Starting structure set and method of asynchronous starting permanent-magnet synchronous motor

Abstract

A starting set and method of an asynchronous starting permanent-magnet synchronous motor comprises an asynchronous starting permanent-magnet synchronous motor main body and a combined control system thereof and is characterized in that two groups of independent windings are arranged between phases of the asynchronous starting permanent-magnet synchronous motor and are led out by nine leading-out lines, a winding combination structure of the asynchronous starting permanent-magnet synchronous motor is changed under the setting of a combined structure of the control system, low-current starting stable speed rising is achieved by a three-step starting structure mode, the starting and the running are both in star-like winding connection method, the high-efficiency performance of the asynchronous starting permanent-magnet synchronous motor is ensured, and a demagnetization phenomenon of a permanent-magnet material caused by impact of a large current during instant starting of the asynchronous starting permanent-magnet synchronous motor is effectively prevented.

Description

technical field [0001] The invention relates to a starting structure setting and method of an asynchronously starting permanent magnet synchronous motor. Background technique [0002] With the progress and development of society, human beings' requirements for low-carbon environmental protection are increasing with time. Rare earth permanent magnet motors are more and more widely used in various machinery manufacturing industries because of their high-efficiency performance. Their applications are mainly divided into two categories. , two types of frequency conversion control drive and asynchronous start synchronous operation, the latter is also called self-starting permanent magnet motor. For self-starting permanent magnet motors, that is, permanent magnet motors with asynchronous start and synchronous operation, the star-delta step-down starting method cannot be used, because the working mode of permanent magnet synchronous motors is designed to work in star connection. ,...

AI Technical Summary

Problems solved by technology

For self-starting permanent magnet motors, that is, permanent magnet motors with asynchronous start and synchronous operation, the star-delta step-down starting method cannot be used, because the working mode of permanent magnet synchronous motors is designed to work in star connection. , the third harmonic is high, and at the same time, the harmonic voltage and harmonic current generated by the third harmonic directly affect the efficiency and working performance of the motor, which directly leads to the characteristics of low efficiency and poor working performance of the permanent magnet motor, because the winding Permanent magnet motors that work in star connection cannot use the star-delta step-down starting method when starting. Therefore, there is a problem of large current impact at the moment of starting for high-power motors. This impact current directly impacts the permanent magnet in reverse. Magnetic field, which leads to the phenomenon of loss of magnetism of the permanent magnet, causing the motor to fail to work normally. At present, there are five methods for the step-down start of the induction motor: 1. The star-delta step-down start method. This method can only be applied to the delta connection method. The operation mode of the windings, and at the same time it cannot meet the long-term starting working time, and cannot be applied to the asynchronous starting permanent magnet synchronous motor; the 2 series reactor method, this method is large in size and high in cost, and it is difficult to obtain in the industry that uses it in batches Application and promotion; 3. The method of connecting resistors in series, which is inconvenient to apply, and the resistance is prone to heat, which has potential safety hazards, which limits the application and promotion; 4. The triangle method of extending the edge, which can only be applied to motors running in delta connection. It cannot be applied to the start of self-starting permanent magnet synchronization; 5. Thyristor soft start method, this method takes up a lot of space and costs high

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