基于PSCAD的500kV自耦变压器铁磁谐振过电压仿真

Simulation of Ferroresonance Overvoltage Caused By Commissioning 500 kV Auto-transformer Based on the PSCAD

随着铁心材质和技术优化,500 kV自耦变压器发生的铁磁谐振故障逐渐减少,但是在电网结构较薄弱的终端电站,由于不适当的调试方式,投切主变时依然有可能激发铁磁谐振。为解决上述问题,笔者以500 kV汗—塔华北电网典型终端工程为例,深入研究500 kV自耦变压器励磁特性,创新性的研发了BPA-PSCAD等值接口程序,实现了对长线合空变的不同调试方式下的谐振过电压、自然谐振频率、操作过电压和励磁涌流精确建模计算,提出了正确的启动调试方式,规避了谐振故障的发生,该研究对调试启动方案的制定提供了切实可行的依据,对终端电站的主变投切与运行具有直接的指导意义。

As the core material and technology optimization, the ferroresonance overvoltage caused by commissioning 500 kV auto-transformer gradually reduced. But in the thinner terminal station of the power grid structure, due to the improper way of debugging, the main transformer was still likely to inspire ferroresonance. To solve the above problems, the author take the terminal 500 kV Han-Ta stations of North China power grid as an example, on the research of the auto-transformer ferroresonance excitation characteristics, developed the BPA-PSCAD equivalent interface program, it modeled and calculated the possible ferroresonance overvoltage, natural resonant frequency, operating overvoltage and excitation inrush current in the starting mode of the long line and commissioning main transformer with no-load, to avoid the resonance failure occurs, it puts forward the right way to start debugging, the studyings for the debugging plans provides the feasible theory basis, it is significance for the terminal station of the main transformer to cut and run.