries 51A, 51B, etc. from deviating from the predetermined operating range, so that the system can be operated stably due to the inability to charge / discharge the storage battery, or the battery due to overcharge or overdischarge. The adverse effect on the life can be reduced.

  Next, in step S87, control commands such as a charge / discharge command, a start / stop command, and an operation mode change command are transmitted to the interconnection power converters 52A, 52B and the like via the signal input / output interface device 545.

  Next, control processing of the frequency maintenance function 5412 that is performed in parallel with the processing of the operation pattern control function 5411 and the SOC adjustment function 5413 will be described.

  The processing in steps S88 and S89 in FIG. 8 is exactly the same as the processing in steps S59 and S60 in FIG.

In the next step S90, when the frequency deviation ΔF _G compensated by the adjustment power supply device 4 exceeds a predetermined time and exceeds the threshold value ΔF _G _ref, it is determined that the adjustment power supply device 4 has become unable to control the frequency, and the power storage device 5 is connected. system for power converter 52A, and disables the high-pass filter HPF is set to 52B, etc., the frequency deviation [Delta] F _G to be compensated by adjusting the power supply device 4 also together by changing the frequency control constants to compensate in the battery 5 The stable operation of the independent operation type power supply system 10 is maintained.

  Next, a method of creating a reference operation pattern group that is stored in advance in the operation pattern storage devices 442 and 542 of the adjusted power supply control device 44 and the power storage device control device 54 will be described with reference to FIG. FIG. 9 is a flowchart exemplifying a procedure for creating a reference operation pattern group of the independently operated power supply system 10.

  First, in step S <b> 91, device characteristics and related parameters of the solar power generation device 3, the regulated power supply device 4, and the power storage device 5 that configure the independently operated power supply system 10 are set. For the solar power generation device 3, for example, characteristics and parameters such as device type and number, rated output (kW), solar radiation characteristics, temperature characteristics, power conversion efficiency (%), and the like can be given. In addition, for the regulated power supply device 4, for example, the device type and number, rated output (kW), fuel efficiency (%), minimum operation output (kW), output change rate upper limit value (kW / s), fuel unit price (¥) / m3) and other characteristics and parameters. For the power storage device 5, for example, the device type and number, rated output (kW), rated capacity (kWh), SOC upper limit value (%), SOC lower limit value (%), charge / discharge amount change rate upper limit value (% / s), charge / discharge efficiency (%), auxiliary power consumption rate (%), and other characteristics and parameters.

Next, in step S92, an objective function for obtaining a reference operation pattern is selected. For example, the objective function f for minimizing the operating cost can be defined as in Expression (9).
[Objective function]
f = (Operating cost of the regulated power supply) + (Power consumption cost of the auxiliary storage battery) (9)
here,
Operating cost of the regulated power supply = (Unit price of the regulated power supply (\ / kWh)) / (Power generation amount of the regulated power supply (kWh))
= Fuel unit price (\ / m ³ ) / (Power generation energy of fuel (kWh / m ³ ) / Fuel efficiency (%))
・ ((Demand energy (kWh))-(Power generation amount of photovoltaic power generation equipment (kWh))))
Power consumption of storage battery auxiliary equipment
= Charge / discharge energy (kWh), auxiliary machine power consumption rate (%), system average power generation unit price (\ / kWh)

  Next, in step S93, the total demand pattern and the photovoltaic power generation pattern for one day corresponding to each classification condition for obtaining the reference operation pattern, that is, the combination of the values of the season flag, the PV flag, and the temperature flag are respectively set to 30. Set an average value in minutes. It is desirable to create and set these patterns from actually measured data. However, if there is no measured data, the default value is calculated from the capacity and type of load equipment as the default value. The amount of power generated by solar power generation is determined by calculating the amount corresponding to the measurement value of solar radiation amount Sr using the latitude of the solar power generation panel group 31A, 31B, etc., and the solar radiation transmittance according to the weather. The value calculated using equation (3) can be used. Subsequently, in step S94, conditions such as presence / absence of refresh charging of the storage batteries 51A, 51B, etc. are input as the operating conditions for the target day.

Next, in step S95, constraint conditions such as Expressions (10) and (11) to be satisfied by the regulated power supply device 4 and the power storage device 5 are set.
[Restrictions on regulated power supply]
When the power generation output of the regulated power source i at time t is P _{G —} i (t),
P _{G — i} (t) = 0 or P _{G — i} (t)> Minimum power generation output | P _G — _i (t) −P _G — _i (t−1) | <Output change rate upper limit (10)
[Restrictions on power storage devices]
When the SOC of the storage battery i at time t is SOC_i (t) and the charge / discharge amount is P _{b_i} (t),
Lower threshold <SOC_i (t) <upper limit threshold value _{| P b_i (t) -P b_i} (t-1) | < discharge amount change rate upper limit (11)

  Next, in step S96, an optimization operation for minimizing the objective function f shown in equation (9) is performed under the constraint conditions set in equations (10) and (11). In the objective function f of Expression (9), the fuel efficiency generally has a nonlinear characteristic with respect to the output of the regulated power supplies 41A to 41C and the like. Here, since it is necessary to create a more economical standard operation pattern, a method that can deal with nonlinear optimization problems such as genetic algorithms is applied so that these nonlinear characteristics can be closely simulated. Is preferred.

  FIG. 10 shows an example of the optimum reference operation pattern created in step S96. This example is an example of the reference operation pattern for the classification condition when the solar radiation condition is clear (PV flag is “F”) and the storage battery is not refresh-charged (storage battery flag is “N”). In addition, about allocation of each operation pattern when adjustment power supplies 41A-41C etc. have the same specification, so that the maintenance period of a specific device may not become short by variation of each operation time, For example, it is desirable to set the calendar information so that the device number is rotated in a cycle of one week.

  The processes from step S93 to S96 are repeatedly executed for all the classification conditions of the reference operation pattern illustrated in FIG. 7, and the process ends when the generation of the operation patterns for all the classification conditions is completed.

  As described above, according to the present embodiment, each of the devices constituting the independently operated power supply system uses the information on the reference operation pattern that minimizes the operation cost set in advance according to the operation environment of the system. Since each device operates by correcting its own reference operation pattern using its own measurement information, each device operates using only its own information, and is stable and economical. Operation can be realized. More specifically, since the fuel consumption for operating the regulated power supply can be reduced, the total power generation cost including the transportation cost can be reduced. In addition, because renewable energy from solar power generation can be used effectively, CO2 emissions can be reduced, and the system can be operated without communication equipment, reducing installation costs and changing the configuration such as adding equipment. This also has the effect of facilitating.

  Although the description of the mode for carrying out the present invention has been described above, the embodiment of the present invention is not limited to this, and various modifications can be made without departing from the spirit of the present invention.

1 Power line (system bus)
10 Independently operated power supply system (power supply system)
2A, 2B Load 3 Photovoltaic power generation device 31A, 31B Photovoltaic power generation panel 32A, 32B, 52A, 52B Power converter for interconnection 33A, 33B, 43A, 43B, 43C, 53A, 53B Power reception equipment for interconnection 4 Adjustment power supply Apparatus 41A, 41B, 41C Adjustment power supply 411A, 411B, 411C Control unit 44 Adjustment power supply control apparatus (control apparatus of adjustment power supply apparatus)
441, 541 Control arithmetic unit (control unit)
442, 542 Operation pattern storage device (storage unit)
443, 543 Input device 444, 544 Display device 445, 545 Signal input / output interface device 446, 546 Measurement data storage device
45,55 Measuring device for driving state estimation (Measuring means for solar radiation and ambient temperature)
5 Power Storage Device 51A, 51B Storage Battery 54 Power Storage Device Control Device (Control Device for Power Storage Device)

Claims (10)

A solar power generation device connected to a system bus, a regulated power supply device, and a power storage device, an independently operated power supply system that supplies power to a load connected to the system bus,
Each of the adjustment power supply device and the power storage device control device includes:
A storage unit that stores a reference operation pattern group that defines an output sharing of each device, which is created in advance for each of predetermined classification conditions uniquely determined by calendar information and own measurement information,
Select a reference operation pattern for the current classification condition corresponding to the current date and time and current measurement information from the group of reference operation patterns,
By correcting the output sharing determined by the selected reference operation pattern using the current own end measurement information, the corrected output sharing of the control target device of the own device is calculated, and the calculated post-correction And a control unit that controls the operation of the device to be controlled based on the output sharing of the power supply system. The power supply system according to claim 1,
Each of the regulated power supply device and the power storage device includes a means for measuring the amount of solar radiation and the outside air temperature,
An electric power supply system using an amount of solar radiation and an outside air temperature measured by the measuring means as the measurement information of the own end. A solar power generation device connected to a system bus, a regulated power supply device, and a power storage device, an independently operated power supply system that supplies power to a load connected to the system bus,
Each of the adjustment power supply device and the power storage device control device includes:
A storage unit that stores a reference operation pattern group that defines an output sharing of each device, which is created in advance for each classification condition in which the season, the outside air temperature, the amount of solar radiation, and the like are divided and combined,
Select a reference operation pattern for the current classification condition that combines the current season category and the category corresponding to the current outside air temperature and solar radiation measurement information from the reference operation pattern group,
By correcting the output sharing determined by the selected reference operation pattern using the current outside air temperature and the measurement information of the solar radiation amount, the output sharing after correction of the control target device of the own device is calculated. And a control unit that controls the operation of the device to be controlled based on the calculated output sharing after correction. The power supply system according to any one of claims 1 to 3,
The adjustment power supply device includes a plurality of adjustment power supplies,
The said control apparatus of the said adjustment power supply apparatus controls the number of the said adjustment power supplies which carry out governor free operation based on the output share after the correction | amendment. The power supply system according to any one of claims 1 to 3,
When the SOC level of the storage battery controlled by the power storage device is higher than a predetermined upper limit threshold, the control device of the power storage device corrects the output sharing so as to lower the SOC level of the storage battery, and controls the storage battery controlled by the power storage device. When the SOC level is lower than a predetermined lower threshold, the output sharing is corrected so as to increase the SOC level of the storage battery. In the electric power supply system according to any one of claims 1 to 5,
Each of the adjustment power supply device and the control device of the power storage device includes means for maintaining an output frequency at a rated frequency,
The control device of the adjustment power supply device compensates for a frequency deviation of a component lower than a predetermined cutoff frequency, and the control device of the power storage device compensates for a frequency deviation of a component higher than the predetermined cutoff frequency. A power supply system characterized by: The power supply system according to claim 6, wherein
The control device of the regulated power supply device uses the predetermined cutoff frequency when a frequency deviation of a component higher than the predetermined cutoff frequency to be compensated for by the control device of the power storage device is not compensated for a predetermined time or more. A power supply system which compensates for all frequency deviations including frequency deviations of higher components. The power supply system according to claim 6, wherein
When the frequency deviation of a component lower than the predetermined cut-off frequency to be compensated for by the control device of the regulated power supply device is not compensated for a predetermined time or more, the control device of the power storage device uses the predetermined cut-off frequency. A power supply system for compensating for all frequency deviations including frequency deviations of lower components. The power supply system according to any one of claims 1 to 8,
Each of the adjustment power supply device and the control device of the power storage device,
The power supply system, wherein the selection of the reference operation pattern and the correction of the output sharing are repeatedly executed at a predetermined cycle. In the electric power supply system according to any one of claims 1 to 9,
The reference operation pattern group that is stored in advance in the storage unit of each of the adjustment power supply device and the control device of the power storage device is a non-linear that minimizes the operation cost of the system while satisfying the constraint condition related to the stable operation of the system A power supply system created by solving an optimization problem.

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