Design of Position Estimator for Propulsion Inverter Driving Long Stator LSM in High Speed Maglev

Abstract

Abstract – In the case of long-stator linear drives, unlike rotative drives for which speed or position sensors are a single unit attached to the shaft, these sensors extend along the guideway. The position signal transmitted from maglev vehicle can ’ t meet the need of the real-time propulsion control. In this paper the position estimator for propulsion inverter driving long stator linear synchronous motor (LSLSM) in high speed maglev train is proposed. In order to get the higher resolution of the position information transmitted from vehicle, Full order state observer is proposed for position estimator. Keywords: Long Stator Linear Synchronous Motor, Position estimator, Propulsion Control, Full Order State Observer, Maglev 1. Introduction state observer is used forDuring past years, high speed maglev train based on Long Stator Linear Synchronous Motor (LS-LSM) is commercialized in Shanghai, China. The position signal of Transrapid train is key to drive propulsion inverter with LS-LSM. In MLX maglev system, it lays cross-induction coil in the middle of rail, which radiates high-frequency signals. When the train passes through the coil, it leads to the change of magnetic flux in the coil, from which we can obtain the accurate and precise position of train. Moreover, in TR maglev system the measuring method of the incremental vehicle location system INKREFA) provides the basic information for the location-related train control. The contactless determination of the absolute position of the vehicle on the guideway occurs redundantly, so that individual errors do not impose any operating restriction [1]. The detected position signals are transmitted to the propulsion inverter installed in ground by communication through radio using the RS-485 communication protocol with the cycle of 20ms and the transmission rate of 512kbps. However, the transmitted signal to propulsion control system can’t meet the need of the real-time propulsion control [2]. In this paper, the position estimator with Full order state observer is proposed in order to get the higher resolution of the position information transmitted from vehicle. Simulation results show the proposed strategy can meet the dynamic property need of propulsion control system with long state linear synchronous motor. Full order the position estimator.