Electronic temperature controller of transformer

Abstract

The invention relates to an electronic temperature controller of a transformer, comprising a man-machine interactive board and a measurement and control circuit board, wherein the man-machine interactive board is provided with an operation keyboard and a display, the measurement and control circuit board comprises a cooling fan control circuit, a temperature control man-machine interface circuit, a microprocessor system, a temperature controller power circuit, a transformer temperature acquisition circuit, a serial communication interface circuit, a cooling fan overload / phase failure detection circuit and a cooling fan phase failure protection circuit; the input end of the cooling fan phase failure protection circuit is connected with the microprocessor system, and the output end is connected with a three-phase cooling fan; the cooling fan overload / phase failure detection circuit is connected with the microprocessor system; and the input end of the cooling fan overload / phase failure detection circuit is connected with the three-phase cooling fan, and the output end thereof is connected with a cooling fan overload / phase failure alarming circuit and equipment. The electronic temperature controller has the beneficial effects of integrating temperature acquisition and measurement of the temperature controller, fan control, fan overload / phase failure detection, phase failure protection, power failure alarm and other functions, and having low cost and high reliability.

Description

technical field [0001] The invention belongs to the field of general power transformer temperature control and relates to a transformer electronic temperature controller. Background technique [0002] The electronic thermostat used for transformer temperature detection and refrigeration fan control is one of the important devices to ensure the safe operation of transformers. At present, the temperature control of transformers generally uses PT 100 platinum resistance as the temperature detection sensor of the transformer, and single-phase or three-phase fans are used as the actuator for temperature control. The microprocessor is used to calculate and process the temperature of the transformer collected by the temperature sensor, and according to the collected The temperature of the transformer is used to control the switching of the cooling fan, and output alarm information such as transformer over-temperature alarm, temperature sensor failure, etc., and control signals such...

AI Technical Summary

Problems solved by technology

[0013] Ordinary power transformer electronic temperature controller (system structure see figure 1 ) Most of them have the above functions, but they do not have the functions of fan failure detection and phase failure protection, that is, ordinary thermostats cannot detect when the cooling fan is overloaded or phase failure, and the overload or phase failure of the cooling fan is easy to cause damage to the fan, and the fan is damaged. Finally, if it is not found in time, the transformer will run without cooling measures, which will easily cause the transformer to stop running or be damaged after the temperature rises.

In order to detect the failure of the cooling fan and realize the phase failure protection function of the three-phase fan, at present, the electronic temperature controller of the ordinary power transformer, an AC contactor (or AC relay) and a thermal relay (or other phase failure detection device) are generally used to form a temperature controller. Control box way to achieve, see figure 2 , its structure is complicated, it is inconvenient to use, and it cannot perform power failure alarm, and its function has limitations

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