Patent ID: 8532918
Filing Date: 2013-09-10
Classification: B60L

Abstract:
1. A system for determining a position of a vehicle along an “x” direction on a guideway which comprises: a magnetic array mounted on the vehicle, wherein the array has a wavelength “λ”; a propulsion winding located on the guideway for carrying a propulsion current provided by a Linear Synchronous Motor (LSM) control for interacting with the magnetic array to cause propulsion of the vehicle; a position winding located on the guideway, wherein the position winding has the same wavelength “λ” and the position winding includes a first helical wire and a second helical wire, wherein the first and second helical wires are arranged co-axially about an axis with the axis aligned along the “x” direction and with the first and second helical wires spatially displaced from each other by “λ/4”; a transmitter located on the vehicle for interacting with the position winding to generate a first return signal from the first helical wire and a second return signal from the second helical wire; and a processor connected to the LSM control for receiving and evaluating the first and second return signals to determine position data for the vehicle on the guideway, wherein the position data evaluation is based on a ratio of the first and second return signals to cancel a vehicle distance dependent flux magnitude, and wherein the position data is electronically communicated to the LSM control for use in maximizing an interaction of the propulsion current in the propulsion winding along the guideway with the magnetic array on the vehicle, for optimizing propulsion of the vehicle.