Coupled model of a magnetic actuator controlling a hydraulic cylinder and load

Magnetic pressures on nonlinear steel are shown to have lower values than typical hydraulic pressures and, thus, small magnetic actuators are often coupled to hydraulic circuits. A new method of modeling a typical electrical/magnetic/hydraulic/mechanical system is described. Results of electromagnetic finite-element analysis of a magnetic actuator are used in a SPICE circuit that contains the differential equations of a hydraulic valve, hydraulic cylinder, and mechanical load. The coupled model is used to compute typical transient pressures, flows, and motions. Due to fluid flow forces the mass of the controlled arm is shown to have a coupling effect on the armature motion of the magnetic actuator.