Temperature control method of wave-absorbing external heat flow simulation system for large-scale spacecraft antenna performance test

Abstract

The invention discloses a temperature control method of a wave-absorbing external heat flow simulation system for a large-scale spacecraft microwave antenna vacuum thermal test, surface temperature of a wedge inside a wave-absorbing box is used as a controlled object, and a thin film heater on the outer surface of the wave-absorbing box serves as a heater, thereby realizing temperature control of an antenna arranged inside the wave-absorbing box. According to the method, on the basis of a multistage PID algorithm, a stable-state and dynamic model of wave-absorbing material surface temperature-antenna surface arrived heat flow is established to set ratio parameters, integral parameters and differential parameters at different temperatures; algorithm target curves are given in a segmented manner; a fuzzy control algorithm is adopted to improve the balancing speed of the controlled object; and a neural network model is introduced to predict the test piece surface temperature. The temperature control method of the wave-absorbing external heat flow simulation system for the large-scale spacecraft microwave antenna vacuum thermal test realizes uniformity and high-efficiency and high-precision control of antenna temperature in a large-scale spacecraft microwave antenna thermal test, is suitable for a large-scale microwave antenna vacuum thermal test, improves test effectiveness and coverage of the test, and is also suitable for a vacuum thermal test of a spacecraft equipped with a large-scale microwave antenna.

Description

technical field [0001] The invention belongs to the field of ground vacuum thermal test of large-scale microwave antennas of spacecraft. Specifically, the invention relates to a method for controlling the temperature of a microwave-absorbing external heat flow simulation system used for vacuum thermal tests of large-scale microwave antennas of spacecraft on the ground. It is used to improve the temperature control accuracy and efficiency of simulating antenna heat flow outside orbit. Background technique [0002] The spacecraft vacuum thermal test is a test to verify various performances and functions of the spacecraft under specified vacuum and thermal cycle conditions. It is one of the important tests in the multi-environmental simulation tests in the development stage of the spacecraft. The main purpose of the test is to expose the spacecraft’s material and manufacturing process defects under vacuum and thermal cycle conditions, and eliminate early failures, thereby grea...

AI Technical Summary

Problems solved by technology

[0007] (1) Since the characteristics of the controller and the absorbing material are different at different temperatures, and the heat capacity of the absorbing material is large, the control algorithm using fixed parameters will cause control overshoot and oscillation

[0008] (2) Since the heat flow simulation system outside the absorbing wave is a hierarchical control system, the control system realizes the temperature control of the control target by achieving thermal balance between the actual control object and the control target. This process has a large time lag. And there is a certain temperature difference between the two during the control process

In order to avoid overshooting of the control target, the existing temperature control method can only manually predict the temperature difference between the two, and set a safe target temperature according to the predicted temperature difference. When the actual control object reaches the set target temperature Then, according to the temperature difference between the actual control object and the control target at this time, adjust the next control target temperature

[0009] (3) The temperature control efficiency is low and the time is long during the test

As a result, the quality of the test cannot be fundamentally guaranteed

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