Magnetic bush, motor rotor, motor

Abstract

The invention provides a magnetic bush, an electric machine rotor and an electric machine. The magnetic tile includes a back EMF fundamental wave generating section and a back EMF harmonic wave generating section, the back EMF harmonic wave generating section being located outside the radial direction of the back EMF fundamental wave generating section. According to the invention, a magnetic bush,an electric machine rotor and an electric machine can realize noise reduction effect by superposing harmonic components in the magnetic bush and synthesizing with a current fundamental wave to cancelthe toothed groove torque.

Description

technical field [0001] The invention belongs to the technical field of motor manufacturing, and in particular relates to a magnetic tile, a motor rotor and a motor. Background technique [0002] At present, most DC motors are driven by sine waves. Through sine drive, the output torque of the three-phase synthesis can theoretically achieve no fluctuation. The inherent existence of the cogging torque, after the cogging torque is superimposed on the output torque, will produce torque fluctuations. The industry often uses methods such as adding auxiliary slots, oblique poles, and inclined slots to reduce the cogging torque, but the implementation process is relatively cumbersome. . [0003] A new method for reducing the cogging torque is proposed. By changing the output waveform of the back EMF of the motor, or superimposing the harmonic component in the current, the ripple torque generated by the back EMF and the current is used to counteract the cogging torque in the opposite...

AI Technical Summary

Problems solved by technology

[0004] After research, it is found that the theoretical waveform functions of the three-phase sinusoidal back EMF are U×sin(wt), U×sin(wt-2π / 3), U×sin(wt+2π / 3); and the three-phase sinusoidal winding current Theoretical waveform functions are I×sin(wt), I×sin(wt-2π / 3), I×sin(wt+2π / 3), and the final synthetic output torque T=9.55×P / n=9.55×U ×I×{sin(wt)×sin(wt)+sin(wt-2π / 3)×sin(wt-2π / 3)+sin(wt+2π / 3)×sin(wt+2π / 3)} / n=9.55×1.5×U×I, and corresponding to any speed of the motor, the voltage peak value U and current peak value I are theoretically constant, so it can be seen that the combined output torque T is independent of the motor speed (frequency) constant value, however, when the cogging torque is superimposed, there will be fluctuations in the torque

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