Speed Sensorless Vector Control Of High Voltage Frequency Converter

High voltage motor has the characteristics of big power,big inertia,it is an important category of the motor,which is used in mechanical industry,petroleum chemical industry,power plants and other industrial special occasions.And the H bridge cascade high voltage inverter,as the high voltage motor control device,which is responsible for implementing the high performance frequency conversion timing control,has a broad application prospect,and become a research hotspot in recent years.Combined with project practice,this paper mainly introduces speed sensorless vector control of research based on the H bridge cascaded high voltage frequency converter,and puts forward an improved high voltage induction motor parameter off-line identification method,at the same time summarizes the research's various performance,believing that we can lay a foundation for further research in the future.Compared with the general platform for the two level low voltage inverter,in the H bridge cascaded high voltage inverter output voltage's reconstruction is not easy to achieve,and the output voltage is higher,the rotational inertia of the high voltage motor is bigger,these are the difficulties of the parameters identification and the high performance frequency conversion timing control.According to the above analysis,this paper firstly introduces the related important background knowledge of topic,including H bridge cascaded high voltage inverter topologies,modulation strategies,control difficulties and research status.Then this paper puts forward an improved high voltage motor parameter off-line identification method,analyzes the current status of the application of the induction motor parameter off-line identification technology,analyzes the advantages and disadvantages of various implementation methods,then reanalysis the equivalent circuit of induction motor and introduces this method,this article finally through MATLAB simulation and experimental validation summarizes the method.Then,this article focuses on the study of speed sensorless vector control of high voltage frequency converter.It describes induction motor rotor speed and flux linkage angle estimation principle based on the method of back EMF,introduces in detail the engineering design method of current regulator and speed regulator in the vector control,and introduces the latest complex vector current regulator.About the high voltage inverter hardware experiment platform,this paper analyzes based on the experiment platform the speed sensorless vector control's implementation difficulties,solutions and problems.Finally,the MATLAB simulation and experiments verify the theoretical feasibility speed sensorless vector control of the experimental platform of high voltage frequency converter,and analyze the steady-state and dynamic performance of frequency conversion timing control by the experimental data.