Modelling and Design of a Droop-Based Cascaded Controller for LLC Resonant Converter
- Resource Type
- Conference
- Authors
- Yang, Xiaotian; Pohlenz, Stephan; Schwanninger, Raffael; Schleippmann, Nico; Wunder, Bernd; Marz, Martin
- Source
- 2023 IEEE Fifth International Conference on DC Microgrids (ICDCM) DC Microgrids (ICDCM), 2023 IEEE Fifth International Conference on. Single:1-6 Nov, 2023
- Subject
- Components, Circuits, Devices and Systems
Computing and Processing
Engineering Profession
Power, Energy and Industry Applications
Signal Processing and Analysis
Transportation
Microgrids
Resonant converters
Switches
Harmonic analysis
State-space methods
Voltage control
Time-domain analysis
Droop Control
Cascaded Control
LLC Resonant Converter
DC Microgrid
- Language
This paper proposes a digital cascaded control strategy for integrating an LLC resonant converter into a DC Microgrid. The designed control scheme is particularly suitable for battery storage applications in discharging mode. The outer loop of the cascaded controller is a droop controller which provides the reference current according to the DC grid voltage. The inner loop regulates the current according to the reference by pulse frequency modulation (PFM). A seventh-order state-space model based on first harmonic approximation (FHA) and extended describing function (EDF) was built to assist the controller design. The proposed control scheme is validated for both buck and boost operation mode in the PLECS simulation environment.