Abstract
Electrohydraulic valves are crucial components in hydraulic systems, especially for the flow control or velocity control. With increased accuracy requirements of hydraulic drives, the electrohydraulic valves are required to have precise flow mapping. Starting with research on flow mapping under consideration of control signal, pressure drop and temperature, the novel flow mapping formula for flow mapping of electrohydraulic valves has been deduced. Through theoretical and experimental investigation, temperature influence on flow mapping could not only be qualitatively but also quantitatively analyzed. In particular, the mechanism of temperature affecting flow rate is further revealed. To verify the new flow mapping formula of the electrohydraulic valves, a test rig in laboratory has been set up. In order to obtain the evolving flow mapping of a Valvistor valve, the flow mapping formula at the institute has been applied and exemplified. The comparison with the experimental data indicates that the developed formula shows promising capabilities to describe the temperature influence on the flow mapping of electrohydraulic valve accurately. At the end, the capabilities of the developed solution are shown with a virtual real-time demonstrator accessed via an OPC UA data link inside a simulation environment with consideration of temperature compensation for feedforward control.
