六相交直流同时供电发电机直流侧突然短路电流分析

通过适当处理六相交直流同时供电（双绕组）发电机两套绕组之间的耦合，建立了其d-q-0系统的简化学模型；在此基础上，应用海维赛德运算微积法和叠加原理，分析了其稳态和直流侧突然短路运行，给出了定子和转子的时间常数以及交流侧完整的短路电流表达式；通过适当简化处理，得出了估算交、直流侧最大冲击电流和最大电流到达时刻的计算公式，并与普通三相电机突然短路的最大电流估算公式进行了比较，得出了到达最大电流时刻提前的结论；通过试验验证该文所得结果。该文对两套绕组之间耦合的处理大大简化了双绕组发电机的数学模型，为分析双绕组发电机的其它性能奠定了基础；所得结论和所用方法同样适用于其它结构的双绕组发电机，具有普遍意义。

STUDY ON THE CURRENTS OF SUDDEN DC-SIDE SHORT CIRCUIT OF SIX-PHASE SYNCHRONOUSGENERATORS WITH SIMULTANEOUS AC AND BRIDGE RECTIFIED DC OUTPUT

By dealing with the electromagnetic coupling between two sets of windings, the simplified d q 0 mathematical model of six phase synchronous generators with simultaneous AC and bridge rectified DC output(double winding generators) is set up. Then by applying Heaviside's operational calculus and the principle of superposition, its steady state and sudden DC side short circuit operations are analyzed in detail. The time constants of the stator and rotor are given, and the complete expressions of AC side short circuit currents are obtained. By proper simplification,the formulae of the maximum value of DC side short circuit current and the time of the maximum short circuit current are obtained, which are compared with the results of the sudden three phase short circuits in usual three phase synchronous generators,the results show that the time of the maximum short ciruit current is ahead.Comparison between the computed and measured results demonstrates the validity of the theoretical approach developed.the dealing of coupling between two sets of windings simplifies the mathematical model of six phase synchronous double winding generators,the results and the approach developed are also suitable for other double winding generators.