RU2379534C2 - Method to control gas turbine engine - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: proposed invention can be used in electronic-hydromechanical automatic control systems (ACS) of gas turbine engines (GTE). It consists in controlling mismatch between preset and measured values of the position of guide vanes. If said mismatch exceed preset value selected proceeding from engine test for compressor gasdynamic stability, fuel consumption rate is limited.

EFFECT: higher quality of ACS operation and GTE reliability, as well as safety of aircraft.

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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).

There is a known method of controlling a gas turbine engine, which consists in the fact that according to the measured position of the engine control lever (ORE), the fuel consumption in the combustion chamber (KS) is controlled, and the air bypass valves are controlled by the compressor according to the measured rotor speed of the engine, [1].

The disadvantage of this method is its low efficiency in terms of providing the required reserves of gas-dynamic stability (GDU) of the compressor and, as a result, the inability to use modern gas-turbine engines, namely turbojet engines with a high bypass ratio (TRD), such as, for example, the family of engines PS-90A.

Closest to this invention in technical essence is a gas turbine engine control method, which consists in the fact that a control action is formed from the measured position of the engine control lever (ORE), the measured rotational speed of the engine rotor, the measured temperature of the gases behind the engine turbine, and the measured air pressure behind the engine compressor the fuel consumption in the COP, the measured frequency of rotation of the rotor of the engine and the air temperature at the inlet of the engine form the value of the reduced frequency of rotation of the rotor engine

form a predetermined position of the blades of the guide vane (HA) of the engine compressor, compare it with the measured position of the blades of the HA, the magnitude of the mismatch between the set and measured values form the control action on the drive of the blades of the HA, [2].

The disadvantage of this method is the following.

In case of failure of an ACS element, for example, an electrohydroconverter, forming a hydraulic command for shifting the hydraulic cylinders of the drive blades of the HA, the correspondence between the available fuel consumption in the engine's CS and the required air flow through the engine’s gas-air duct is violated.

This can lead to the overthrow of the gas generator parameters (for example, the gas temperature in front of the turbine) or to the loss of gas-dynamic stability of the gas turbine compressor - surging.

This, in turn, leads to a decrease in the reliability of the gas turbine engine and, as a consequence, to a decrease in the flight safety of the aircraft.

The aim of the invention is to improve the quality of work of self-propelled guns and, as a result, increase the reliability of a gas turbine engine and the safety of an aircraft.

This goal is achieved by the fact that additionally control the amount of mismatch between the set and measured values of the position of the blades of the HA, if the mismatch exceeds the set value determined in advance by the results of engine tests for the gas-dynamic stability of the compressor, limit the rate of change in fuel consumption.

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

The device contains a series-connected sensor unit 1, a setter 2 of the engine operation mode, a first adder 3, a first electrohydraulic converter 4, a fuel meter 5, a second input of an adder 3 connected to a block 1, a series ON switch 6, a second adder 7, a second electro-converter 8, the control valve 9 of the ON, the switch 6 and the second input of the adder 7 are connected to the block 1, the output of the adder 7 is connected to the switch 2.

The device operates as follows.

According to the position of the engine control lever (ORE), measured with the help of block 1, the rotor speed of the engine, the temperature of the gases behind the engine turbine, the air pressure behind the engine compressor, the setpoint 2 forms the set position of the dispenser 5, which in the adder 3 is compared with the actual position measured with unit 1. By the magnitude of the mismatch entering the electrohydroconverter 4, a control action is formed on the dispenser 5, with which the fuel consumption in the compressor station is changed.

According to the measured at the engine inlet air temperature and the engine rotor speed measured using the unit 1, the setter 6 generates the value of the reduced rotor speed of the engine and forms the desired ON position for this engine operation mode.

The predetermined position of the HA enters the adder 7, where it is compared with the measured position of the HA (from block 1). According to the magnitude of the mismatch between the set and measured values of ON, the electrohydroconverter 8 controls the ON using the spool 9.

With serviceable elements of the control circuit of the ON (electrohydroconverter 8, spool 9), the actual position of the ON differs from the set practically only in dynamic modes. Because Since the preset position of the ON is determined by the reduced speed of rotation, which changes smoothly, the size of the mismatch between the preset and actual position of the ON in a dynamically debugged system does not exceed 2-3% in terms of speed. However, in operation there are situations when the amount of mismatch at certain moments can exceed this value (for example, during “mashing” of the hydraulic cylinders of the HA drive, at the time of a sharp increase in the required fuel consumption, when the inertia of the fuel pump does not allow an instantaneous increase in the available flow rate, etc. ) This creates an imbalance between the air flow rate through the engine compressor and the fuel consumption in the compressor station. To avoid this, the amount of mismatch between the set and the actual position of the ON from the output of the adder 7 is supplied to the control unit 2 for monitoring: if the set value determined during the acceptance tests of the engine is exceeded in advance, the control unit 2 begins to limit the rate of change in fuel consumption.

T.O. a balance is maintained between the air flow through the engine compressor and the fuel consumption in the compressor station. This provides an increase in the quality of the ACS and, as a result, an increase in the reliability of the gas turbine engine and the safety of the aircraft.

SOURCES OF INFORMATION

1. Cherkasov B.A. Automation and regulation of the WFD. M., Mechanical Engineering, 1965.

2. Shlyakhtenko S.M. Theory of aviation WFD. M., Mechanical Engineering, 1974.

Claims (1)

A method for controlling a gas turbine engine, namely, according to the measured position of the engine control lever (ORE), the measured rotational speed of the engine rotor, the measured temperature of the gases behind the engine turbine, the measured air pressure behind the engine compressor, a control effect on the fuel consumption in the compressor station is formed, according to the measured the rotor speed of the engine rotor and the air temperature at the inlet of the engine form the value of the reduced frequency of rotation of the engine rotor, form the specified position of the blades n the control unit (ON) of the engine compressor, compare it with the measured position of the blades of the HA, according to the size of the mismatch between the set and measured values, form a control action on the drive of the blades of the ON, characterized in that they additionally control the amount of mismatch between the set and measured values of the position of the blades of the HA, if the mismatch exceeds the predetermined value determined in advance by the results of the engine’s tests for the compressor’s gas-dynamic stability reserve, limit the pace and changes in fuel consumption.

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