The complex voltage overcurrent protection is a standard configuration for inter-phase backup protection of main transformers in power plants.For a long time,due to the common use of this protection and its simple and clear principle,relay protection personnel have been prone to laziness,negligence,and carelessness in the setting calculation process.They directly provide empirical values rather than check and recalculate sensitivity of the protection.This results in substandard sensitivity of some transformers and consequently incompetence of protection mechanisms in promptness and accuracy,seriously threatening operational safety of transformer main equipment.This paper reveals the phenomenon of inadequate sensitivity in some cases through a voltage setting case of complex voltage overcurrent protection,proposes measures to solve the problem,perfects the protection scheme,corrects the protection setting,and enables the protection to more effectively,quickly and accurately island faults and protect electrical main equipment.
关键词
电厂/主变/复合电压/过流/保护/灵敏度
Key words
power plant/main transformer/composite voltage/overcurrent/protection/sensitivity
维普
万方数据