Constant speed hydrostatic drive system

摘要

A constant speed hydrostatic drive system is disclosed wherein a generator drive shaft is maintained at a constant speed by utilizing an electro-hydraulic controlled displacement pump responsive to a pressure transducer to control a hydraulic motor. A speed sensor is used to produce a direct current signal responsive to the drive shaft speed. The signal is converted into a series of voltage pulses also responsive to the shaft speed which are compared to a speed reference signal to provide a speed error signal. A loop gain control means is provided to utilize said speed error signal to adjust the shaft speed to coincide with said reference signal. A timing reference and digital trim control are also provided to compensate for long term drifting in the type speed control circuit described above.