单项选择题

一台Y接法三相四极绕线式感应电动机,f 1 =50Hz,P N =150kW,U N =380V,额定负载时测得P cu2 =2210W,P Ω +P Cu =3640W.已知电机参数R 1 =R 2 =0.012Ω,X =X =0.06Ω,当负载转矩不变,电动机转子回路每相串入电阻R=0.1Ω(已折算到定子边),此时转速为______

A.1301r/min
B.1350r/min
C.1479r/min
D.1500r/min