Research On Control Strategy Of Permanent Magnet Synchronous Motor For Belt Conveyor

With the development of our country Carbon peak and Carbon neutralization orderly advancement of the target,the development and progress of coal industry plays an important role in the development of green energy and industrial upgrading in China.As the main material transportation equipment in the coal industry,belt conveyor plays an important role in the innovation and development of the coal industry.However,the belt conveyor system driven by asynchronous motor has the problems of poor low-speed performance,high energy consumption and low mechanical efficiency.In order to the conveyor system has better speed regulation performance and high efficiency and safe operation performance.The belt conveyor system driven by permanent magnet synchronous motor was studied.First of all,through the comparative study of the driving modes of belt conveyor,the driving mode of permanent magnet synchronous motor directly driving the drum was determined,and the necessity of selecting permanent magnet synchronous motor as driving motor was analyzed in detail from the operation characteristics of belt conveyor and the requirements for driving device.However,due to the problems of low-speed operation of permanent magnet synchronous motor,the speed regulation system of belt conveyor was optimized from the perspective of drive system control.At the same time,by comparing and analyzing the characteristics of the main control strategies,and combined with the operating conditions of the belt conveyor,the direct torque control strategy was selected.But,when the permanent magnet synchronous motor runs at low speed,the traditional direct torque control method has some problems,such as poor speed regulation performance,inaccurate rotor position estimation and so on.In order to solve these problems,the stator resistance tracker was added based on the direct torque control mode of space vector pulse width modulation,and the SVPWM-DTC control speed regulation system with stator resistance tracking was established.Afterwards,in order to further improve the low-speed performance and anti-interference performance of the direct torque control system,the advantage of SVPWM to synthesize any space voltage vector and the good anti-interference character of high order sliding mode ware used.The discontinuous sgn(s)function in Super-twisting sliding mode control theory was replaced by the continuous sat(s)function,which ware applied to the controller of speed,torque and flux linkage.At the same time,a sliding mode observer based on phase-locked loop was designed to accurately obtain the information of rotor position and speed,and the direct torque control speed regulation system based on super-twisting sliding mode control was established.Finally,the SVPWM-DTC control speed regulation system with stator resistance tracking and super-twisting sliding mode control direct torque control speed regulation system ware built for simulation comparison and analysis in Matlab/Simulink.At the same time,the experimental platform of speed regulation system was built for experimental verification.The results show that,compared with the SVPWM-DTC control speed regulation system with stator resistance tracking,the direct torque control speed control system based on super-twisting sliding mode control has good speed regulation performance and accurate control performance.