Stability Analysis of Bidirectional Dual Active Bridge Converter With Input and Output LC Filters Applying Power-Feedback Control

This article analyzes the dynamic characteristics of a dual active bridge (DAB) converter with input/output LC filters connected and power-feedback control applied, and then discusses an impedance stability criterion about both side LC filters and the converter. Power control is suitable as a control method for grid-connected converters because of its affinity with the energy management system, which is being introduced as a new way to operate power systems in recent years. In order to provide stable power supply, it is necessary to ensure the stability of the converter, and information on dynamic characteristics is essential for the design and development of converters. Since there are no previous papers found yet where the impedance stability criterion is applied when LC filters are connected to both ends of a bidirectional DAB converter, this article discusses the procedures and key points to be considered to apply the criterion. Based on the analysis, the design guidelines of the system will be discussed.