Design and Control of a Novel Wireless Permanent Magnetic AC Motor With Compact Structure

Wireless motors employ wireless power transfer (WPT) technology to convert electrical power into mechanical power remotely, eliminating the need for physical wires or cables. However, traditional wireless motors, especially wireless ac motors, still suffer from complicated and bulky motor-side circuits, intricate current commutation, and inefficient control processes. To improve the wireless ac motor, this article proposes a novel permanent magnetic ac (PMAC) motor system with minimized motor-side components. Initially, three independent WPT channels were established to enable simultaneous transmission of control data and power to the motor side, facilitating complete control from the primary side. Furthermore, the secondary-side power switches automatically toggle, functioning at a low motor electric frequency, obviating the requirement for supplementary control circuits and auxiliary power sources. In addition, current vector control with adjustable amplitude is introduced to generate rotating stator magnetic fields, enabling closed-loop motor speed control. Finally, an 800 r/min, 1.8 N·m wireless PMAC wireless motor prototype with 84.3% efficiency is constructed to validate the effectiveness of the proposed system.