MATCHING OF THE AUXILIARY COMPRESSOR CONTROL CIRCUIT WITH THE FUEL CONTROL CIRCUIT TO PROVIDE GAS-DYNAMIC STABILITY OF THE APU TURBOCOMPRESSOR

Y.V. Pavlyuk, S.V.Yepifanov, S.I. Sukhovey, R.L. Zelensky

The analysis of the impact of the operation of the APU auxiliary compressor control circuit on the combustion chamber fuel control circuit in the system with the use of the fuel from the fuel metering pump to control the compressor is given. With the use of the developed model of the system it was found that in the case of the instant stop of the compressor control actuator’s output link the short-term increase of the fuel supply to combustion chamber takes place that leads to decrease of the gas-dynamic stability factor of the APU turbo-compressor. On the base of the simulation of the system the guidelines on the compressor control algorithm were given. The required gas-dynamic stability factor is provided by the choice of the appropriate deceleration before the stop of the actuator’s output link. The results of the investigation were used during the development of the control system of the APU ÀÈ-450-ÌÑ.

Key words: APU, auxiliary compressor, compressor control units, compressor control algorythm, gas -dynamic stability factor.