Method and apparatus for inductive load control with current simulation.

摘要

A control for an inductive load (12) switches current on and off to regulate about a command value, a decaying recirculation current flowing through the load during the switch off periods. The current is sensed during the switch on periods and charges a capacitor (42) to provide a simulation signal representing the motor current. The capacitor is allowed to discharge through a resistor (44) during the switch off periods at the rate of the decaying recirculation current. The simulation signal is compared to the command value to control the switching. The simulation signal is sensed during a command value of zero current to determine offset errors for calibration purposes.