Autonomous and high stability margin power sharing control method for multiple S3R power systems

摘要

DC distribution power supply, based on photovoltaic (PV) and battery, is the basic architecture of electrical power systems in spacecraft. When multiple spacecrafts work together, one of the important issues is the fulfillment of the power sharing among multiple dc standalone power systems because of partial shadow of PV. In this letter, a simple, modular, highly stability margin and autonomous power sharing method is proposed for multiple PV-Battery power systems. Power sharing method is realized through current mode controlled Bidirectional DC-DC Converters (BDDC) integrated in each power system. Sharing Bus Error Amplifier (SBEA) for sharing bus voltage regulation has been added to replace software and telecommunication unit in traditional power sharing method. Moreover, traditional three domains control in individual Sequential Switching Shunt Regulator (S3R) power system has been changed to four domains control. Finally, a simulation and prototype system based on S3R has been designed and implemented to address the proposed power sharing method, and stability of the whole power system has been analyzed. Both simulation and experimental results verify the validity and high stability margin performance of the proposed system.