压电比例阀调节的氙气微推进系统流量特性仿真研究

Simulation Study on Flow Characteristics of a Xeon Micro Propulsion System under Regulation of Piezoelectric Proportional Valve

关键词:  无拖曳卫星  氙气微推进系统  AMESim仿真  流量特性

Key words:  Drag-free satellites  Xenon gas micro propulsion system  AMESim simulation  Flow characteristic

摘要:

基于压电比例阀驱动的氙气微推进系统是目前国际的发展趋势。压电比例阀作为该类型推进系统的核心组件，其性能将直接影响系统流量特性和推力。本文首先采用AMESim软件对某型氙气工作压力为0.3MPa的压电驱动氙气微推进系统进行建模，并对系统填充过程中的气瓶与减压阀工作特性进行分析。然后研究了不同减压阀反馈腔压力条件下的减压阀与压电比例阀的阀芯运动和氙气质量流量特性。最后，分析了压电比例阀驱动电压对开机过程中的压电比例阀阀针位移、氙气质量流量特性的影响规律。结果显示，压电比例阀阀针在通电后迅速开启，其最终的稳定升程为3.7μm。系统的氙气质量流量的稳定值为5.63mg/s。减压阀反馈腔内的氙气压力越大，压电比例阀开启后的氙气质量流量稳定值越大且响应时间越长。仿真结果表明，本次研究的氙气微推进系统可以通过改变驱动电压实现对氙气质量流量的线性调节，系统氙气质量流量可在较短时间内达到目标值。

Abstract:

Xenon micro propulsion system under the regulation of the piezoelectric valve is the development trend in the world. Working performance of the piezoelectric proportional valve, which is the core component for this type of propulsion system, has a great influence on the flow characteristics and thrust force of the system. Firstly, a mathematical model was established using AMESim software to describe a xenon micro propulsion system with a xenon working pressure of 0.3MPa. Working characteristics of the gas tank and pressure reducing valve in the filling process of the system were analyzed. Then, the kinetic characteristics of the valve core and xenon mass flow rate of the pressure reducing valve and piezoelectric proportional valve under different gas pressures within the feedback cavity of the pressure reducing valve were investigated. Finally, the effects of the driving voltage of the piezoelectric proportional valve on the needle displacement and xenon mass flow rate were analyzed. The results indicated that the needle of piezoelectric proportional valve was quickly opened, and it’s lift in the stable stage was 3.7 μm. The stable value of xenon mass flow in the system was 5.63mg/s. The greater the xenon pressure within the feedback cavity of the pressure reducing valve, the larger the mass flow stability value and the longer the response time after the piezoelectric proportional valve opened. The simulation results show that linear regulation of xenon mass flow can be realized by changing the driving voltage in a xenon micro propulsion system analyzed in this study. The xenon mass flow rate of this system can reach the target value in a short period of time.