As the existing great power consumption of empty-load or light-load, the bipolar PWM control can be applied only in small or middle powerservocontrol systems.
在轻载或空载时由于存在大的功率损耗，双极性PWM控制只能被应用于中、小功率伺服控制系统。
2
Vehicle power steering systems control direction and flow of pressure oil with servo valves, then transfer angular inputs from steering wheels to corner angular outputs of road wheels.
According to the structure of servo mechanism on HD2se-ries pump, their functions have been analyzed. The structure and control process of constant power valve are mainly discussed.