试题详情

三相对称电压频率相同、幅值相等、相位互差(____)。

A30°$;$120°$;$90°$;$60°

B30°$;$120°$;$90°$;$60°

C30°$;$120°$;$90°$;$60°

D30°$;$120°$;$90°$;$60°