JP7313301B2 - Power system supply and demand adjustment device, power system load frequency control device, power system balancing group device, and power system supply and demand adjustment method - Google Patents

Description

The present invention relates to a supply and demand adjustment device for an electric power system, a load frequency control device for an electric power system, a balancing group device for an electric power system, and a supply and demand adjustment method for an electric power system.

Frequency fluctuations occur when a demand-supply imbalance occurs in a power system due to load fluctuations or the like. In load frequency control (hereinafter referred to as LFC), for load fluctuations (including renewable energy fluctuations) of several minutes to 20 minutes, the central load dispatching center calculates the amount of load fluctuations, and by commanding each generator to generate power following this load fluctuation amount, the system frequency is suppressed to the allowable range. By defining this load fluctuation amount as an Area Requirement (hereafter sometimes referred to as AR) and issuing an output command to the generator so as to satisfy this AR, the supply and demand balance can be maintained.

The output command is not issued to all generators, but is issued to generators whose output can be changed in short cycles. In normal operation, about 1 to 2% of the system capacity is secured for the load fluctuation adjustment capability of several minutes to 20 minutes. Each interconnected power system mainly employs the following two LFC methods.

The first LFC system is a constant frequency control system (Flat Frequency Control: hereinafter referred to as FFC system). In the FFC method, the system frequency deviation Δf is detected, and a generator output command is sent to the LFC target generator to reduce the system frequency deviation Δf, thereby maintaining the frequency at a specified value.

The second LFC system is a frequency bias tie line power flow control system (Tie Line Bias Control, hereinafter referred to as TBC system). In the TBC method, the system frequency deviation Δf and the interconnection line power flow deviation ΔPt are detected, and the generator output command is sent to the LFC target generator to reduce the value determined by the system frequency deviation Δf and the interconnection line power flow deviation ΔPt. AR in the TBC method is calculated by the following equation (1). (1) In the formula, K is a systematic constant. In addition, in the FFC method, AR is calculated by omitting the interconnection line power flow deviation ΔPt from the equation (1) of the TBC method.
AR=−K×Δf+ΔPt (1)

Supply and demand are balanced by allocating the AR calculated by the formula (1) to the thermal power generator or the hydroelectric power generator for each output change rate. Here, if a large amount of renewable energy such as photovoltaic power generation and wind power generation is introduced into the electric power system, and the resulting imbalance between supply and demand increases, there is a risk that frequency fluctuations cannot be prevented.

In addition, when a supply and demand adjustment market for trading of balancing capacity is established, general power transmission and distribution companies will procure balancing capacity in this supply and demand balancing market. In addition, in its operation, there is a possibility that a mechanism for activating the adjustment power based on the merit order rather than for each output change rate may be provided. In the AR allocation by the merit order method, the AR is allocated to the LFC target generators based on the priority based on the fuel cost. In the direction of increasing the control force, the AR is distributed in descending order of fuel cost, and in the direction of decreasing the control force, the AR is allocated in descending order of fuel cost. However, allocation based on the merit order may reduce the number of generators to which AR is allocated and increase frequency fluctuations.

There is a technique disclosed in Patent Literature 1 as a supply and demand adjustment method for an electric power system. According to Patent Document 1, a method of determining ACE allocation to LFC target generators by changing target zones according to zones for each size of area control error (supply and demand imbalance is also referred to as AR, which means the amount to be adjusted in output, or area control error (hereinafter referred to as ACE), which means the amount that could not be controlled in the area) is described.

U.S. Patent Application Publication No. 2016/0149409

However, in Patent Document 1, it may be difficult to determine the ACE zone so that the fuel cost can be reduced while maintaining the system frequency within the management target value.

The present invention has been made in view of the above problems, and it is an object of the present invention to provide a power system supply and demand adjustment device, a power system load frequency control device, a power system balancing group device, and a power system supply and demand adjustment method that can reduce costs while suppressing frequency fluctuations according to load fluctuations.

In order to achieve the above object, the supply and demand adjustment device for an electric power system includes: an output allocable upper limit value changing unit that changes an output allocable upper limit value to a target control power supply per output allocation;

ADVANTAGE OF THE INVENTION According to this invention, cost can be reduced, suppressing the frequency fluctuation|variation according to a load fluctuation and an output fluctuation.

1 is a block diagram showing a hardware configuration of a load frequency control device for a power system connected to the power system according to the first embodiment; FIG. 1 is a block diagram showing a functional configuration of a load frequency control device for a power system according to Embodiment 1; FIG. 4 is a flow chart showing processing of the load frequency control device for the electric power system of the first embodiment; FIG. 10 is a diagram showing an example of a model representing the relationship between frequency fluctuation and the allocatable upper limit value, referred to by the allocatable upper limit value changing unit of the first embodiment; FIG. 10 is a diagram showing an example of frequency fluctuations referred to during output allocation by the supply and demand adjustment monitoring device for the electric power system according to the first embodiment; 4 is a diagram showing an example of output distribution for each adjustable power supply by the load frequency control device for the power system of the first embodiment; FIG. FIG. 4 is a diagram showing an example of time-series output changes in output distribution for each control power supply by the load frequency control device for the electric power system of the first embodiment; FIG. 11 is a block diagram showing a functional configuration of a load frequency control device for a power system according to a second embodiment; FIG. 10 is a diagram showing an example of a model showing the relationship between AR variation and the allocatable upper limit value, which is referred to by the allocatable upper limit value changing unit of the second embodiment; FIG. 10 is a diagram showing an example of AR fluctuations referred to during output distribution of the supply and demand adjustment monitoring device for a power system according to the second embodiment; FIG. 11 is a block diagram showing a functional configuration of a load frequency control device for a power system according to Embodiment 3; FIG. 11 is a diagram showing an example of a model representing the relationship between renewable energy output fluctuations and allocable upper limit values, which is referred to by an output allocable upper limit value changing unit of Example 3; FIG. 11 is a diagram showing an example of renewable energy output fluctuations referenced during output allocation by the supply and demand adjustment monitoring device for a power system according to the third embodiment; FIG. 11 is a block diagram showing a functional configuration of a power system balancing group device according to a fourth embodiment;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings. It should be noted that the embodiments described below do not limit the invention according to the scope of claims, and not all of the elements and combinations thereof described in the embodiments are essential to the solution of the invention.

In the drawings for explaining the embodiments, portions having the same functions are denoted by the same reference numerals, and repeated description thereof will be omitted.

In addition, in the following description, an expression such as "xxx data" may be used as an example of information, but information may have any data structure. That is, "xxx data" can be referred to as "xxx tables" to indicate that the information is independent of the data structure. Furthermore, "xxx data" may be simply referred to as "xxx". In the following description, the configuration of each information is an example, and the information may be divided and held or combined and held.

FIG. 1 is a block diagram showing the hardware configuration of a load frequency control device connected to a power system according to the first embodiment. In addition, in the first embodiment, an example in which a supply and demand adjustment device exists as a part of the components of the load frequency control device will be described.

In FIG. 1, the load frequency control device 10 is configured by, for example, a computer system. The load frequency control device 10 performs load frequency control to suppress frequency fluctuations caused by load fluctuations of the electric power system 20 or the like. At this time, the load frequency control device 10 calculates the amount of load fluctuation for a load fluctuation of about several minutes to 20 minutes, and commands the adjustment power supply to follow the amount of load fluctuation, thereby suppressing the system frequency within the allowable range. In this specification, a distribution destination of output distribution in load frequency control is referred to as a control power supply. The regulating power source can be selected from at least one of a generator, a storage battery, and a demand response.

The load frequency control device 10 determines output distribution according to economic efficiency for the AR that defines the amount of load fluctuation. Output distribution according to economy is, for example, output distribution according to merit order. In merit order power allocation, the load frequency controller 10 allocates AR to the regulating power supplies on a cost-based priority basis. At this time, the load frequency control device 10 can allocate the ARs in descending order of cost in the increasing direction of the adjusting force, and allocate the ARs in descending order of cost in the decreasing direction of the adjusting force. The cost referred to here may include the procurement cost in addition to the fuel cost of the regulating power supply.

The load frequency control device 10 can access measurement information and the like of the power system 20 via the communication network 300 . The electric power system 20 is a system in which a plurality of generators 23A to 23D and loads 25A, 25B, 25D to 25F are interconnected via buses (nodes) 21A to 21F, transformers 22A to 22D and transmission lines (branches) 24A to 24E. The generators 23A to 23D referred to here are, for example, thermal power generators, hydraulic power generators, or nuclear power generators. Various measuring instruments for protection, control and monitoring of the power system 20 are installed in the nodes 21A to 21F. Storage batteries 26A-26D and renewable energy generators 27A-27D are connected to the respective nodes 21A-21D. Renewable energy generators 27A-27D are, for example, photovoltaic generators, solar thermal generators or wind generators.

The load frequency control device 10 includes a display section 21 , an input section 22 , a communication section 23 , a processor 24 , a memory 25 and a storage device 26 . Display unit 21 , input unit 22 , communication unit 23 , processor 24 , memory 25 and storage device 26 are connected via bus 27 .

The display unit 21 displays parameters handled by the load frequency control device 10, processing results of the load frequency control device 10, and the like. The display unit 21 may be a display device, or a printer device, an audio output device, or the like may be used together with the display device.

The input unit 22 inputs various conditions for operating the load frequency control device 10 . The input unit 22 can use a keyboard, a mouse, and the like, and may include at least one of a touch panel, a voice instruction device, and the like.

The communication unit 23 has circuits and communication protocols for connecting to the communication network 300 . The communication network 300 may be a WAN (Wide Area Network) such as the Internet, a LAN (Local Area Network) such as WiFi or Ethernet (registered trademark), or a mixture of WAN and LAN.

The processor 24 executes computer programs, searches data in various databases stored in the storage device 26 , instructs display of processing results, performs processing related to load frequency control of the electric power system 20 , and the like. The processor 24 may be a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit). Processor 24 may be a single-core processor or a multi-core processor. Processor 24 may include a hardware circuit (eg, FPGA (Field-Programmable Gate Array) or ASIC (Application Specific Integrated Circuit)) that performs part or all of the processing. Processor 24 may comprise a neural network. Processor 24 may be configured as one or more semiconductor chips, or may be configured as a computing device such as a computing server. Execution of the program may be shared among multiple processors or computers. Alternatively, the processor 24 may instruct a cloud computer or the like via the communication network 300 to execute all or part of the load frequency control program and receive the execution result.

The memory 25 is configured as, for example, a RAM (Random Access Memory), stores computer programs and calculation result data, and provides the processor 24 with a work area required for each process.

The storage device 26 is a storage device having a large storage capacity, such as a hard disk device or an SSD (Solid State Drive). The storage device 26 can hold executable files of various programs and data used for executing the programs. The storage device 26 can hold a past data database (database: DB) DB1, an output allocable upper limit database DB2, and an output allocation command value database DB3. The storage device 26 can also hold a load frequency control program. The load frequency control program may be software that can be installed in the load frequency control device 10, or may be incorporated in the load frequency control device 10 as firmware.

The past data database DB1 stores past data such as control power output and renewable energy output.

The allocable upper limit value database DB2 stores a function indicating the relationship between the frequency fluctuation and the allocable upper limit value.

The output distribution command value database DB3 stores output distribution command values for each adjustable power source.

1 shows an example in which the load frequency control device 10 holds the past data database DB1, the allocatable upper limit value database DB2, and the output allocation command value database DB3, but at least one of the past data database DB1, the allocatable upper limit value database DB2, and the output allocation command value database DB3 may be held in a cloud server.

FIG. 2 is a block diagram of a functional configuration of the load frequency control device according to the first embodiment; In the following description, when the operator is described as "Part XX", the processor 24 in FIG.

In FIG. 2, the load frequency control device 10 includes a power system supply and demand adjustment device 11, an output distribution command value database DB3, an AR calculation unit 14, and an output distribution unit 15 according to the merit order.

2, the supply and demand adjustment device 11 includes a past data database DB1, an allocatable upper limit value database DB2, a supply and demand analysis unit 12, and an allocatable upper limit value changing unit 13. FIG.

The AR calculation unit 14 receives the system frequency deviation Δf and the interconnection line power flow fluctuation ΔPt as inputs, calculates the AR, and outputs it to the output distribution unit 15 according to the merit order. The AR calculation unit 14 can use the formula (1) to calculate the AR. In the calculation of AR, both of the system frequency deviation Δf and the interconnection line power flow deviation ΔPt may be used, or either one of them may be used.

The FFC method or the TBC method may be used to calculate the AR. In the TBC method, AR can be calculated from equation (1). In the FFC method, the AR can be calculated by omitting the interconnection line power flow deviation ΔPt from the TBC method equation (1). Of the system frequency deviation Δf and the interconnection line power flow deviation ΔPt, only the system frequency deviation Δf may be used to calculate AR.

The output allocatable upper limit changing unit 13 determines the output allocatable upper limit according to the merit order of the AR calculated by the AR calculator 14 .

Here, the allocatable output upper limit changing unit 13 can change the allocatable upper limit value according to the merit order based on the frequency fluctuation of the electric power system 20 . This frequency variation can be given by a system frequency deviation Δf. At this time, the allocatable upper limit value changing unit 13 refers to the allocatable upper limit value database DB2, and can change the allocatable upper limit value according to the merit order according to the frequency change according to the output allocatable upper limit change model that indicates the relationship between the frequency change and the allocatable upper limit value.

Alternatively, the allocatable output upper limit changing unit 13 may change the allocatable upper limit of output according to the merit order based on the power flow deviation ΔPt of the interconnection line. At this time, an output allocatable upper limit value model indicating the relationship between the interconnection line power flow deviation ΔPt and the allocatable upper limit value can be registered in the allocatable upper limit value database DB2.

The output allocating unit 15 according to the merit order determines the output allocation to the adjustable power source based on the allocable output upper limit determined by the output allocable upper limit changing unit 13 .

Regarding the command method (command value or pulse) for output distribution described above, although there are many methods for transmitting the distribution target and the command value, it is not limited to a specific system.

FIG. 3 is a flow chart showing processing of the load frequency control device of FIG.

3, in step S1, the AR calculator 14 of FIG. 2 calculates AR based on the system frequency deviation Δf and the interconnection line power flow fluctuation ΔPt.

Next, in step S2, the allocatable upper limit changing unit 13 determines the output allocation according to the merit order based on the AR calculated by the AR calculating unit 14, the system frequency deviation Δf input from the outside, and the allocatable upper limit model stored in the allocable upper limit database DB2. At this time, for the AR calculated by the AR calculation unit 14, the output allocatable upper limit changing unit 13 can determine the output distribution according to the merit order while keeping the system frequency within the allowable range.

First, an example of a method for manually creating an output allocable upper limit model will be described.

FIG. 4 is a diagram showing an example of the relationship between the allocatable upper limit value and the allocable upper limit value according to the frequency fluctuation referred to by the allocatable upper limit value changer in FIG. 2 .

In FIG. 4, the output allocatable upper limit value database DB2 of FIG. 2 holds the function of the output allocatable upper limit value. This output allocable upper limit is decreased as the frequency fluctuation increases.

For example, when the frequency fluctuation is 0.00 Hz, the output allocable upper limit model sets the output allocable upper limit to the rated output. When the frequency variation is greater than 0.00 Hz and less than 0.10 Hz, the output allocation upper limit is set to a ratio greater than 0.0 and less than 1.0. When the frequency fluctuation is 0.10 Hz or more, the output allocable upper limit is set to the output changeable width per command cycle.

Note that the allocatable output upper limit changing unit 13 may determine the allocatable upper limit based on the result of referring to the allocatable upper limit in FIG. 4, or may switch the allocatable upper limit when the frequency exceeds the threshold. Also, the frequency threshold may be set in several stages.

Next, an example of a method for automatically creating an output allocable upper limit model will be described.

For example, past performance data (generator output, renewable energy output, frequency fluctuations, etc.) stored in the past data database and management target values such as frequency fluctuations (for example, Δf ± 0.1 Hz) are input, and by performing supply and demand analysis while changing the upper limit of possible output distribution as a parameter, the upper limit of possible output distribution that can be suppressed within the control target value for the original frequency fluctuation is calculated, and a regression model is created.

Next, in step S3, the output allocating unit 15 according to the merit order determines the output allocation according to the merit order to each adjustable power source based on the output allocable upper limit according to the merit order determined by the output allocable upper limit changing unit 13.

At this time, the output allocation unit 15 according to the merit order determines the output allocation of each control power supply according to the merit order so that the output allocation according to the merit order satisfies the regional demand. When the output distribution of each controllability power supply is determined according to the merit order, controllability can be allocated in order from the controllability power supply with the lowest cost within the range of restrictions that can be assigned to each controllability power supply. Regarding the decreasing direction of the control power, the control power can be allocated in order from the control power supply with the highest cost within the range of restrictions that can be assigned to each control power supply.

FIG. 5 shows an example of a method of referring to frequency fluctuations when determining the output allocable upper limit value of FIG. 3 .

In FIG. 5, the output allocable upper limit changing unit 13 in FIG. 2 monitors frequency fluctuations. The output allocable upper limit changing unit 13 determines the output allocable upper limit based on the instantaneous value of the frequency fluctuation. At this time, if the frequency variation is large, the allocable output upper limit value changing unit 13 decreases the allocable output upper limit value, and if the frequency variation is small, the output allocable upper limit value is increased.

For example, if the allocatable output upper limit changing unit 13 refers to the frequency variation at time t1 to determine the allocatable upper limit, the frequency variation at time t1 is 0.1, so the output allocatable upper limit corresponding to the frequency variation of 0.1 is obtained from the output allocatable upper limit value function of FIG. In the output allocatable upper limit value function of FIG. 4, the allocatable upper limit value corresponding to the frequency fluctuation of 0.1 is 1.0, so the allocatable upper limit value changing unit 13 sets the allocatable upper limit value to 1.0 according to the merit order.

At this time, the output allocable upper limit changing unit 13 can update the output allocable upper limit at a period shorter than the load fluctuation time of several minutes to 20 minutes assumed in LFC. For example, the output allocable upper limit changing unit 13 can update the output allocable upper limit at intervals of 5 seconds.

The width of the time period P11 can be set based on the load fluctuation time of several minutes to 20 minutes assumed in LFC.

Moreover, as described above, not only the method of monitoring the frequency fluctuation by the maximum value for the width of the time slot, but also the method of monitoring the frequency fluctuation by the standard deviation of the width of the time slot, or the like may be used.

FIG. 6(a) is a diagram showing an example of output distribution for each controllability power supply based on the output allocable upper limit (20 for each controllability power supply), and FIG. 6(b) is a diagram showing an example of output distribution for each controllability power supply based on the output allocable upper limit (10 for each controllability power supply).

In FIG. 6( a ), it is assumed that the output allocable upper limit value changing unit 13 of FIG. 2 has determined, for example, 20 for each adjustable power source with respect to the allocation target value of 40 for output allocation.

At this time, for example, the output distribution unit 15 according to the merit order allocates 10 to the control power source A with the lowest power generation cost. Furthermore, the output distribution unit 15 according to the merit order allocates 10 to the control power source B having the second lowest power generation cost.

For example, it is assumed that the allocation destinations of AR are control power sources A to E. At this time, it is assumed that the power generation costs MA to ME of the control power sources A to E satisfy MA<MB<MC<MD<ME. In addition, it is assumed that the output change speeds VA to VE of the control power sources A to E satisfy VA=VB=VC=VD=VE. It is also assumed that the AR value calculated by the AR calculation unit 14 is 40 as a constraint value that can be distributed to each of the adjustable power sources A to E. FIG.

At this time, for example, the output distribution unit 15 according to the merit order allocates 20 ARs to the control power source A with the lowest power generation cost. Further, the output distribution unit 15 according to the merit order allocates 20 ARs to the control power source B having the second lowest power generation cost.

Further, in FIG. 6B, it is assumed that the output allocable upper limit value changing unit 13 of FIG. 2 has determined, for example, 10 for each adjustable power source with respect to the allocation target value 40 of the output allocation.

At this time, for example, the output distribution unit 15 according to the merit order allocates 10 ARs to the control power source A with the lowest power generation cost. Further, the output distribution unit 15 according to the merit order allocates 10 ARs to the control power source B having the second lowest power generation cost. Further, the output allocation unit 15 according to the merit order allocates 10 ARs to the control power supply C having the third lowest power generation cost. Further, the output distribution unit 15 according to the merit order allocates 10 ARs to the control power source D having the fourth lowest power generation cost.

FIG. 7(a) is a diagram showing an example of a time-series output change in the output distribution for each controllability power supply based on the output distribution according to the merit order, and FIG. 7(b) is a diagram showing an example of a time-series output change in the output distribution for each controllability power supply based on the output distribution according to the merit order, with a lower upper limit value of the output allocatable output.

In FIG. 7A, after the output is distributed at t0, the output is distributed to the two adjustable power sources A and B. In FIG. At t1, the distribution target value 40 of the output distribution is reached.

In FIG. 7(b), after the output is distributed at t0, the output is distributed to the four adjustable power sources A, B, C, and D. At t2, the distribution target value 40 of the output distribution is reached.

The time required to reach the distribution target value of the output distribution becomes shorter as the output allocatable upper limit value becomes smaller, and as a result, t2 becomes smaller than t1.

As described above, according to the first embodiment described above, while allocating the control power to the control power supply according to the output change speed so that the system frequency falls within the allowable range, it is possible to allocate the control power to the control power power supply according to the merit order, and it is possible to reduce the cost while suppressing the frequency fluctuation according to the load fluctuation.

As a result, when the frequency fluctuation is large, the system frequency can be kept within the management target value by decreasing the output allocable upper limit value. On the other hand, when the frequency fluctuation is small, by increasing the output allocable upper limit value, it is possible to increase the ratio of output allocation to allocation destinations that greatly contribute to cost reduction, thereby reducing costs.

FIG. 8 is a block diagram of a functional configuration of the load frequency control device according to the second embodiment.

In FIG. 8, the load frequency control device 10 changes the input destination to the output allocable upper limit value changing unit 13 of the load frequency control device 10 in FIG. 2 from the frequency fluctuation Δf and the interconnection line power flow fluctuation ΔP to AR.

Also, the allocatable output upper limit value database DB2 of the load frequency control device 10 of FIG. 8 is changed from a function indicating the relationship between the frequency fluctuation and the allocable upper limit value to a function indicating the relationship between AR and the allocatable upper limit value.

First, an example of a method for manually creating an output allocable upper limit model will be described.

FIG. 9 is a diagram showing an example of the relationship with the allocatable upper limit value according to the AR referred to by the allocatable upper limit value changing unit of FIG. 8 .

In FIG. 9, the output allocatable upper limit value database DB2 of FIG. 8 holds the function of the output allocatable upper limit value. This output allocable upper limit is decreased as the AR fluctuation increases.

For example, when the AR fluctuation is 0 MW, the output allocable upper limit model sets the output allocable upper limit to the rated output. When the AR variation is greater than 0 MW and less than 200 MW, the output allocatable upper limit is set to a ratio greater than 0.0 and less than 1.0. When the AR fluctuation is 200 MW or more, the output allocatable upper limit is set to the output changeable width per command cycle.

Note that the allocatable output upper limit changing unit 13 may determine the allocatable upper limit based on the result of referring to the allocatable upper limit in FIG. 8, or may switch the allocatable upper limit when AR exceeds the threshold. Also, the AR threshold may be set in several stages.

Next, an example of a method for automatically creating an output allocable upper limit model will be described.

For example, past performance data (generator output, renewable energy output, frequency fluctuations, etc.) stored in the past data database and management target values such as frequency fluctuations (for example, Δf ± 0.1 Hz) are input, and by performing supply and demand analysis while changing the upper limit of possible output distribution as a parameter, the upper limit of possible output distribution that can be suppressed within the control target value for the original frequency fluctuation is calculated, and a regression model is created.

FIG. 10 shows an example of a method of referring to AR fluctuations when determining the output allocable upper limit value of FIG. 8 .

In FIG. 10, the output allocable upper limit value changing unit 13 in FIG. 8 monitors AR fluctuations. The output allocable upper limit changing unit 13 determines the output allocable upper limit based on the instantaneous value of the AR variation. At this time, the allocatable output upper limit changing unit 13 decreases the allocatable upper limit if the AR fluctuation is large, and increases the allocatable upper limit if the AR fluctuation is small.

For example, if the allocatable output upper limit changing unit 13 refers to the AR fluctuation at time t1 to determine the allocatable upper limit, since the AR fluctuation at time t1 is 100, the allocatable upper limit for the AR fluctuation of 100 is obtained from the allocatable upper limit value function of FIG. In the output allocatable upper limit value function of FIG. 9 , the allocatable upper limit value corresponding to an AR variation of 100 is 1.0, so the allocatable upper limit value changing unit 13 sets the allocatable upper limit value to 1.0 according to the merit order.

At this time, the output allocable upper limit changing unit 13 can update the output allocable upper limit at a period shorter than the load fluctuation time of several minutes to 20 minutes assumed in LFC. For example, the output allocable upper limit changing unit 13 can update the output allocable upper limit at intervals of 5 seconds.

The width of the time period P11 can be set based on the load fluctuation time of several minutes to 20 minutes assumed in LFC.

Moreover, as described above, in addition to the method of monitoring the AR based on the maximum value for the width of the time period, a method of monitoring the AR based on the standard deviation for the width of the time period may be used.

As described above, according to the second embodiment described above, even when the AR is used as an index, it is possible to allocate the controllability to the controllable power supply according to the merit order while allocating the controllability to the controllable power supply according to the output change rate so that the system frequency falls within the allowable range, and it is possible to reduce the cost while suppressing the frequency fluctuation according to the load fluctuation.

As a result, when the AR fluctuation is large, the system frequency can be kept within the management target value by decreasing the output allocable upper limit value. On the other hand, when the AR fluctuation is small, by increasing the output allocable upper limit value, it is possible to increase the ratio of output allocation to allocation destinations that greatly contribute to cost reduction, thereby reducing costs.

FIG. 11 is a block diagram of a functional configuration of the load frequency control device according to the third embodiment.

In FIG. 11, load frequency control device 10 changes the input destination to output allocable upper limit value changing unit 13 of load frequency control device 10 in FIG. 2 from frequency fluctuation Δf and interconnection line power flow fluctuation ΔP to renewable energy output fluctuation. Here, the renewable energy output fluctuation is assumed to be a value obtained by extracting a fluctuation component of several minutes to 20 minutes assumed in LFC.

Further, the allocatable output upper limit value database DB2 of the load frequency control device 10 of FIG. 11 is changed from a function indicating the relationship between the frequency fluctuation and the allocable upper limit value to a function indicating the relationship between the renewable energy output fluctuation and the allocatable upper limit value.

First, an example of a method for manually creating an output allocable upper limit model will be described.

FIG. 12 is a diagram showing an example of the relationship between the output allocable upper limit value and the output allocable upper limit value according to the renewable energy output referred to by the output allocable upper limit value changing unit in FIG.

In FIG. 12, the output allocatable upper limit value database DB2 of FIG. 11 holds an output allocatable upper limit value model. This output allocable upper limit is decreased as the renewable energy output fluctuation increases.

For example, the allocatable output upper limit model sets the allocatable upper limit to the rated output when the renewable energy output fluctuation is 0 MW. If the renewable energy output fluctuation is greater than 0 MW and less than 200 MW, the upper limit of allocatable output is set to a ratio greater than 0.0 and less than 1.0. As for the allocable output upper limit, when the renewable energy output fluctuation is 200 MW or more, the allocable output upper limit is set to the output changeable width per command cycle.

Note that the allocatable output upper limit changing unit 13 may determine the allocatable output upper limit based on the result of referring to the allocatable output upper limit in FIG. 12, or may switch the allocatable upper limit when the renewable energy output exceeds the threshold. Also, the threshold for renewable energy output may be set in several steps.

Next, an example of a method for automatically creating an output allocable upper limit model will be described.

For example, past performance data (generator output, renewable energy output, frequency fluctuations, etc.) stored in the past data database and management target values such as frequency fluctuations (for example, Δf ± 0.1 Hz) are input, and by performing supply and demand analysis while changing the upper limit of possible output distribution as a parameter, the upper limit of possible output distribution that can be suppressed within the control target value for the original frequency fluctuation is calculated, and a regression model is created.

FIG. 13 shows an example of a method of referring to renewable energy output fluctuations when determining the upper limit value of allocatable output in FIG. 11 .

In FIG. 13, the output allocable upper limit changing unit 13 of FIG. 11 monitors the renewable energy output fluctuation. The output allocable upper limit changing unit 13 determines the output allocable upper limit based on the instantaneous value of the renewable energy output fluctuation. At this time, the allocatable output upper limit changing unit 13 decreases the allocatable upper limit if the renewable energy output fluctuation is large, and increases the allocatable upper limit if the renewable energy output fluctuation is small.

For example, if the allocatable output upper limit changing unit 13 refers to the renewable energy output fluctuation at time t1 to determine the allocatable upper limit, the renewable energy output fluctuation at time t1 is 100. Therefore, the allocatable output upper limit corresponding to the renewable energy output fluctuation of 100 is obtained from the allocatable upper limit value function of FIG. In the output allocatable upper limit value function of FIG. 12, the allocatable upper limit value corresponding to the renewable energy output fluctuation of 100 is 1.0, so the allocatable upper limit value change unit 13 sets the allocatable upper limit value to 1.0 according to the merit order.

At this time, the output allocable upper limit changing unit 13 can update the output allocable upper limit at a period shorter than the load fluctuation time of several minutes to 20 minutes assumed in LFC. For example, the output allocable upper limit changing unit 13 can update the output allocable upper limit at intervals of 5 seconds.

The width of the time period P11 can be set based on the load fluctuation time of several minutes to 20 minutes assumed in LFC.

Moreover, as described above, in addition to the method of monitoring renewable energy output fluctuations based on the maximum value for the width of the time period, a method of monitoring renewable energy output fluctuations based on the standard deviation of the width of the time period may be used.

As described above, according to the above-described third embodiment, even when the renewable energy output is used as an index, it is possible to determine the upper limit of the possible output allocation between the adjustability according to the output change speed and the adjustability according to the merit order, and it is possible to reduce the cost while suppressing the frequency fluctuation according to the load fluctuation.

As a result, when the renewable energy output fluctuation is large, the grid frequency can be kept within the management target value by decreasing the output allocable upper limit value. On the other hand, when renewable energy output fluctuations are small, by increasing the output allocable upper limit, it is possible to increase the ratio of output allocation to allocation destinations that contribute significantly to cost reduction, thereby reducing costs.

FIG. 14 is a block diagram illustrating a functional configuration of a power system balancing group device according to a fourth embodiment. A balancing group is a function that aims to simultaneously achieve the same amount (matching the imbalance between actual power generation and actual demand, or the imbalance between planned and actual results) as a whole for multiple retailers or power generation companies that form a group, and to maximize profits in market transactions. When an imbalance occurs, the imbalance is eliminated by updating the plan such as output distribution.

A balancing group can be either a demand balancing group or a power generation balancing group.

In FIG. 14, the power system balancing group device 16 changes the input destination to the output allocable upper limit changing unit 13 of the load frequency control device 10 in FIG.

14, the power system balancing group device 16 changes the frequency fluctuation Δf, AR of the management target value input to the supply and demand analysis unit 12 of the load frequency control device 10 of FIG. 2 to supply and demand imbalance.

Also, the output allocable upper limit value database DB2 of the balancing group device 16 of FIG. 14 is changed from a function indicating the relationship between the supply and demand imbalance and the output allocable upper limit value to a function indicating the relationship between the supply and demand imbalance and the output allocable upper limit value.

As described above, according to the above-described fourth embodiment, even when the supply and demand imbalance is used as an index, it is possible to allocate the controllability to the controllability power supply according to the merit order while allocating the controllability to the controllability power supply according to the output change rate so that the system frequency falls within the allowable range, and it is possible to reduce the cost while suppressing the frequency fluctuation according to the load fluctuation.

As a result, when the supply-demand imbalance is large, the system frequency can be kept within the management target value by decreasing the output allocable upper limit value. On the other hand, when the imbalance between supply and demand is small, the ratio of output allocation to allocation destinations that greatly contribute to cost reduction can be increased by increasing the output allocable upper limit, thereby reducing costs.

In addition, the present invention is not limited to the above-described embodiments, and includes various modifications. For example, the above-described embodiments have been described in detail in order to explain the present invention in an easy-to-understand manner, and are not necessarily limited to those having all the described configurations. Also, part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Moreover, it is possible to add, delete, or replace a part of the configuration of each embodiment with another configuration.

Further, each of the above configurations, functions, processing units, processing means, and the like may be realized by hardware, for example, by designing them in an integrated circuit. The present invention can also be implemented by software program code that implements the functions of the embodiments. In this case, a computer is provided with a storage medium recording the program code, and a processor included in the computer reads the program code stored in the storage medium. In this case, the program code itself read from the storage medium implements the functions of the above-described embodiments, and the program code itself and the storage medium storing it constitute the present invention. Examples of storage media for supplying such program code include flexible disks, CD-ROMs, DVD-ROMs, hard disks, SSDs (Solid State Drives), optical disks, magneto-optical disks, CD-Rs, magnetic tapes, non-volatile memory cards, ROMs, and the like.

Also, the program code that implements the functions described in this embodiment can be implemented in a wide range of program or script languages such as assembler, C/C++, perl, Shell, PHP, and Java (registered trademark).

Furthermore, by distributing the program code of the software that implements the functions of the embodiments via a network, it may be stored in storage means such as a hard disk or memory of a computer or in a storage medium such as a CD-RW or CD-R, and a processor provided in the computer may read and execute the program code stored in the storage means or storage medium.

In the above-described embodiments, the control lines and information lines indicate those considered necessary for explanation, and not all control lines and information lines are necessarily indicated on the product. All configurations may be interconnected.

DB1 past data database, DB2 output allocable upper limit value database, DB3 output allocation command value database, 20 power system, 10 load frequency control device, 11 supply and demand adjustment device for power system, 12 supply and demand analysis unit, 13 output allocable upper limit value change unit, 14 AR calculation unit, 15 output distribution unit according to merit order, 16 balancing group device, 21 display unit, 22 input unit, 23 communication unit, 24 processor, 25 memory, 2 6 storage device, 27 bus, 300 communication network

Claims (6)

A supply and demand adjustment device for a power system used to determine output distribution to a control power supply that constitutes the power system,
an output allocable upper limit value database that stores a function indicating the relationship between the magnitude of the supply and demand imbalance and the output allocable upper limit value;
an output allocable upper limit value changing unit that refers to the function and changes the output allocable upper limit value to the adjustable power supply per one output allocation;
a past data database that stores past data of the output of the adjustable power supply and the output of the renewable energy;
a supply and demand analysis unit that performs a supply and demand analysis based on the past data of the output of the adjustable power supply and the output of the renewable energy stored in the past data database;
with
The supply and demand adjustment monitoring device for the electric power system creates the function based on the supply and demand analysis by the supply and demand analysis unit,
The output allocable upper limit value change unit determines the output allocable upper limit value of the output allocation according to economic efficiency as the supply and demand imbalance based on the magnitude of output fluctuation of renewable energy. A supply and demand adjustment device for a power system. In the supply and demand adjustment device for a power system according to claim 1,
The output allocable upper limit value changing unit determines the output allocable upper limit value of the output allocation according to economic efficiency as the supply and demand imbalance based on the frequency fluctuation of the power system. In the power system supply and demand adjustment device according to claim 1,
The output allocable upper limit value change unit determines the output allocable upper limit value of the output allocation according to economic efficiency as the supply and demand imbalance based on the magnitude of the regional demand amount. In a load frequency control device for a power system that determines the output distribution to the regulating power sources that make up the power system,
A supply and demand adjustment device for a power system according to claim 1;
an AR calculation unit that calculates an area requirement (AR) with the system frequency deviation and the power flow fluctuation of the interconnection line as inputs;
an output distribution unit according to the merit order for distributing the output according to the merit order based on the output allocable upper limit;
and an output distribution command value database storing output distribution command values for each of the control power sources. In a power system balancing group device that determines the output distribution to the regulating power sources that make up the power system,
A supply and demand adjustment device for a power system according to claim 1;
an output distribution unit according to the merit order for distributing the output according to the merit order based on the output allocable upper limit;
and an output distribution command value database storing output distribution command values for each of the control power sources. A supply and demand adjustment method by a supply and demand adjustment device of an electric power system used for determining output distribution to a control power supply that constitutes an electric power system,
Perform supply and demand analysis based on the past data of the output of the adjustable power supply and the output of renewable energy,
Based on the supply and demand analysis, create a function that indicates the relationship between the magnitude of the supply and demand imbalance and the upper limit of possible output allocation,
referring to the function to change the output allocable upper limit to the adjustable power supply per one output allocation ;
In changing the output allocable upper limit value, the output allocable upper limit value of the output allocation according to economic efficiency is determined as the supply and demand imbalance based on the magnitude of output fluctuation of renewable energy. A power system supply and demand adjustment method.

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