Novel vehicle-mounted electric automobile battery charger and control method thereof

Abstract

The invention discloses a novel electric automobile charging circuit and a control method thereof. The circuit comprises a control unit and a main circuit, wherein the main circuit comprises a high frequency circuit and a power frequency circuit; the power frequency circuit comprises a charging input end, a half-bridge PWM rectifier and an energy storage capacitor which are connected in sequence;the input end of the half-bridge PWM rectifier is connected to a resonance circuit, a high frequency isolation transformer, a high voltage rectifier filter circuit, a low voltage rectifier filter circuit, a low voltage output end and a charging output end to form the high frequency circuit; and the control unit is used for controlling the operation of the half-bridge PWM rectifier and the operation of the rectifier filter circuit according to obtained voltage and current information. Power factor correction and the soft-switching technology of a high voltage rectifier bridge are realized, thequantity of switching devices required for a battery charger can be reduced effectively, the volume of the transformer is reduced, the quantity of transformers can be reduced due to the application ofa three-winding transformer, the efficiency of power transmission is improved, and the volume and cost of the system are reduced.

Description

technical field [0001] The invention belongs to the technical field of electric vehicle charging, and relates to a novel vehicle-mounted two-way electric vehicle charger and a control method thereof. Background technique [0002] With the development of modern high-tech and the increasingly prominent problems of environment and energy in today's world, electric vehicles have become the focus of the automotive industry due to their superior environmental protection characteristics. With the promulgation of a number of national support policies for new energy vehicles, the pace of development of new energy vehicles is accelerating, and the pace of construction of charging infrastructure is also accelerating. At present, some chargers still use a more traditional structure, simply connecting the charging interface, bidirectional AC / DC converter, bidirectional DC / DC converter and power battery in series, which has disadvantages such as low efficiency, insufficient power factor, ...

AI Technical Summary

Problems solved by technology

At present, some chargers still use a more traditional structure, simply connecting the charging interface, bidirectional AC / DC converter, bidirectional DC / DC converter and power battery in series, which has disadvantages such as low efficiency, insufficient power factor, and low energy density.

Patent CN106647332A provides a design method for two-way charging and discharging of automobiles, which can realize two-way power transmission, and can effectively suppress harmonics to ensure power factor, but lacks an electrical isolation module, making it difficult to ensure the safety of users and equipment

Patent CN102222958A provides a vehicle-mounted bidirectional charger for electric vehicles, which uses an isolated dual-active half-bridge bidirectional DC / DC converter to make the conversion performance more efficient and stable, but the charging rate is low and cannot meet the increasing charging speed need

Patent CN102983606A discloses a bidirectional charging system for electric vehicle charging, which is composed of multiple bidirectional AC / DC and DC / DC modules, which improves the adjustable charging and discharging power, and can realize bidirectional transmission of electric energy with high power. However, due to the use of more converter modules, the volume is larger, the power density is lower, and the cost is higher

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