《电机与拖动基础》习题解答
第一章 直流电机原理
P33
1-21 一台并励直流发电机 =16kW, =230V, =69.6A, =1600r/min,电枢回路电阻
=0.128 ,励磁回路电阻 =150 ,额定效率 =85.5%.试求额定工作状态下的励磁电流、
电枢电流、电枢电动势、电枢铜耗、输入功率、电磁功率。
解： = = =1.53A = + =69.6+1.53=71.13A
= + =230+ =239.1V
= = =647.6W
= =17kW
输出功率 = = =18.7kW
1-29 并励直流发电机 =7.5kW, =220V, =40.6A, =3000r/min,Ra=0.213 .额定励磁
电流 =0.683A,不计附加损耗，求电机工作在额定状态下的电枢电流、额定效率、输出转
矩、电枢铜耗、励磁铜耗、空载损耗、电磁功率、电磁转矩及空载转矩。
解： = - =40.6-0.683=40A
P
1
= = =8932W
= = =84%
=9550 =9550 =24N·m
= Ra= 0.213=341W
= =150W
