Passive temperature measuring sensor of substation primary equipment

Abstract

The invention provides a passive temperature measuring sensor of substation primary equipment. The passive temperature measuring sensor comprises a radio frequency receiving circuit, a temperature sensing circuit, a digital logic circuit and a storage unit. The radio frequency receiving circuit comprises a coupling element, a rectifying circuit, a voltage stabilizing circuit and a modulation and demodulation circuit. The temperature sensing circuit comprises a capacitance temperature measuring circuit and an analog-digital converter. The digital logic circuit comprises a coder / decoder and a logic controller which is in bidirectional signal electric-connection with the coder / decoder. The radio frequency receiving circuit responds to excitation signals in the frequency same as or approximate to inherent frequency of the coupling element and selectively senses the temperature of detected equipment by means of frequency of surface acoustic wave coupling element. The capacitance temperature measuring circuit measures capacitance-temperature characteristics, maps the relation of capacitance and temperature, and outputs signals corresponding to the temperature according to the capacitance bridge theory. The passive temperature measuring sensor adopting the passive temperature measurement technology is high in interference resistance and applicability, high in integrity, convenient in implement and low in cost.

Description

technical field [0001] The invention relates to the technical field of temperature detection of primary equipment in substations, in particular to a passive temperature measurement sensor suitable for temperature measurement of primary equipment in substations. Background technique [0002] There are more than 500 primary equipment temperature monitoring points in each substation. If manual inspection is performed according to the specified inspection cycle, the amount of inspection and recorded data will be huge. The existing temperature measurement technology cannot meet the requirements of daily inspection. At present, the temperature measurement methods of primary equipment in substations mainly include temperature test wax sheet method, temperature display record label method, infrared temperature measurement method or far infrared camera temperature measurement, optical fiber temperature measurement method, etc. In the temperature test wax chip method, when the tempera...

AI Technical Summary

Problems solved by technology

The general design is to install the temperature sensor at the position where the temperature rise of the equipment may occur, and transmit the signal through the connection between the passive sensor and the temperature sensor, which is bulky and inconvenient to use

The ideal solution is to embed the temperature sensor in a passive sensor, because the chip consumes a lot of power and cannot be integrated into a passive chip, or it is greatly affected by the magnetic field, such as a thermistor, which is difficult to adapt to the substation. Working environment with strong magnetic field and strong interference

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