主变冷却器二次回路安全可靠及经济运行的措施

Safe Reliable and Economic Operation Measures of Main Transformers Cooler Secondary Circuit

上海上电漕泾发电有限公司2×1 000 MW机组的主变由保定天威保变电气股份有限公司生产制造,型式为380 MVA/500 kV单相无载调压低损耗变压器,采用强迫油循环风冷方式。通过对实际运行中发生的事例进行分析,发现主变冷却器二次回路的设计中存在问题,尤其是主变冷却器全停保护回路有明显缺陷,在冷却器本身故障全停时,冷却器全停保护将不能正常启动,其保护动作出口继电器也易引起人员误碰事故的发生。冷却器相关报警信号不完善,不利于运行监盘人员及时发现设备缺陷。通过对以上问题的分析并采取行之有效的改进措施,上述问题得以解决,同时对主变不同工况下冷却器的运行方式采取优化调整措施,确保其经济节能运行。

Shanghai electric power caohejing Co., Ltd. has 2×1 000 MW units, whose main transformers are manufactured by baoding tianwei transformers electric company. It’s single phase no load voltage regulating low loss transformer and belongs to 380 MVA/500 kV,which applies forced oil circulation air cooling mode. Through actual accidents during practical operation, the author finds there is existing problems in main transformers cooler secondary circuit, especially main transformers cooler full-stop protection circuit shortcomings. Coolers fully stop when cooler full-stop protection is not functional and its outlet relay may cause human errors. Related alarm signal is not complete, which is not fit for operation supervision. Through analyzing and dealing above problems, the author also optimizes it with feasible measures. Under different conditions coolers operation is optimized and mains economic and safe operation.