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Title: Design and Implementation of a Bipolar-Unipolar Switched Boundary Current Mode (BCM) Control GaN-Based Single-Phase Inverter
This paper presents the design and implementation of a boundary current mode (BCM) modulated GaN-based single phase inverter using a combination of bipolar and unipolar switching. Both unipolar and bipolar BCM-switched full bridge inverters are explored in detail in the context of efficiency, output current distortion and leakage current. Although the unipolar switched BCM inverter results in a higher efficiency in comparison to the bipolar switched inverter, it leads to a higher output current distortion at the low frequency zero crossing. On the other hand, the bipolar switched BCM inverter yields a low leakage current and reduced output current distortion, but exhibits lower efficiency. To overcome the low frequency zero crossing current distortion while maintaining a high efficiency, a combination of bipolar and unipolar switching in a BCM inverter is proposed. An experimental prototype has been built to validate the proposed control technique and modulation scheme. The proposed approach achieves a 2% efficiency improvement in comparison to the standard bipolar switched BCM inverter and a THD of 1.15%.  more » « less
Award ID(s):
Author(s) / Creator(s):
Date Published:
Journal Name:
IEEE Energy Conversion Congress and Exposition (ECCE)
Page Range / eLocation ID:
6473 to 6480
Medium: X
Sponsoring Org:
National Science Foundation
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