单项选择题
A.1%~5% B.5%~10% C.10%~15% D.15%~20%
A.1.05~1.1倍 B.1.1~1.2倍 C.1.2~1.3倍 D.1.3~1.5倍
A.两极功率平衡 B.两极电压平衡 C.两极电流平衡 D.两极换流器触发角/关断角相等