根据三相三线有功电能表的错误接线，见图所示，绘出其感性负载时的相量图，并写出功率表达式。<br /> <img src="https://nimg.ppkao.com/2018-09/tangxueping/2018093009341042170.jpg?sign=23b664d9605a6c58b81a082d664a41e9&t=62d12903" />