Abstract：Stability of the cascade DC/DC converter is a significant issue in distributed power supply (DPS) system design. For a single DC/DC converter, the characteristics of closed-loop output impedance are analyzed by simulations and experiments. The optimal criterion show that output impedance should be designed under the condition of manimum input voltage and no-load. The influence of capacitors on the source converter is simulated and analyzed. Several propositional rules are concluded for DC bus filter design. Furthermore, optimization principles are applied to improve the performance of a cascade DC/DC converter, and a voltage disturbance source is injected to obtain the impedance ratio for stability estimation. Experimental results show that impedance ratio optimization is a necessary stable condition for cascade system.
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2009, Vol. 24 
