BAR TEMPERATURE MEASUREMENT SYSTEM FOR ELECTRICAL BOARDS Russian patent published in 2021 - IPC G01K11/26 

FIELD: radio engineering; measuring equipment.

SUBSTANCE: invention relates to the field of radio engineering and measuring equipment, can be used for remote measurement of temperature by radio in multi-sensor monitoring systems for the prevention of emergency situations when monitoring the temperature of the connection points of the bars of electrical boards. Passive radio frequency measuring elements based on surface acoustic waves (hereinafter – SAW) are used as temperature sensing elements. The system contains N sensors mounted on buses, each of which contains a sensing element (hereinafter – SE) made on a delay line on surface acoustic waves (SAW) containing a piezoelectric substrate, on the surface of which a counter-pin converter (hereinafter – CPC) and at least three reflectors are applied, offset by a different distance relatively to the CPC. The first reflector has the shortest delay time; the second reflector is located in the middle part of the surface of the piezoelectric substrate; the third reflector is located at the end of the piezoelectric substrate, thus, that their relative position determines the reference (calibration) delay time of the SAW (over the entire range of changes in the controlled physical value). Each SE of N sensors with anti-collision characteristics within one set (system), by shifting groups of reflectors (1, 2 and 3) on each SE substrate, providing different delay times for SAW responses, is installed in a sealed case. The CPC of the SE is connected by pins to a directional antenna fixed through a dielectric gasket on the base of the sensor made of a heat-conducting material, and the sealed case of the SE (the side opposite to the pins) is connected to the base of the sensor by a thermal bridge through a heat-conducting paste. In front of each of the N sensors, M directional reader antennas are installed to poll the sensors and receive response signals from the sensors. Each of the M directional antennas is connected to the reader by its own cable, and the reader itself is connected to the power source and to the computer via one of the standard interfaces (for example, via the RS-485 interface). When the number of sensors N is equal to the number of directional antennas M, the corresponding antennas N and M are located opposite each other, while providing a “point-to-point” reception/transmission mode for maximum noise immunity. If the number of sensors N is greater than the number of directional antennas M, each of the directional antennas M is located opposite several sensors N, which it polls and receives response signals from them, while it remains possible for any of the directional antennas M to obtain the temperature value of its own, as well as adjacent sensors N, falling within the scope of the directional antenna M due to the property of anti-collision within one set of sensors.

EFFECT: creation of a system for monitoring the temperature of the connection points of the bars of electric boards with sensors of increased service life at operating voltages of the bars of electric boards from 0.4 to 110 kV.

3 cl, 8 dwg