Hybrid Excitation for a Wide Speed Range Linear Sinusoidal Area Variable Reluctance Resolver

Linear position sensors are used in linear control systems to provide position feedback and also for positioning in various applications. In harsh environments, the reliability of the custom position sensors is not granted. Resolver is a good candidate for position estimation in such conditions. However, conventional resolvers are usually employed in low-speed applications and their accuracy at high speeds is questioned. On the other hand, the proposed linear resolvers for high-/ultrahigh-speed applications lost their accuracy at low speed. To have a wide speed range sensor, a hybrid excitation linear sinusoidal area variable reluctance (LSA-VR) resolver is introduced in this article. The developed sensor has a simple structure with nonoverlapping winding. The field reconstruction method (FRM) is used in the design and optimization process. Then, the obtained results are verified by 3-D finite-element simulations in both ac and dc excitation voltages. Finally, the proposed resolver is prototyped and tested. The measurements approved the success of the developed sensor.