Real-time control method for participation of load-side distributed resources in primary frequency modulation of power system

Abstract

The invention belongs to the technical field of primary frequency modulation of a power system, and particularly relates to a real-time control method for participation of load-side distributed resources in primary frequency modulation of the power system. Comprising the steps of constructing a double-layer control structure in which distributed resources participate in primary frequency modulation of a power system; the distributed resources report own running state information to the virtual control unit according to a fixed time interval, the virtual control unit integrates running states, and an optimization model for the virtual control unit to participate in primary frequency modulation of the power system is established; and solving the optimization model of the virtual control unit participating in the primary frequency modulation of the power system to obtain the control method of the distributed resources participating in the primary frequency modulation of the power system. According to the method, the frequency modulation potential of the load side distributed resources is released, the frequency stability of the power system is improved, a theoretical basis can be provided for the distributed resources to participate in primary frequency modulation of the power system, meanwhile, powerful support is provided for development of the distributed resources, and the method is suitable for the load side distributed resources.

Description

Technical Field

[0001] The present invention belongs to the technical field of primary frequency regulation of power systems, and in particular relates to a real-time control method for load-side distributed resources participating in primary frequency regulation of power systems. Background Art

[0002] With the rapid development of science and technology, fossil energy, mainly oil and natural gas, has gradually dried up. Against this background, people have begun to explore the generation and utilization of new energy sources, which has led to the vigorous development of new energy sources, mainly wind power and photovoltaic power, and their share in the power generation resources of the power system has continued to increase. However, new energy sources are random, volatile and intermittent, which will have an impact on power stability. At the same time, due to the increase in the proportion of new energy sources, thermal power units, which are rotating elements, have been squeezed out, and new energy sources do not have rotation characteristics, which has caused a shortage of frequency stability resources in the power system, resulting in an increase in the risk of frequency accidents in the power system. Therefore, many scholars began to look for solutions to the above problems. With the improvement of scientific and technological levels, more and more scientific and technological products have appeared in residents' homes, including distributed resources that can interact with the power grid in both directions. They can participate in the primary frequency regulation of the power system as supplementary frequency stability resources to maintain the frequency stability of the power system.

[0003] The control of the participation of distributed resources in the primary frequency regulation of the power system refers to how the distributed resources execute the control commands issued after the power grid is disturbed. The distributed resources on the load side are characterized by huge quantity, scattered location and different characteristics. If the power system directly regulates them, it will greatly burden the operation of the power system and may cause unnecessary impact. However, if various distributed resources can be successfully regulated to participate in the frequency stabilization process of the power system, it will solve the problem of frequency safety and stability of the existing power system after disturbance.

[0004] The existing load-side distributed resources are characterized by large number, small capacity and dispersed locations, making them difficult to be directly controlled by the power grid dispatching center.

[0005] Therefore, utilizing distributed resources on the load side to participate in the primary frequency regulation of the power system will become a future development trend, and it is necessary to develop a real-time control method for the participation of distributed resources on the load side in the primary frequency regulation of the power system. Summary of the invention

[0006] In view of the shortcomings of the above-mentioned prior art, the present invention provides a real-time control method for load-side distributed resources participating in primary frequency regulation of the power system, which aims to achieve the invention purpose of making the best distributed resource control strategy for different disturbances.

[0007] The technical solution adopted by the present invention to achieve the above-mentioned purpose is:

[0008] The real-time control method for load-side distributed resources participating in primary frequency regulation of a power system comprises the following steps:

[0009] Construct a two-tier control structure for distributed resources to participate in primary frequency regulation of the power system;

[0010] Distributed resources report their operating status information to the virtual control unit at fixed time intervals. The virtual control unit integrates the operating status and establishes an optimization model for the virtual control unit to participate in the primary frequency regulation of the power system.

[0011] The optimization model of virtual control unit participating in primary frequency regulation of power system is solved, and the control method of distributed resources participating in primary frequency regulation of power system is obtained.

[0012] Furthermore, the two-layer control structure for constructing distributed resources to participate in the primary frequency regulation of the power system includes: distributed resources, a virtual control unit and a power system dispatching center;

[0013] Among them, the power system dispatching center is connected to the virtual control unit, which is the first layer; the virtual control unit is connected to the subordinate distributed resources, which is the second layer; the virtual control unit regularly reports the adjustable capacity to the power system dispatching center. During a dispatching cycle, the power system dispatching center combines the status information of the subordinate resources and calculates the control strategy sent to the virtual control unit according to the expected fault set. When a disturbance occurs, it is sent to the virtual control unit; the subordinate resource clusters of the virtual control unit regularly report their own operating status, and the virtual control unit formulates the control strategy for each resource cluster according to the reported information and task size;

[0014] The distributed resources under the virtual control unit include: energy storage devices, electric vehicles and demand response resources.

[0015] Furthermore, the optimization model of establishing a virtual control unit to participate in the primary frequency regulation of the power system is as follows: maxI VCU =I grid +I DER -C DER -C grid

[0016] The optimization model of virtual control unit participating in primary frequency regulation of power system takes the maximum income of virtual control unit as the optimization target;

[0017] The revenue of the virtual control unit includes two parts:

[0018] The income is the electricity purchase fee paid by the power system control center to the virtual control unit and the agency fee paid by the distributed resources to the virtual control unit; including: the agency fee I paid by the subordinate distributed resources DERand the power purchase fee paid by the power system dispatch center to the virtual control unit I grid ;

[0019] Expenses include the electricity purchase fee paid by the virtual control unit to each distributed resource and the penalty fee for the virtual control unit not completing the grid control center; including: the electricity purchase fee paid by the virtual control unit to its subordinate distributed resources C DER and the penalty fee C for the virtual control unit not completing the task sent by the power grid grid .

[0020] Furthermore, the benefits include:

[0021] (1) Electricity purchase fee provided by the power grid:

[0022] Among them, a i The cost coefficient for purchasing virtual control unit power for the power grid, N(t) is the total number of time periods in a dispatch day, P VCU,t is the power of the virtual control unit participating in the primary frequency regulation during period t, which is equal to the sum of the power of electric vehicles, battery energy storage devices and demand response resources participating in the primary frequency regulation during period t; N, M and H are the numbers of electric vehicles, battery energy storage devices and demand response resources participating in the primary frequency regulation respectively;

[0023] (2) Intermediary fees given by distributed resources: I DER , I DER =I EV +I BESS +I DR

[0024] Among them, I EV ,I BESS and I DR are the intermediation fees from EVs, battery storage devices and demand response resources to VCUs, respectively;

[0025] The expenses include:

[0026] (1) Penalty fees for failure to complete grid dispatching tasks:

[0027] in, is the part of the virtual control unit that completes the power grid control task, g i is the penalty cost coefficient, P t Control tasks issued by the power grid dispatching center;

[0028] (2) Electricity purchase fee for power purchased from distributed units: C DER , C DER =C EV +C BESS +CDR

[0029] Among them, C EV It represents the electricity purchase fee paid by the virtual control unit to the electric vehicle resources on a scheduling day, and the expression is in, is the power of electric vehicle i participating in frequency modulation in period t, c i Cost coefficient for electric vehicles to participate in primary frequency regulation; For the compensation of the virtual control unit to the electric vehicle, Battery compensation for electric vehicles participating in primary frequency regulation, u i,t is a binary variable. When it is 0, it means that the distributed resource i does not participate in a frequency modulation in period t. When it is 1, it means that the distributed resource i participates in a frequency modulation in period t. BESS The power purchase fee paid by the virtual control unit to the energy storage resource on a dispatch day is expressed as in, is the power of energy storage device i participating in frequency modulation in period t, d i is the cost coefficient of energy storage device participating in primary frequency regulation, To compensate the energy storage device for the virtual control unit, The battery compensation fee for the energy storage device participating in the primary frequency regulation, v i,t is a binary variable; C DR The electricity purchase fee paid by the virtual control unit for the demand response resource on a dispatch day is expressed as Among them, P DR,i,t is the power of demand response resource i participating in frequency regulation in period t, f i is the cost coefficient of demand response resources participating in primary frequency regulation, f i,t is a binary variable.

[0030] Furthermore, the electric vehicle, in actual operation, includes:

[0031] In actual operation, electric vehicles include:

[0032] (1) Charge and discharge power constraints,

[0033] (2) State of charge constraints, in, and are the minimum and maximum state of charge of the electric vehicle, is the rated battery capacity of the electric vehicle;

[0034] (3) Time coupling constraints, in is the maximum discharge power of the electric vehicle; it is assumed that the electric vehicle is charged at the rated power until it reaches the state of charge expected by the user outside the discharge state; E EV,i,t is the total battery capacity of the ith electric vehicle at the tth period, and are the minimum and maximum state of charge of the electric vehicle, is the rated battery capacity of the electric vehicle, η c1 and η d1 are the charging efficiency and discharging efficiency of electric vehicles, is the discharge power of electric vehicle i in period t, is the rated charging power of the electric vehicle;

[0035] The energy storage device, in actual operation, comprises:

[0036] (1) Charge and discharge power constraints:

[0037] (2) State of charge constraints, in, and They are the upper and lower limits of the state of charge of the battery energy storage in a frequency modulation. Rated battery capacity for battery energy storage;

[0038] (3) Time coupling constraints, in, and are the maximum discharge power and maximum charging power of battery energy storage respectively; E BESS,i,t is the total battery capacity of the i-th battery storage at the t-th time period, η c2 and η d2 are the charging efficiency and discharging efficiency of the energy storage device, respectively;

[0039] The demand response resources, in actual operation, include:

[0040] (1) Time response capacity constraint: P DR,i,min ≤P DR,i,t z i,t ≤P DR,i,max ; Among them, P DR,i,min and P DR,i,max are the maximum and minimum outputs of demand response resource i, respectively;

[0041] (2) Transfer times constraint: In order to satisfy the demand response resource users participating in the dispatch, the total number of transfers required in a day is A i ;

[0042] In actual operation, the formulation of the load-side distributed resource control strategy needs to meet the supply and demand requirements, that is, the system balance constraint.

[0043] Furthermore, the solving of the optimization model of the virtual control unit participating in the primary frequency regulation of the power system to obtain the control method for the distributed resources participating in the primary frequency regulation of the power system refers to solving the mathematical optimization model of the virtual control unit participating in the primary frequency regulation of the power system through optimization software to obtain the total income, penalty fee and benefit of the virtual control unit on a scheduling day, listing the comprehensive cost expression of the virtual control unit through the principles of market economics, and considering various equations and inequality constraints under actual operating conditions to obtain the control method for the distributed resources participating in the primary frequency regulation of the power system.

[0044] The real-time control device for the distributed resources on the load side to participate in the primary frequency regulation of the power system includes:

[0045] A building block for constructing a two-tier control structure for distributed resources to participate in primary frequency regulation of the power system;

[0046] The information reporting and establishment module is used for distributed resources to report their own operating status information to the virtual control unit at fixed time intervals. The virtual control unit integrates the operating status and establishes an optimization model for the virtual control unit to participate in the primary frequency regulation of the power system;

[0047] The solution module is used to solve the optimization model of the virtual control unit participating in the primary frequency regulation of the power system, and obtain the control method of the distributed resources participating in the primary frequency regulation of the power system.

[0048] Furthermore, the real-time control device for the participation of the load-side distributed resources in the primary frequency regulation of the power system is used to implement the steps of any one of the real-time control methods for the participation of the load-side distributed resources in the primary frequency regulation of the power system.

[0049] A computer device comprises a storage medium, a processor and a computer program stored on the storage medium and executable on the processor, wherein when the processor executes the computer program, the steps of any one of the methods for real-time control of the participation of distributed resources on the load side in primary frequency regulation of an electric power system are implemented.

[0050] A computer storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, the steps of any one of the methods for real-time control of load-side distributed resources participating in primary frequency regulation of an electric power system are implemented.

[0051] The present invention has the following beneficial effects and advantages:

[0052] The present invention intends to use virtual power plant technology to aggregate various types of distributed resources into virtual control units to participate in the primary frequency regulation of the power system. First, based on the constructed two-layer control structure of distributed resources participating in the primary frequency regulation of the power system, a control process for distributed resources to participate in the primary frequency regulation is established, and the rationality of distributed resources participating in the primary frequency regulation is realized. Secondly, appropriate distributed resources are selected to report information in real time to determine the operating status of various types of distributed resources. A mathematical model for the virtual control unit to participate in the primary frequency regulation of the power system is established. Compared with other models, this model takes into account three different distributed resources, comprehensively considers various equations and inequality constraints existing in the actual operating conditions, and correctly reflects the operating status of distributed resources. At the same time, in order to enable the virtual control unit to participate in the primary frequency regulation of the power system for a long time, the profit maximization of the virtual control unit is taken as the objective function. Finally, by solving the mathematical model, the control strategy for the participation of distributed resources in the primary frequency regulation of the power system can be obtained. This control method of the present invention, by establishing a real-time control model of the virtual control unit participating in the frequency, takes the operating status of the three resources into consideration, and takes the maximization of benefits as the goal, further releases the frequency regulation potential of the distributed resources on the load side and improves the frequency stability of the power system compared with the existing model, which can provide a theoretical basis for the participation of distributed resources in the primary frequency regulation of the power system, and also provides strong support for the development of distributed resources. The present invention is applicable to distributed resources on the load side. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0054] Figure 1 It is a schematic diagram of a double-layer structure in which distributed resources participate in primary frequency modulation according to the present invention;

[0055] Figure 2 This is a schematic diagram of the virtual control unit of the present invention;

[0056] Figure 3 It is a schematic diagram of the control plan of a single energy storage device 96-144 time period of the present invention;

[0057] Figure 4 It is a schematic diagram of the control plan for a single electric vehicle 96-144 period of the present invention;

[0058] Figure 5 It is a schematic diagram of the control plan for a single demand response resource 96-144 time period of the present invention. DETAILED DESCRIPTION

[0059] In order to more clearly understand the above-mentioned objectives, features and advantages of the present invention, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0060] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0061] Refer to the following Figure 1-Figure 5 The technical solutions of some embodiments of the present invention are described.

[0062] Example 1

[0063] The present invention provides an embodiment, which is a real-time control method for load-side distributed resources participating in primary frequency regulation of a power system. Figure 1 As shown, Figure 1 It is a schematic diagram of a double-layer structure in which distributed resources participate in primary frequency modulation according to the present invention.

[0064] The present invention provides a real-time control method for the participation of distributed resources on the load side in the primary frequency modulation of the power system. In view of the fact that the distributed resources on the load side are numerous, dispersed in location and small in capacity, and are difficult to be directly regulated by the power grid, the present invention aggregates multiple types of distributed resources together, and intends to use virtual power plant technology to build a virtual control unit to participate in the primary frequency modulation and coordinate the control of various types of distributed resources. On this basis, a two-layer control structure for the participation of distributed resources on the load side in the primary frequency modulation of the power system and a control method for the participation of distributed resources in the primary frequency modulation of the power system are proposed.

[0065] An optimization model for the virtual control unit to participate in primary frequency regulation is constructed. The objective function is to maximize the profit of the virtual control unit. By solving the optimization model, the real-time control strategy of each distributed resource can be obtained. That is, the control objective is to maximize the income of the virtual control unit, and the model is built according to the actual operation mechanism of the distributed resources. Based on the operating cost and various benefits of the virtual control unit, the annual total comprehensive cost expression of the battery swap station is listed according to the principles of market economics, and various equations and inequality constraints under actual operation are considered, so that the mathematical optimization model of the virtual control unit participating in the primary frequency regulation of the power system can be obtained.

[0066] The method of the present invention specifically comprises the following steps:

[0067] Step 1. Construct a two-layer control structure for distributed resources to participate in primary frequency regulation of the power system.

[0068] The double-layer control structure of the distributed resources participating in the primary frequency modulation of the power system of the present invention is composed of distributed resources, virtual control units and power system dispatching center. With the maximization of the total income of the virtual control center as the optimization goal, the distributed resources on the load side are aggregated into virtual control units, and a double-layer structure of distributed resources participating in the primary frequency modulation of the power system is constructed to realize the control of distributed resources. Among them, the power system dispatching center is connected to the virtual control unit, which is the first layer; the virtual control unit is connected to the subordinate distributed resources, which is the second layer. The connection between the various parts is as follows: the virtual control unit regularly reports the adjustable capacity to the power system dispatching center. The power system dispatching center combines the status information of the subordinate resources and calculates the control strategy sent to the virtual control unit according to the expected fault set within a dispatching cycle. When the disturbance occurs, it is sent to the virtual control unit. The subordinate resource clusters of the virtual control unit regularly report their own operating status, and the virtual control unit formulates the control strategy of each resource cluster according to the reported information and the task size. In the control structure, the virtual control unit plays the role of a hub. While receiving the signals of the distributed resources and the power system dispatching center, it also solves the optimization model to obtain the control plan of the distributed resources.

[0069] Step 2. The distributed resources report their operating status information to the virtual control unit at fixed time intervals. The virtual control unit integrates the operating status and establishes an optimization model for the virtual control unit to participate in the primary frequency regulation of the power system.

[0070] Before formulating a control plan, the distributed resources will report their operating status to the virtual control unit at a certain time interval, and the virtual control unit will integrate the operating status of each distributed resource. When a disturbance occurs, the power grid dispatch center sends a dispatch task to the virtual control center, and the virtual control center will combine the integrated operating status of each distributed resource to formulate the optimal distributed resource control strategy and complete the power grid control task.

[0071] During real-time control, the distributed resources under the virtual control unit will continuously sense their own operating status and report their own operating conditions to the virtual control unit at the same time interval. The virtual control unit will integrate the operating conditions of the distributed resources after receiving them each time, and make control plans in advance based on the regulation tasks that may be issued by the power grid.

[0072] Step 3. Solve the optimization model of the virtual control unit participating in the primary frequency regulation of the power system, and obtain the control method of the distributed resources participating in the primary frequency regulation of the power system.

[0073] When a power grid disturbance occurs, the power system dispatching center issues control tasks to the virtual control unit. The virtual control unit combines the operating status of each distributed resource and searches in the distributed resource control plan prepared in advance to match the best resource control plan. It then issues the control tasks of each distributed resource in the best way to complete the power grid control task.

[0074] The distributed resources under the virtual control unit include: energy storage devices, electric vehicles and demand response resources. The three types of distributed resources are more typical in people's lives. When the virtual control unit regulates various distributed resources, it is not only required that the control plan maximizes the benefits of the virtual control center, but also meets the actual operation constraints of each distributed resource. The virtual control unit exists as an intermediary in the process of distributed resources participating in the primary frequency regulation of the power system. It not only reduces the regulation pressure of the power system, but also reasonably controls each distributed resource.

[0075] Example 2

[0076] The present invention provides an embodiment, which is a real-time control method for load-side distributed resources participating in primary frequency regulation of a power system. The method comprises the following steps:

[0077] Step 1. Construct a two-layer control structure for distributed resources participating in primary frequency regulation of the power system as described in Example 1.

[0078] Step 2. Distributed resources report their operating status information to the virtual control unit at fixed time intervals. The virtual control unit integrates the operating status and establishes an optimization model for the virtual control unit to participate in the primary frequency regulation of the power system. This model comprehensively considers various equations and inequality constraints in actual operation, and at the same time, in order to enable distributed resources to participate in the primary frequency regulation of the power system for a long time, the profit maximization of the virtual control unit is taken as the objective function.

[0079] The present invention divides a scheduling day into 288 scheduling periods with a time interval of 5 minutes, formulates a control plan for the next 15 minutes of distributed resources every 5 minutes, and rolls over 288 times a day, and only executes the first 5-minute control plan among the 15 control plans each time.

[0080] Firstly, the real-time reporting information of each distributed resource is determined, and the operation process of distributed resources participating in the primary frequency regulation of the power system is formulated. Based on the established operation process, an optimization model of the virtual control unit participating in the primary frequency regulation of the power system is established.

[0081] In the established optimization model of virtual control units participating in primary frequency regulation of power system, in order to enable distributed resources to participate in primary frequency regulation of power system for a long time, the optimization model takes maximizing the income of virtual control units as the optimization goal.

[0082] like Figure 2 As shown, Figure 2 This is a schematic diagram of the income of the virtual control unit of the present invention. The income of the virtual control unit includes two parts. One part is the income, which is the electricity purchase fee paid by the power system control center to the virtual control unit and the intermediary fee paid by the distributed resources to the virtual control unit; the second part is the expenditure, which is the electricity purchase fee paid by the virtual control unit to each distributed resource and the penalty fee for the virtual control unit not completing the power grid control center.

[0083] The expression of the objective function is: maxI VCU =I grid +I DER -C DER -C grid .

[0084] The income includes: the agency fees submitted by subordinate distributed resources I DER and the power purchase fee paid by the power system dispatch center to the virtual control unit grid .

[0085] Expenses include: The electricity purchase fee paid by the virtual control unit to its subordinate distributed resources C DER and the penalty fee C for the virtual control unit not completing the task sent by the power grid grid .

[0086] Step 3. Solve the optimization model of the virtual control unit participating in the primary frequency regulation of the power system, and obtain the control method of the distributed resources participating in the primary frequency regulation of the power system.

[0087] When a power grid disturbance occurs, the power system dispatching center issues control tasks to the virtual control unit. The virtual control unit formulates the optimal distributed resource control strategy based on the operating status of each distributed resource to complete the power grid control task.

[0088] According to the revenue and expenditure provisions of the virtual control unit, the comprehensive cost expression of the virtual control unit is listed through the principles of market economics, and considering various equations and inequality constraints under actual operation, a mathematical optimization model for distributed resources participating in the primary frequency regulation of the power system can be obtained.

[0089] In the present invention, three typical distributed resources are selected to participate in the primary frequency regulation of the power system. They are not only common on the load side, but also play a greater role in people's production and life. They are electric vehicles, energy storage devices and demand response resources.

[0090] The income of the virtual control unit consists of two parts. The first part is the electricity purchase fee given by the power grid. grid , The second part is the agency fee given by the distributed resources IDER , I DER =I EV +I BESS +I DR .a i The cost coefficient for purchasing virtual control unit power for the power grid, N(t) is the total number of time periods in a dispatch day. VCU,t is the power of the virtual control unit participating in the primary frequency regulation during period t, which is equal to the sum of the power of electric vehicles, battery energy storage devices and demand response resources participating in the primary frequency regulation during period t. EV ,I BESS and I DR are the intermediary fees of electric vehicles, battery energy storage devices and demand response resources to the virtual control unit. N, M and H are the number of electric vehicles, battery energy storage devices and demand response resources participating in primary frequency regulation.

[0091] At the same time, the expenditure is divided into two parts. The first part is the penalty fee C for not completing the grid dispatching task. grid , The second part is the electricity purchase fee C for purchasing power from distributed units. DER , C DER =C EV +C BESS +C DR . is the part of the virtual control unit that completes the power grid control task, g i is the penalty cost coefficient, P t It is a control task issued by the power grid dispatching center.

[0092] C EV It represents the electricity purchase fee paid by the virtual control unit to the electric vehicle resources on a scheduling day. Its expression is: in is the power of electric vehicle i participating in frequency modulation in period t, c i This is the cost coefficient for electric vehicles to participate in frequency regulation. Every time an electric vehicle is charged and discharged, its battery will be damaged, so it needs to be compensated. For the compensation of the virtual control unit to the electric vehicle, Battery compensation for electric vehicles participating in primary frequency regulation, u i,t is a binary variable. When it is 0, it means that the distributed resource i does not participate in a frequency modulation in period t. When it is 1, it means that the distributed resource i participates in a frequency modulation in period t.

[0093] C BESS It represents the electricity purchase fee paid by the virtual control unit to the energy storage resource on a dispatch day. Its expression is: in is the power of energy storage device i participating in frequency modulation in period t, d i This is the cost coefficient for the energy storage device to participate in a frequency regulation. Each time the energy storage device is charged and discharged, its battery will be damaged, so it needs to be compensated. To compensate the energy storage device for the virtual control unit, The battery compensation fee for the energy storage device participating in the primary frequency regulation, v i,t is a binary variable.

[0094] C DR The electricity purchase fee paid by the virtual control unit for the demand response resource on a dispatch day is expressed as P DR,i,t is the power of demand response resource i participating in frequency regulation in period t, f i is the cost coefficient of demand response resources participating in primary frequency regulation, f i,t is a binary variable.

[0095] In order to maximize the benefits of the virtual control unit, when the power grid control center sends the dispatching task to the virtual control unit, the virtual control unit compares the required dispatching capacity with the dispatchable capacity of each distributed unit, and gives priority to the distributed resources with low dispatching capacity cost.

[0096] During actual operation, the control tasks issued by the virtual control center need to be combined with the operating status of distributed resources, that is, there are constraints on the operating status of distributed resources.

[0097] In actual operation, electric vehicles include:

[0098] (1) Charge and discharge power constraints,

[0099] (2) State of charge constraints, in, and are the minimum and maximum state of charge of the electric vehicle, is the rated battery capacity of the electric vehicle.

[0100] (3) Time coupling constraints, in is the maximum discharge power of the electric vehicle. In the present invention, it is assumed that the electric vehicle is charged at the rated power until the state of charge desired by the user is reached. EV,i,t is the total battery capacity of the ith electric vehicle at the tth period, and are the minimum and maximum state of charge of the electric vehicle, is the rated battery capacity of the electric vehicle. η c1 and ηd1 are the charging efficiency and discharging efficiency of electric vehicles, is the discharge power of electric vehicle i in period t, is the rated charging power of the electric vehicle.

[0101] The method of the present invention formulates a control plan for distributed resources based on the maximum income of the virtual control unit; under the control mode of the distributed resource real-time control method, the number of power batteries required to be configured in the electric vehicle battery swap station can be obtained by solving the objective function described by the income of the virtual control unit and the mathematical optimization model composed of the constraints of the distributed resource real-time control method.

[0102] In actual operation, energy storage devices include:

[0103] (1) Charge and discharge power constraints:

[0104] (2) State of charge constraints, in, and They are the upper and lower limits of the state of charge of the battery energy storage in a frequency modulation. The rated battery capacity for battery energy storage.

[0105] (3) Time coupling constraints, in, and E are the maximum discharge power and maximum charging power of battery energy storage respectively. BESS,i,t is the total battery capacity of the i-th battery storage at the t-th time period, η c2 and η d2 are the charging efficiency and discharging efficiency of the energy storage device respectively.

[0106] Demand response resources in actual operation include:

[0107] (1) Time response capacity constraint: P DR,i,min ≤P DR,i,t z i,t ≤P DR,i,max ; Among them, P DR,i,min and P DR,i,max are the maximum and minimum outputs of demand response resource i respectively.

[0108] (2) Transfer times constraint: In order to satisfy the demand response resource users participating in the dispatch, the total number of transfers required in a day is A i .

[0109] In actual operation, the formulation of the load-side distributed resource control strategy needs to meet the supply and demand requirements, that is, the system balance constraint.

[0110] like Figure 3 , Figure 4 and Figure 5 As shown, Figure 3 This is a schematic diagram of the control plan for a single energy storage device 96-144 period of the present invention. Figure 4 This is a schematic diagram of the control plan for a single electric vehicle during the 96-144 period of the present invention. Figure 5 This is a schematic diagram of the control plan of a single demand response resource 96-144 period of the present invention. It can be seen that around the 96 period, the power grid is disturbed, and the three load-side distributed resources are all in working state, jointly completing the control task issued by the power grid.

[0111] In order to be practical, the present invention sets that there are 20 electric vehicles from 8 pm to 8 am; there are 5 electric vehicles from 8 am to 8 pm, the charging and discharging efficiency of electric vehicles is 95%, the minimum and maximum charge states are 0.1 and 0.9, and the unit electricity purchase cost is different for different electric vehicles. The number of battery energy storage and demand response resources on a scheduling day is 5 and 2 respectively. The energy storage device has a charging and discharging efficiency of 95%, and the minimum and maximum charge states are 0.45 and 0.55. The unit electricity purchase cost of different energy storage devices is different. The number of times that demand response resources can be transferred from 8 pm to 8 am is less than 50, and the number of times that can be transferred from 8 am to 8 pm is a decimal of 76, and the maximum and minimum outputs of different demand response resources are different.

[0112] By solving the mathematical optimization model of the virtual control unit participating in the primary frequency regulation of the power system through CPLEX optimization software, it can be obtained that the total income of the virtual control unit on a dispatching day is 63579.04 yuan, the penalty fee is 9573.9 yuan, and the profit is 54005.14 yuan.

[0113] Example 3

[0114] The present invention further provides an embodiment, which is a real-time control device for load-side distributed resources participating in primary frequency regulation of a power system, comprising:

[0115] A building block for constructing a two-tier control structure for distributed resources to participate in primary frequency regulation of the power system;

[0116] The information reporting and establishment module is used for distributed resources to report their own operating status information to the virtual control unit at fixed time intervals. The virtual control unit integrates the operating status and establishes an optimization model for the virtual control unit to participate in the primary frequency regulation of the power system;

[0117] The solution module is used to solve the optimization model of the virtual control unit participating in the primary frequency regulation of the power system, and obtain the control method of the distributed resources participating in the primary frequency regulation of the power system.

[0118] The real-time control device for the participation of load-side distributed resources in the primary frequency regulation of the power system described in this embodiment is used to implement the steps of the real-time control method for the participation of load-side distributed resources in the primary frequency regulation of the power system as described in Examples 1-2.

[0119] Example 4

[0120] Based on the same inventive concept, an embodiment of the present invention further provides a computer device, including a storage medium, a processor, and a computer program stored on the storage medium and executable on the processor. When the processor executes the computer program, the steps of any of the methods for real-time control of load-side distributed resources participating in primary frequency regulation of a power system described in Embodiment 1 or 2 are implemented.

[0121] Example 5

[0122] Based on the same inventive concept, an embodiment of the present invention also provides a computer storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the real-time control method for load-side distributed resources participating in the primary frequency regulation of the power system described in any one of Embodiments 1 or 2 are implemented.

[0123] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0124] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0125] These computer program instructions may also be stored in a computer readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0126] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0127] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A real-time control method for load-side distributed resources participating in primary frequency regulation of a power system, characterized by: The following steps are involved: Construct a two-tier control structure for distributed resources to participate in primary frequency regulation of the power system; Distributed resources report their operating status information to the virtual control unit at fixed time intervals. The virtual control unit integrates the operating status and establishes an optimization model for the virtual control unit to participate in the primary frequency regulation of the power system. The optimization model of virtual control unit participating in primary frequency regulation of power system is solved, and the control method of distributed resources participating in primary frequency regulation of power system is obtained.

2. The real-time control method for load-side distributed resources participating in primary frequency modulation of a power system according to claim 1 is characterized in that: The dual-layer control structure for constructing distributed resources to participate in the primary frequency regulation of the power system includes: distributed resources, a virtual control unit and a power system dispatching center; Among them, the power system dispatching center is connected to the virtual control unit, which is the first layer; the virtual control unit is connected to the subordinate distributed resources, which is the second layer; the virtual control unit regularly reports the adjustable capacity to the power system dispatching center. During a dispatching cycle, the power system dispatching center combines the status information of the subordinate resources and calculates the control strategy sent to the virtual control unit according to the expected fault set. When a disturbance occurs, it is sent to the virtual control unit; the subordinate resource clusters of the virtual control unit regularly report their own operating status, and the virtual control unit formulates the control strategy for each resource cluster according to the reported information and task size; The distributed resources under the virtual control unit include: energy storage devices, electric vehicles and demand response resources.

3. The real-time control method for load-side distributed resources participating in primary frequency modulation of a power system according to claim 1 is characterized by: The optimization model of establishing a virtual control unit to participate in the primary frequency regulation of the power system is as follows: VCU =I grid +I DER -C DER -C grid The optimization model of virtual control unit participating in primary frequency regulation of power system takes the maximum income of virtual control unit as the optimization target; The revenue of the virtual control unit includes two parts: The income is the electricity purchase fee paid by the power system control center to the virtual control unit and the agency fee paid by the distributed resources to the virtual control unit; including: the agency fee I paid by the subordinate distributed resources DER and the power purchase fee paid by the power system dispatch center to the virtual control unit I grid ; Expenses include the electricity purchase fee paid by the virtual control unit to each distributed resource and the penalty fee for the virtual control unit not completing the grid control center; including: the electricity purchase fee paid by the virtual control unit to its subordinate distributed resources C DER and the penalty fee C for the virtual control unit not completing the task sent by the power grid grid .

4. The real-time control method for load-side distributed resources participating in primary frequency modulation of a power system according to claim 3 is characterized by: The benefits include: (1) Electricity purchase fee from the power grid: I grid , Among them, a i The cost coefficient for purchasing virtual control unit power for the power grid, N(t) is the total number of time periods in a dispatch day, P VCU,t is the power of the virtual control unit participating in the primary frequency regulation during period t, which is equal to the sum of the power of electric vehicles, battery energy storage devices and demand response resources participating in the primary frequency regulation during period t; N, M and H are the numbers of electric vehicles, battery energy storage devices and demand response resources participating in the primary frequency regulation respectively; (2) Intermediary fees given by distributed resources: I DER , I DER =I EV +I BESS +I DR Among them, I EV ,I BESS and I DR are the intermediation fees from EVs, battery storage devices and demand response resources to VCUs, respectively; The expenses include: (1) Penalty fee for failure to complete grid dispatching tasks: C grid , in, is the part of the virtual control unit that completes the power grid control task, g i is the penalty cost coefficient, P t Control tasks issued by the power grid dispatching center; (2) Electricity purchase fee for power purchased from distributed units: C DER , C DER =C EV +C BESS +C DR Among them, C EV It represents the electricity purchase fee paid by the virtual control unit to the electric vehicle resources on a scheduling day, and the expression is in, is the power of electric vehicle i participating in frequency modulation in period t, c i Cost coefficient for electric vehicles to participate in primary frequency regulation; For the compensation of the virtual control unit to the electric vehicle, Battery compensation for electric vehicles participating in primary frequency regulation, u i,t is a binary variable. When it is 0, it means that the distributed resource i does not participate in a frequency modulation in period t. When it is 1, it means that the distributed resource i participates in a frequency modulation in period t. BESS The power purchase fee paid by the virtual control unit to the energy storage resource on a dispatch day is expressed as in, is the power of energy storage device i participating in frequency modulation in period t, d i is the cost coefficient of energy storage device participating in primary frequency regulation, To compensate the energy storage device for the virtual control unit, The battery compensation fee for the energy storage device participating in the primary frequency regulation, v i,t is a binary variable; C DR The electricity purchase fee paid by the virtual control unit for the demand response resource on a dispatch day is expressed as Among them, P DR,i,t is the power of demand response resource i participating in frequency regulation in period t, f i is the cost coefficient of demand response resources participating in primary frequency regulation, f i,t is a binary variable.

5. The real-time control method for load-side distributed resources participating in primary frequency modulation of a power system according to claim 2 is characterized by: The electric vehicle, in actual operation, comprises: In actual operation, electric vehicles include: (1) Charge and discharge power constraints, (2) State of charge constraints, in, and are the minimum and maximum state of charge of the electric vehicle, is the rated battery capacity of the electric vehicle; (3) Time coupling constraints, in is the maximum discharge power of the electric vehicle; it is assumed that the electric vehicle is charged at the rated power until it reaches the state of charge expected by the user outside the discharge state; E EV,i,t is the total battery capacity of the ith electric vehicle at the tth period, and are the minimum and maximum state of charge of the electric vehicle, is the rated battery capacity of the electric vehicle, η c1 and η d1 are the charging efficiency and discharging efficiency of electric vehicles, is the discharge power of electric vehicle i in period t, is the rated charging power of the electric vehicle; The energy storage device, in actual operation, comprises: (1) Charge and discharge power constraints: (2) State of charge constraints, in, and They are the upper and lower limits of the state of charge of the battery energy storage in a frequency modulation. Rated battery capacity for battery energy storage; (3) Time coupling constraints, in, and are the maximum discharge power and maximum charging power of battery energy storage respectively; E BESS,i,t is the total battery capacity of the i-th battery storage at the t-th time period, η c2 and η d2 are the charging efficiency and discharging efficiency of the energy storage device, respectively; The demand response resources, in actual operation, include: (1) Time response capacity constraint: P DR,i,min ≤P DR,i,t z i,t ≤P DR,i,max ; Among them, P DR,i,min and P DR,i,max are the maximum and minimum outputs of demand response resource i, respectively; (2) Transfer times constraint: In order to satisfy the demand response resource users participating in the dispatch, the total number of transfers required in a day is A i ; In actual operation, the formulation of the load-side distributed resource control strategy needs to meet the supply and demand requirements, that is, the system balance constraint.

6. The real-time control method for load-side distributed resources participating in primary frequency modulation of a power system according to claim 1 is characterized by: The described solution of the optimization model of the virtual control unit participating in the primary frequency regulation of the power system to obtain the control method for the distributed resources participating in the primary frequency regulation of the power system refers to solving the mathematical optimization model of the virtual control unit participating in the primary frequency regulation of the power system through optimization software to obtain the total income, penalty fee and benefit of the virtual control unit on a scheduling day, listing the comprehensive cost expression of the virtual control unit through the principles of market economics, and considering various equations and inequality constraints under actual operating conditions to obtain the control method for the distributed resources participating in the primary frequency regulation of the power system.

7. A real-time control device for load-side distributed resources participating in primary frequency regulation of a power system, characterized by: A building block for constructing a two-tier control structure for distributed resources to participate in primary frequency regulation of the power system; The information reporting and establishment module is used for distributed resources to report their own operating status information to the virtual control unit at fixed time intervals. The virtual control unit integrates the operating status and establishes an optimization model for the virtual control unit to participate in the primary frequency regulation of the power system; The solution module is used to solve the optimization model of the virtual control unit participating in the primary frequency regulation of the power system, and obtain the control method of the distributed resources participating in the primary frequency regulation of the power system.

8. The real-time control device for load-side distributed resources participating in primary frequency modulation of a power system according to claim 1, characterized in that: The real-time control device for the participation of load-side distributed resources in the primary frequency regulation of the power system is used to implement the steps of the real-time control method for the participation of load-side distributed resources in the primary frequency regulation of the power system as described in any one of claims 1-6.

9. A computer device comprising a storage medium, a processor, and a computer program stored in the storage medium and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the real-time control method for load-side distributed resources participating in the primary frequency regulation of the power system as described in any one of claims 1 to 6 are implemented.

10. A computer storage medium, characterized in that: The computer storage medium stores a computer program, which, when executed by a processor, implements the steps of the real-time control method for load-side distributed resources participating in primary frequency regulation of a power system as described in any one of claims 1 to 6.

Images