Development of integral-variable-structure control schemes for parallel-buck and parallel-boost DC-DC converters

In this paper we develop variable-structure control schemes for parallel-boost and parallel-buck converters. The advantages of these schemes are the simplicity in design, good dynamic response, the ability to nullify the bus-voltage error and the error between the load currents or the line currents of the converter modules under steady-state conditions, and the ability to reduce the impact of very high-frequency dynamics due to parasitics on the closed-loop system. We outline methods for determining the region of existence and the stability of a sliding manifold for both the converters. Simulation results show good steady-state and dynamic responses.