Journal of the Korean Society of Propulsion Engineers (한국추진공학회지)

The Korean Society of Propulsion Engineers (한국추진공학회)
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Stability Evaluation for the Thrust Control System of KSLV-II 75-tonf Liquid Rocket Engine

한국형발사체 75톤급 액체로켓엔진 추력제어시스템의 안정성 평가

  • Taekyu Jung (Space Propulsion Research Division, Korea Aerospace Research Institute)
  • Received : 2022.12.01
  • Accepted : 2023.02.15
  • Published : 2023.04.30
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Abstract

In this paper, mathematical models for the thrust control system of KSLV-II 75-tonf liquid rocket engine are introduced. Also the stability of the thrust control system is evaluated. An auto oscillation breaks out under the condition of dead band(ΔP), 0.06 bar and the maximum driving speed, 28.4 deg/s of a thrust control valve. The amplitude and frequency of the auto oscillation are each 0.095 bar and 1.43 Hz. It is proved by simulations that the auto oscillation can be avoided under the slower valve driving speed or the higher dead band than the above conditions.

본 논문에서는 누리호 75톤급 엔진 추력제어시스템의 수학적 모델을 제시하였고 안정성을 평가하였다. 추력제어밸브의 최대 구동 속도인 28.4 deg/s에서 dead band(ΔP)가 0.06 bar일 때, 진폭은 0.095 bar, 주파수는 1.43 Hz인 오토오실레이션이 발생하였다. 상기 조건보다 밸브 구동 속도를 느리게 하거나, dead band를 크게 하면 오토오실레이션을 방지할 수 있음을 해석을 통해 확인하였다.

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References

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