Abstract:Based on the theory of permanent magnet latching, an electromagnetic linear actuator (EMLA) for a fuel injector of engine was presented. Using method of equivalent magnetic circuit, the dynamic model of the EMLA was established. Eddy current, dimensions of components, and fringing effect were taken into account in modeling. Using PWM method and H-bridge driver circuit, the prototype of the EMLA was tested on the test bed. The experimental and simulated data agreed well and the model was validated. The results show that under 0.5MPa supply pressure, the transition time of the EMLA was 1.57ms over 0.25mm stroke. The EMLA had good transient characteristics and met the working requirement of the fuel injector. Furthermore, because of no holding current, the fuel economy of engine was improved.