Principle of multi-time scale order reduction and its application in AC/DC hybrid power systems

Based on singular perturbation theory and matrix eigenvalue perturbation theorem, an order reduction principle of neglecting fast dynamics and fixing slow dynamics is proposed for multi-time scale singular perturbation systems. The proposed principle can ensure steady state stability consistency between original and reduced system. To validate this principle, the switch cycle average singular perturbation models of typical converters are made, and a simple AC/DC hybrid power system is built. Finally, order of the test hybrid power system is reduced by the proposed reduction principle, and simulation results demonstrate the proposed reduction principle is effective and applicable for steady state stability analysis of AC/DC hybrid power systems.