Method for achieving overcurrent protection by detecting temperature change rate of carrier wire

Abstract

A method for achieving overcurrent protection by detecting temperature change rate of a carrier wire is characterized in that the temperature change of the carrier wire is sampled by additionally arranging a temperature sampling resistor aside the carrier wire, the sampling is analyzed to obtain a change trend of a temperature and a curve drawn by temperature change according to fixed sampling time intervals, the change rate data of the curve is analyzed, the temperature is normal if the curve is within a certain temperature range and belongs to an overcurrent protection region if the curve exceeds, the temperature rising amplitude is needed to be judged, the temperature rising change is calculated by an algorithm during the whole process to obtain overcurrent judgment, and overcurrent protection of the carrier wire is achieved. Under the condition of carrier, the temperature change rate of the carrier wire is detected to judge abnormal overcurrent of the wire by additionally arranginga thermistor aside the carrier wire; since a temperature change relative value is taken, the acquired data is not needed to be processed, so that a peripheral circuit reaches the simplest scheme; andby combining the simplest temperature detection and singlechip microcomputer software, the required circuit cost is greatly reduced, and the economic benefit is obvious.

Description

technical field [0001] The invention relates to a method, in particular to a method for detecting the temperature change rate of a small current-carrying wire to realize overcurrent protection. Background technique [0002] At present, the current detection of household and similar electrical appliances (electric appliances) mainly detects the current through the voltage division on the current transformer or the sampling resistor (constantan wire). [0003] The current transformer solution has a complex structure and a large volume, and there are many sampling line components, which is difficult to process and high in cost. [0004] However, the constantan wire resistance divider sampling requires precision amplification and filtering processing for the collected signal, which is expensive, and requires zero calibration of the line, making production difficult, inefficient and complicated. [0005] At present, there is also a solution to obtain the current value through te...

AI Technical Summary

Problems solved by technology

[0003] The current transformer scheme has a complex structure and a large volume, and there are many components in the sampling line, which is difficult to process and high in cost

[0004] However, constantan wire resistance divider sampling requires precision amplification and filtering processing for the acquisition signal, which is expensive and requires zero calibration of the line, making production difficult, inefficient and complicated.

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