A Method for Improving Flow Control Valve Performance Based on Active Differential Pressure Regulation

The existing flow control valves (FCV) generally have problems with low flow control accuracy, high-pressure loss, and difficult flow fine-tuning. Therefore, this paper proposes a method of active differential pressure regulation (ADPR) to improve FCV performance. An additional controllable force is added to the compensator spool to change the force balance state, so as to realize the differential pressure regulation. Next, the strategies of disturbance compensation and nonlinear flow correction are designed. And the feasibility of the ADPR method and strategies are experimentally verified. The experiment results show that by continuously controlling the force, the differential pressure and flow of the FCV can be changed in proportion, and the flow range can be actively adjusted; compensating the flow force, the flow control accuracy of the FCV is improved, and the flow control error under steady-state load is reduced from 27% to within 7%; adopting the nonlinear flow correction strategy, the flow can change with the expected target flow, which has a good consistency.