Robust Hysteresis Control for Full-Bridge LLC Resonant Converters Using an Isolated Measurement Scheme
Conference: PCIM Europe 2022 - International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management
05/10/2022 - 05/12/2022 at Nürnberg, Germany
doi:10.30420/565822190
Proceedings: PCIM Europe 2022
Pages: 6Language: englishTyp: PDF
Authors:
Keuck, Lukas; Schafmeister, Frank; Boecker, Joachim (Power Electronics and Electrical Drives, Paderborn University, Germany)
Abstract:
The LLC resonant converter is the preferred topology for many application areas. Outstanding efficiency and power density can be achieved with such an LLC topology, yet it suffers from its poor dynamic behavior when switching frequency control is used. In this paper, a hysteresis control technique is proposed that generates the gate signals based on an isolated current sensor installed in the resonant tank. Unlike switching frequency control, the proposed hysteresis control is robust against parameter deviations of the resonant tank, which lie within a realistic range of 10%. Simulation and experimental results of a cascaded current-mode control show a settling time of 0.3 ms with no overshoot. Practical issues and how they were managed are described in detail.