The Strategy For Improving Key Performance Of AC Servo System

With the implementation of " Made in China 2025 " strategy, the upgrade of manufacturing industry in China is on the road. As the important part of the advanced machining center, industrial robots and other products, the research on performance of AC servo drives has great significance.In this thesis, rotor field oriented technology is used as the basic control scheme of the system. The d-axis and q-axis inductance of PMSM are identified by high frequency injection method, and improved dead-time compensation is used to improve the accuracy of identified inductance. On this basis, a current predictive control algorithm is used to expand the current response bandwidth and enhance the performance of torque. By using the PDFF algorithm to realize motor speed control, speed regulator can be transformed easily to meet the various requirements. For applications that require high dynamic response of speed, a model tracking algorithm is proposed which calculates the optimal feedforward based on model. And the speed response can be improved distinctly by utilizing the method. Acceleration and deceleration method is used to identify the inertia of motor and load which is intended to estimate load torque. For applications with severe load disturbance, a disturbance feedback control is put forward which feedback the estimated load torque to enhance the ability of disturbance rejection. Finally, the experiments of parameter identification, frequency response of current and speed, and load disturbance experiment are accomplished, which verify previous theoretical derivation and analysis. Besides that, the work is summarized and the outlook is put forward.