Optimization Design For TPS Calibration Facility Control System

At present,the most advanced wind tunnel test method of power impact is to install turbine power simulator in engine model nacelle.The simulated nacelle in this wind tunnel is called TPS(turbofan powered simulator)nacelle.Before TPS nacelle is used in wind tunnel test,its flow coefficient and velocity coefficient must be calibrated in TPS calibration Facility.To carry out the high-precision calibration test of TPS nacelle,the stability,rapidity and accuracy of the control system are required.However,the previous TPS calibration Facility control system has some shortcomings,for example,it is prone to flow impact phenomenon,can not achieve optimal control,and the suppression of air source pressure disturbance is relatively sluggish.The research content of this paper focuses on how to solve these problems by optimizing the control system algorithm.Specifically,the main research contents are as follows:(1)Model identification and whole system simulation of air supply and exhaust system of TPS calibration FacilityFirstly,the high-pressure air supply system and vacuum exhaust system of TPS calibration Facility are modeled,and the whole system simulation of air supply and exhaust of TPS calibration Facility is realized in MATLAB based on the calibration process and the balance state of air supply and exhaust of calibration Facility,which provides a simulation verification platform for subsequent transplantation and parameter tuning of other algorithms.At the same time,the genetic algorithm is used to realize the global parameter optimization of the whole system,which provides a powerful tool for parameter tuning of subsequent transplantation of other algorithms.(2)Research on the mechanism of flow impact and its suppression algorithm.Firstly,the working principle and characteristics of digital valve are analyzed.After establishing the mathematical model of digital valve,the flow impact characteristics of different digital valve codes are studied,and the flow impact phenomenon is reproduced through simulation.In order to suppress the flow impact,it is verified by experiments that asynchronous switching can effectively suppress the flow impact phenomenon.Therefore,an asynchronous switching controller for digital valves is designed.After the desired valve position is given by the control algorithm,the current valve position and the target valve position are switched asynchronously,which effectively solves the flow impact phenomenon caused by the asynchronous opening and closing process of digital valves.Finally,the method is verified by experiments.(3)Optimization of control algorithm and control strategy.There are some defects in the variable PID parameter algorithm used in the system before.This paper mainly optimizes the control algorithm and control strategy to improve the rapidity,stability and accuracy of the system.Aiming at the control algorithm,this paper mainly designs the control structure of generalized predictive controller and disturbance feedforward controller,and achieves good control effect.Aiming at the control strategy,firstly,a piecewise predictive control strategy based on the characteristics of digital valves is proposed to increase the speed of the system,and at the same time,the wear of digital valves is also reduced.Secondly,a control strategy of flow oscillation at the target point is proposed,through which this oscillation phenomenon can be suppressed.