低压总进线断路器的选择与变配电室的接地

Selection of Low Voltage Main Inlet Circuit Breaker and Grounding of Transformer Room

从最基础的电路理论出发,通过供配电工程分析,说明变压器低压总进线断路器和联络断路器采用4极开关有明显缺陷,存在中性线故障断开的风险和增加建设成本,建议推广采用3极断路器。然后进一步提出进线断路器的选择与接地系统的关联性,最后总结出较为合理的接地方式,建议变配电室采用TN-S接地系统,推荐按IEC标准做配电室接地设计与施工。

From the most basic circuit theory,through the analysis of the power supply and distribution engineering,transformer low voltage into line circuit breaker and always contact circuit breaker using 4 pole switch has obvious flaws,the risk of neutral wire fault disconnection and increase construction costs,recommended using 3 pole circuit breaker,further put forward into the correlation of line selection and grounding system of circuit breaker,finally summed up the reasonable way of grounding,suggest substation grounding system adopts TN-S,recommended by IEC standard for substation grounding design and construction.