双馈感应发电机的线性化动态模型及运行特性分析

LINEARIZED DYNAMIC MODEL OF DOUBLY-FED INDUCTION GENERATOR AND ANALYSIS OF ITS OPERATING PERFORMANCE

对建立在定子旋转磁场坐标系中,以转子绕组励磁电压为控制变量的双馈感应发电机的3阶动态模型进行了线性化处理,得到了适用于小干扰稳定分析的双馈感应发电机状态方程和相应的传递函数。进而利用开环传递函数和根轨迹方法分析了发电机运行点与发电机动态品质的关系,并利用MATLAB软件对双馈感应发电机的控制变量在发生幅值不同的扰动变化时的动态响应做了对比仿真。该仿真分析将有利于了解双馈感应发电机的运行特性及掌握它的控制特性。文中提出的双馈感应发电机线性化模 型适用于变速恒频双馈风力发电系统的相关研究。

The 3-rd dynamic model of doubly-fed induction generator, which is established in the coordinate system of stator rotating magnetic field and uses the excitation voltage of rotor winding as control variable, is linearized, and the state equations of doubly-fed induction generator and corresponding transfer functions are obtained, which are suitable to the analysis of small disturbance stability. In addition, the relation between operating point of the generator and its dynamic characteristics is analyzed by use of open-loop transfer functions and eigenvalue locus method. The comparative simulation of dynamic response of the control variable of doubly-fed induction generator during the variation of disturbances with different amplitudes is carried out, and the results of this simulation will be beneficial to understand the running characteristics of doubly-fed induction generator and is helpful to master the features of its control. The presented linearized model of doubly-fed induction generator is suitable to the related researches of doubly-fed variable speed wind turbines.