Constant current resonant DC conversion circuit and method adapting to high parasitic parameters of transformer

Abstract

The invention discloses a constant current resonance type DC (Direct Current) conversion circuit and a method thereof capable of adapting to transformer high parasitic parameters. The circuit comprises an inverter circuit, a resonance circuit, a compensation circuit and a rectifier circuit. The inverter circuit enables an original power input current signal connected with the inverter circuit to be inverted to an AC (Alternating Current) signal; the resonance circuit receives the AC signal provided by the inverter circuit; the compensation circuit is provided with a transformer model circuit,a first inductive and reactive compensation capacitor and a second compensation capacitor, wherein the first inductive and reactive compensation capacitor is used for compensating circuit consumptionof a transformer model, and the second compensation capacitor of current precision is used for compensating current accuracy of the transformer model circuit; the rectifier circuit converts the AC signal output by the compensation circuit to the DC signal which does not vary with load resistance. Current output by the circuit of the invention does not vary with load, and an inductive component ofthe transformer is compensated under the action of the compensation capacitors. Consequently, reactive power of the system is reduced, running efficiency of the circuit is increased, and the problem that accuracy of output current is poor is improved.

Description

technical field [0001] The invention relates to the design field of a constant-current resonance type DC conversion system, in particular to a constant-current resonance type DC conversion circuit and method adaptable to high parasitic parameters of a transformer. Background technique [0002] With the application of battery packs in various high-power transportation systems, including automobiles, ships, aerospace and other fields, and with the continuous improvement of power and voltage levels, the charging voltage of battery packs is getting higher and higher. The traditional voltage source topology When it is applied to the charging of high-voltage battery packs, it often encounters the following difficulties: [0003] (1) The charging voltage of the high-voltage battery pack is very high, and the application of the voltage source topology requires a large gain. The single-stage conversion is very difficult, and the efficiency of the two-stage conversion is low. [0004...

AI Technical Summary

Problems solved by technology

[0003] (1) The charging voltage of the high-voltage battery pack is very high, and the application of the voltage source topology requires a large gain, and the single-stage conversion is very difficult, and the efficiency of the two-stage conversion is low

[0004] (2) Most of the time when the battery is charged, it is in the constant current charging state. Applying the voltage source topology to the constant current working state makes it difficult to work at the optimal operating point and the work efficiency is low.

In the actual circuit, the transformer has parasitic parameters dominated by leakage inductance and excitation inductance, which affects the accuracy of the circuit output current, and due to the inductive component brought by the transformer leakage inductance, the circuit reactive power is large, which affects the circuit efficiency

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