基于自适应有源阻尼的宽频域谐振抑制器

Wide-Band Resonance Suppressor Based on Adaptive Active Damping

风电机组经串、并联补偿并网可以降低线损,并有效提高线路送电功率和系统运行的稳定性,但补偿电容与风电机组控制装置之间的相互作用可能会引发包括次同步谐振和高频谐振的宽频域谐振稳定性问题。考虑串补、并补两种并网线路类型推导并建立了双馈风机并网系统的阻抗模型,利用阻抗法分析风机并网系统宽频域谐振的发生机理提出并设计了一个自适应宽频域谐振抑制器,将其并联连接到公共耦合点(point of common coupling,PCC),通过提取PCC点谐振电压并利用谐波含量限制的方法合成一个阻尼电阻以抑制系统产生的宽频域谐振。最后在MATLAB/Simulink中搭建了风电并网系统等值系统模型,通过时域仿真验证了该自适应宽频域谐振控制器的正确性和有效性。

Wind turbines connected to the power grid through series and parallel compensation can reduce line losses and effectively improve line transmission power and system stability.However,the interaction between the compensation capacitor and the wind turbine control device may cause a wide-band resonance stability problem including sub-synchronous resonance(SSR)and high frequency resonance(HFR).Considering two types of grid-connected lines,series compensation and parallel compensation,the impedance model of doubly-fed wind turbine grid-connected system is deduced and established.An impedance method is used to analyze the mechanism of wide-band resonance of wind turbine grid connected system,and an adaptive wide-band resonance suppres⁃sor is proposed and designed,which is connected in parallel to the point of common coupling(PCC).By extracting the resonant volt⁃age of PCC and using the method of harmonic content limitation,a damping resistor is synthesized to suppress the wide-band resonance generated by the system.Finally,an equivalent system model of wind power grid integration system is built in MATLAB/Simulink,and the correctness and effectiveness of the adaptive wide-band resonance suppressor are verified by time domain simulation.