Halbach array parallel rotor composite excitation brushless synchronous motor

Abstract

The invention relates to a Halbach array parallel rotor composite excitation brushless synchronous motor, which comprises a rotor and a stator for accommodating the rotor, wherein the stator comprises a magnetic groove sleeve, an annular exciting winding and the like; the magnetic groove sleeve is fixed on a motor end cover through bolts and is not contacted with the rotor; and the annular exciting winding is fixed at the groove of the magnetic groove sleeve. The rotor consists of a rotating shaft and a Halbach rotor and an electric excitation rotor which are arranged on the rotating shaft in parallel, and the Halbach rotor comprises a non-magnetic rotor supported by the rotating shaft and a Halbach array permanent magnet arranged on the surface of the non-magnetic rotor; the electric excitation rotor comprises a claw pole structure connected with the rotating shaft; and the Halbach rotor is separated from the electric excitation rotor by a separating magnetic ring formed by air gaps. The brushless synchronous motor can reduce the eddy current loss of the rotor, enlarge the adjustable range of a magnetic field and improve the power density of the motor, and has the advantages of high reliability and good energy-saving effect.

Description

Technical field [0001] The invention relates to an AC synchronous motor, in particular to a hybrid excitation brushless synchronous motor. Background technique [0002] Halbach array is a novel magnet arrangement method proposed by American scholar Klaus. Halbach for the structure of permanent magnets. The synthetic magnetic field of the rotor permanent magnet in the Halbach array is as attached figure 1 As shown, the air gap magnetic field presents a unique distribution, which is a unilateral magnetic field, and the proper magnetizing direction can make the air gap magnetic flux of the motor obtain a better sinusoid. The motor using the Halbach array can well control the iron loss when running at high speed, greatly improving the efficiency and power density of the motor; and in the Halbach motor, due to the high degree of sinusoidal distribution of the air gap magnetic field, the harmonic content is small Therefore, the stator and rotor do not need to use skew slots to weaken ...

AI Technical Summary

Problems solved by technology

Therefore, at low-speed operation, the reluctance part basically does not generate torque, resulting in a lower motor torque density, while at high-speed "weakening" operation, the magnetic flux of the permanent magnet section remains basically unchanged, and the reluctance section The magnetic flux increases with the increase of "weakening magnetic field", which leads to the increase of ferromagnetic loss with the geometric progression of speed, and the permanent magnet is directly exposed under the armature, which is easy to cause irreversible demagnetization

[0007] In a nutshell, parallel rotor hybrid excitation synchronous motors or permanent magnets in the prior art adopt traditional radial magnetization methods. Compared with Halbach motors, it is difficult to form ideal sine wave air gap flux and unilateral magnetic field. The permanent magnet rotor part needs to use the iron core to provide the magnetic circuit. The weight of the motor is large and the eddy current of the rotor is large during high-speed operation, which reduces the power density of the motor; or the magnetic field of the motor is adjustable, but the effective part of the Halbach magnet is small. The power provided by the Halbach magnet is small, and a large excitation current is required during normal operation to meet the stability of the output voltage, which undoubtedly increases the electric excitation power and excitation time constant; or the electric excitation part uses brushes and slip rings , which reduces the reliability of the motor

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