微电推进贮供系统开发与系统级仿真研究

Development and System-Level Simulation of Micro Electric Propulsion Feeding System

关键词:  微电推进贮供系统  氪气  PEEK毛细管  微流量控制  系统级一维瞬变模型

Key words:  Micro electric propulsion feeding system  Krypton  PEEK capillary  Micro flow control  System-level one-dimensional transient model

摘要:

针对传统电推进贮供系统应用于微小卫星任务时重量和体积庞大的问题，提出一套小型化、轻质化、低成本的微电推进贮供系统设计方案并进行了开发工作。采用聚醚醚酮复合材料（PEEK）制作的毛细管替代金属毛细管用于微流量控制，以氪气为工质进行试验，验证了其能够在±1%控制精度内实现0.0291~0.4145 mg/s的稳定流量输出。本文在Amesim中构建系统级一维瞬变模型，进行微电推进贮供系统仿真，并与试验结果对比验证模型的有效性与准确性。对仿真结果进一步分析阐述了系统从启动到稳定工作过程中压强超调、稳定段流量波动等工作特性以及减压器弹簧及膜片刚度、毛细管内径等关键参数的影响规律，通过对各部件热力状态参数动态变化的分析揭示了工质气体向下游供给过程中流动、传热与控制耦合作用的物理机制。

Abstract:

The traditional electric propulsion feeding system has the problems of huge weight and volume， which is not adapted to micro-satellite missions. In order to solve these problems， a small， light and low-cost micro electric propulsion feeding system was designed and built. The capillary made of composite PEEK is used to replace the metal capillary for micro flow control. The experiment with Krypton as working gas verified that it can provide a stable mass flow of 0.0291~0.4145mg/s within ± 1% control accuracy. Secondly， the system-level one-dimensional transient model was constructed in Amesim for simulation of the micro electric propulsion feeding system. The comparison between simulation and experiment results verified the effectiveness and accuracy of the model. The further analysis of the simulation results illustrated the operating characteristics of the system from opening section to stable section， such as pressure overshoot， flow fluctuation in the stable section， and the influence of the key parameters such as the spring and diaphragm stiffness of the pressure reducer， and the inner diameter of the capillary. Through analysing the dynamic changes of the thermal state parameters for each component， the physical mechanism of the coupling effect of flow， heat transfer and control in the process of the supply of working gas to the downstream was revealed.