Design And Experimental Study Of Governor For Motor Based On Eddy Current Drive Principle

With the rapid economic development,high consumption of energy has hindered the economic development in China.Environmental protection and energy-saving has become the national strategy.The eddy current governor for motor with characteristics of energy-saving and environmental protection,non-touch transmission and shock absorbing is a new type speed regulation device based on eddy current drive principle,it can realize soft start,overload protection of motors and adjust to the load speed and torque online.The mainstream governor at present,which can be divided into disk and cylindrical in structure,is the permanent magnet eddy current governor.In this paper,the eddy current governor setting as the research object,the electromagnetic energy conversion and transfer as the core,the model of drive torque as basic,the issues are studied systematically which include the model of electromagnetic field and temperature field and the key energy-saving problem of eddy current speed regulation is solved.The main contents of this paper are organized as follow:Chapter one,the background and significance of motor speed regulation technology are summarized and the existing problems and deficiencies of the current motor speed regulation technology are analyzed,then discusses the advantages of the motor speed governor based on eddy current drive,introduces the research status at home and abroad,and discusses the relationship between the power and the driving torque of the eddy current governor.Chapter two,the structure and working principle of permanent magnet eddy current governor will be introduced,a novel self-excited eddy current governor with advantages of high reliability,simple structure and easy control will be manufactured then this paper discusses the advantages in speed regulation of the novel self-excited eddy current governor by comparing the speed regulating mechanism of these two devises.Chapter three,the permanent magnet eddy current governor and the novel selfexcited eddy current governor were analyzed by using equivalent magnetic circuit method,and the electromagnetic field was analyzed by using numerical simulation method.This paper emphatically presents the design methods of generation system in the novel self-excited eddy current governor and using finite element simulation to analyze generation system,studied the electromagnetic matching characteristics of transmission system and generation system.Chapter four,on the basis of analyzing eddy current loss for disk permanent magnet eddy current governor.In combination with the empirical formula,heat dissipation coefficient and thermal conductivity of the disk permanent magnet eddy current governor are introduced.The steady state of temperature rise in a working condition was analyzed by ANSYS,and the temperature distribution in parts were obtained.Chapter five,the simulation test of disk permanent magnet eddy current governor are done,through testing the relationship between drive torque and rotation difference,gap length and temperature,then the transmission characteristics and temperature increase characteristics of prototype are studied,and compared the simulation data and the experimental data,the results show that the simulation data agree well with the experimental data.