Energization controller of electric motor

摘要

An energization controller for an electric motor maintains a desired chopping frequency without increasing a current amplitude. The energization controller is provided with chopping control device which turns off both first and second switching elements of energization circuits of an H-type circuit together with a coil of the electric motor for a predetermined period of time and then turns on only the second switching element when a value of current flowing through the coil exceeds a reference current value and which turns on both the first and second switching elements when the value of current flowing through the coil falls below the reference current value and the predetermined period of time elapses.