Characteristic Analysis Of Permanent Magnet Synchronous Motor Of Electric Bulldozer

With the development of electric transmission technology in engineering machinery,permanent magnet synchronous motor(PMSM)has become popular in electric transmission engineering machinery.Due to the wide application of permanent magnet synchronous motor used in passenger cars and commercial vehicles,more demand for the output characteristic of motor vehicle and engineering machinery has a larger difference,in order to solve this problem,based on the electric drive bulldozer as the research object,in order to improve the application of permanent magnet synchronous motor in the electric drive bulldozer,for the purpose of the study as follows:Starting from the analysis of the structure and working characteristics of the electric drive system of the electric bulldozer,the dynamic characteristics of the bulldozer were studied in depth and the dynamic model was established to determine the performance requirements of the vehicle.Based on the comparison and analysis of the output characteristics of the traditional engine and the driving motor,the importance of the matching design of the motor performance parameters is expounded,starting from the influence of the performance parameters of the permanent magnet synchronous motor of the electric bulldozer on the dynamic performance of the vehicle.The performance parameter matching constraint model was established,and the matching methods of diesel engine and permanent magnet synchronous generator,diesel power system and driving motor,and driving motor and external load were designed.According to the matched driving motor performance parameters,the design of motor rotor structure is carried out.The working principle of permanent magnet synchronous motor was studied,and the steady-state mathematical model of the motor under the alternating and direct axis was established.It was concluded that the greater the inductance difference of the alternating and direct axis was,the higher the output torque and efficiency of the motor,and the more the high efficiency area covered the middle-low speed area under the condition of constant input.Proposed increase the motor torque density,improve efficiency,and low speed in high efficient area coverage area and reduce the dosage of permanent magnets,optimal design target,the theoretical analysis of magnetic barrier thickness,magnetic barrier layer,the outer magnetic bridge insulation thickness,the thickness of the permanent magnet magnetic bridge between,air-gap length to the direct axis inductance difference size influence mechanism and simulation,determine the optimal value of each structural parameter range,drive motor comprehensive optimization orthogonal experiment design,optimization design,eventually get motor structure Maxwell2 D motor model and characteristics of simulation analysis.Finally,based on AMEsim,the electric bulldozer model was established,and the operating condition simulation analysis was carried out to verify the performance parameter matching design of PMSM and the optimization design results of PMSM.The results show that increasing the inductance difference of the ac axis can obviously improve the output characteristics of the electric bulldozer motor.After the optimization design,the inductance difference of the ac and dc axis of the motor was increased by 50.7%,the output torque was increased by 6.1%,the consumption of permanent magnet was reduced by 25.7%,and the efficiency was improved and extended to the medium-low speed region.The minimum speed in the coverage area of the 98.6% efficient zone was 1500r/min.The driving motor of the electric bulldozer works stably in the high-efficiency region of 98.2% to 98.6% under the condition of soil shoveling,and there is still room for further optimization under the condition of reversing.