Innovative Winding and Tooth-Pole Configurations in the Development of Variable Reluctance Synchro

Abstract

Traditionally, synchros utilize brushes and sliprings, which introduce significant noise into the output signal and limit their accuracy. These inherent limitations restrict their application in high-precision control systems. While rotary transformers (RTs) eliminate the issues of brushes and slip rings, they come with other trade-offs. Despite these limitations, synchros have competitive advantages over resolvers, such as reliability and fewer wires. Motivated by the need to address these limitations, this research presents an advanced synchro scheme that prioritizes simplicity and cost-effectiveness. This new scheme employs a single stator and a non-wound rotor, with both the exciting and signal windings conveniently located on the stator. A streamlined method is implemented to arrange the winding configurations for the proposed synchro, utilizing a nonoverlapping on-tooth winding technique with a constant number of turns. This technique provides significant versatility, allowing it to be applied to synchros with different pole counts and varying numbers of stator teeth. To evaluate the performance of the proposed synchro, an analytical assessment was conducted using a time-stepping finite element method. The results are validated through experimental tests on a prototype variable reluctance (VR) synchro, confirming the theoretical foundations of the proposed scheme.