Control systems TRDTS

Bilge pump switched off after stopping the engine to drain the oil chamber. Total capacity of these pumps must be 2. .3 Times greater than the pumping performance of the pump as they are pumped out of the oil chamber of oil mixture with air.

Necessary for the development of the "electric" turbine engine technology should allow the creation of:

- electric drives with specific gravity <0,5. 0,8 kg / kW;

- high-speed electric generators (with a rotation frequency of up to 30000 rpm, a voltage of 270 V, a capacity of up to 540 kW),

- highly integrated heat-resistant (£ slave> 125 ° C) element base, including power, with a failure rate;

- magnetic bearings;

- Smart sensors and Smart actuators.

The state of development of these technologies can count on

the possibility of implementing the systems considered in the short term.

Construction of automatic control systems GTD

Automatic control systems of modern turbofan performs digital electronic type FADECbez hydromechanical backup regulator or a simple controller of this type, often only for manual control. The system performs the full range of flight conditions and the management constraints limit parameters on all steady and transient modes of operation of the engine, protect the motor against surge, self-monitoring and diagnosis of ACS, control and diagnostics of the engine.

The system operates on the engine existing regulators (factors) fuel in the combustion chamber; the angles of the blades of the compressor BHA; bleed valves of the compressor; damper for controlling the inlet air to cool the turbine and to control clearances in the turbine and compressor, as well as a number of other subsidiary bodies.

The electronic regulator has a centralized structure, usually installed on the engine (for large engines) or on board (for small turbojet engines). It uses an electronic element base with a high degree of integration, high reliability (L <10-8 1 / h) and heat resistance (up to +125 ° C).

Modern methods of management and control provide a solution to problems of adaptive management, integration channels pn-

mation exchange systems of the aircraft, compensation for failure. Fuel systems are generally built on the basis of a centrifugal pump for pumping up the preliminary pressurization and high-pressure gear pump, driven by motor gearbox.

One embodiment of the complex of programs implemented in the control system turbofan can be represented as follows.

Reliability SAU

Reliability ACS must be such that the time between failures, leading to the shutdown of the engine in flight, was up to 106 hours. High scores are required for other types of failures.

Obtaining specified reliability indicators is provided in the system by a set of measures: using the element base and other components that have high reliability; Hardware redundancy in the electronic regulator and its elements (two-channel construction scheme with a separate set of sensors and actuators for each channel); Redundancy of electric power supply (including autonomous generator); Software (built-in system for monitoring and diagnostics of automatic control systems, noise-proof control algorithms); Reservation of engine management programs; Reconfiguration of the structure in case of failures, etc.

The requirements for control precision depend on the complex management programs. In the process of developing a control system determines the optimum combination of requirements for the individual parameters and sensors to implement the necessary accuracy maintain engine thrust, economy, stocks GDU.

Typical permissible errors regulation and restriction of the fundamental parameters of the engine at steady state operation are:

For such a control accuracy error of measurement of basic parameters used in making software and control algorithms shall not exceed for air and gas pressure ± 0,5% of the measured value (IV), the temperature of the air entering the engine ± 0,5. 1% IW gas temperature 6. .10 K speed 0,1% IW position blades BHA ± 0,5%.

In transient operation of the engine automatic control system should ensure regulation (restriction) with a precision needed to meet the requirements of the stability of the workflow engine life and duration management processes.

In the future, management will be carried out on the circuit with a distributed structure based on the Smart (intelligent) sensors and IM. Smart-Sensors iSmart MI-containing microprocessor unit (MP) for conversion and pre-processing of measurement and control are connected to the ACS calculator engine mounted on the engine or on board the aircraft, with the help of digital communication lines. A possible scheme of such a system is shown.

Another trend in the improvement of management systems is the use of TBG "electric" technology in which the drive pumps and mechanization of flow of the engine by means of electric motors. This would simplify the system and reduce the cost of service, reduce development costs, reduce weight and improve a number of other characteristics.

In particular, in the most simple case, this problem is solved by the capacity control of the fuel pump by controlling their rotation speed.

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