subtransmission meaning in Chinese

二次输电
辅助变速箱

Guide for the application of neutral grounding in electric utility systems , part v - transmission systems and subtransmission systems
公共用电系统中性接地应用指南.第5部分:输电系统和子输电系统
Guide for the application of neutral grounding in electrical utility systems ; part 5 : transmission systems and subtransmission systems
电力事业系统中性接地应用指南.第五部分:输电系统和辅助输电系统