Stability Analysis of Electrical Power Subsystem with Constant Power Loads for CubeSat Applications

  • Alya Yousif AlHammadi

Student thesis: Master's Thesis


With the advances of space exploration vehicles that consist of payloads and subsystems, the most crucial one is the Electrical Power Subsystem (EPS) as it is responsible to provide power to the payloads and loads. As the scientific community focuses on improving the existing satellites technologies in order to make them suitable for future and longer missions, the most promising technique is to model the electrical power system so it has a better reliability, efficiency and stability. As the power distribution units on a spacecraft bus act as Constant Power Loads (CPL), being aware of the stability issues associated with such loads is the focus of this thesis. Despite the fact that small signal stability can provide useful information about the system, still the full large signal analysis is required to guarantee robust stability. This research will present a full model of the EPS of MYSAT-1, the first earth observation CubeSat built at Khalifa University-YAHSAT lab, including the primary power source, energy storage, energy management and loads using MATLAB/Simulink platform. Furthermore, the dynamic stability of the EPS supplying constant power loads is studied. In addition, the full stability analysis is examined in this research in addition to the stability region determination. The parameters that are sensitive to the stability are studied along with the effect of changing the CPL values on the region of attraction, this will ultimately help engineers and researchers in determining the system's design criteria and the safe operating area in terms of excellent transient responses and strong robustness.
Date of AwardMay 2021
Original languageAmerican English


  • CubeSats
  • EPS
  • CPL
  • Stability
  • Region of Attraction.

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