Pulsed current revs. control for electric motor - uses controlled switching of current regulator switches to maintain constant mean power loss

摘要

The rev control allows continuous adjustment of the motor revs, by using pulse width modulated signals for controlling the semiconductor switches in the current regulator supplying the electric motor. The frequency of the ON-OFF switching of the semiconductor switches is determined by the current and/or voltage in the switched current circuit. The switching-in and switching-out power losses and the power loss during operation of the semiconductor switch are inserted in a given differential equation for determining the mean power loss which is held constant by varying the other terms. ADVANTAGE- Ensures optimal utilisation of semiconductor switches.