Vehicle-mounted charging device for electric vehicles

Abstract

The invention discloses a vehicle-mounted charging device for electric vehicles, which comprises a voltage detection unit, a power supply management unit and a switching power supply which are interconnected in sequence, a microcontroller which is respectively connected with the voltage detection unit, the power supply management unit and the switching power supply, and a CAN bus system connected with the microcontroller; the power supply management unit is connected with the CAN bus system, the switching power supply and the CAN bus system are respectively connected with batteries, to be charged, of the electric vehicle, wherein the voltage detection unit comprises a digital converter, a voltage comparator and a sampling circuit; the power supply management unit comprises a power supply converter; the switching power supply comprises a numerical control-regulated drive circuit; and the CAN bus system comprises a CAN bus transceiver circuit and an analog-digital conversion chip with a CAN interface. Being capable of replacing fixed charging stations, the device according to the invention can realize site charging according to the voltage situation at vehicle locations, representing the convenience; and the variable power charging technique adopted can achieve the charging with different powers for the battery of vehicle.

Description

technical field [0001] The invention relates to a vehicle-mounted charging device for an electric vehicle, in particular to a vehicle-mounted portable charging device which can self-adaptively charge the electric vehicle under certain circumstances. Background technique [0002] With the rise of electric vehicles at home and abroad, the charging technology of electric vehicles has attracted much attention. Due to the large capacity and output power of electric vehicle batteries, electric vehicle batteries are generally charged quickly through special devices such as high-power charging stations at locations designated by automobile manufacturers. At present, charging stations are limited by the promotion of electric vehicle technology, and have not yet been fully popularized. The distribution of charging stations is limited, and there are almost no dedicated charging stations in rural areas. In addition, these charging stations are generally fixed and do not have the charac...

AI Technical Summary

Problems solved by technology

At present, charging stations are limited by the promotion of electric vehicle technology, and have not yet been fully popularized. The distribution of charging stations is limited, and there are almost no dedicated charging stations in rural areas.

In addition, these charging stations are generally fixed and do not have the characteristics of vehicle movement

Moreover, compared with internal combustion engine-driven vehicles, current electric vehicles can only run a very limited distance on a single charge due to the limitation of battery technology. These conditions have exacerbated the difficulty of charging electric vehicles and affected their popularization, especially in rural areas. area

[0003] When an electric vehicle travels to an area without a dedicated charging station, it usually uses the charging equipment carried on the vehicle to complete the charging. In some rural areas, the output power of the power supply transformer is very limited. If the electric vehicle is charged with a fixed output high power, it may cause damage to the circuit in the power grid due to too much power, which will seriously affect the rural electricity consumption.

Another situation is that sometimes the location (rural or urban) where electric vehicles need to be charged has been tested, and the grid voltage is overloaded due to many users or other high-power electrical equipment is already in use, and the voltage is low. Forcibly carrying out high-power charging may cause the voltage of the grid to be lower due to the increased load, which will cause certain damage to the grid and affect the power consumption of other users.

However, if we take the method of waiting for the grid voltage to recover, it will waste a lot of time, and even the voltage cannot be recovered at all, so it cannot be charged.

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