Battery charging circuit which outputs step current

Abstract

The invention discloses a battery charging circuit which outputs step current. The circuit comprises an input voltage source, a capacitor, n inductors L1 to Ln, n switch tubes S1 to Sn and n diodes D1 to Dn. A three-phase Boost circuit is employed, through changing the frequency, duty cycle and phase of a control signal, the step charging current with adjustable output amplitude and frequency can be obtained. Compared with the existing charging mode, the step current charging mode is employed, the charging performance such as charging efficiency and battery temperature rise is improved with different degrees, the battery charging circuit can be applied to occasions of high frequency, high current and high power, the battery charging circuit can be used in a small-power charger and a large-power electric car and has a significant improvement effect in a fast charging occasion, and the application range of the battery charging circuit is more extensive.

Description

technical field [0001] The invention belongs to the technical field of power electronics, and in particular relates to a battery charging circuit for outputting ladder current. Background technique [0002] In recent years, due to the rapid development of portable electronic devices, electric vehicles and renewable energy, batteries used for energy storage units and corresponding charging technologies have been more and more extensively researched; at present, various battery charging methods have appeared, such as trickle Current charging, constant current charging, constant voltage charging, etc. Constant current-constant voltage (CC-CV) charging is the most commonly used charging method. This method is a constant current stage in the early stage of charging, and keeps the charging current at a fixed value, which can ensure the charging rate without causing The charging current is too large, and the later stage is a constant voltage stage. The charging current decreases d...

AI Technical Summary

Problems solved by technology

image 3 It is a sinusoidal current charging technology applied to lithium batteries. It uses different frequencies of sinusoidal current charging, pulse charging and constant current-constant voltage charging to charge the same lithium battery, and you can see the best frequency of sinusoidal current charging. The charging characteristics such as charging efficiency, temperature rise and battery life have been improved to varying degrees under this method; however, this method can only be used for low-power chargers, and the current and power levels cannot be further improved, thus limiting its further development. application

[0006] In addition, there are more efficient charging methods such as artificial neural network, genetic algorithm, ant colony algorithm, gray prediction, etc., but the circuits of these charging methods are more complicated, so the cost is correspondingly increased

The above-mentioned existing charging technologies may have problems such as low charging efficiency, narrow frequency range, low current and power levels, complex circuits and control methods, and high cost.

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