Linear motion structure of permanent magnet synchronous linear motor

Abstract

The invention discloses a linear motion structure of a permanent magnet synchronous linear motor. The linear motion structure comprises a secondary pole and a primary pole. The secondary pole comprises a secondary yoke plate and a permanent magnet array. The primary pole comprises a primary iron core and a primary winding. The permanent magnet array comprises a front permanent magnet set, a middle permanent magnet set and a back permanent magnet set which are successively arranged in a front-and-back direction. The middle permanent magnet set integrally shifted leftwards or rightwards relative to the front permanent magnet set, and furthermore the shifting distance is tau/2. The widths of the front permanent magnet and the back permanent magnet in the front-and-back direction are m respectively, and the width l of the middle permanent magnet in the front-and-back direction is 2m. According to the linear motion structure, the magnetic pole of the middle permanent magnet is shifted by tau/2 relative to the front permanent magnet, thereby realizing a phase difference 90 DEG between thrust fluctuations which are generated by one end of the motor, realizing mutual offset of the thrust fluctuations, reducing an end effect of the linear motor and settling a thrust fluctuation problem caused by normal force fluctuations. Furthermore the linear motion structure has advantages of simple manufacture process and high convenience in batch production.

Description

technical field [0001] The invention belongs to the field of permanent magnet synchronous motors, and more specifically relates to a linear motion mechanism of a permanent magnet synchronous linear motor. Background technique [0002] Due to the disconnection of the armature core of the permanent magnet synchronous linear motor and the discontinuity of the end arrangement of the stator winding, it has a characteristic problem different from that of the rotary motor, that is, the end effect unique to the linear motor. It will increase the additional loss of the linear motor, reduce the efficiency of the linear motor, and especially cause the thrust fluctuation of the linear motor. Thrust fluctuation is one of the main reasons affecting the application of linear motors, because thrust fluctuation will generate mechanical vibration and noise, and may cause resonance when running at low speed, and will seriously deteriorate servo performance, such as positioning accuracy. Theor...

AI Technical Summary

Problems solved by technology

Thrust fluctuation is one of the main reasons affecting the application of linear motors, because thrust fluctuation will generate mechanical vibration and noise, and may cause resonance at low speed operation, and will seriously deteriorate servo performance, such as positioning accuracy, etc.

Theoretically, it can be reduced by choosing a reasonable base groove fit, primary chute, secondary permanent magnet oblique pole, optimizing the width of the permanent magnet and the shape of the tooth groove, but these traditional methods are not obvious for weakening the end effect

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