Design And Analysis Of Permanent Magnet Synchronous Servo Motors For Industrial Robots

Industrial robots that replace the traditional manual labors have become a new restructuring and development trend of China’s manufacturing industry. At present, China has become the biggest market for industrial robots, but most of the high-end robots rely on import. The reason is that China’s servo motor, precision reducer, servo drives and other key technologies lag behind. Researching servo motors for industrial robots plays an important role in promoting china’s Industrial robot industry development and labor-intensive enterprises transformation. The content of this paper is one of the research contents of 2014 Guangzhou major project of production and research collaborative innovation "industrial robots development and application demonstration for the automated production of machine tools that based on industrial chain". The paper’s main work is to design and produce a 1.0kW permanent magnet servo motor. And the industrial robot will be applied in the automatic production.Firstly, the structure and working principle of permanent magnet synchronous servo motor are introduced in the paper. The special requirements of the servo motor for the industrial robot are analyzed. And the paper also analyzes the overload performance, speed regulation performance and torque ripple of permanent magnet servo motor.Secondly, Design and analysis of PMSM for industrial robot by using "Field-circuit analysis method". The motor’s structure and size, winding type and slot/pole combination are designed by the requirements of the project and PMSM design principles. Then, Rmxprt is used to calculate the design scheme based on magnetic circuit method. Maxwell2D software is introduced to determine the scheme of optimizing the air gap flux density and weaken cogging torque through the finite element method. The scheme of single-double layer winding is introduced and analyzed in detail. Last, the design scheme of this motor would be determined; the prototype of motor would be made and tested. The testing results show that the technical specifications and performance characteristics of the prototype meet the design requirements of the project. The torque ripple of the prototype is small; the overload ability of the prototype achieves the required 3.3 times; the speeding ratio achieves 1.5 times.Finally, conclusion about the whole essay is got. Proposing some design experience with reference value of PMSM, pointing out the deficiency at present and the direction of the study in the future have been discussed.Aiming at special requirements of overload and torque ripple of this industrial robot’s PMSM, single-double layer winding is adopted, which combines the advantages of simple structure of single layer winding and less harmonic content of double layer winding. And unequal thickness poles for weakening cogging torque are presented for investigations. The Maxwell 2D software is utilized to determine the extent of the permanent magnet poles of unequal thickness. This paper has a certain reference value for the design of permanent magnet servo motor.