励磁系统换向过电压阻容保护装置的仿真研究

Study of RC Protection Equipment in Commutation Overvoltage Restriction by Computer Simulation

阻容式过电压保护装置广泛用于可控硅励磁系统周期性换相过电压的抑制,各种阻容保护方案的优劣及阻容参数的选取一直是现场应用的一大难点。为寻找阻容抑制的最佳方案并指导现场工程师合理选择参数,介绍了一种基于Saber建模仿真分析的方法,通过建立励磁系统及整流式、三角形、星型3种阻容保护方案的仿真模型,仿真分析了各种阻容抑制装置的抑制结果以及不同阻容参数配合下的抑制结果。结果表明:现场实测结果与仿真结果一致性好,具有良好的工程实用价值。

Periodic phase conversion overvoltage is inevitable tectors are widely used in SCR phase conversion overvoltage in silicon controlled rectifier excitation system. RC prorestriction. However, the solution selection and parameter coordination of RC device and is a popular problem for local engineers. In this article, a simulation model of SCR excitation system are founded based on system parameters of The three Gorge Power Plant. Three kinds of typical RC protect device are added into the simulation model. Simulation results are quite in accordance with the local test, from which we can easily differentiate which protection scheme is better and which parameter is better. It will be very useful for local engineers and the simulation result can be a very good reference for the application of RC protector in many other excitation systems. Simulation result also suggest the Triangle protection device are better for it have best restriction result and the Star protection device have lower power dissipation on resistors which can also be the best solution.