Stability Analysis of Integrated Power System in Multicycle Dynamic Process

The integrated power system (IPS) with pulse load involves the dynamic processes of millisecond-level switching period and second-level pulse period. The characteristics of this kind of multicycle dynamic process cause much difficulty in analyzing system stability. For this reason, this paper presents a multicycle coupling mathematical model of the IPS with pulse load and proposes an algorithm based on the state variables for analyzing the sensitivity of the preceding switching period which can rapidly and accurately calculate the periodic orbit and stability margin of the system. Considering a little change in the system state variables under small disturbance, this paper uses the pulse-period average model to simplify the calculation. The simulation analysis shows that the pulse-period average model has the same stability margin with the multicycle coupling model. The critical pulse power calculated by the above models is 5.5 and 17 kW when the constant power is 20 and 14 kW respectively, which is consistent with the time domain simulation. It may provide technical support for the stability analysis of the IPS with pulse load. (c) 2021 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.