RU2527850C1 - Method of control over gas turbine engine compressor actuators - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: microprocessor complex processes data supplied by transducers of pressure at compressor inlet and outlet, gas temperature behind the combustion chamber, rotor angular rpm and instantaneous fuel flow rate. First derivatives of measures parameters and their threshold magnitudes are calculated. Majority definition of surging start is carried out by comparison of measured parameter derivatives with their thresholds. Surging start signal is generated and transmitted to blow-in control systems.

EFFECT: improved possibility of valid and fast determination of surging under whatever engine operating conditions.

2 cl, 1 dwg

Description

The invention relates to the field of engine engineering and can be used for reliable and timely diagnosis of surging gas turbine engine (GTE), and allows to eliminate the unstable mode of operation of the compressor by the operational impact on various engine control systems. The method for diagnosing surging includes measuring the angular velocity of the turbine rotor, measuring the air pressure at the inlet and outlet of the compressor, measuring the instantaneous fuel consumption and measuring the color temperature behind the combustion chamber.

A known method for diagnosing compressor surge [US patent No. 25178801, G01M 15/00, April, 1978], in which the temperature of the gases in front of the turbine and the rotor speed of the compressor rotor are measured. Since when the flow stalls in the compressor, the temperature of the gases in front of the turbine increases and the rotor speed decreases, the conclusion about the development of surge in the compressor is made if the threshold value for the ratio of the gas temperature in front of the turbine to the rotor speed is exceeded.

The disadvantage of this method is that the ratio of the temperature of the gases in front of the turbine to the rotational speed of the rotor can exceed the threshold value when changing the operating mode of the engine, for example during throttling, on the basis of which a false conclusion can be made about the presence of surge. The disadvantages include the inertia and vulnerability of the method in case of failure of one of the sensors.

A known method for the diagnosis of surge compressor [Chigrin B.C. The design of the turboshaft gas turbine engine D-136. Kharkov: HVVAIU, 1989. - 143 pp.], At which the pressure behind the compressor is measured, the magnitude of the pressure change behind the GTE compressor is calculated, which is determined as the time derivative of the pressure behind the compressor, and if the threshold value is exceeded, a conclusion is drawn about the development of surge compressor.

The disadvantage of this method is that it allows you to determine the presence of surge even at the actual onset of surge operation of the compressor, since the threshold value is set high enough (in the example, it is 8 s ^-1 ). Lowering the threshold value for an earlier diagnosis of surging can lead to false conclusions about the presence of surging when changing engine operating modes (for example, when the gas is released, the pressure behind the compressor also decreases).

Also known is a method for diagnosing compressor surge [RF patent No. 2263234 C1, F04D 27/02, publ. 10.27.2005], in which the inlet pressure, the pressure behind the compressor and the rotor speed are measured, the signs and magnitude of the time derivatives of these parameters are determined, each derivative is compared with its threshold value. The conclusion about the presence of surge development is made if the derivatives exceed their threshold values. Since the change in parameters can occur with a time shift, when the threshold value of one derivative is exceeded, they are expected when the values of the other derivatives exceed their threshold values, and only then do they conclude that there is a surge. This method allows to make a conclusion about the development of surge during the first surge fluctuation.

However, when using this method for an aircraft gas turbine engine, in case of a change in the operating mode, for example, during gas discharge, the pressure derivatives behind the compressor and the rotor speed can also exceed their threshold values. The third parameter - the pressure at the inlet to the compressor, is not indicative, since it depends not only on the operating mode of the engine, but also on a large number of factors determined by the altitude and speed of the aircraft. Therefore, when using this method for an aircraft gas turbine engine, false conclusions about the presence of surge can also be obtained.

Closest to the proposed method is the method [RF patent No. 2187711, IPC F04D 27/02, publ. 08/20/2002 / Inozemtsev A.A. etc. A method for diagnosing surging of a compressor of a gas turbine engine], which consists in measuring the brightness temperature of the surface of the turbine rotor blade and its first two derivatives with a brightness pyrometer, comparing temperature parameters with their threshold values, additional measuring pressure behind the compressor and its first derivative, comparing pressure parameters with their threshold values and the formation of a signal about the onset of surge, with the simultaneous output of the first derivatives of brightness temperature and pressure beyond the compress rum for their threshold values.

The disadvantages of this method include the inertia of the temperature measurement associated with the time delay of heating the surface of the rotor blades; the possibility of generating a false signal about the onset of surge during non-stationary operating modes, for example, when switching from the nominal mode to the “low gas” mode; the possibility of generating a false signal about the onset of surge due to a failure of the cooling system of the working surfaces of the gas turbine engine.

The problem solved by this invention is to increase the reliability of determining the onset of surge in all modes of operation.

The technical result of this invention is to increase the reliability of determining the onset of surge in all modes of operation.

The problem is solved, and the technical result is achieved by the fact that in the method for diagnosing surging compressor of a gas turbine engine, which consists in measuring the temperature behind the combustion chamber and calculating its first derivative, measuring the air pressure in the compressor and calculating its first derivative, comparing the derivatives of the measured parameters with their threshold values and determining the surge, when several derivatives go beyond threshold values, in contrast to the prototype, they additionally measure the pressure difference at the outlet and inlet of the comp the engine spring and calculate its first derivative, measure the instantaneous fuel consumption and calculate its first derivative, measure the angular velocity of the rotor of the engine turbine and calculate its first derivative, calculate the threshold values of the first derivatives of the temperature of the combustion chamber, the pressure difference at the outlet and inlet of the engine compressor, angular the rotational speed of the rotor of the engine turbine and by comparing the first derivatives of the temperature of the combustion chamber, the pressure difference at the outlet and inlet of the engine compressor, angular the rotational speed of the rotor of the engine turbine with their threshold values, produce a majority vote by which the surge is judged.

Distinctive features of the method are the measurement of the first derivatives of the gas temperature ∂Т / ∂t, the pressure difference at the compressor inlet and outlet ∂ΔР / ∂t, the angular velocity of the turbine rotor shaft ∂ω / ∂t and their comparison with their threshold values: [∂T / ∂t], [∂ΔР / ∂t], [∂ω / ∂t], respectively, functionally dependent on the instantaneous fuel consumption G. During the start of surge, the first derivatives of these parameters go beyond the threshold value. For a majority vote, the conditions for the first derivatives to exceed their threshold values are used. (∂T / ∂t> [∂T / ∂t], ∂ΔР / ∂t <[∂ΔР / ∂t], ∂ω / ∂t <[∂ω / ∂t].) To generate a signal about the beginning of surge it is enough to go beyond the threshold values of the derivatives of two parameters. If one of the sensors fails, the information remaining is sufficient to generate a surge onset signal, which increases the reliability of the method. If one of the sensors fails, its information is not enough to generate a surge onset signal, which increases the reliability of the method signal. With an increase in the instantaneous fuel consumption in the safe condition of the gas turbine engine, an increase in the gas temperature T, an increase in the angular velocity of the rotor of the gas turbine turbine ω, and an increase in the pressure difference at the compressor inlet and outlet ΔР increase.

The invention is illustrated in the drawing. In FIG. shows a device that implements the method.

Concrete implementation example

The inventive method is implemented by the diagnostic device surge surge compressor of a gas turbine engine. The device comprises: an instantaneous fuel consumption sensor 1, a pressure sensor at the inlet of the compressor 2, a pressure sensor at the outlet of the compressor 3, an angular rotational speed sensor for the turbine turbine engine 4, a spectral ratio pyrometer 5 connected to a microprocessor system 6 connected to an anti-surge control system 7. The pyrometer of the spectral ratio 5 is positioned so as to measure the temperature of the gas behind the combustion chamber.

According to the method, the sensor of instantaneous fuel consumption 1, pressure sensors at the outlet and inlet to compressors 2 and 3, the angular velocity sensor of the turbine rotor 4 and the spectral ratio pyrometer 5 transmit the measurement results to the microprocessor system 6, which calculates the pressure difference at the inlet and outlet ΔР, the first derivatives measured parameters ∂Т / ∂t, ∂ΔР / ∂t, ∂ω / ∂t, ∂G / ∂t. Based on the sign of the derivative of the instantaneous fuel consumption, the current engine operation mode is determined: an increase in fuel consumption, a constant fuel consumption and a decrease in fuel consumption. With an increase (decrease) in instantaneous fuel consumption in non-surge modes of engine operation, the parameters T, ΔР and ω respectively increase (fall) and remain unchanged at a constant instantaneous fuel consumption. The occurrence of surging is determined by various external factors and does not depend on the current fuel consumption, and is accompanied by an increase in temperature and a decrease in the angular velocity of rotation of the turbine rotor and the pressure difference at the inlet and outlet of the compressor. The use of the color temperature of the gas in the combustion chamber can significantly reduce the time delay of the temperature measurement behind the combustion chamber in connection with the practical inertia of the gas, compared with the design elements of the gas turbine engine. The use of the difference in pressure at the inlet and outlet of the compressor is a more indicative parameter than the pressure at the outlet of the compressor, since it allows you to take into account atmospheric pressure and avoid introducing additional errors associated with threshold values and atmospheric pressure. The threshold values [∂Т / ∂t], [∂ΔР / ∂t], [∂ω / ∂t] depend on altitude, flight speed, instantaneous fuel consumption, and geometric characteristics of the engine and are calculated programmatically from functional dependences obtained experimentally. For a majority vote, the conditions for the first derivatives to exceed their threshold values are used. (∂T / ∂t> [∂T / ∂t], ∂ΔP / ∂t <[∂ΔP / ∂t], ∂ω / ∂t <[∂ω / ∂t].) To generate a signal about the beginning of surge it is enough to go beyond the threshold values of the derivatives of two parameters.

Claims (2)

1. A method for diagnosing a surge of a compressor of a gas turbine engine, which consists in measuring the temperature behind the combustion chamber and calculating its first derivative, measuring the air pressure in the compressor and calculating its first derivative, comparing the derivatives of the measured parameters with their threshold values and determining the surge when several derivatives exceed the threshold values, characterized in that they additionally measure the pressure difference at the outlet and inlet of the engine compressor and calculate its first derivative, measure mg new fuel consumption and calculate its first derivative, measure the angular velocity of the rotor of the engine turbine and calculate its first derivative, calculate the threshold values of the first derivatives of the temperature of the combustion chamber, the pressure difference at the outlet and inlet of the engine compressor, the angular velocity of rotation of the rotor of the engine turbine and by comparing the first derivatives of the temperature of the combustion chamber, the pressure difference at the outlet and inlet of the engine compressor, the angular velocity of rotation of the rotor of the engine turbine with their threshold values niyami make majority voting on which is judged on the early surge. 2. The method according to claim 1, characterized in that the color temperature of the gas is measured behind the combustion chamber.

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