Research On Control Strategy Of Servo Motor In Quadruped Robot

With rapid development of industrial automation,robots have greatly improved the production efficiency of human society and gradually liberated the human from manual labor.Nowadays,robots gradually penetrate into every aspect of our lives,including quadruped robots.In the sense of bionics,the quadruped robot simulates the tetrapod in nature,and it can flexibly work on various complicated terrains to helping people complete difficult tasks.Due to its wide application,the quadruped robot have become a research focus in recent years.Permanent magnet synchronous motors(PMSM)have the advantages of simple structure,high power density,and high efficiency.In recent years,the digital AC servo system,which uses PMSM as drive motors with high-performance control strategies,has been a research hotspot in electrical transmission.The digital AC servo system provides a more efficient,reliable and digital power drive option for the quadruped robot,therefore,the research on the AC permanent magnet servo system is of great significance.Firstly,PMSM was analyzed mathematically,and every detail of PMSM servo control system was introduced,such as the transformation of commonly used coordinate systems,the principle of vector control,and the SVPWM modulation technology.Secondly,for the purpose of overcoming speed fluctuation and current distortion when PMSM works at overmodulation region,a novel flux-weakening control algorithm was proposed in this paper.Comparing to the traditional flux-weakening control strategy by MATLAB/Simulink,the effectiveness of the algorithm was verified.Finally,control strategies of current loop was taken into research.To improve dynamic response,a current predictive control algorithm was used in this paper.However,traditional current predictive control depends on accurate motor parameters.This paper proposed an improved current predictive control,whose performace is better when the parameters are mismatched.The algorithm was verified by MATLAB/Simulink and experiments,and the results proved the superiority and effectiveness of it.