An Inductor Identification Method Based on Current Ripple

Abstract

The invention discloses an inductance identification method based on current ripple, which belongs to the field of online parameter identification of permanent magnet synchronous motors. The identification technology proposed by the present invention completes the sampling of the current ripple of the permanent magnet synchronous motor control system, the processing of the sampling results of the current ripple, and the use of the current ripple to detect the inductance through the cooperation of three continuous control cycles in the digital controller. Perform online identification. The identification technology proposed in the present invention utilizes multiple consecutive sampling and least square fitting to improve the accuracy of current ripple sampling, and utilizes current ripple information through a simplified identification model. Compared with the prior art, the technology proposed by the present invention does not need to inject high-frequency voltage or current signals into the motor, thereby reducing the current distortion and torque fluctuation of the permanent magnet synchronous motor control system, and reducing the motor loss and rotor vibration. .

Description

technical field [0001] The invention relates to the field of online parameter identification of permanent magnet synchronous motors, in particular to an inductance identification method based on current ripple. Background technique [0002] Among the many control algorithms of permanent magnet synchronous motors, such as various current control algorithms, maximum torque to current ratio control algorithms, field weakening control algorithms, position sensorless control algorithms, etc., the inductance value of the dq synchronous coordinate system (L d , L q ) play an important role. To ensure the performance of these control algorithms, online parameter identification techniques are used to obtain accurate L d , L q becomes particularly critical. [0003] The existing on-line identification technology of permanent magnet synchronous motor parameters all use "dq-axis discrete electromagnetic equation with control period as discrete period" as identification model. Using...

AI Technical Summary

Problems solved by technology

Using this identification model causes the existing identification technology to have the following problems: since there are four unknown parameters in the two equations of the d-axis and the q-axis (d-axis inductance L d , q-axis inductance L q , resistance R, permanent magnet flux linkage ψ f ), so when performing parameter identification, you will encounter the problem that the identification model is not rank-satisfactory

In severe cases, it may even destabilize the permanent magnet synchronous motor

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