Design And Research On High Temperature Superconducting Generator Excitation System

Along with the discovery of high temperature superconducting materials at the beginning of 1990's,the research of high temperature superconducting machine has made substantial progresses.As a special motor,high temperature superconducting(HTS)machine owns advantages such as lighter,smaller,higher efficiency,lower noise,easier in maintaining,easier operation and larger capacity of single limit.But the current research on HTS machine is less,development of supporting system of motor development is very slow,especially for high temperature superconducting motor excitation system.The current study of HTS machine excitation system has several difficulties as the following:1.The design and operation data of the HTS machine is still classified as confidential,research in the working state of the motor ontology is difficult.2.The actual design problems also exist in corresponding excitation system,due to the unecific design structure of the HTS machine,the hardware design of excitation system can not be targetedIn view of the characteristics of HTS machine,this dissertation carried out the design and research work of the excitation system of HTS machine,the work content mainly includes the following several aspects:Firstly,by overviewing and analyzing related literature of domesic and foreign,the structure and characteristic of HTS machine has been cleared,based on which we built the mathematical model of HTS machine and verified the feasibility of the model by simulation.Secondly,according to the characteristic of HTS machine and analysis of those related data,this dissertation puts forward the designation of HTS machine's digital excitation system.Carried on the design of hardware for excitation system according to the module of the digital excitation system,then accomplished chip selection and design of peripheral circuit of the digital excitation regulator,finishing software design soon after.Thirdly,put forward the design of controller for excitation system of high temperature superconducting machine.According to the design requirements of high temperature superconducting motor excitation system and job characteristics,this dissertation puts forward three kinds of controller,respectively,PID,fuzzy PID and variable universe fuzzy PID control.The PID control used teminal voltage error as the input and fuzzy PID control used teminal voltage error and error changing rate as input,excitation voltage as the output value of the control object to control the excitation system.Finally,consracting the simulation model of the controller above and made some adjustment based on the HTS machine simulink model,then simulated the new model under two cases:in normal condition and in fault condition.Through out the response curves obtained through simulation of the three kinds of controller,came out the conclusion that the variable universe fuzzy PID control has the best control effect.