Permanent magnet generator

Abstract

The invention relates to a permanent magnet motor. The motor comprises a stator and a rotor. The rotor is provided with a gap arranged between a first permanent magnet and a third permanent magnet. The radial length of the first permanent magnet is larger than the radial length of the third permanent magnet. The length of the gap is smaller than the length of the third permanent magnet. The permanent magnet motor is relatively good in thermal conductivity, low in rotor temperature, small in leakage inductance, small in flux linkage harmonic wave, small in generator eddy current loss and smallin iron loss. Meanwhile, the rotor of the motor does not jitter, so that the service life of the motor is long.

Description

technical field [0001] The patent of the present invention relates to a permanent magnet generator, and high-strength permanent magnet materials used in generators and motors to make electrical equipment, especially permanent magnet materials in permanent magnet motors used in special engineering vehicles. Background technique [0002] As a material that provides energy, rare earth permanent magnet materials are widely used in generators, motors, computers, automobiles, military industry, medical facilities, power tools, office equipment, household appliances and other fields. With the development of science and technology, the demand for materials The performance requirements are getting higher and higher to meet the requirements of special fields such as high magnetic properties and high temperature, and to promote the progress of related application devices. [0003] A method for preparing rare earth permanent magnet materials has been disclosed in the prior art. The meth...

AI Technical Summary

Problems solved by technology

In the whole process, there are very high requirements for permanent magnet powder, hot pressing and heat deformation process, etc. Any step difference or temperature change may have a crucial impact on the performance of the final product, resulting in the occurrence of magnetic properties. Defects such as large changes and uneven magnetic fields are used in situations where the uneven magnetic field in the motor causes large vibration, high noise, and failure to operate normally.

At the same time, it cannot meet the problem of the reduction of the magnetic performance of the motor under high temperature and long-term operation.

Chinese patent CN104143402A proposes hot pressing and thermal deformation; CN102496437A proposes to improve the remanence and magnetic energy product of permanent magnet materials; the motor operating performance disclosed in Chinese patent document CN104078179A is not high

It is common for permanent magnet materials in motors to affect the performance of motors due to magnetic changes caused by high temperatures, especially in linear motors and permanent magnet synchronous motors, which will cause low efficiency, large noise, and large thrust fluctuations, which seriously affect torque stability. Therefore, it is necessary to improve the structure of the motor and the control circuit in the motor so that the heat generated during the operation of the motor can overcome the influence of the heat generated by the long-term and high-power output on the magnetic properties of the permanent magnet material, causing unstable changes in the performance of the motor, and even loss of magnetism. Great impact on motors and generators

[0007] In permanent magnet motors, slight changes in the motor structure provide different flux paths, which can affect the change of magnetic flux and generate more magnetic losses, especially in the case of long-term full-load operation or motor stalling, high temperature can make The magnet structure of the permanent magnet changes, resulting in loss of magnetism or changes in the polarization of the residual magnetism, causing unstable operation of the motor, or vibration, noise, etc.

In the control of permanent magnet motors, since most of the set control methods are fixed, this design can easily lead to the patterning of motor control, and cannot adapt to changes in motor performance caused by magnetic changes, which can easily lead to control failures in the load. Excessive or inappropriate issues

Similarly, in the design of multi-phase fault-tolerant permanent magnet motors in the prior art, fractional slot concentrated windings are used, and the number of harmonics decreases, but the amplitude value becomes larger, resulting in greater iron loss of the motor; it cannot better meet the fault tolerance of permanent magnet motors Improve the performance of permanent magnet motors while meeting the requirements

In the existing PWM algorithm of multi-phase permanent magnet motor, a matrix transformation method is proposed to adapt to the change of permanent magnet magnetism in the motor. Inductance, permanent magnet flux harmonics and other factors, so large current fluctuations have an impact on the life of permanent magnet motor control devices, etc., and cause permanent magnet motors to run unstable

Especially in large-scale engineering vehicles with harsh construction conditions, large temperature differences, full-load operation, and extreme weather conditions such as dusty and humid conditions, excessive heating of the rotor due to eddy current loss and harmonic loss of magnetic steel, temperature rise Increase, in actual operation, it can actually rise to nearly 130 degrees. In order to ensure the continuity of construction, it is usually necessary to carry a motor with stable operation. The permanent magnet motor is usually unable to meet the needs of the project due to the influence of the above conditions, and this application It is to solve the above problems and provide permanent magnet motors with stable operation and long service life for engineering vehicles, etc.

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