A method for phase shift control of a charging circuit

Abstract

The invention discloses a phase shift control method of a charging circuit, which comprises a primary side conversion circuit, a secondary side first conversion circuit and a secondary side second conversion circuit. The controller has a phase angle difference phi between the on-off waveform of the power switch in the primary side conversion circuit and the on-off waveform of the power switch in the secondary side first conversion circuit; The controller collects the output current (Io1) and the output voltage (Vo1) of the secondary side first conversion circuit through the secondary side first current collector and the secondary side first voltage collector, comparing and calculating the collected output current and output voltage with the preset output current and output voltage, and adjusting the magnitude and positive and negative of the phase angle difference phi according to the comparison result; The magnetic flux in the transformer can be stabilized when the main circuit outputs light load and no load, and the auxiliary circuit can normally absorb electric energy from the transformer and normally supply power to the outside. At the same time, it can conveniently control theconversion direction and the conversion quantity of the electric quantity in each port.

Description

technical field [0001] The invention relates to the technical field of electric vehicle charging, in particular to a phase-shift control method for a charging circuit with three ports. Background technique [0002] With the demand for energy saving and emission reduction, as well as the control of air pollution, new energy vehicles are gradually being promoted and used in the market, among which electric vehicles are the main force of new energy vehicles. The on-board charger of an electric vehicle is an important part of an electric vehicle. The on-board charger generally has an AC input terminal and two DC output terminals. The AC input terminal is connected to the mains network, and the first DC output terminal charges the high-voltage battery. It is equivalent to the output of the main circuit; the second DC output terminal supplies power to the electrical equipment in the car and a small low-voltage battery, which is equivalent to the output of the auxiliary circuit. I...

AI Technical Summary

Problems solved by technology

The impact of this problem is that the output power of the main road will also affect the output power of the auxiliary road

For example, when the output power of the main circuit is small or no-load (equivalent to that the high-voltage battery at the first DC output terminal is about to be fully charged or has already been fully charged), the main control will issue a small duty cycle, and even enter the intermittent working mode. When the magnetic flux in the transformer is very small, or almost zero, the induced voltage on the winding of the auxiliary circuit may also be zero. will not be able to meet the needs of use

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