考虑集电网结构的海上风电场谐振研究

Research on resonance of offshore wind farm considering electricity collection system

海上风力发电已经成为风电领域的重要发展方向。海上风电场中大量应用海底电缆进行电力传输,其较高的对地电容使得风电场的谐振问题更加突出。风电场集电网结构决定了电缆的长度、电气参数与连接方式,直接影响系统的谐振频率与强度。建立了海上风电场电力传输系统的谐波模型,包括风电机组、电缆与变压器模型等。基于模态分析方法,对不同集电网结构下系统的谐振情况进行了仿真计算,并由各节点参与因子分析谐振的主要来源;采用元件参数灵敏度分析方法,评估了主要结构参数对谐振的影响程度;进而针对不同频段谐振给出滤波措施。仿真结果验证了谐振抑制的有效性。

The offshore wind power is becoming an important development direction in the field of wind generation. In offshore wind farm, submarine cables are widely used to transmit power, which makes the resonance problem more serious due to the cables＇ high grounding capacitor. The power collecting system determines the cables＇ length, electric parameter and connection type, which directly affects the resonance frequency and impedance. This paper builds the resonance model of offshore wind farm transmission system, including wind generators, cables and transformers. Using modal analysis method, the resonance situations under different power collecting systems are simulated and calculated. The key nodes causing resonance are located by the participation factor. The main parameters＇ influence on resonance is evaluated with parameter sensitivity analysis. Finally, the filtering solution is proposed for different resonance frequency, which is proved to be effective by simulation results.