TY - JOUR
T1 - A High-Frequency Isolated Multilevel Cascaded-Type Bipolar Direct PWM AC-AC Converter for Utility Voltage Compensation
AU - Ahmed, Hafiz Furqan
AU - Moursi, Mohamed Shawky El
AU - Zahawi, Bashar
AU - Hosani, Khalifa Al
N1 - Funding Information:
Manuscript received March 10, 2020; revised July 13, 2020; accepted August 19, 2020. Date of publication September 2, 2020; date of current version May 19, 2021. Paper 2020-MCRE-0301.R1, approved for publication in the IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS by the Energy Systems Committee of the IEEE Industry Applications Society. This work was supported by the Khalifa University of Science and Technology under Award CIRA-2018-37. (Corresponding author: Hafiz Furqan Ahmed.) The authors are with the Advanced Power and Energy Center (APEC), Department of Electrical Engineering and Computer Science, Khalifa University, Abu Dhabi 127788, United Arab Emirates. Mohamed Shawky El Moursi is currently on leave from the Faculty of Engineering, Mansoura University, Mansoura 35516, Egypt (e-mail: [email protected]; [email protected]; [email protected]; [email protected]).
Publisher Copyright:
© 1972-2012 IEEE.
PY - 2021/5/1
Y1 - 2021/5/1
N2 - A high-frequency isolated multilevel cascaded-type bipolar direct PWM ac-ac converter is proposed. By cascading N-unit cells, the converter can produce symmetric bipolar voltage gain of ±ND. It does not require a separate ac source for each unit cell, and can provide higher ac output voltages with multiple levels using low-voltage rating devices, decreasing output voltage harmonics and filtering requirements. Moreover, phase-shift PWM switching is employed, increasing the effective frequency of the output filter, further reducing its requirements. The converter can be utilized as a dynamic voltage restorer (DVR) for grid voltage regulation, with the following features: No need for an external dc source, separate ac sources, and a line-frequency voltage injection transformer. Injection of higher voltage magnitudes than the line voltage, mitigating deep voltage sags. Injection of a negative series voltage to provide compensation for voltage swells. The detailed circuit operation is explained together with component design guidelines and application as DVR. Finally, experimental results are provided using an 800-W scale-down laboratory prototype.
AB - A high-frequency isolated multilevel cascaded-type bipolar direct PWM ac-ac converter is proposed. By cascading N-unit cells, the converter can produce symmetric bipolar voltage gain of ±ND. It does not require a separate ac source for each unit cell, and can provide higher ac output voltages with multiple levels using low-voltage rating devices, decreasing output voltage harmonics and filtering requirements. Moreover, phase-shift PWM switching is employed, increasing the effective frequency of the output filter, further reducing its requirements. The converter can be utilized as a dynamic voltage restorer (DVR) for grid voltage regulation, with the following features: No need for an external dc source, separate ac sources, and a line-frequency voltage injection transformer. Injection of higher voltage magnitudes than the line voltage, mitigating deep voltage sags. Injection of a negative series voltage to provide compensation for voltage swells. The detailed circuit operation is explained together with component design guidelines and application as DVR. Finally, experimental results are provided using an 800-W scale-down laboratory prototype.
KW - Direct ac-ac converter
KW - dynamic voltage restorer (DVR)
KW - high-frequency isolation
KW - inverting and noninverting operations
KW - multilevel cascaded-type
UR - https://www.scopus.com/pages/publications/85106859892
U2 - 10.1109/TIA.2020.3021371
DO - 10.1109/TIA.2020.3021371
M3 - Article
AN - SCOPUS:85106859892
SN - 0093-9994
VL - 57
SP - 3188
EP - 3201
JO - IEEE Transactions on Industry Applications
JF - IEEE Transactions on Industry Applications
IS - 3
M1 - 9184985
ER -