Protection method for charging in starting vehicle low voltage DCDC (direct current/direct current) transducer

Abstract

The invention belongs to the technical field of vehicle electron, and relates to a protection method for charging in starting a vehicle low voltage DCDC (direct current/direct current) transducer. The protection method comprises the following step that after a low voltage DCDC transducer is started, the output voltage of the low voltage DCDC is controlled to take an initiate voltage as a start point, and loading is carried out in every certain time according to a certain step length. Meanwhile during the process of voltage loading, the output current of the DCDC transducer is subjected to real-time monitoring, and when the output current of the DCDC transducer reaches a current protective value, limitation is carried out on a voltage. According to the method, stable rise of the output voltage of the DCDC transducer is realized, and stability in starting is guaranteed; and meanwhile maximum linear promotion of the output voltage of the DCDC transducer is realized in a current allowance range, and the speed and the safety are guaranteed. By the adoption of the method, current is limited by limiting the voltage, and the low voltage DCDC transducer and a low voltage storage battery are protected from being impacted.

Description

technical field [0001] The invention belongs to the field of automotive electronics, and relates to a charging method for a vehicle charging device, in particular to a charging protection method suitable for starting a vehicle-mounted low-voltage DC-DC converter of a fuel cell vehicle, a pure electric vehicle and a hybrid vehicle. Background technique [0002] Vehicle-mounted low-voltage DCDC converter is one of the key equipment for fuel cell vehicles, pure electric vehicles and hybrid vehicles. It mainly provides stable low-voltage power supply for various controllers and low-voltage equipment, including ECU, power steering, brake control, low-voltage cooling fan, and low-voltage water pump. Wait, it plays a vital role in the stability of the entire vehicle system. The input end of the vehicle-mounted low-voltage DCDC converter is a power battery, and the output end is connected to a low-voltage battery. The low-voltage battery is generally a lead-acid battery. After the ...

AI Technical Summary

Problems solved by technology

The low-voltage battery is generally a lead-acid battery. After the vehicle is started at high voltage, the on-board low-voltage DCDC converter starts. Due to the characteristics of the low-voltage battery itself, when there is no protection, the output current is relatively large, which has a relatively large negative impact on the DCDC converter itself and the battery.

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