A Suppression Circuit for the Current Pulse during Digital Valve Drive

As an important research direction of the hydraulic system, the digital hydraulic system has attracted wide attention. Digital valve is a typical component in digital hydraulic system. The digital valve is robust to oil contamination and has low price, and it has two states: on and off. On the one hand, in order to improve the response, the digital valve is supplied by high driving voltage to open. On the other hand, in order to reduce the current, the digital valve is powered by low driving voltage to keep open. However, the above dual voltage driving mode to improve response will lead to the current pulse, which will cause a shock to the power supply. Therefore, a current suppression circuit based on supercapacitor was proposed. A simulation model of suppression circuit was built by using MWorks simulation platform. And the circuit was verified based on the simulation model. A series of experiments were completed according to the simulation to select appropriate parameters. The results show that the suppression circuit reduce the power supply current effectively. The supply current is reduced by 71 percent at most.