含虚拟惯量的双馈风电机组扭振阻尼特性分析与抑制方法研究

Torsional Oscillation Damping Characteristics and Suppression Methods of Doubly-fed Induction Generator With Virtual Inertia

阻尼是影响双馈风电机组(doubly-fed induction generator,DFIG)轴系扭振的核心因素。在并网导则要求风电参与系统调频的背景下,当DFIG采用虚拟惯量控制响应系统频率变化时,其扭振的阻尼特性将更加复杂。采用阻尼转矩方法,首先分析了最大功率跟踪模式下DFIG轴系扭振的阻尼特性,推导了虚拟惯量引入后双馈风机的电磁转矩–转速环传递函数,解释了虚拟惯量控制降低DFIG扭振阻尼的原因。其次,分析了基于带通滤波器和相位补偿环节的扭振阻尼控制器(bandpass-filter and phase-compensation based torsional oscillation damping controller,BPB-TODC)附加于不同控制通道引起的扭振频率偏移问题。针对扭振频率偏移导致阻尼控制器性能下降的问题,在混合通道BPB-TODC基础上,通过对多扭振频率偏移场景下的控制器参数进行寻优,提出了抗扭振频率偏移的优化BPB-TODC。最后,通过仿真验证了上述理论分析的正确性和所提阻尼控制器的有效性。

Damping is the core factor affecting the drive-train torsional oscillation of the doubly-fed induction generator(DFIG).According to the Grid-Connected Guidelines,wind power is supposed to participate in frequency modulation.The shaft system’s torsional oscillation damping characteristics may become more complicated when the DFIG contains virtual inertia control.First,the torsional oscillation damping characteristics of the DFIG under the maximum power tracking control are analyzed when adopting the damping torque method in this paper.On the basis,the electromagnetic-torque-generatorspeed loop transfer function of the DFIG is derived after the virtual inertia control is introduced,which illustrates why the torsional oscillation damping is reduced.Secondly,the torsional oscillation frequency deviation caused by Bandpass-Filter and Phase-Compensation Based Torsional Damping Controller(BPB-TODC)attached to different power channels is analyzed.Aiming at the problem that the torsional oscillation frequency deviation degrades the performance of the damping controller based on the duel-channel BPB-TODC,this paper proposes the anti-torsional vibration frequency deviation by optimizing the controller parameters in the multiple torsional frequency deviation scenario.Finally,simulations verify the correctness of the theoretical analysis and the effectiveness of the proposed damping controller.