风电机组附加有功控制参数对系统低频振荡的影响

Impact of Supplementary Active Power Control Parameters of Wind Turbine on Power System Low-frequency Oscillations

附加有功控制环节使风机参与至同步机的机电振荡模式中,这使得系统功率振荡特性机理更加复杂,不利于附加有功控制环节的参数设计。为了研究风机附加有功控制对系统稳定性的影响,首先建立了考虑锁相环特性的风机与同步机动态作用的小信号模型;然后基于该模型利用阻尼转矩法分析了风机附加有功控制对系统振荡稳定性的影响机理,并提出了综合考虑系统等效惯性时间常数和阻尼比的附加有功控制环节系数设计方法;最后通过“10机39节点系统”的仿真结果量化分析了各系数对系统低频振荡稳定性的影响规律。结果表明,合理设置风电机组附加有功功率控制系数、滤波时间系数和锁相环带宽均能提升系统频率稳定性;理论分析的正确性也得到了验证。

The involvement of wind turbine in the electromechanical oscillation mode of a synchronous generator after the supplementary active control makes the system power oscillation characteristics more complex,which is not conducive to the design of the supplementary active power control parameters.In order to study the effect of supplementary active con-trol of wind turbines on system stability,firstly,we established a small-signal model of the dynamic action of the wind turbine and synchronous generator after considering the characteristics of the phase-locked loop,analyzed the influence of the supplementary active power control on the stability of the system oscillation based on this model using the damping torque method,and proposed a design method for the supplementary active power control parameters in which the equiv-alent inertia time constant and the damping ratio of the system were taken into consideration.Finally,the influence of each factor on the system’s low-frequency oscillation stability was quantified by the simulation recults of the 10-machine 39-node system.The results show that the reasonable setting of the supplementary active power control parameters,the filtering time parameters and the phase-locked loop bandwidth of wind turbines can improve the frequency stability of the system.The validity of the theoretical analysis is further verified.