Minimizing the Number of X/Y Capacitors in an Autonomous Emergency Brake System Using BPSO Algorithm

This article proposes an efficient model to reduce the conducted emission in a motor-driven autonomous emergency braking system. Many X/Y decoupling capacitors have been employed in this system to repress the switching noises, which is a very important consideration for the reliability/safety of the system. However, the locations of the decoupling capacitors, have basically been determined, thus, far by trial and error. The proposed model, in this article, consists of a circuit of the permanent magnet synchronous motor-driven braking system which is combined with electromagnetic simulation models, and the whole models are integrated into a SPICE simulator. The effect of decoupling capacitors was analyzed, and a binary particle swarm optimization algorithm was applied to determine the most effective decoupling capacitor locations to minimize the number of capacitors in the system. An automation program with the optimization algorithm was developed using Python language. The optimized results showed the number of decoupling capacitors could be reduced from 36 to 28 in the specific motor-driven autonomous emergency braking system while still satisfying the electromagnetic interference specification of automaker requirements, which validates the effectiveness of the proposed methodology.