一种新型双馈风电场次同步振荡抑制策略

A Novel Strategy for Suppressing Sub-Synchronous Oscillations in Doubly Fed Wind Turbines

中文关键词:双馈风机  阻抗分析  次同步控制相互作用  有源电力滤波器  自抗扰控制  抑制策略

keywords:doubly fed wind turbine  impedance analysis  sub-synchronous control interaction  active power filter  active disturbance rejection control  suppression strategy

中文摘要:针对双馈风机经串补并网引发的次同步控制相互作用（sub-synchronous control interaction，SSCI）问题，提出一种有源电力滤波器（active power filter，APF）谐波补偿控制策略。基于双馈风机（doubly fed induction generator，DFIG）和串补输电线路的等效阻抗电路，利用阻抗法分析了系统发生SSCI的原因和特性；设计有源电力滤波器，通过向有源电力滤波器内部控制器注入包含无功电流和振荡电流在内的谐波参考电流来抑制风电场的次同步控制相互作用，该谐波电流参考值可通过并网采样电流减去其有功电流获得，有功电流则通过对APF直流侧电压采用一阶自抗扰控制（active disturbance rejection control，ADRC）获得；仿真验证了所提APF补偿控制策略在抑制SSCI方面的可行性。

Abstract:In this paper， a harmonic compensation control strategy for an active power filter （APF） is proposed to address the issue of sub-synchronous control interaction （SSCI） resulting from series compensation in doubly fed induction generators.The causes and characteristics of SSCI are analyzed using the impedance method， based on the equivalent impedance circuit of the doubly fed induction generator and the series-compensated transmission line. The active power filter is designed， and the sub-synchronous control interaction of the wind farm is suppressed by injecting the harmonic reference current including the reactive current and the oscillating current into the internal controller of the active power filter. The harmonic current reference value can be obtained by subtracting the active current from the grid side sampling current while the active current can be obtained by means of ADRC at the DC-side voltage of the APF. The feasibility of the proposed APF compensation control strategy in suppressing SSCI is verified through simulation.