Control system for electric motor

摘要

A four quadrant control system for a brushless D.C. motor wherein the windings are energized via a drive switching circuit in a bridge configuration and the switching circuit is in turn controlled by a read-only memory. Pulse-width modulation control signals and position signals are supplied to the read-only memory as addresses together with other control signals. The system operates in a regenerative mode when changing direction and automatically makes a smooth transition into a motoring mode when the back EMF of the motor is no longer large enough to satisfy the requirements of the current loop.