A positioning current control method of variable frequency motor

Abstract

The invention relates to an air conditioner control technology, which discloses a positioning current control method of a variable frequency motor, which solves the problem that in the traditional permanent magnet synchronous DC brushless motor positioning technology, the power-on sequence of the upper and lower six IGBTs will not change, resulting in different service life of the IGBTs. . The positioning current control method of the variable frequency motor in the present invention includes: controlling the change of the d-axis current from 0 to the positioning target current Id0, controlling the q-axis current to be 0, and controlling the positioning angle θ to be 0 degrees when the positioning is started for the first time; When the positioning is started, the control positioning angle θ is changed by a fixed angle n relative to the previous positioning. The invention can make the average time of each IGBT conduction equal during positioning, and the service life of the IGBT is not affected by the positioning, prolongs the service life of the IGBT, solves the problem of inconsistency of the life of the IGBT in the traditional positioning method, and improves the service life of the product. It is used for positioning current control of frequency conversion motor of air conditioner.

Description

technical field [0001] The invention relates to an air conditioner control technology, in particular to a positioning current control method of a variable frequency motor. Background technique [0002] The traditional permanent magnet synchronous DC brushless motor positioning method adopts positioning current control, and the positioning current is generally controlled by d-axis current not equal to 0, and q-axis current is 0, but the direction of the space vector formed by the positioning current is fixed, only changing The magnitude of the positioning current, the angle θ between the space vector and the fixed coordinate axis α remains unchanged, forcing the rotor to rotate to the direction of the current vector. Using this method for positioning will cause the power-on sequence of the upper and lower six IGBTs to be different each time it is started. It will change. Some IGBTs (insulated gate bipolar transistors) have a long power-on time, some have a short power-on time...

AI Technical Summary

Problems solved by technology

[0004] The technical problem to be solved by the present invention is: to propose a variable frequency motor positioning current control method to solve the problem that in the traditional permanent magnet synchronous DC brushless motor positioning technology, the power-on sequence of the upper and lower six IGBTs will not change, resulting in different service life of the IGBTs.

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