Driving electrohydraulic pressure supply for motor vehicle auxiliary power generator e.g. for powered steering

摘要

The method involves operating a hydraulic pump system using an electric motor which is only switched from a standby mode into a load mode when required. The changeover of the electric motor from standby to load mode or vice-versa is performed according to the engine speed. The motor is changed to load mode when the speed deviation lies above a first threshold for greater than a defined period. The motor is changed to standby mode when the speed lies above a second threshold for greater than a second period.