Research On High-power BLDC Controller

Environmental pollution and energy shortage have become increasingly seriousin today’s society, and there is no doubt of that the electric car is a better solution tosolve these problems, and also to a large extent eases the pressure of oil resourcescrisis the transport. the electric bicycle, electric motorcycle and electro-mobile have arapid development in recent years, which fall in the electric car.Initially, brush DCmotor, as the power system of the kind of transport, but there are many defects afterworking long.In recent decades, as the development of the new permanent magnetmaterials, integrated circuits, power electronics and control algorithms, especially theapplication of power switching devices in the driver circuit is more and more mature.Brush motor has gradually replaced by brushless DC motor and become a dominantforce in the power system. The control technology of the brushless DC motordetermines the security and stability of the electric car system.The control object of the high-power brushless DC motor control system isbrushless DC motor.Firstly, this paper introduces the structure and working principleof the brushless DC motor and after comparison find that it is more suitable thanbrush DC motor as a dynamic system, and then establish the differential equations andtransfer function model. It contributes to familiar with the operating characteristics ofthe brushless DC motor in theory. Secondly, design the overall structure and thehardware circuit of the high-power brushless DC motor control system. The overallstructure contributes to a comprehensive understanding of the functionality of thecontroller and the focus of the controller. The power supply circuit is the premise ofthe system; the drive circuit is the basis of the controller, the current acquisitioncircuit to protect the safety of the controller, while the other functional circuitdetermines the overall level of the controller. If the hardware is the skeleton of thesystem, the software is blood. The quality of software code determines the securityand stability of the control system.The software have to response each sub-task intime, and have protection when the controller is error. Finally, the samples have beenfully tested. Include the overall data of the dynamometer test, under different softwarestructure data test and the oscilloscope on the current waveform acquisition. And thenrigorous analysis of the data, obtained further modifications to the software in order to achieve the desired objectives.According to the data obtained by the actual test and simulation confirmed thedesign of the controller of the present subject is basically reach the standard of theproduct on the market. Good performance in the current control and system efficiency,and with EABS, automatic cruise, quiet startup, anti-theft alarm and other functions.