交流输电线路大容量固定式直流融冰装置的设计方案

Design scheme of large-capacity fixed DC de-icing device for AC transmission lines

设计并研制开发了一套固定式直流融冰装置,其容量较大,可以为500 kV交流输电线路提供直流融冰电流。根据现有的融冰交流线路参数,对该套装置设计研制过程中几个重要的方面,包括主电路设计、基本结构与参数、控制保护设计以及过电压与绝缘配合等做出较为详细的论述。其运行范围很大,导致其基本结构比较复杂,比如需要2个六脉动换流器并联运行,换流变压器采用Y/△接线,为小负荷融冰而配置一台较小容量的三相三绕组(Y/△/△接线)变压器,且需要配置交流和直流滤波器等。

A large-capacity fixed DC de-icing device is designed and developed and it can de-ice for 500 kV AC transmission lines.According to the current parameters of AC transmission lines,some of its important aspects are introduced：main circuit design,basic structure and parameters,control and protection design,overvoltage and insulation coordination.Its wide operating range leads to its complex structure：two parallel operating 6-pulse converters,Y / △ connection commutating transformer,small-capacity three-phase three-winding Y / △ / △ connection transformer for low load de-icing,AC and DC filters.