A double winding linear induction motor control scheme for PRT system

To increase fault tolerance, a double winding linear induction motor (LIM) is proposed for personal rapid transit (PRT) system. In the double winding LIM, two sets of windings are wound in a single yoke, and each of them are controlled by separate inverters. Therefore, the flux continuity must be provided in the region where the two windings are overlaid. Providing flux continuity is interpreted as aligning two flux angles. If the flux angles of two LIMs are not identical, then abrupt flux change occurs in the overlaid region, causing loss and coupling between two inverter systems. To align two flux angles, we propose a flux aligning controller by exchanging angle information through RS-232 communication and analyze its performance under the disturbance. We discuss the fault-tolerant operation algorithm and compare the PRT system with the other transport systems.