In a induction motors fed by a PWM voltages sour ce inverter, the insulation system endures much higher stresses, so that its rel iability will be affected.

• 与电网供电相比，变频器供电的异步电机绝缘系统承受了更高的应力，因而有必要以新的标准对变频电机的绝缘系统进行重新考虑。