Abstract: In order to improve the response performance of electro-mechanical converter (EMC), a novel EMC device with triple coils was investigated in this paper. Mathematical model of the proposed EMC was firstly established. By applying the Bacterial Foraging Algorithm, an optimal solution for the model can be obtained. Adual-mode controller with Bang-Bang & proportional-integral was designed based on the proposed method. Analytical and simulated results showed that, response time of the triple coil EMC driven by dualmode controller can be reduced from 8.5 ms to 2.5 ms. In comparison with conventional single coil EMC, the ringing and overshoot can be controlled within 5%.