The Research Of Sensorless Vector Control System Based On Direct Field Oriented

Asynchronous motor has been widely used in industrial application with its low cost,simple structure,easy maintenance,etc. The emergence of vector control improve theperformance of Asynchronous motor, it makes the asynchronous motor speed controlsystem with high resolution speed sensor have the comparable high performance to theDC motor. But the use of speed sensor broke the original advantages. In this case, theresearch and application of sensorless vector control appear.This thesis theoretically expounds the idea of vector control,the method of equivalentconversion and the theory of rotor field-oriented control. It also constructs a sensorlessvector control system based on direct field-oriented. The system adopt a proposedVoltage-Current model to construct the rotor flux observer. The proposed model is basedon a used Voltage-Current model and improves after doing the research on its principleand parameters. Compared to original model, the proposed model has a simple structureand applys to wider speed range. The sensorless vector control system adopt a open-loopcalculation method to estimate speed. The calculation has a clear physical meaning and iseasy to implement.This thesis constructs the sensorless vector control system on saber simulationplatform and does research on three aspects. The first is on modules. It focuses on theeffect of flux observing when the pure integral exist or stator resistance changes. Thesecond is on parameters. It focuses on the effect of flux observer when the parameterschange. The third is focus on the performance of the system. It does some analysis on thesensitivity to the parameters of motor.After the simulation, a physical platform based on TMS320F2810DSP is constructed.This thesis also does research on the physical platform on three aspects. It focuses on theeffect of flux observer, the operation of the system and the sensitivity to the parameters ofmotor. The results of physical experiment and simulation research verify the feasibility ofthe flux observer and the sensorless vector system, also present the influence ofparameters of flux observer and motor.