| In order to protect the environment that, the automotive green technique has become the hot mankind relies on, nowadays issue of the world. Especially current petroleum resources face to dry up, so the research and development of the green automobile has become the main direction of the world. The motor driving system is the one of the automotive key techniques, so it is profound to solve this key technique.Hybrid electric vehicle (HEV), which combines the advantages of the conventional automobile and electric vehicle arises and becomes one of the most feasible ways to solve pollution and fuel problems. Integrated starter/generator (ISG) is a key technology of parallel hybrid electric vehicle. Automobiles with ISG having low fuel consumption and emission have become one of the world-famous advanced hybrid electric vehicles.The different types of HEV configurations can be classified into three basic kinds: series (SHEV), parallel configurations (PHEV), or a combination of both (PSHEV). ISG-based HEV is a typical kind of PHEV. The ISG system with motor not coaxial with the engine is also called B-ISG system, as the motor is connected to the engine crankshaft by belt drive. The technology of B-ISG is always used in mild hybrid vehicles. In the ISG system where the motor is directly mounted on the engine crankshaft, the motor can have greater power and can be used in moderate and heavy hybrid vehicles. Considering both performance and cost, we select the structure that the motor is mounted on the flywheel output end of diesel engine and then connected to transmission via a clutch. In order to decrease the energy loss in the circuit and the cost of the sysytem, the voltage of the ISG-based HEV is selected at 336 V. The high voltage of battery pack can bring many freedom to the system design. In this article,In the ISG-based hybrid electric system, the electricmachine should be able to work in states of electric drive or power generation. The motor drive system should provide an enough large starting moment, to meet the need of starting and ability of power-assisted. As well, the motor drive system should have efficiency as high as possible and also high reliability. In the hybrid electric power system, the classes of motor usually used mainly include direct current motor, the permanent magnet motor, the induction motor and the switched reluctance motor. After comparison of motors with different structures, the permanent magnet synchronous motor (PMSM) is selected as the electric machine used as the ISG motor. Then, the parameters of the ISG motor were selected with considering of both the performance and control objectives of the In the ISG-based hybrid electric vehicle.The control of ISG motor is a tough task as the motor has to rotate with the engine at the same speed. This thesis studies on vector control algorithm of ISG motor. The control system based on Motorola DSP type single chip microcomputer 568F8367 is developed. The inverter module are mainly composed of six insulated gatebipolar transistor (IGBT), and the space vector pulse width modulation is used to produced three phase alternating voltage, which directly drive the PMSM. The developed control system is tested on the ISG experiment platform, and the control algorithm is optimized using the experiment data. The experimental result proves that the performance indexes are meted.The vector control system much dependence on the parameters of PMSM, such as the rotor position, and complicated coordinate transformation is needed. They are problems to be solved. The direct torque control of PMSM is studied. In this control method, field orientation is not achieved by feedback, so the rotor position is unneeded, while fast and reliable torque response can be produced. A simulation model of direct torque control system is developed using the Matlab/Simulingk toolbox and the control performance is studied by simulation results. After analysis of field weakening operation in direct torque control system, an algorithm of field weakening control is proposed and also studied by simulation. The main defaults concerned with the traditional direct torque control system are the large torque ripple, poor performance of low speed region, inconstant switch frequency, etc. The reason of torque ripple is studied and refinement algorithms world wide are reviewed. Finally, the Future research direction is suggested.In consideration of credibility position sensors usually use the scheme of rotary transformer in hybrid electric vehicle (HEV) in which PMSM is adopted, but the two shaft ends of PMSM one is connected with clutch the other is connected with engine and the shaft diameter is relatively larger so disposal of rotary transformer is relatively difficult to hybrid electric vehicle (HEV) which adopts relatively high power PMSM(40KW mean power,80KW peak power) as ISG motor. The price of rotary transformer is relatively expensive and the special operation chip is needed and the price of the chip is expensive. The integrated cost is relatively expensive.This paper talked about Extented Kalman Filter scheme, direct computation scheme, model reference adaptive system scheme, armature current flux based adaptive full-order observer scheme and observer based on emf scheme and these schemes are adopted to compute rotor speed and rotor position in sensor less systems. The basis principle were given. The schemes were established in the environment of Matlab and the simulation results were given. The actual sensorless system adopted observer based on emf was realized and tested. The test data of the system was analyzed.This paper proposed a new scheme adopted hall sensor based on digital phase locked loop principle to test rotor position. This scheme cost little CUP resourse and this scheme was tested in actual systems.In the actual system scheme adopted hall sensor based on digital phase locked loop principle was realized and sensorless scheme adopted observer based on emf was realized. The actual system was tested and the output data was analyzed.Motor test system was characterized and the ISG motor integrated test, data collection, watch, parameter modification online software and hardware system for hybrid electric vehicle were realized. The system software and hardware were talked about systemically. The improvement of the system was proposed.Several problems worth deep sudied were proposed on the basis of sumerrization of the whole paper.
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