Modelling of Solenoid Actuated Fast Switching Valve for Digital Hydraulic Machines

This paper investigates a solenoid actuator performance used for switching a valve used in Digital Displacement Machines (DDM), which is a developing fluid power technology that has rigorous valve requirements for obtaining a high efficiency including milli-second range switching time. The objective of the paper is to develop and validate a computational model, which is describing the actuator and the valve behavior. In order to estimate the switching time of the valve, a coupled simulation method is established. A transient electro-magnetic finite-element-analysis including moving mesh configuration is coupled to a dynamic motion interface, which includes a group of ordinary differential equations defining the movement of the valve plunger. In this model, the spring force, which lets the valve to open passively is coupled with the electromagnetic actuator force. Then, the results of the simulation are compared against measurements results obtained from a set of experiments based on a valve prototype. Comparisons of current and plunger position show that the model describes both the actuator and the valve motion very well.