海洋核动力平台配电变压器低压侧三相短路电流计算与分析

海洋核动力平台的技术发展符合我国发展海洋强国战略的需求,本文针对海洋核动力平台单堆25MW级主电站的典型发电机配置和2MW级平台自用电配电系统,分析了启堆工况负荷转移的过程中存在两机短时并联的现象,计算了负荷转移过程中平台自用电配电变压器AC400 V低压侧的三相短路电流,给出了低压侧干线断路器设计与选型的技术规格,以及平台供配电系统设计的改进措施,为工程实践提供了参考依据。

Three Phase Short Current Calculation and Analysis of the Distribution Transformer Secondary Side on Marine Nuclear Power Platform

The marine nuclear power platform(MNPP)is being developed vigorously under the background of national marine development strategy in China.According to the typical main power plant configuration of 25MW outward distribution power and 2MW inward auxiliary power based on a single nuclear reactor,there exists a transient process of the single nuclear reactor generator and the diesel generator sets’simultaneous running in parallel mode for a short time,so as to transfer all the loads from the diesel generator set to the nuclear reactor generator set.Three phase short currents of the distribution transformer’s secondary side of AC400V in the case of short circuit during the transfer process are calculated,and based on this,the breaker technical specifications of the main circuit breackers at the transfermer secondary side are given,and meanwhile,the improvement actions for power system design are proposed,which provide reference for engineer practice.