Research On The Key Technology Of Measurement And Control System For Aeroengine Fuel Pump Performance Test

The measurement and control system for performance test of aeroengine fuel pump is an important part of the test system, it can provide necessary test conditions to achieve the anticipated purpose of the experiment. The inlet fuel temperature control and anti-jamming are two key issues in the measurement and control system. While the test-bed running, the pressure, friction, and other aspects of energy loss change into heat, which increase the fuel temperature. High fuel temperature will result in increased leakage and oxidation, which shorten the service life of components and reduced the detection accuracy. In order to ensure the detection accuracy and performance of the test-bed, and have a better simulation about the actually working state of the fuel pump, the test-bed inlet fuel temperature must be controled. There are kinds of electromagnetic interferences in the work environment of the measurement and control system, which can make the signal mixed with noise, affect the accuracy of measurement and control system, and serious interference may cause measurement and control system can’t work normally. In order to suppress interference and improve the accuracy of measurement and control, anti-jamming measures must be taken.This paper is based on the aeroengine fuel pump test-bed design. Focusing on problems of the inlet fuel temperature control method and control system anti-jamming technology, analysis of the characteristics of temperature control system and interference characteristics of measurement and control system are carried out. The intelligent control algorithm, conventional PID control algorithms, hardware and software anti-jamming measures, wavelet denoising methods are studied. The main work contents are as following:(1) The test content and theory of aeroengine fuel pump are analyzed in this paper, with an certain example of aeroengine fuel pump, temperature control system is designed, dynamic and static characteristics of heat exchanger are studied, and the mathematical model of temperature control system is established.(2) For the problem of complex characteristics of inlet fuel temperature control system, the conventional PID control algorithm and intelligent control algorithms are studied, the intelligent PID control algorithms is designed by combining the fuzzy and neural network control with PID control. Simulation results show that the intelligent PID control algorithms has favorable control effect.(3) Based on constitution of the measurement and control system, analysis of the sources of interference and interference characteristics are carried out, introduced the common anti-jamming technology, and the measurements of hardware anti-jamming and software anti-jamming are proposed under the three principals of interference.(4) The wavelet denoising methods are studied, a new threshold function is constructed, and carried out comparative analysis of denoising the flow pulsation signals and other signals with the soft and hard threshold compromise function method, the soft, hard threshold method and denoising method besed on Fourier transform. The results show that wavelet denoising method can get favorable denoising result.