RU2474713C2 - Method of gas turbine engine protection - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: invention may be used in gas turbine engine ACSs. Additionally, "Takeoff Mode Interlocking" signal is generated subject to position of throttle, flaps and aircraft parking brake and engine turbo compressor, to generate turbo compressor minimum tolerable rpm proceeding from throttle position. Minimum tolerable rpm is compared with measured to use obtained mismatch to control fuel consumption in combustion chamber before removing said "Takeoff Mode Interlocking" signal.

EFFECT: higher reliability and safety.

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Description

The invention relates to the field of aircraft engine manufacturing and can be used in electronic hydromechanical systems (ACS) for automatic control of gas turbine engines (GTE).

A known method of protecting a gas turbine engine against overheating of a gas generator, implemented in a hydromechanical self-propelled guns with an electronic gas temperature limiter behind the turbine, consists in measuring the temperature of the gases behind the turbine, comparing its value with the maximum permissible value if the measured gas temperature exceeds the limit value by a predetermined value, turn off the engine, Keba I.V. “Flight operation of helicopter GTE”, Moscow, “Transport”, 1976, p.180-182.

The disadvantage of this method is its low efficiency and the inability to use on single-engine aircraft (LA).

Closest to this invention in technical essence is a method of protecting a gas turbine engine, which consists in measuring the temperature of the gases behind the turbine, comparing its value with the set value, if the measured gas temperature has exceeded the set value, and reducing the fuel consumption in the gas turbine combustion chamber (КС) until then until the measured temperature of the gases becomes less than a predetermined value, in the engine start-up mode at equal time intervals specified in advance, the magnitude of the change in gas temperature and rotor speed d of the engine for a given period of time, the magnitude of the change is filtered using a first-order aperiodic link with a time constant twenty-five times greater than the specified period of time, the ratio of the filtered magnitude of the change in gas temperature to the filtered magnitude of the change in the frequency of rotation of the engine rotor is calculated if the ratio exceeds the predetermined value for a predetermined time, generate a signal "Dangerous engine operation" and stop the fuel supply to the engine for a time of 0.3 ... 0 , 5 seconds, RF patent No. 232,388 of July 20, 2008

The disadvantage of this method is the following. In the take-off mode of the aircraft, in the event of a failure in the gas temperature measuring channel, which leads to an overestimation of the measured temperature relative to true, an unlimited decrease in fuel consumption in the compressor station and, as a result, loss of engine thrust is possible, which reduces its reliability as the main element of the aircraft power plant safety of the aircraft itself.

The aim of the invention is to improve the quality of ACS and, as a result, increase the reliability of the engine and the safety of the aircraft.

This goal is achieved by the fact that in the method of protecting a gas turbine engine, namely, that the temperature of the gases behind the turbine is measured, its value is compared with the set value, if the measured temperature of the gases exceeded the set value, the fuel consumption in the gas turbine combustion chamber (CC) is reduced until until the measured temperature of the gases becomes less than a predetermined value, in the engine start-up mode at equal intervals of time specified in advance, the magnitude of the change in gas temperature and engine rotor speed is calculated for a given period of time, the magnitude of the change is filtered using a first-order aperiodic link with a time constant twenty-five times greater than the specified period of time, the ratio of the filtered magnitude of the change in gas temperature to the filtered magnitude of the change in the rotor speed of the engine is calculated if the ratio exceeds the predetermined value in advance during a predetermined time, generate a signal "Dangerous engine operation" and stop the fuel supply to the engine for a time of 0.3 ... 0.5 seconds, additionally, depending on the position of the throttle throttle, flaps and parking brake of the aircraft, the engine turbocharger speed, a take-off mode (BWR) signal is generated, the minimum permissible value of the turbocompressor speed is formed by the throttle position, the minimum permissible speed value and the measured mismatch are compared used as a control error to control fuel consumption in the compressor station until the BVR signal is removed.

The drawing shows a diagram of a device that implements the inventive method.

The device contains a series-connected sensor unit 1 (DB 1), an electronic controller 2 (RED 2), a fuel metering unit 3 (DT 3), a fuel shut-off valve 4 (KO 4), and DT 3 is connected to BD 1, and KO 4 - to ER 2, signal board 5 "Dangerous engine operation", connected to ER 2.

RED 2 is an on-board digital computer (BCM), which contains read-only memory (ROM), which contains software (software) that implements engine control algorithms. Additionally, the digital computer is equipped with input / output devices (I / O) of physical signals (from DB 1 and DT 3), random access memory (RAM), which is necessary for the processor to process information coming from the air-blast computer, a programmable memory device (RPZU), which is required to store information, related to the individual characteristics of the engine (operational adjustments, operating hours, remaining life). A computer, ROM, software, air-blast, RAM, processor, RPM are not shown in the drawing.

The device operates as follows.

In RED 2, using DB 1, the temperature of the gases behind the turbine is measured and its value is compared with the set value stored in the ROM (for the PS-90A2 engine manufactured by Aviadvigatel OJSC, Perm, the set temperature of the gases behind the low-pressure turbine is 855 K). If the measured gas temperature has exceeded the set value, by the command of the RED 2 using DT 3 reduce the fuel consumption in the compressor until the measured temperature of the gases becomes less than the set value.

Additionally, at engine start mode in RED 2:

- at equal intervals of time specified in advance (for example, for electronic regulators RED-90 included in self-propelled guns of PS-90A engines, this interval is 0.02 seconds), the magnitude of the change in gas temperature and frequency of rotation of the rotor of the engine for a given period of time is calculated;

- the magnitude of the change is filtered using the first-order aperiodic link with a time constant ten times larger than the specified time period (for PS-90A engines this constant is 0.5 seconds);

- calculate the ratio of the filtered magnitude of the change in gas temperature to the filtered magnitude of the change in rotational speed of the engine rotor;

- compare the ratio with a predetermined value (for PS-90A engines this value is 0.48 K x second);

- if the ratio exceeds the predetermined value in advance for the predetermined time (for PS-90A engines this time is 0.5 seconds), a signal is generated on the display 5 “Dangerous engine operation” and is stopped for 0.3 ... 0.5 seconds the fuel supply to the engine KS, including KO 4.

Usually this is enough to stop the increase in gas temperature, which is dangerous for the gas generator, and the engine starts to work normally.

Additionally, in RED 2, depending on the position of the throttle, the flaps and the parking brake of the aircraft, the engine turbocharger speed (all this information is received in the RED 2 from the OBD 1), the “Take-off mode” (BVR) signal is generated, which is issued from the RED 2 to the recording equipment aircraft (not shown).

A BVR signal, for example, on a Tu-204SM aircraft with PS-90A2 engines, is generated when the following conditions are met:

- α _ores ≥58 ° (position of the _ore ),

and

- the absence of the “Flaps removed” signal

and

- the presence of the signal "Parking brake is off",

and

- n vd ≥ 12055 rpm (engine turbocharger speed).

If there is a BVR signal in RED 2, the minimum permissible value of the speed of the turbocompressor is formed according to the position of the ORE, the minimum permissible value of the rotational speed is compared and the measured, obtained mismatch before the signal is taken, the BVR is used as a control error to form a control action on the DT 3, the position of which determines the amount of fuel consumption in the COP.

Thus, by improving the quality of engine control during take-off, the engine is protected from failures in the engine control equipment, leading to a decrease in fuel consumption in the compressor station and, as a result, loss of engine thrust.

This increases the reliability of the SU and the safety of the aircraft.

Claims (1)

A method of protecting a gas turbine engine (GTE), which consists in measuring the temperature of the gases behind the turbine, comparing its value with the set value, if the measured gas temperature has exceeded the set value, reducing the fuel consumption in the gas turbine combustion chamber (КС) until the measured temperature of gases does not become less than a predetermined value, in the engine start-up mode at equal time intervals specified in advance, the magnitude of the change in gas temperature and the rotor speed of the engine rotor for a given period of time is calculated, the causes of change are filtered using a first-order aperiodic link with a time constant twenty-five times greater than a given period of time, the ratio of the filtered magnitude of the change in gas temperature to the filtered magnitude of the change in the frequency of rotation of the engine rotor is calculated if the ratio exceeds a predetermined value for a predetermined time , generate a signal "Dangerous engine operation" and stop the fuel supply to the engine for a time of 0.3 ... 0.5 s, characterized in that it is additionally depending on the position of the engine control lever (ORE), the flaps and the parking brake of the aircraft, the engine turbocharger speed generate a “Take-off mode” (BWR) signal, the minimum permissible value of the turbocharger speed is formed by the position of the ORE, the minimum allowable speed value and the measured , the resulting mismatch is used as a control error to control the fuel consumption in the compressor station until the BVR signal is removed.

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