Auxiliary power device intake valve control system and method

Abstract

The invention belongs to the field of auxiliary power device control, particularly relates to an auxiliary power device intake valve control system and method. The problem that in air state, the airflow entering the APU is extremely unstable due to high Mach number and lower inlet pressure of the APU, and the APU is unsuccessful in ignition can be solved. When an APU main switch of a cockpit is pressed down, an ECU is powered on, and in the ground state, after an APU starting instruction is received, an air inlet valve is directly and fully opened, and then the APU is started. However, in theair state, the ECU gradually opens the intake valve according to a predetermined function relationship f (Ma, N, P2) with the flight Mach number, the APU rotating speed and the APU inlet pressure, sothat the air flow entering the APU is relatively stable. According to the invention, the opening or closing of the APU intake valve can be accurately controlled, and the opening degree can be controlled, so that the air inflow entering an APU combustion chamber is adjusted, the success rate of APU ignition is remarkably improved, and the method can be applied to the control of the APU intake valvewith wide flight envelope and complex use working conditions.

Description

technical field [0001] The invention belongs to the field of auxiliary power unit control, and relates to gas turbine engines, especially the control of the intake valve of the auxiliary power unit. Background technique [0002] The auxiliary power unit (Auxiliary Power Unit, referred to as APU) is the auxiliary power source of the aircraft, and its core unit is a small centrifugal gas turbine engine. It is mainly used to provide bleed air for the starting of the main engine of the aircraft and the environmental control system, and can provide shaft power for the aircraft power generation system through the accessory gearbox. When the aircraft is on the ground, the APU can replace the bulky air source vehicle and power supply vehicle; during the take-off process of the aircraft, the use of the APU can make all the power of the main engine used to accelerate the climb, so as to improve the performance of the aircraft take-off; after the aircraft lands, use APU, the main engi...

AI Technical Summary

Problems solved by technology

[0006] The purpose of the present invention is to propose a new auxiliary power unit intake valve control method to overcome the extremely unstable airflow entering the APU due to the high Mach number and low APU inlet pressure in the air state, thus causing APU The problem of unsuccessful ignition, in the present invention, when the "APU main switch" of the cockpit is pressed, the ECU is powered on, and in the ground state, after receiving the APU start command, the intake valve is also directly fully opened, and then start APU

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