Pilot valve device with differential control

The invention belongs to the technical field of fluid drive and particularly relates to a pilot valve device with differential control. The pilot valve device comprises a pilot valve body, an electrical-mechanical converter, valve bush driving rods and valve element driving rods, and further comprises a signal collecting and processing unit. The signal collecting and processing unit comprises a valve element displacement sensor, a valve bush displacement sensor, a valve element and valve bush displacement differential subtractor, a given feedback signal computing subtractor, a displacement (opening degree) given signal generator, a displacement (opening degree) signal converter, a voltage signal adjustor, a PWM signal generator, an electromagnet voltage signal transformer, a differential voltage amplifier, a valve element winding external wire, a valve bush winding external wire, a current signal sampler and a U'/U signal converter. Parameters of the electrical-mechanical converter element of a pilot valve ar