A new EMV system using a PM/EM hybrid actuator

In this paper, we develop a new EMV (electro mechanical valve) system using PM/EM (permanent magnet / electro magnet) hybrid EMA (electro magnetic actuator) and achieve the soft landing and the fast transition of the system using a simple PID control. Against the existing EMA using only the EM, the proposed actuator has several advantages like the PM biased AMB (active magnetic bearing) system. First, theoretical model of the proposed EMV system is derived and FE (finite element) analysis is performed to verify the theoretical model. Then, a test rig and a valve control system are built and the dynamic characteristic of the proposed EMA is identified. Finally, the soft landing and the fast transition of the system are achieved experimentally through a gain-scheduled PID control.