Research on the Characteristics of Pilot Controlled Electrohydraulic Directional Valve with High Speed On/Off Valve
Aiming at the problems of inaccurate flow control,large pressure impact and groundwater pollution of traditional hydrau-lic support using emulsion transmission medium electro-hydraulic reversing valve,a pilot proportional valve with water based high-speed switching valve was proposed,to achieve accurate control of the pressure of the main valve control chamber and the displacement of the main valve spool.A hydraulic bridge for pilot control of electro-hydraulic directional valve with high speed on-off valve was pro-posed.The compound PWM control strategy was proposed for pilot high speed on-off valve,reducing latency by 15.8 ms.The main valve displacement was controlled by pulse frequency modulation and pulse width modulation.The simulation results show that the displace-ment of main valve core can show proportional opening effect within a certain duty ratio range.The ultimate test findings indicate that using the high-speed on/off valve as a pilot stage enhances the response rate of the main valve.
high speed on/off valvecompound PWM control strategyposition controlresponse rate
万方数据
维普
