Research On Controller System Of Four Phase Permanent Magnet Brushless DC Motor For Cooling Fan

With the development of automobile industry and electronic technology,automotive electronics has become an irreversible trend,each control unit has been gradually evolved into electronic information control by mechanical control and relay control.As an engine cooling system,has a very high status in the vehicle configuration and power system,the research of this subject has strong practical value.With the rise and development of automation,more and more widely used in the field of motor,has gradually penetrated into all walks of life,the control unit of the traditional three-phase motor has high cost,high torque ripple and low control precision,which has not been improved for many years.But the four phase brushless DC motor just makes up for this shortcoming.In this paper,the research work of the four phase brushless DC motor is carried out with the vehicle engine cooling fan as the carrier.In this paper,the research focus on four phase motor without position sensor,torque ripple,dual mode control and other technologies are studied,and the direction for further research is pointed out.In this paper,the following four aspects to carry out the four phase brushless DC motor control system:(1)based on the traditional three-phase motor control technology,starting from the motor working principle and control principle,based on the first principle of learning after the rapid solution is used to analyze the working principle of the four phase DC brushless motor,deduces the four phase DC brushless motor control principle.And the use of traditional motor related formulas,the use of Simulink module to build a four phase brushless DC motor mathematical model,and modeling and simulation.(2)analysis of the application environment and the function of the motor controller,create the hardware design requirements,and focus on the needs of the analysis,research related solutions,design hardware schematic.The key issues such as the use of NTC,the placement of sensor placement and the selection of key chips have also been studied.Finally,the design and system integration of the control drive circuit,protection circuit and detection circuit are completed,and the system is integrated,and a printing plate is drawn.(3)analyzes the vehicle software requirements and design requirements,the software control flow chart,and each module of the system architecture of algorithm,especially the software protection strategy and PI closed-loop control,according to the flow chart of software architecture in the integrated development environment to write software program,the main program modules,including the main program the speed of the current interrupt subroutine,subroutine.Design a set of software system and in the FreeMaster environment on the software to do online debugging.(4)build motor and controller environment,Shaoxie software program,the function of each software one by one test,found the problems of the software and hardware and timely solve,then do the whole joint debugging,but also give full verification of hardware system,the waveform analysis and give the system further optimization,finally get a perfect the control system in the trial and improvement.