Sequentially controlled distributed solar-array power system with maximum power tracking

Abstract

Presented herein is the sequentially controlled distributed solar-array power system with maximum power tracking (MPT). The power system controller sequentially activates sufficient solar-array sourced dc-dc converter power-processing channels, of which paralleled-outputs supply power to a common load. A "shared-bus" current-sharing method utilizing distributed MPT control is employed to regulate parallel-connected current-mode converters dedicated to each power channel. Among the activated solar-array power channels, the most recently activated channel provides output bus voltage regulation while the previously activated channels are operated in MPT mode. The remaining inactive power channels consume negligible power resulting in lower component temperatures and improved overall long-term system reliability. Through modeling and simulation of a three-channel MPT power system, the sequentially controlled architecture and control concept are validated.