Mutual inductance identification method for wireless charging system based on orthogonal dual-channel algorithm

Abstract

The invention provides a mutual inductance identification method for a wireless charging system based on an orthogonal dual-channel algorithm. The method analyzes a relationship between mutual inductance values and system circuit parameters by using a mutual inductance model, thereby deducing a functional relation expression for achieving an online / offline mutual inductance identification algorithm. The method of the invention is applicable to different compensation topologies and magnetic coupling mechanisms, and has low algorithm complexity, short calculation time and high mutual inductanceidentification accuracy. In addition, the method can not only realize the mutual inductance identification under an offline state, but also can realize the mutual inductance identification of a dynamic wireless charging system, thereby being greatly improved in engineering practicability.

Description

technical field [0001] The invention belongs to the technical field of wireless charging, and in particular relates to a mutual inductance identification method for a wireless charging system based on an orthogonal dual-channel algorithm. Background technique [0002] As a new type of power transmission technology, wireless charging technology has completely got rid of the problems of interface inconsistency, mechanical wear and environmental influence in conductive charging, and has attracted close attention from domestic and foreign scientific research institutions and companies. Generally speaking, according to whether the position of the receiving end changes dynamically during the charging process, wireless charging technology can be divided into static and dynamic forms. Among them, the static wireless charging technology is applied to the equipment charging where the energy receiving end (secondary side part) is fixed relative to the energy transmitting end (primary s...

AI Technical Summary

Problems solved by technology

Aiming at the series-series (SS) compensated magnetically coupled wireless power transmission system, some literature proposes a mutual inductance estimation method based on frequency adjustment under the premise that the system operating frequency is offset from the natural frequency of the system; the defect of the method is that the system works When the frequency deviates from the natural frequency, it often leads to a reduction in system power and efficiency

There are also literatures that measure the two instantaneous values ​​of the output voltage of the magnetically coupled wireless power transfer system, and calculate the dynamically changing mutual inductance value through mathematical formulas. The problem is that this method needs to use a dc-dc converter on the secondary side, which will lead to system costs and Increased volume and affects system efficiency

There are also literatures that propose a global search algorithm for the optimal value of mutual inductance by establishing a time-domain model of the system. The problem is that the calculation amount of the algorithm is huge and the time-consuming increase

Another literature estimates the mutual inductance value by measuring the voltage and current of the secondary resonant circuit. The problem is that when there are large harmonics in the voltage and current, it will lead to a large error in the estimated mutual inductance value.

[0005] To sum up, in the prior art, when performing mutual inductance identification on a magnetically coupled wireless power transfer system, either additional hardware circuit topology is required, or the algorithm is complex and time-consuming, or the system parameters are demanding and the error is large. Big

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