210MW机组励磁系统改造的设计与实现

山西漳泽发电厂210MW发电机型号为TBB2202EY3,该励磁系统控制方式落后,运行不稳定,不能满足DCS系统采集要求,决定对该励磁系统进行国产化改造。本文就原系统的特点及多年运行中存在的故障进行了分析,从原励磁方式不变、自励恒压调节方式的实现、他励调节方式的实现等三个方面提出了设计思路及要求。针对原回路存在缺陷,分别从灭磁电阻和过压保护回路的改进、励磁系统“热切”回路的改进提出了改造方案。经过试验调试,该方案已经成功地应用在4台同型号210MW发电机组上,并且运行稳定、可靠,有很强的推广性。

Design and Implementation of an Improved 210MW Transformer Excitation Control System

By analyzing the characteristics of excitation control system of an out-of-date transformer(TBB-220-2EY3)used in Shanxi Zhangze Power Plant and the faults occurred during past few years, this paper proposes a design method and requirements for the improvement of above-mentioned excitation systems from the following three aspects: Original excitation method keeps unchanged, implementing self-excitation with constant voltage and separate excitation. Aimed at the defects of the old system, this paper also proposes a plan to make improvement in field-suppressing resistor, the circuit of over voltage protection and thermal breakdown circuit of excitation, respectively. The plan has been implemented in 4 transformers of the same type and the steady and reliable operations of these units indicate that this plan is rather successful.