Parallel current sharing circuit of charging module of electric automobile charger

Abstract

The invention provides a parallel current sharing circuit of a charging module of an electric automobile charger, comprising a charger monitoring unit and at least one charging module which are connected in parallel, wherein the charging modules are linked in parallel; the charger monitoring unit is connected with the charging modules through communication signal lines; and the charging modules are connected through average current signal lines, and connected with a grid alternating current end and a power battery direct current end of the electric automobile respectively. By using the current sharing circuit disclosed by the invention, the sampling feedback coefficient of the output voltage of the module is adjusted according to the differential value between a module charging current sampling signal and average current signals of all the parallel modules, thus the charging voltage and the charging current of the module are further adjusted to reach the purpose of load-sharing current in parallel of every charging module. The parallel current sharing circuit has relatively high current sharing precision and current sharing dynamic responding speed, is beneficial to improving the reliability and the maintainable performance of the charger and better satisfies the charging requirement of the power battery of the electric automobile.

Description

technical field [0001] The invention relates to the field of electric vehicles, in particular to a parallel current sharing circuit of a charging module of an electric vehicle charger. Background technique [0002] As a new type of transportation, electric vehicles have incomparable advantages in alleviating the energy crisis and promoting the harmonious development of the environment and human beings. The construction of charging facilities such as charging stations is the premise and foundation for the healthy development of the electric vehicle industry. A typical electric vehicle charging station mainly includes power supply system, charging system, monitoring system and civil engineering and other auxiliary facilities. Among them, the charging system of the charging station mainly includes AC charging piles and off-board chargers, which are the core equipment of the charging station. [0003] Electric vehicle charger (i.e. non-vehicle charger) refers to a special devi...

AI Technical Summary

Problems solved by technology

This current sharing control method works well, but the disadvantage is that the master and slave modules are always in constant switching, which will cause low-frequency oscillation of the output current of each module; and because each slave module uses the maximum current as the adjustment purpose, it will inevitably make the The output voltage of the parallel system is higher than the rated voltage, resulting in overvoltage, and the larger the output impedance of the power supply, the more obvious the overvoltage phenomenon

[0008] The shortcomings and deficiencies of the existing parallel current sharing control method limit the overall performance of the parallel operation of the charging module of the electric vehicle charger, and affect the industrialization and application of the electric vehicle charger.

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