A method and system for double frequency precise suppression of power electronic transformers
By identifying hardware difference parameters and DC operating point compensation online, combined with three-phase vector cancellation technology, the problem of second harmonic voltage fluctuation in three-phase cascaded power electronic transformers was solved, achieving accurate power transfer and improved stability, while reducing capacitor size and cost.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- XI AN JIAOTONG UNIV
- Filing Date
- 2026-04-15
- Publication Date
- 2026-07-17
AI Technical Summary
In existing three-phase cascaded power electronic transformers, the second harmonic voltage fluctuation problem leads to a shortened capacitor life and impaired switching transistor safety. Furthermore, existing suppression strategies are difficult to accurately transfer power, easily introducing additional harmonics or requiring modifications to the control architecture.
By identifying the hardware differences in the cascaded H-bridge power electronic transformers online, calculating and injecting precise double-frequency shift phase angle commands, and combining this with DC operating point offset compensation, the DAB module achieves precise power transfer and eliminates double-frequency power on the low-voltage side using three-phase vector cancellation technology.
It achieves precise transmission of double-frequency power, reduces the size of the high-voltage side capacitor, improves system stability and power quality, reduces hardware cost and size, and is compatible with existing control architectures without modification.
Smart Images
Figure CN122419151A_ABST