Self-heating differential thermoresistor liquid level sensor and liquid level measurement method thereof

The invention belongs to the field of the sensor technology thermal parameter measurement, and particularly relates to a self-heating differential thermoresistor liquid level sensor and a liquid level measurement method thereof. According to the method, identical parts of two sheathed thermoresistors which are same in structure and equal in mass and serve as sensitive elements are put at the position of a measured liquid level; the thermal resistance wire of one of the sensitive elements is electrified to be heated and serves as a measurement element; the thermal resistance wire of the other sensitive elements is not electrified and serves as a compensating element; with the change of the liquid level, the resistance difference value of the thermal resistance wires of the two sensitive elements is measured through a resistance value measurement circuit, and liquid level height is worked out according to a relation between liquid level height obtained from experiments and the resistance difference value. The liquid level sensor provided by the invention is simple in structure, reliable in performance, high in sensitivity and high in anti-jamming capability.