Parameter Calculation And Electromagnetice Force Analysis Of The Low-Voltage High-Power Multi-Branch Permanent Magnet Synchronous Motor

Usually, conventional large mechanical equipment is driven by induction motor of high-voltage, and using high-voltage converter in the situation needing frequency conversion control. The primary problem of this way is that the high-voltage converter output waveform is fluctuation and it could produce lots of harmonic pollution which impact power grid and motor. And the cost of high-voltage converter is too much. The efficiency and power factor of induction motor are closely related to the load rate and decreasing obviously when the load rate has dropped. To solve the above problem, low-voltage high-power permanent magnet synchronous motor(LHMB-PMSM) is presented. The main work of this paper is as follows:By analyzing the characteristics of the low-voltage high-power multi-branch permanent magnet synchronous motor and the design theory of permanent magnet synchronous motor, the relevant mathematical expressions of the low-voltage high-power multi-branch permanent magnet synchronous motor are given. Introduced its stator windings and the structural characteristics of terminal blocks.The running operation of the motor has decomposed into equivalent d-axis state and the equivalent q-axis state. The air-gap flux density can be acquired by the Ansoft software. Using Matlab software, the fundamental flux density is obtained by Fourier decomposition. By the phase diagram of permanent magnet synchronous motor, the armature reaction reactance can be obtained. The calculated and measured values were compared.Finally, use of Ansoft12.0 build the prototype of 30kW,8 poles,8 branches 3D model and calculate it. By post-processing, the magnetic flux density distribution of the stator lamination and stator end are obtained. Analyzing the electromagnetic force of stator end windings. Through numerical simulation, we can give the location where maximum electromagnetic force occurs.