Development of Novel High-performance Double-stator Motor Drives for Direct-drive Robotics

Description

Robotics is identified as one of the key technologies for the next industrial revolution.Nevertheless, most of the focuses are on the robotic design of the control algorithm andthe artificial intelligent system. In the meantime, the key component of the drivingsystem for robotics, i.e., the electric machine still stagnates quite a lot. In fact, currentresearch works on motor designs for robotics obviously does not match the roboticdevelopment.In particular, the motor drives for the robotics have two main driving strategies –indirect-drive and direct-drive. The indirect-drive strategy takes the merit of inheritingthe high-speed motor design but suffers from the mechanical gear losses of wear-and-tearto achieve the desired high torque. Instead, by adopting the conventional low-speedmotor design, the direct-drive strategy is free from any gearing problems but suffersfrom definite lower performances. Thus, a new breed of high-performance motor drivesis pressingly needed to solve the above problems for direct-drive industrial robots andbiomorphic robots, which should achieve the desired high torque around the speed rangefrom 50rpm to 300rpm without any mechanical gears.Two major challenges are faced by the proposed motor design and control for direct-driverobotics. The first key challenge is how to design the motor topologies toincorporate the multipole winding arrangement or magnetic-gearing feature into thedouble-stator topology while offering the high performance and reliability for roboticoperation. Another key challenge is how to control the motor drives to accomplish thespeed-range extending and fault-tolerant operation.The purpose of this proposal is to develop a novel breed of double-stator direct-drivemotor drives for direct-drive robotics. The objectives are: (1) to develop the double-statordirect-drive motor topologies, which offer the low-speed high-torqueperformances; (2) to develop the armature winding connection approach for rangeextension in the low-speed regions; (3) to develop different operation modes for fault-tolerantoperation; (4) to develop a new numerical co-simulation approach to optimizethe design parameters and motor performances; (5) to develop a new power electronicmodule to perform the double-stator motor control with different modes of operation;(6) to evaluate the whole motor drive system in terms of technical performances forrobotic application and market values.