DC power supply loop, voltage fluctuation processing method and device thereof, and controller

Abstract

The embodiment of the invention provides a DC power supply loop, a voltage fluctuation processing method and device thereof and a controller, which relate to the technical field of electric power. Theinput voltage of the electric load in the DC power supply loop is monitored, the power supply in the DC power supply loop is controlled to be turned off according to the drop speed of the input voltage, the impact current possibly generated due to the fact that the input voltage of the electric load rises again after being sharply reduced is avoided, and the probability of various potential safety hazards caused by the impact current is reduced.

Description

technical field [0001] The application belongs to the field of electric power technology, and in particular relates to a DC power supply circuit, a voltage fluctuation processing method, device and controller thereof. Background technique [0002] At present, in a high-voltage DC circuit system, such as a high-voltage DC power supply system used in a vehicle air conditioner, there will be a large number of capacitive loads. The moment the high-voltage circuit is closed, because the voltage across the capacitor is zero, a huge surge current will be generated at the moment the circuit is closed, especially when the car air conditioner contains a large-capacity filter capacitor, the surge current can even reach more than 100A-1000A. In severe cases, it may cause high-voltage circuit fuses to blow or DC contactor contacts to stick. Therefore, the usual practice is to design a pre-charging circuit to prevent instantaneous inrush current, that is, connect a pre-charging contactor...

AI Technical Summary

Problems solved by technology

[0003] However, during the operation of the system, due to the different control logics of the battery management systems (BMS) of different manufacturers, the high-voltage contactor powering the air conditioner may disconnect and then quickly engage, or some The abnormal phenomenon causes the high-voltage contactor to be disconnected and then quickly closed

At this time, due to the slow discharge of the large-capacity capacitor inside the air conditioner, when the original power supply voltage V1 drops to a certain voltage V2, the main circuit cannot be disconnected in time. When the power supply output high-voltage contactor pulls in again, A V1-V2 pressure difference will be generated in the loop system. When the pressure difference reaches a certain level, an inrush current will be generated due to a sudden change in voltage, which will burn the fuse or cause the DC contactor to stick, leaving a potential safety hazard.

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