CN-122000911-A - Method, system, equipment and medium for suppressing harmonic resonance of offshore wind farm station

CN122000911ACN 122000911 ACN122000911 ACN 122000911ACN-122000911-A

Abstract

The invention belongs to the technical field of regional power grid power quality management and discloses a method, a system, equipment and a medium for suppressing harmonic resonance of an offshore wind farm station, wherein the method comprises the steps of calling the residual capacity of an offshore wind power access node, executing first harmonic compensation based on the residual capacity, and performing first evaluation on a regional power grid after the first harmonic compensation; if the primary evaluation does not meet the preset inhibition requirement, a cooperative inhibition mechanism is established by combining the active filter, the cooperative inhibition mechanism is used for carrying out secondary harmonic compensation, and the regional power grid after the secondary harmonic compensation is subjected to secondary evaluation, and if the secondary evaluation result still does not meet the preset inhibition requirement, the parameter configuration of the active filter and the utilization configuration of the residual capacity are subjected to iterative optimization by utilizing an improved particle swarm optimization algorithm, so that an optimal configuration scheme is obtained. According to the invention, the quantity of active filters is reduced, the treatment cost is reduced and the wind power compensation economy is optimized by cooperatively utilizing the residual capacity of wind power.

Inventors

ZHANG YAN
CI WENBIN
YANG BO
LI MING
HUANG ZHENNING
ZHANG BOYI
QIN JIAFENG
LIANG ZHENGTANG
SI JUNCHENG
CHEN CHEN
LIU WENHUA
WANG HUAJIA
GUAN MINGRUI
LIU PENGBEI
LI FUCUN
WU CHUANJIAN
CAO WENJUN
YU DANWEN
ZHANG QINGQING
WANG QINGYU
SU YONGZHI

Assignees

国网山东省电力公司电力科学研究院
国家电网有限公司

Dates

Publication Date: 20260508
Application Date: 20251205

Claims (16)

1. A method for harmonic resonance suppression in an offshore wind farm, the method comprising: Calling the residual capacity of the offshore wind power access node, executing first harmonic compensation based on the residual capacity, and performing first evaluation on the regional power grid after the first harmonic compensation; If the primary evaluation does not meet the preset inhibition requirement, a cooperative inhibition mechanism is established by combining the active filter, the secondary harmonic compensation is carried out by using the cooperative inhibition mechanism, and the secondary evaluation is carried out on the regional power grid after the secondary harmonic compensation; if the secondary evaluation result still does not meet the preset inhibition requirement, performing iterative optimization on the parameter configuration of the active filter and the utilization configuration of the residual capacity by using an improved particle swarm optimization algorithm until the secondary evaluation result meets the preset inhibition requirement, and obtaining an optimal configuration scheme.
2. The method for suppressing harmonic resonance in an offshore wind farm according to claim 1, wherein the calling the remaining capacity of the offshore wind power access node, performing the first harmonic compensation based on the remaining capacity, and performing the first evaluation on the first harmonic compensated regional power grid comprises: identifying harmonic source nodes in a power grid through load flow calculation and initial harmonic analysis, and calculating the sensitivity of harmonic voltages in the harmonic source nodes to compensation current of an active filter by using a harmonic propagation equation; Constructing a harmonic propagation matrix based on node and branch characteristics of the regional power grid, constructing a harmonic treatment sensitivity matrix by taking sensitivity as matrix elements, and combining a multi-harmonic source scene to obtain node comprehensive sensitivity; and sequencing all harmonic source nodes from high to low according to the obtained comprehensive sensitivity, and preferentially installing an active filter at the node with high comprehensive sensitivity.
3. The method for suppressing harmonic resonance in an offshore wind farm according to claim 2, wherein the sensitivity is expressed as: Where S h,ij represents sensitivity, U h,j represents the h-th harmonic voltage of node j, and I h,i represents the active filter compensation current of node I.
4. The method for suppressing harmonic resonance in an offshore wind farm according to claim 1, wherein the expression for calling the remaining capacity of the offshore wind power access node and performing the first harmonic compensation based on the remaining capacity is: in the formula, Representing available residual capacity of wind power resources; representing the residual capacity of wind power; the compensation current which indicates that wind power resources can be used for harmonic waves, and U B indicates reference voltage.
5. The method for suppressing harmonic resonance of an offshore wind farm station according to claim 1, wherein the iterative optimization of the parameter configuration of the active filter and the utilization configuration of the residual capacity by using the improved particle swarm optimization algorithm until a preset suppression requirement is satisfied, and the obtaining of the optimal configuration scheme comprises: According to the relation between wind speed and generating capacity, setting a double optimization target by combining the harmonic treatment requirement of the regional power grid, and determining constraint conditions, wherein the constraint conditions comprise active filter capacity constraint and wind power resource compensation constraint; Based on the uncertainty of wind speed, constructing a harmonic treatment optimization model by combining double optimization targets and constraint conditions; And solving the harmonic governance optimization model by utilizing an improved particle swarm optimization algorithm, and obtaining an optimal configuration scheme by using the parameter configuration of the active filter and the utilization configuration of the residual capacity as iterative optimization variables.
6. An offshore wind farm station harmonic resonance suppression method according to claim 5, wherein the double optimization objective comprises minimizing the maximum total harmonic distortion rate of the regional power grid and minimizing the total governance cost.
7. The method for suppressing harmonic resonance in an offshore wind farm according to claim 6, wherein the maximum total harmonic distortion is expressed as: Wherein maxTHD denotes the maximum total harmonic distortion, V h,i denotes the effective value of each subharmonic voltage, and V 1 denotes the effective value of fundamental voltage.
8. The method for suppressing harmonic resonance in an offshore wind farm according to claim 7, wherein the expression of the total governance cost is: C total ＝C APF +N time (C capacity +k wp C wp ); C APF ＝N APF ·c fixed ; Wherein C total represents total governance cost, C APF represents installation cost of an active filter, N time represents equipment operation time, C capacity represents operation and maintenance cost of the active filter, k wp represents wind power resource cost penalty coefficient, C wp represents wind power resource harmonic governance operation and maintenance cost, N APF represents number of active filters, C fixed represents fixed installation cost of each active filter, C unit represents operation and maintenance cost of the active filter, i represents index value, S i represents governance capacity of APF, C wp represents operation and maintenance cost of wind power resource governance harmonic, k represents wind power resource node, WP_nodes represents wind power resource node set; Representing the harmonic compensation current of the wind power resource node k.
9. The method for suppressing harmonic resonance in an offshore wind farm according to claim 8, wherein the constructing a harmonic governance optimization model based on the uncertainty of wind speed and combined with the double optimization targets and constraint conditions comprises: According to the relation between wind speed and generating capacity, the uncertainty of wind speed is identified, and a wind speed probability distribution model is constructed by utilizing Weibull distribution; Based on the double optimization targets and constraint conditions, probability constraints corresponding to the wind speed probability distribution model are converted into deterministic constraints through opportunity constraints, and a harmonic treatment optimization model is constructed.
10. The method for suppressing harmonic resonance in an offshore wind farm according to claim 9, wherein the method for solving the harmonic governance optimization model by using the improved particle swarm optimization algorithm, and using the parameter configuration of the active filter and the utilization configuration of the residual capacity as iterative optimization variables, and obtaining the optimal configuration scheme comprises: initializing parameters of a particle swarm optimization algorithm, defining the position of each particle as a combination of parameter configuration and residual capacity utilization configuration of an active filter, and judging whether the current iteration number exceeds a preset maximum iteration number based on an initialization result; if the current iteration number exceeds the maximum iteration number, outputting an active filter parameter configuration and residual capacity utilization scheme corresponding to the global optimal solution as an optimal configuration scheme; If the current iteration number does not exceed the maximum iteration number, calculating the fitness of each particle in the population according to the double optimization targets, updating the individual optimal solution and the global optimal solution of each particle based on the calculation result, updating the speed and the position of each particle, adjusting the inertia weight, continuously iterating until the current iteration number exceeds the maximum iteration number, and outputting the active filter parameter configuration and the residual capacity utilization scheme corresponding to the global optimal solution as an optimal configuration scheme.
11. A system for harmonic resonance suppression of an offshore wind farm, the system comprising: The primary evaluation unit is used for calling the residual capacity of the offshore wind power access node, executing primary harmonic compensation based on the residual capacity, and performing primary evaluation on the regional power grid after the primary harmonic compensation; the secondary evaluation unit is used for establishing a cooperative suppression mechanism by combining the active filter if the primary evaluation does not meet the preset suppression requirement, performing second harmonic compensation by using the cooperative suppression mechanism, and performing secondary evaluation on the regional power grid after the second harmonic compensation; And the configuration scheme acquisition unit is used for carrying out iterative optimization on the parameter configuration of the active filter and the utilization configuration of the residual capacity by utilizing the improved particle swarm optimization algorithm if the secondary evaluation result still does not meet the preset inhibition requirement until the secondary evaluation result meets the preset inhibition requirement, so as to obtain an optimal configuration scheme.
12. An offshore wind farm station harmonic resonance suppression system according to claim 11, wherein the primary evaluation unit is preceded by: the sensitivity calculation module is used for identifying harmonic source nodes in the power grid through load flow calculation and initial harmonic analysis, and calculating the sensitivity of harmonic voltages in the harmonic source nodes to compensation current of the active filter by utilizing a harmonic propagation equation; The comprehensive sensitivity acquisition module is used for constructing a harmonic propagation matrix based on node and branch characteristics of the regional power grid, constructing a harmonic treatment sensitivity matrix by taking sensitivity as matrix elements, and combining a multi-harmonic source scene to obtain node comprehensive sensitivity; and the active filter installation module is used for sequencing all harmonic source nodes from high to low in the obtained comprehensive sensitivity, and preferentially installing the active filter at the node with high comprehensive sensitivity.
13. An offshore wind farm station harmonic resonance suppression system according to claim 11, wherein the configuration scheme acquisition unit comprises: The target and constraint setting module is used for setting a double optimization target according to the relation between wind speed and generated energy and combining the harmonic treatment requirement of the regional power grid, and determining constraint conditions, wherein the constraint conditions comprise active filter capacity constraint and wind power resource compensation constraint; the optimization model construction module is used for constructing a harmonic treatment optimization model based on the uncertainty of the wind speed and combining the double optimization targets and constraint conditions; The configuration optimization module is used for solving the harmonic treatment optimization model by utilizing the improved particle swarm optimization algorithm, and obtaining an optimal configuration scheme by using the parameter configuration of the active filter and the utilization configuration of the residual capacity as iterative optimization variables.
14. The offshore wind farm harmonic resonance suppression system of claim 13, wherein the optimization model building module comprises: The probability distribution model construction submodule is used for identifying the uncertainty of the wind speed according to the relation between the wind speed and the generated energy and constructing a wind speed probability distribution model by utilizing Weibull distribution; the constraint conversion sub-module is used for converting probability constraints corresponding to the wind speed probability distribution model into deterministic constraints through opportunity constraints based on the double optimization targets and constraint conditions, and constructing a harmonic treatment optimization model.
15. A computer device comprising a memory and a processor, the memory storing a computer program, characterized in that the processor implements the steps of the method of any one of claims 1 to 10 when the computer program is executed.
16. A computer readable storage medium, on which a computer program is stored, characterized in that the computer program, when being executed by a processor, implements the steps of the method of any of claims 1 to 10.

Description

Method, system, equipment and medium for suppressing harmonic resonance of offshore wind farm station Technical Field The invention relates to the technical field of regional power grid power quality management, in particular to a method, a system, equipment and a medium for suppressing harmonic resonance of an offshore wind farm station. Background With the acceleration of global energy transformation, in particular to the continuous improvement of the permeability of wind power in a power system, the utilization of renewable energy sources is increasingly wide. According to the international energy agency report, by 2025, the global wind installed capacity is expected to exceed 1000GW, bringing significant benefits to clean energy. However, after wind power is connected to the power grid, since the power generation equipment of the wind power generation system uses nonlinear elements such as a Doubly Fed Induction Generator (DFIG) or a Permanent Magnet Synchronous Generator (PMSG) combined with a power electronic converter, the devices can generate characteristic harmonics (such as 5 times, 7 times, 11 times, etc.), and the characteristic harmonics are injected into the power grid through a common connection Point (PCC), so that voltage and current distortion is caused, and thus the power quality is affected. Especially under the condition of the aggravated fluctuation of wind speed and uncertainty of output, the traditional power grid harmonic wave treatment method is difficult to adapt to a dynamic wind power access scene, and the problem of harmonic pollution is increasingly prominent. Conventional harmonic remediation methods typically rely on passive filters (PPF) such as LC tuned filters or high pass filters, etc., which achieve suppression of harmonics by providing a low impedance path to bypass the harmonic current. However, the performance of PPF is strongly dependent on system impedance and load variation, and when a wind farm is connected to a system, especially in an offshore wind farm, due to the existence of a distributed parameter network such as a cable capacitor and a transformer inductance, these conventional passive filters often cannot effectively cover full-band harmonics, and once the system impedance drifts, parallel resonance may be caused, resulting in harmonic amplification, so that an ideal treatment effect cannot be achieved. In order to overcome the limitations of the conventional passive filter, an Active Power Filter (APF) is widely studied and applied in wind farms as a dynamic compensation technique. The APF can be equivalently a controlled current source, and the harmonic wave in the system is detected in real time and the compensating current with equal amplitude and opposite phase is injected, so that the accurate suppression of the harmonic wave is realized. Studies have shown that the APF can significantly reduce the Total Harmonic Distortion (THD) in a wind power access system, however, the optimization problem is still a challenge, and certain defects exist in the aspects of uncertainty of wind power resources, equipment collaborative optimization and system level overall planning. Currently, conventional APF optimization methods are mainly based on deterministic frameworks such as Genetic Algorithms (GA) or Particle Swarm Optimization (PSO), with minimum governance costs or Total Harmonic Distortion (THD) as objective functions, and the installation location of the APF is usually determined by tidal current calculation and sensitivity analysis. However, these methods fail to fully consider the volatility and uncertainty of wind power resources, and random variation of wind speed will lead to deviation of wind power output, so that the optimization scheme is difficult to adapt to the changed load condition in actual operation, and the risk of overtaking harmonic waves is increased. In addition, the residual capacity of the wind power resource can be used for harmonic compensation, and the reverse current is generated by modifying the control strategy of the wind power inverter, so that the additional hardware investment is avoided. However, the related research is insufficient for the collaborative mechanism research of APF and wind power resources, and focuses on the optimization of single equipment, and lacks system-level coordination and resource sharing. This limitation causes problems of low treatment efficiency, waste of resources, insufficient economy, and the like. Therefore, how to provide a method, a system, equipment and a medium for suppressing harmonic resonance of an offshore wind farm station is a problem to be solved at present. Disclosure of Invention The embodiment of the invention provides a method, a system, equipment and a medium for suppressing harmonic resonance of an offshore wind farm station, which are used for solving the technical problems in the prior art. According to a first aspect of an embodiment of the invention, a method for suppre