Research on Driving Circuit Improvement of Coilgun

Theoretically, the energy conversion efficiency of the synchronous induction coil launcher (SICL) can reach 100%, but at present, the test data show that the highest current is only a little higher than 20%, which shows that the efficiency of the coil launcher has a lot of room for improvement. In this paper, three improved schemes are proposed for the topology of the traditional crowbar circuit based on the pulse capacitor to improve the electromechanical energy conversion efficiency of the electromagnetic coil launcher. They are main circuit breaking, crowbar break-off circuit, and crowbar circuit with inductor, respectively. In order to verify the feasibility of the above three methods, a five-stage coil launcher was simulated and analyzed. Then, based on the model, three improved circuits were calculated and analyzed by the finite-element simulation software. The results show that all of the three methods can improve the efficiency of energy conversion to a certain extent. Both the first and second methods have limited effect on increasing efficiency. In addition, they need to add some expensive equipment such as circuit breaker. So, they are not recommended. The third way of increasing an inductor in the crowbar circuit could increase the muzzle velocity and efficiency obviously. The muzzle velocity increased from 30.6 to 35 m/s. The effect of armature capture is reduced which is worthy of recommendation.