摘要
脉冲等离子体推力器PPT(Pulsed Plasma Thruster)点火安全控制系统是PPT设计中的关键。为方便灵活地控制点火脉冲和工作频率,同时保证安全点火,采用直接有脉宽调制信号PWM(Pulse Width Modulation)输出口的数字信号处理器DSP(Digital Signal Processing)控制PPT的点火,完成了DSP辅助电路、和上位机通讯的串口电路、与PPT高压触发模块(脉冲功率装置)的接口电路以及PPT点火时序控制软件的设计。PPT工作时,点火安全控制系统接收由上位机卫星喷气姿态控制算法产生的点火时刻和点火次数命令,执行点火命令。试验表明,PPT点火安全控制系统能够控制PPT试验样机,使其准确按照时序在频率0～1.67 Hz(波形分辨率最高为6.67 ns)下可靠点火。
This paper is aimed at introducing its research achieve- me, its on the design of the PPT ignition control system, including the applicable software and key circuit subsections, such as the housekeeping power supply for the derivational voltages from the spacecraft power, DSP aecessmy circuits, serial interfaces, etc. In our research, we have adopted DSP （Digital Signal Processing） with PWM （ Pulse Width Modulation） and an interface circuitry with pulsed power device. For the sake of enhancing its functions, the secure ignition control system of pulsed plasma thruster （PPT） has been regarded as the key technology in the design of PPT. In order to provide high specific synchronous impulses with alternating frequency to ensure reliability, digital signal processing （DSP） with pulse width modulation （PWM） are used to produce maximum resolution, that is, 6.67 ns tbr controlling the PPT＇s ignition. The system also comprises software systems like the serial data communications protocols for computer-to- DSP. The system is also equipped with secure sequential algorithm, whose logic circuitry is that, only when DSP sends electrifying signal to the pulsed power device and then DSP receives its response that the inspecting signal, the DSP, begins to send trigger signal to ignite PPT, otherwise it would be impossible to ensure the secure work of PPT. The experiment results of the paper indicate breadboard level components are in the position to provide projected benefits in reliability and low impulse variability （frequency 0- 1.67 Hz） and operational flexibility. In addition, options for each subsection are clearly defined to be able to fully meet the system requirements. Furthermoxe, the computer is made to be able to simulate the spacecraft commands by a micro-pulsing algorithm in calculating PPT energy level and pulse rate for desired average thrust for its further practical applications.
出处
《安全与环境学报》
CAS
CSCD
2007年第6期100-102,共3页
Journal of Safety and Environment
关键词
航空
航天推进系统
火箭发动机
点火安全控制系统
数字信号处理器
PPT试验样机
propulsion system of aviation and aerospace
rocket engine
secure ignition control system
digital signal processing
pulsed plasma thruster test set
