10kV配电变压器保护配置方式的合理选择

Rational selection of protection disposition modes for 10 kV distribution transformers

10kV配电变压器的保护配置主要有断路器、负荷开关或负荷开关加熔断器等。负荷开关投资省,但不能开断短路电流,很少采用;断路器技术性能好,但设备投资较高,使用复杂,广泛应用不现实;负荷开关加熔断器组合的保护配置方式,既可避免采用操作复杂、价格昂贵的断路器,弥补负荷开关不能开断短路电流的缺点,又可满足实际运行的需要,该配置可作为配电变压器的保护方式,值得大力推广,为此,对10kV环网供电单元和终端用户10kV配电变压器采用断路器、负荷开关加熔断器组合的保护配置方式进行技术-经济比较,供配电网的设计和运行管理部门参考。

The protection disposition modes for 10 kV distribution transformers mainly include circuit breakers,load switches or load switches plus fuses.The load switch,although economic,is seldom used for its incapability of breaking shortcircuit current.The circuit breaker,despite its good technical performance,is impractical for widespread use due to the high investment and the complicity in operation.The mode of load switch plus fuse,not only avoiding the use of complicated and expensive circuit breaker,remedying the incapability of load switch in breaking shortcircuit current,but also satisfying the requirements of practical running,merits wide spreading as a protection mode for distribution transformers.A technoeconomic comparison is also made between the breaker mode and the load switch plus fuse mode for 10 kV ring mains unit (RMU) and 10 kV distribution transformers of endusers,so as to provide reference for the design of distribution power network and operation administrators.