position control of d. c. motors has been done by means of pulse width modulation . 直流电机位置用脉冲宽度调制法控制。
if an induction resolver is used then some electronic circuitry will be required to convert the resolver outputs to d. c. signals . 假如采用感应式分解器,那么就需要采用某种电子线路来把分解器的输出转换成直流信号。