Engine exhaust temperature thermocouple detection circuit

Abstract

The invention provides an engine exhaust temperature thermocouple detection circuit, and relates to an engine exhaust temperature detection circuit which is high in test reliability and small in feed circuit ripple. The engine exhaust temperature thermocouple detection circuit is implemented through the following technical scheme, a thermocouple differential input instrument amplification unit and a thermocouple loop detection unit are electrically connected with an AD conversion unit through the positive end and the negative end of a thermocouple sensor to form a thermocouple loop detection circuit, and the output voltage of a thermocouple cold-end collection unit is fed into the AD conversion unit through a cold-end temperature processing unit and calculated through a CPU so that the cold-end temperature can be obtained. A thermocouple feed unit divides the reference voltage into two paths through an external T45 temperature sensor, and the thermocouple sensor negative-end voltage is fed to the AD conversion unit by one path of the reference voltage through the thermocouple loop detection unit; the other path of the reference voltage is input into the thermocouple differential input instrument amplification unit through feeding of the thermocouple sensor, and after a voltage difference signal is differentially amplified, the differentially amplified voltage difference signal is collected by an AD converter, and is fed into the CPU so that a thermocouple fault can be judged.

Description

technical field [0001] The invention relates to collecting engine exhaust temperature through thermocouples, and a temperature acquisition circuit for detecting the engine exhaust temperature, especially a detection circuit for thermocouples at the exhaust port of aeroengines. Background technique [0002] Aeroengine exhaust temperature is an important parameter to determine the characteristics of the turbine and engine performance, and the detection of gas temperature after the turbine is an important part of engine performance detection, which directly affects the safety and life of the engine. When the jet temperature of the aircraft engine exceeds the limit temperature, the engine must be controlled by limiting fuel or stopping the engine so that the exhaust temperature of the engine does not exceed the specified value to ensure flight safety. This requires that the jet temperature of the aircraft engine can be measured timely and accurately during the flight process of ...

AI Technical Summary

Problems solved by technology

However, the commonly used thermocouple detection technology cannot reasonably solve the individual differences of thermocouples, resulting in poor versatility of engine electronic controllers

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