Research On The Overall Working Efficiency Of Brushless DC Motor And Driver

Brushless DC motor has been widely used for its advantages of high power density,long life,high reliability and good stability.In today's society,where low-carbon travel,energy conservation and energy efficiency are being promoted,electric vehicles,electric motorcycles,and three-wheeled passenger vehicles are increasingly moving towards the consumer market.Brushless DC motor(BLDCM)as the driving power of electric vehicle(EV)has become a hot topic in recent years.The normal operation of brushless DC motor must be completed by electronic commutation of the driver,brushless DC motor and driver can be said to be inseparable.The brushless DC motor has the most efficient running state and the driver has the most efficient running state.However,a large number of experimental data show that the brushless DC motor and the driver are working in the most efficient state,and their overall operating efficiency is not near the highest point.Especially the brushless DC motor is used in some fields where the load changes with the external environmental factors,such as electric vehicle,electric motorcycle,human three-wheeled horizontal car and so on.In these cases,the output power of the brushless DC motor and the circuit parameters of the driver will change continuously due to the change of the driving conditions.And most importantly,electric vehicles,electric motorcycles,three-wheeled passenger vehicles are all powered by on-board batteries,with very limited energy.If the whole operation efficiency of brushless DC motor and driver can be improved,the range of battery car can be increased to a great extent,and the new energy battery car will be provided with more development space.At the same time,it will greatly reduce the environmental pollution caused by traditional fuel vehicles,change the way people travel,and make a great contribution to energy saving and emission reduction.In this paper,the coordination between brushless DC motor and driver is not optimal.The disadvantages and shortcomings of the traditional brushless DC motor drive mode are analyzed.This paper presents a control method which can adaptively change the working state and output mode of the driver according to the load change of the external environment and improve the overall operating efficiency of the brushless DC motor and the driver.Further reduce the loss of energy and improve the efficiency of energy.The experimental scheme is demonstrated by mathematical modeling,theoretical analysis andthe way of data measurement based on the experimental platform.In this paper,STM32F407ZGT6 chip is used as microprocessor,which is a 32-bit microprocessor with low power consumption and has strong data processing ability.Labview,a graphical virtual instrument developed by the National instrument Company of the United States,is used as the upper computer software.As an intermediate connecting bridge,the data acquisition card displays and analyzes some electrical parameters in the operation process of brushless DC motor and driver on the computer to verify the feasibility of the experimental scheme.Finally,the experimental data show that compared with the efficiency curve without any control optimization algorithm,the overall operation efficiency of brushless DC motor and driver is improved by 4 percentage points,and can run near the highest point of efficiency continuously,which achieves the ideal control effect and accords with the expected goal.