Optimization Design Based On SRD Electric Wheel Control System

With crisis of energy resources and increased environmental pollution, the development of electric vehicles has become inevitable in the future of the automo-bile industry. The electric vehicles use electric energy as power. The electric vehicles have the advantage of clean, no contaminating, and advanced energy efficiency. The electric drive system is the heart of electric vehicles. Compared with the other electric vehicle drive systems, the wheel hub motor drive structure is compact. Through inte-grating power system, transmission device and brake link systematic in the wheel, the mechanical structure of vehicle is simplified various, the control is very flexible.The switched reluctance motor has the characteristics of simple structure, high re-liability, great torque and small startup current. SRM has broad prospects in the field of electric vehicles. The main work in this thesis is to complete optimization design of the SRD electric wheel control system, and focused on the design of the power converter. The power converter is linked to the motor and vehicle power in the electric wheel sys-tem, has a vital effect.Firstly, this thesis introduces the characteristics of the wheel hub motor drive and the foreign and domestic development situation of electric wheel system, analyzes the exterior rotor switched reluctance motor working principle, including the establishment of linear mode and the main control modes of motor. The asymmetric half bridge to-pology is chosen as the power converter’s main circuit. The type of IGBT is chosen, the thesis designs IGBT drive circuit and buffer circuit.In addition, this thesis estimates the power loss of power of power converter main circuit, designs the water cooling, uses three-dimensional mechanical design software SolidWorks to design the power converter control box, tests its thermal reliability by using thermal simulation software FloTHERM.The thesis also designs switched power based on the principle of single-ended fly-back converter topology, whose voltage input range from200V to400V and output power is74.5W. The switched power supplies power for the whole electric wheel. Fi-nally the experimental results verify the switched power performance and the feasibility of power converter design.