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Title: Dual-Loop Frequency Synchronization and Load Regulation using a Discrete Time Model for a 7-Level Switched Capacitor WPT Rectifier
In wireless power transfer (WPT) applications, the multi-level switched capacitor topology achieves significant advantages in terms of efficiency, system loading, THD, and output regulation. The topology requires dual-loop control in order to harness these benefits. First, a small signal discrete time model for the 7-level rectifier WPT system is developed. Then, a control loop is designed that enables the rectifier to regulate DC load voltage by varying its modulation scheme. Next, the WPT carrier frequency is sensed and a phase-locked loop is used in combination with the small signal power stage model to design a closed-loop controller that synchronizes frequency and regulates control phase through adjustments of the switching period. Finally, cross-coupling interactions between the two control loops are modeled, and stable dual-loop operation is shown.  more » « less
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Journal Name:
2020 IEEE 21st Workshop on Control and Modeling for Power Electronics (COMPEL)
Page Range / eLocation ID:
1 to 8
Medium: X
Sponsoring Org:
National Science Foundation
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