励磁系统动态增益对凸极发电机暂态稳定的影响

Because the dynamic gain of excitation system has significant impact on the dynamic stability of the salient pole generator, in order to improve the power system damping, it is often necessary to adjust the dynamic gain and deploy the power system stabilizer (PSS). However, there are some vague understandings for the influence of dynamic gain on generator transient stability, which hinders the development of related work. First, the relationship between transient stability and synchronous torque of the generator is analyzed, and the influence study of dynamic gain of excitation control system on transient stability is transformed into the influence study on synchronous torque for mathematical derivation. Then, the mechanism of dynamic gain of the excitation control system affecting synchronous torque of the salient pole generator is deduced and calculated, followed by the simulation of single-machine, two-machine and actual systems. The results of calculation and simulation show that when the dynamic gain of the excitation system changes in a normal range, its influence on transient stability of the salient pole generator is very small and can be neglected. When the dynamic gain of the excitation control system is adjusted in the normal range to improve the power system damping, the transient stability of the salient pole generator will not be significantly affected.