Method for automatically identifying and judging reasons causing circuit overcurrent protection

Abstract

The invention discloses a method for automatically identifying and judging reasons causing circuit overcurrent protection. The method comprises the following steps: S1, switching on a circuit; S2, opening a field effect transistor in the circuit loop; S3, current is generated in the loop, and the current value is sampled; S4, if the sampled current value is too large and overcurrent protection isneeded, closing the field effect transistor of the loop; S5, repeatedly executing the steps S2-S4 for a plurality of times; recording the time when the current reaches the overcurrent point from 0 asT1, T2... Tn each time; S6, judging the time duration characteristics of T1, T2... Tn, and judging the cause of overcurrent protection. The reasons of overcurrent protection can be intelligently and effectively analyzed and judged, overcurrent protection caused by different conditions is treated differently, overcurrent protection of the circuit is more accurate and effective, the stability and fault tolerance of the system are improved, and finally better satisfaction is provided for users.

Description

technical field [0001] The invention relates to the technical field of circuit overcurrent protection, in particular to a method for automatically identifying and judging the cause of circuit overcurrent protection. Background technique [0002] The existence of capacitive load is inevitable in the application of any circuit. When the voltage source starts with a large capacitor, it needs to charge the capacitor quickly to maintain the output voltage stability. A large current will be generated at the moment of startup. In this moment It is equivalent to a short circuit of the power supply. This huge current may even exceed the overcurrent detection point of the circuit. If the high current lasts long enough, the overcurrent protection circuit of the power supply will activate and shut down the output. If preventive measures are not taken to intervene in such a situation, the application circuit where the capacitive load exists will affect the output circuit of the power su...

AI Technical Summary

Problems solved by technology

[0005] Therefore, it is necessary to find a method that can correctly judge the capacitive load and output short circuit, avoid circuit misjudgment, and protect the capacitive load circuit as an output short circuit to prevent the power supply from starting normally; or treat the output short circuit as a capacitive load. Judgment, the circuit is damaged after repeated startup and shutdown

Images