| CPC G05D 23/2401 (2013.01) [H05B 3/18 (2013.01); H05B 2203/007 (2013.01); H05B 2203/02 (2013.01)] | 8 Claims |
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1. A temperature-sensitive PTC heating wire, comprising a first metal wire (1), a temperature detection module (2), and a temperature regulation module (3);
the first metal wire (1) is configured to generate heat when a heating current flows therethrough;
the first metal wire (1) has a known temperature-resistance relationship and a positive temperature coefficient (PTC) characteristic;
the temperature detection module (2) is configured to acquire a real-time resistance of the first metal wire (1), and calculate a real-time temperature of the first metal wire (1) on the basis of the temperature-resistance relationship;
the temperature regulation module (3) is configured to compare the real-time temperature with a preset target temperature, and regulate the real-time temperature to the preset target temperature by means of closed-loop control; and
wherein the temperature detection module (2) comprises a constant current source module (2-1), configured to provide a constant current to the first metal wire (1) during a sampling time slot; the sampling time slot being a time period, during which no heating current flows through the first metal wire (1), in a heating process of the first metal wire (1);
a voltage acquisition unit (2-2), configured to acquire a real-time voltage across both ends the first metal wire in real time;
an analog-to-digital conversion module (2-3), configured to calculate a real-time resistance value of the first metal wire (1) on the basis of the real-time voltage and the constant current; and
a temperature calculation unit (2-4), configured to convert the real-time resistance value into a real-time temperature value.
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