Objective To address the issues of significant braking force dispersion, long braking response times, and high braking impact of maglev trains, an application study of EMB (electro-mechanical braking) technology on maglev vehicles is carried out.

Method The whole-vehicle braking system architecture based on EMB is constructed for a 200 km/h medium-speed maglev train, and a prototype of the EMB system is developed. Based on the classic PID (proportional, integral, and derivative) control, the closed-loop response characteristics of the system are studied. A fuzzy control algorithm is introduced for the closed-loop braking force control. This control is conducted by controlling the DC motor drive PWM (pulse width modulation) signal, and sampling the current value converted from its feedback current and the actual braking force value collected by the force sensor. The hardware design is carried out using a DSP (digital signal processor) chip, integrating the fuzzy control algorithm into the control circuit. The hardware-in-the-loop test of the EMB control system is thus achieved, verifying the performance of the fuzzy control algorithm. Vehicle system integration tests are conducted to verify the feasibility of the optimized closed-loop control algorithm based on current, speed, and braking force.

Result & Conclusion  The proposed EMB system demonstrates shorter braking response times, superior braking force control accuracy, and better tracking effects. It can effectively suppress the issue of significant braking force dispersion.