PWM变频调速已成为异步电机最主要的调速方法,变频器在50Hz以下,设定V/F为恒定值,也即恒力矩输出。变频器在提升机上应用时,由于在提升过程中直流母线电压的波动,使得变频器易出现过压或过流故障,并且使电机发出异常声音的问题时有发生。“AVR功能”是解决这一问题的关键。 PWM frequency conversion speed control has become the most important asynchronous motor speed control method, the frequency converter below 50Hz, set V / F to a constant value, that is, constant torque output. When the inverter is applied on a hoist, the problem of overvoltage or overcurrent in the inverter is prone to overvoltage or overcurrent due to the fluctuation of the DC bus voltage in the hoisting process, and the problem of causing the motor to make abnormal sound sometimes occurs. “AVR function ” is the key to solve this problem.