场路耦合双馈感应风力发电机负载性能的分析与计算

Load Performance Analysis and Calculation of Double-fed Induction Winding Generator Based on Field and Circuit Coupling

为了详细分析双馈感应发电机的运行电磁性能,利用电磁场理论和变分法建立了双馈风力发电机运行时的数学模型,给出了利用有限元法求解二维瞬态电磁场的方法。为满足变速恒频恒压的要求,在计算过程中,将电机电磁场的有限元计算与外部电路相结合,以定子端电压为约束条件,对转子励磁电压进行了迭代求解,计算出了不同转速、不同负载下电机的性能曲线,并把计算结果与实测结果进行对比,表明采用有限元法计算得到的数值曲线能满足风力发电系统变速恒压恒频要求,为今后设计双馈风力发电系统提供了参考依据。

For analysis detailedly of the electromagnetic performance of double-fed induction generation, electromagnetic field theory and calculus of variations are used to establish the mathematic model of double-fed wind generators, while the two-dimension transient electromagnetic field finite element method is given. To satisfy varied speed, constant frequency and constant voltage, the electromagnetic field and out circuit are coupled, the stator terminator voltage is taken as constraint condition. Through iterating the rotor field current, the performance of double-fed wind generators at different speed and different load is calculated. The calculated results and experiment results are compared to imply that the calculated result satisfy the varied speed, constant frequency and constant voltage. All these provide some useful reference for winding generating system.