Study on control performance of pilot high-speed switching valve

Abstract

High-speed switching valves have been widely studied as pilot valves because of their advantages on easy digital control, low power loss, and non-sensitive to oil pollution. However, there are still lots of difficulties and problems between discrete flow and response time. In this article, two high-speed switching valves are used to pilot a three-way main stage valve. By adjusting the duty ratio of pulse width modulation control signals, the main stage can output continuous flow and pressure. The control performances of two pilot stage methods, which are high-speed switching valve and proportional valve, are compared through the theoretical analysis and the dynamic simulation. It is found that three factors directly affect the response time of the main stage, which are the control signal, the operating frequency of high-speed switching valve, and the pressure of the control chamber. The main valve can achieve better performance if optimized parameters are applied.