Attractive force reducing strategy of LIM for PRT systems

An attractive force reducing strategy of LIM is proposed. The attractive force creates undesired power low, bending of the guide way, and severe tire wear. To reduce these defects, the motor flux must be reduced. In this paper, firstly, we simplify the attractive force relation with the application of a secondary flux reference control scheme. Then, we propose an attractive force reduction scheme which minimizes the power loss by rolling resistance and copper loss. To reduce the attractive force and power loss, a constrained optimization technique is utilized for a given thrust force command. Through the simulation study, the feasibility of the proposed scheme is demonstrated.