Study Based On Control System Of Hybrid Suspension

Magnetic suspension technology is one of the technologies in electronics, mechanics, and control engineering and computer science. Magnetic suspension technology has broad application prospects in transportation, metallurgy, electrical appliances, machinery, materials and other aspects with characteristics of its non-contact to avoid friction and loss, to extend the life of the equipment, and to improve equipment operating conditions. But the most promising application is maglev transportation technology.This paper first introduces the background and the significance of china’s development magnetic suspension. The background of the mixed suspension, working principle, structure and advantages are elaborated. Two models for magnetic suspension system are analyzed. Traditional EMS suspension system in the structure is simple and reliable, and technically very sophisticated, but because of all the suspension forces from the electromagnetic-loop with great current and power. To solve these problems, this paper introduces electromagnetic permanent magnetic hybrid suspension system. Hybrid suspension system shows a great advantage in retrenching energy, but the difficulty and complexity of control is also a corresponding increased.The hybrid suspension system model is established through analysis and research of electromagnetic permanent magnetic suspension system. The electrical and mechanical equations are listed and established a hybrid system model through analysis of the system. The system’s state space equations are obtained with linear process in equilibrium, next its stability is analysed. The simulation results verify the system stability analysis.As the hybrid suspension system is unstable in open loop system, stability and effective control scheme is need. This paper analyzes several main control methods of suspension system, and study the state feedback control, PID control, optimal control, sliding mode control and fuzzy control. State feedback control scheme is discussed with emphasis, and the simulation results are given. Then, combine the PID control and fuzzy control to the hybrid suspension system, Fuzzy-PID control algorithm is presented, set detail parameter of simulink and get simulation results. And face to the open-loop unstable and a strong nonlinear characteristic of hybrid magnetic suspension system, a fuzzy approaching law sliding mode control strategy is introduced, and sliding mode variable structure controller is designed, and interrelated simulationts are shown.Simulation results show that using the fuzzy approaching law sliding mode control strategy, the system’s output gap value can be tracked the value of a given gap in a short time, and the system states can rapidly return to steady state in the face of disturbances, so, fuzzy approaching law sliding mode control strategy has superior adaptability than state space feedback control.