| Synchronous reluctance motor has the advantages of high precision,high power factor,high efficiency and low cost,so it is regarded as a substitute for permanent magnet synchronous motor and asynchronous motor in the application of the ideal motor pump,blower,air compressor and other fields in recent years has been regarded by experts and scholars.Because the motor in the application of driving pump and fan in a complicated environment and under large changes in load motor problems,so how to solve in the harsh environment due to introduction of sensor reliability and cost limitation system brings and how to improve the motor starting torque in the control algorithm and load capacity problem is the key to this research.First,based on the analysis of the mathematical model of the synchronous reluctance motor,we introduce the direct torque control method of the synchronous reluctance motor.In order to solve the problem of reducing the cost and reliability of sensors,this subject adopts the method of stator flux model based on position / velocity estimation;at the same time,we designed the integral separation PI controller is introduced to control the structure of magnetic link / torque loop as the inner loop and the speed loop as the outer ring;in order to improve the motor starting torque and load capacity,we propose a torque estimation and compensation method based on instantaneous power theory,the eventual establishment of a synchronous reluctance motor direct torque the position sensor control system.Secondly,in order to verify the correctness of the algorithm,according to the principle of direct torque control system,we determine the system principle diagram,according to the mathematical model and control method of the motor before,we set up in the Matlab/Simulik simulation model of direct torque control system of the position sensor,at the same time,we simulate the system model,from starting characteristics,dynamic characteristics and anti load characteristics.According to the simulation results,when the motor speed is 1500 rpm and 3.6 load is started,the actual speed up to 192 ms is steady,and the speed of steady process is about 0.1%.When the given speed cycle is 1.5s,speed of 1500 rpm to 750 rpm square wave signal,motor in 1500 rpm steady state operation,the actual speed and speed estimation error between-15rpm~12rpm,and in 750 rpm steady state operation,the actual speed and speed estimation error in-10rpm~7rpm.In the following simulation speed,it still has a good performance in a given 5rad/s follow the sine wave,the tracking error is lower than 75rpm;in the simulation of restraining load variation,when the steady speed is fixed at fixed speed,the sudden increase of rated load and speed drop to 1350 rpm only need 60 ms to restore to steady state,which has good load disturbance performance.Finally,we set up the test platform,which is composed of upper computer,driver,voltage regulator,magnetic powder clutch,magnetic powder brake,torque speed meter and synchronous reluctance motor.The corresponding algorithm software is developed under the CCS development environment,including bus voltage overvoltage / undervoltage protection,current overcurrent protection,current analog to digital conversion program,PWM algorithm program,integral separation PI program,speed estimation program and direct torque control program.Based on this platform,we have tested the no-load characteristics and load characteristics of the synchronous reluctance motorThe experimental results show that when the given speed to the rated speed,the load is 0 N ?m(no load),the estimated velocity fluctuation is 0.56%;and when the given speed to the rated speed,the load is 3.6 N ?m(rated load),the estimated velocity fluctuation is 1.00%,so we can prove that the control method proposed in this paper has strong carrying capacity. |
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