Multi-type reactive power resource scheduling control method for power grid containing high-proportion new energy

Abstract

The invention discloses a multi-type reactive power resource scheduling control method for a power grid containing high-proportion new energy. The multi-type reactive power resource scheduling control method for the power grid containing the high-proportion new energy comprises the following steps: acquiring operation characteristic data of a reactive power device, and determining a working sequence of a reactive power compensation device according to the operation characteristic data of the reactive power device; based on the performance index of the reactive power compensation device, combining the operation characteristic data of the reactive power device and the working order of the reactive power compensation device to construct a reactive power resource scheduling control model; and solving the reactive power resource scheduling control model by adopting an improved genetic optimization algorithm, and outputting a static reactive power compensation device switching instruction. According to the multi-type reactive power resource scheduling control method for the power grid containing the high-proportion new energy, the effect of preventing voltage instability is achieved, and the problem that in the prior art, a single reactive power compensation device cannot guarantee the voltage stability is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of power system voltage regulation, and in particular to a multi-type reactive resource dispatching and control method for a power grid containing a high proportion of new energy. Background Art

[0002] In the context of the global promotion of carbon peak and carbon neutrality goals, the country is actively promoting the development and application of renewable energy such as photovoltaic and wind power to replace traditional coal-fired and gas-fired power generation. However, the grid-connected operation of a high proportion of new energy has put forward higher requirements for the planning and operation of modern power systems. Specifically, in the sending-end power grid where new energy is densely connected, output fluctuations in a short period of time may cause voltage instability, especially when the key grid-connected nodes and transmission channels are not reasonably equipped with reactive power compensation devices, the safety and stability of the power grid are seriously threatened.

[0003] In the existing technology, although the static reactive power compensation device has a low configuration cost and a large compensation capacity, its response speed is slow; while the dynamic reactive power compensation device has a fast response and excellent regulation performance. It is difficult to fully cope with the complex challenges brought by the high proportion of new energy grid connection by using any single reactive power compensation device. Therefore, there is an urgent need for a dispatching control strategy that comprehensively utilizes multiple reactive power compensation resources to ensure the voltage stability of the power grid under steady-state and dynamic conditions and ensure the effective grid connection of a high proportion of new energy.

[0004] In summary, the present invention aims to solve the problem of voltage stability in power grids with a high proportion of renewable energy and propose a multi-type reactive resource dispatching and control strategy to optimize power grid operation and improve the grid connection efficiency of renewable energy stations. Summary of the invention

[0005] In order to overcome the above-mentioned defects of the prior art, an embodiment of the present invention provides a multi-type reactive resource scheduling and control method for a power grid containing a high proportion of new energy sources, which optimizes the configuration and adjustment of static and dynamic reactive compensation devices to solve the problem that a single reactive compensation device cannot guarantee voltage stability.

[0006] To achieve the above object, the present invention provides the following technical solutions: A multi-type reactive resource dispatching and control method for a power grid containing a high proportion of new energy sources comprises the following steps: obtaining reactive device operating characteristic data, determining the working order of reactive compensation devices according to the reactive device operating characteristic data, wherein the reactive device operating characteristic data comprises static reactive compensation device operating characteristics and dynamic reactive compensation device operating characteristics; constructing a reactive resource dispatching and control model based on performance indicators of reactive compensation devices and in combination with the reactive device operating characteristic data and the working order of reactive compensation devices; solving the reactive resource dispatching and control model by adopting an improved genetic optimization algorithm, and outputting switching instructions for static reactive compensation devices.

[0007] In a preferred embodiment, the working order of the reactive compensation device is determined based on the operating characteristic data of the reactive device, specifically: the static reactive compensation device is preset to perform a switching operation once every preset time period; when the static reactive compensation device cannot meet the required reactive compensation capacity, the dynamic reactive compensation device will provide a one-time reactive compensation based on the reactive compensation capacity and the predetermined time interval.

[0008] In a preferred embodiment, the reactive resource scheduling control model includes establishing a reactive compensation device objective function based on the performance index of the reactive compensation device, and constraints of the reactive compensation device objective function.

[0009] In a preferred embodiment, the constraint conditions of the objective function of the reactive power compensation device include power grid safe operation constraint, reactive power compensation device action constraint, and adjustment number constraint.

[0010] In a preferred embodiment, the switching instruction of the static reactive power compensation device includes a switching state and operating parameters, specifically: the switching state includes a startup instruction and a removal instruction, the startup instruction instructs the static reactive power compensation device to be connected to the power grid to increase reactive power, and the removal instruction instructs the static reactive power compensation device to be removed from the power grid to reduce reactive power; the operating parameters include reactive power value, operating time and priority, the reactive power value display specifically indicates the reactive power value to be switched, the operating time indicates the effective time period of the instruction, that is, the duration, and the priority refers to the order of priority execution when multiple switching instructions exist at the same time.

[0011] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages: 1. A multi-type reactive resource dispatching and control method for a power grid with a high proportion of new energy is adopted to ensure that the power grid can cope with the fluctuation of new energy output in a short period of time, thereby preventing voltage instability and effectively solving the problem in the prior art that a single reactive compensation device cannot guarantee voltage stability.

[0012] 2. By combining static and dynamic reactive power compensation devices, the required reactive power can be quickly provided when the power grid fails or the load changes, thereby effectively avoiding voltage instability.

[0013] 3. By using an improved genetic algorithm to solve the model, the approximate optimal solution for reactive resource scheduling can be effectively found, thereby ensuring reactive resource scheduling while meeting the requirements of economy and safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1A flow chart of a method for dispatching and controlling multiple types of reactive resources in a power grid with a high proportion of new energy provided in an embodiment of the present application; Figure 2 A flow chart of the solution of an improved genetic optimization algorithm for a power grid containing a high proportion of new energy provided in an embodiment of the present application. DETAILED DESCRIPTION

[0015] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0016] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "include..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0017] Embodiment 1, Figure 1 The present invention provides a multi-type reactive resource dispatching control method for a power grid containing a high proportion of new energy, comprising the following steps: Acquire reactive device operation characteristic data, and determine the working order of the reactive compensation device according to the reactive device operation characteristic data, wherein the reactive device operation characteristic data includes static reactive compensation device operation characteristics and dynamic reactive compensation device operation characteristics; Based on the performance index of the reactive compensation device, in combination with the reactive device operation characteristic data and the working order of the reactive compensation device, a reactive resource scheduling control model is constructed, wherein the reactive resource scheduling control model includes establishing a reactive compensation device objective function based on the performance index of the reactive compensation device, and constraint conditions of the reactive compensation device objective function; An improved genetic optimization algorithm is used to solve the reactive resource dispatching control model and output switching instructions for a static reactive power compensation device.

[0018] Considering the response characteristics of different reactive resources, the working order of the reactive compensation device is determined according to the reactive device operation characteristic data, specifically: The static reactive power compensation device is preset to perform a switching operation once every preset time period; When the static reactive power compensation device cannot meet the required reactive power compensation capacity, the dynamic reactive power compensation device will provide a one-time reactive power compensation according to the reactive power compensation capacity and a predetermined time interval.

[0019] It should be noted that in actual operation, after the static reactive power compensation device is put into use and the capacity is determined, when the reactive power compensation capacity exceeds the rated reactive power compensation capacity, the part is provided by the dynamic reactive power compensation device. In addition, due to the fluctuation of new energy output and load forecasting errors, the real-time response operating characteristics of the dynamic reactive power compensation device are used to perform reactive power compensation according to the node voltage changes.

[0020] It should be noted that switching on and off refers to the process of activating and deactivating the static VAR compensation device. Switching on means activating the static VAR compensation device so that it starts to provide reactive power to support the voltage regulation of the power grid. Switching on means deactivating the static VAR compensation device and stopping its provision of reactive power.

[0021] The performance indicators of the reactive power compensation device include economic indicators of the adjustment cost of the static reactive power compensation device and safety indicators of the dynamic reactive power compensation device for the dynamic support of the grid voltage.

[0022] Based on the economic index of the static reactive power compensation device regulation cost and the security index of the dynamic reactive power compensation device for the dynamic support of the grid voltage as the reactive power compensation device objective function, the specific calculation formula is as follows:

[0023] Where: α and β are weight coefficients of the objective function of the reactive power compensation device, E represents the economic index of the adjustment cost of the static reactive power compensation device, S represents the security index of the dynamic reactive power compensation device for the dynamic support of the grid voltage, is the decision variable of the reactive resource dispatch control model, is the adjustment times of the ith static reactive compensation device, C is the unit adjustment cost of the static reactive compensation device, is the reactive power output value of the ith dynamic reactive power compensation device, is the reactive capacity of the i-th dynamic reactive compensation device.

[0024] It should be noted that the safety index of the dynamic reactive power compensation device for the dynamic support of the grid voltage represents the relative reactive power output of the dynamic reactive power compensation device in the next four hours; it can reflect the reactive power margin of the dynamic reactive power compensation device. The smaller the relative reactive power output, the larger the margin of the dynamic reactive power compensation device, which can provide more reactive power emergency support under grid fault conditions.

[0025] The new energy output forecast results, load forecast results and power grid operation plan are obtained from the new energy station output forecast system, regional load forecast system and substation data acquisition and monitoring control system respectively, and the reactive resource dispatching control strategy framework is designed based on the new energy output forecast results, load forecast results and power grid operation plan.

[0026] The constraint conditions of the objective function of the reactive power compensation device include power grid safe operation constraint, reactive power compensation device action constraint, and adjustment number constraint.

[0027] The power grid safe operation constraints include node voltage constraints and system power flow constraints.

[0028] The node voltage constraint is expressed as follows:

[0029] Where: is the voltage of the ith node.

[0030] The system power flow constraint is expressed as follows:

[0031] Where: is the set of lines with the grid operation node k as the terminal, is the set of lines with the grid operation node k as the starting point, i as the input node, j as the output node, M as the set of AC nodes, is the voltage of the ith node, is the active power on line ik collected based on the designed reactive resource scheduling control strategy framework, is the reactive power on line ik collected based on the designed reactive resource dispatch control strategy framework, is the equivalent resistance of line ik, is the equivalent reactance of line ik, The active power injected into the grid operation node k, It is the reactive power injected by the grid operation node k collected based on the designed reactive resource scheduling control strategy framework.

[0032] It should be noted that in terms of node voltage constraints, each node in the regional power grid where wind farms are densely connected needs to meet the voltage stability operation requirements.

[0033] It should be noted that in terms of system flow constraints, based on the grid operation plan in the designed reactive resource dispatching and control strategy framework, combined with the new energy output forecast result data, load forecast result data and other data obtained in the reactive resource dispatching and control strategy framework, the system flow constraints need to meet the active and reactive balance operating conditions of each node.

[0034] The reactive power compensation device action constraints include reactive power compensation device output constraints and static reactive power compensation device adjustment time interval constraints.

[0035] Among them, the output constraint of the reactive power compensation device is expressed as follows:

[0036] Where: is the reactive power output value of the i-th static reactive power compensation device, is the reactive power output value of the ith dynamic reactive power compensation device, is the minimum value of reactive power output of the ith static reactive power compensation device, is the maximum reactive power output of the ith static reactive power compensation device, is the minimum value of reactive power output of the ith dynamic reactive power compensation device, is the maximum value of the reactive power output of the ith dynamic reactive power compensation device.

[0037] The static reactive power compensation device adjusts the time interval constraint, and the formula is expressed as follows:

[0038] Where: is the jth action time of the static reactive power compensation device, It is the minimum action time interval requirement for static reactive power compensation device.

[0039] It should be noted that in terms of the constraints on the adjustment time interval of the static reactive power compensation device, the switching times of the static reactive power compensation device should not be too frequent, and the time interval of the switching action needs to be clearly constrained.

[0040] The constraint on the number of adjustments is expressed in the following formula:

[0041] Where: is the decision variable of the reactive resource dispatch control model, is the adjustment number of the i-th static reactive power compensation device, is the maximum daily switching times of the i-th static reactive power compensation device.

[0042] It should be noted that in terms of the constraint on the number of adjustments, in order to protect the service life of the static VAR compensation device, the number of switching times within a fixed time range must be limited during operation.

[0043] Genetic algorithm is an optimization and search algorithm based on the principles of natural selection and genetics. By simulating the natural evolution process, genetic algorithm can effectively explore the solution space and find approximate optimal solutions. It is a powerful optimization and search tool suitable for solving a variety of complex problems.

[0044] The improved genetic optimization algorithm is used to solve the reactive resource dispatching control model, specifically: The adjustment times of the static reactive power compensation device, a decision variable in the reactive power resource dispatch control model, is set as a value to be solved by the improved genetic optimization algorithm; A set of switching command values ​​of static reactive power compensation devices is generated by random function as the initial population of improved genetic optimization algorithm; Set the corresponding maximum number of iterations, and the optimization algorithm performs corresponding selection operations, crossover, mutation, etc. Compare the current solution with the previous optimal solution until the maximum number of iterations is reached, output the current optimal solution, and obtain the switching instruction of the static reactive power compensation device.

[0045] The switching instruction of the static reactive power compensation device is obtained as follows:

[0046] Where: TC is the switching instruction of the static reactive power compensation device, is the decision variable of the reactive resource dispatch control model, is the adjustment number of the i-th static reactive power compensation device, is the reactive power output value of the i-th static reactive power compensation device, is the reactive power output value of the ith dynamic reactive power compensation device, is the required reactive power compensation capacity.

[0047] The switching instruction of the static reactive power compensation device includes a switching state and operating parameters, specifically including the following contents: The switching state includes a switching instruction and a switching instruction. The switching instruction instructs the static reactive power compensation device to be connected to the power grid to increase reactive power, and the switching instruction instructs the static reactive power compensation device to be switched off from the power grid to reduce reactive power.

[0048] The operating parameters include reactive power value, operating time and priority, and specifically include the following: The reactive power value display specifically indicates the reactive power value to be switched, the running time indicates the effective time period of the instruction, that is, the duration, and the priority refers to the order of priority execution when multiple switching instructions exist at the same time.

[0049] The above formulas are all dimensionless and numerical calculations. The formula is a formula for the most recent real situation obtained by collecting a large amount of data and performing software simulation. The preset parameters in the formula are set by technicians in this field according to actual conditions.

[0050] The above embodiments may be implemented in whole or in part by software, hardware, firmware or any other combination. When implemented by software, the above embodiments may be implemented in whole or in part in the form of a computer program product.

[0051] Those of ordinary skill in the art will appreciate that the modules and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0052] In addition, each functional module in each embodiment of the present application may be integrated into one processing module, or each module may exist physically separately, or two or more modules may be integrated into one module.

[0053] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0054] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A multi-type reactive resource dispatching and control method for a power grid containing a high proportion of new energy, characterized in that: The following steps are involved: Acquire reactive device operation characteristic data, and determine the working order of the reactive compensation device according to the reactive device operation characteristic data, wherein the reactive device operation characteristic data includes static reactive compensation device operation characteristics and dynamic reactive compensation device operation characteristics; Based on the performance index of the reactive power compensation device, a reactive power resource dispatching control model is constructed in combination with the operating characteristic data of the reactive power compensation device and the working order of the reactive power compensation device; An improved genetic optimization algorithm is used to solve the reactive resource dispatching control model and output switching instructions for a static reactive power compensation device.

2. The multi-type reactive resource dispatching and control method for a power grid with a high proportion of new energy as claimed in claim 1 is characterized in that: The working order of the reactive power compensation device is determined according to the reactive power device operation characteristic data, specifically: The static reactive power compensation device is preset to perform a switching operation once every preset time period; When the static reactive power compensation device cannot meet the required reactive power compensation capacity, the dynamic reactive power compensation device will provide a one-time reactive power compensation according to the reactive power compensation capacity and a predetermined time interval.

3. The multi-type reactive resource dispatching and control method for a power grid containing a high proportion of new energy as claimed in claim 2 is characterized in that: The reactive resource dispatching control model includes establishing a reactive compensation device objective function based on the performance index of the reactive compensation device and constraint conditions of the reactive compensation device objective function.

4. The multi-type reactive resource dispatching and control method for a power grid containing a high proportion of new energy as claimed in claim 3 is characterized in that: The objective function of the reactive power compensation device is calculated as follows: Where: E represents the economic index of the adjustment cost of the static reactive power compensation device, α and β are the weight coefficients of the objective function of the reactive power compensation device, S represents the security index of the dynamic reactive power compensation device for the dynamic support of the grid voltage, is the decision variable of the reactive resource dispatch control model, is the adjustment times of the ith static reactive compensation device, C is the unit adjustment cost of the static reactive compensation device, is the reactive power output value of the ith dynamic reactive power compensation device, is the reactive capacity of the i-th dynamic reactive compensation device.

5. The multi-type reactive resource dispatching and control method for a power grid containing a high proportion of new energy as claimed in claim 4 is characterized in that: The constraint conditions of the objective function of the reactive power compensation device include power grid safety operation constraint, reactive power compensation device action constraint, and adjustment number constraint.

6. The multi-type reactive resource dispatching and control method for a power grid containing a high proportion of new energy as claimed in claim 5, characterized in that: The grid safe operation constraints include node voltage constraints and system power flow constraints, wherein the node voltage constraints are expressed as follows: Among them, the system power flow constraint is expressed as follows: Where: is the voltage of the ith node, is the set of lines with the grid operation node k as the terminal, is the set of lines with the grid operation node k as the starting point, i as the input node, j as the output node, M as the set of AC nodes, is the voltage of the ith node, is the active power on line ik collected based on the designed reactive resource scheduling control strategy framework, is the reactive power on line ik collected based on the designed reactive resource dispatch control strategy framework, is the equivalent resistance of line ik, is the equivalent reactance of line ik, The active power injected into the grid operation node k, Reactive power injected into the grid operation node k.

7. The multi-type reactive resource dispatching and control method for a power grid containing a high proportion of new energy as claimed in claim 6, characterized in that: The reactive power compensation device action constraint includes the reactive power compensation device output constraint and the static reactive power compensation device adjustment time interval constraint, wherein the reactive power compensation device output constraint is expressed as follows: The static reactive power compensation device adjusts the time interval constraint, and the formula is expressed as follows: Where: is the reactive power output value of the i-th static reactive power compensation device, is the reactive power output value of the ith dynamic reactive power compensation device, is the minimum value of reactive power output of the ith static reactive power compensation device, is the maximum reactive power output of the ith static reactive power compensation device, is the minimum value of reactive power output of the ith dynamic reactive power compensation device, is the maximum reactive power output of the ith dynamic reactive power compensation device, is the jth action time of the static reactive power compensation device, It is the minimum action time interval requirement for static reactive power compensation device.

8. The multi-type reactive resource dispatching and control method for a power grid containing a high proportion of new energy as claimed in claim 7, characterized in that: The constraint on the number of adjustments is expressed in the following formula: Where: is the decision variable of the reactive resource dispatch control model, is the adjustment number of the i-th static reactive power compensation device, is the maximum daily switching times of the i-th static reactive power compensation device.

9. The multi-type reactive resource dispatching and control method for a power grid with a high proportion of new energy as claimed in claim 8, characterized in that: The switching instruction of the static reactive power compensation device is obtained as follows: Where: TC is the switching instruction of the static reactive power compensation device, is the decision variable of the reactive resource dispatch control model, is the adjustment number of the i-th static reactive power compensation device, is the reactive power output value of the i-th static reactive power compensation device, is the reactive power output value of the ith dynamic reactive power compensation device, is the required reactive power compensation capacity.

10. The multi-type reactive resource dispatching and control method for a power grid containing a high proportion of new energy as claimed in claim 9, characterized in that: The switching instruction of the static reactive power compensation device includes a switching state and operating parameters, specifically: The switching state includes a switching command and a switching command, wherein the switching command indicates that the static reactive power compensation device is connected to the power grid to increase reactive power, and the switching command indicates that the static reactive power compensation device is switched off from the power grid to reduce reactive power; The operating parameters include reactive power value, operating time and priority. The reactive power value specifically indicates the reactive power value to be switched. The operating time indicates the effective time period of the instruction, that is, the duration. The priority refers to the order of priority execution when multiple switching instructions exist at the same time.

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