DC Arc Fault Detection and Protection in DC Based Electrical Power Systems

134 Pages·2015·8.51 MB·English

DC Arc Fault Detection and Protection in DC Based
Electrical Power Systems
Dissertation
Presented in Partial Fulfillment of the Requirements for the Degree
Doctor of Philosophy in the Graduate School of The Ohio State
University
By
Xiu Yao, B.S., M.S.
Graduate Program in Electrical and Computer Enegineering
The Ohio State University
2015
Dissertation Committee:
Dr. Jin Wang, Advisor
Dr. Longya Xu
Dr. Mahesh S. Illindala
Dr. Daniel L. Schweickart
(cid:13)c Copyright by
Xiu Yao
2015
Abstract
DC based electrical power systems are required in many emerging applications,
such as more electric aircraft, hybrid electric vehicle, photovoltaic power plant, resi-
dential microgrid, etc. A very challenging problem in dc systems is arc faults. They
can be caused by loose connections or degraded insulation, where very small air gaps
are created. The voltage difference across the small gap will initiate a plasma arc-
ing channel with extremely high temperature. If not detected and extinguished in
time, arc faults could endanger adjacent circuits and eventually cause fire hazards.
Although it is very crucial to minimize the impact of dc arc faults through timely
detection and extinguishing, the research topic of dc arc fault detection and system
level protection has not been studied very closely before. It is quite recent that dc
systems are being used extensively for power distribution. Moreover, modern energy
sources and power electronics based loads in aforementioned applications also make
this research topic more challenging.
This work proposes a novel detection scheme to improve the detection accuracy
and to reduce unwanted false tripping. It has been achieved by investigating physical
characteristicsofthedcarcandanalyzingthearccurrentsignals. Thevoltage-current
characteristics of the dc arc as well as the high frequency arc noise is modeled and
analyzed. This model enables an accurate simulation study of the dc arc. A new de-
tectionschemebasedontwoarcsignaturesfrombothtimedomainandtime-frequency
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domain is proposed and verified through experiments. This strategy increases the de-
tection accuracy and reduces the possibility of false trip. Moreover, the impact of dc
arc to a larger system, e.g. a dc microgrid with multiple voltage sources and multiple
resistive loads, is studied. The interactions between dc arc faults and two typical
microgrid control strategies are also analyzed. The final portion of this research is
focused on system level detection and protection. A comprehensive dc arc fault de-
tection and protection scheme which can be integrated with the existing protection
system of a dc microgrid is proposed in order to improve protection efficiency and
minimize additional hardware/software installations.
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This is dedicated to my family:
My husband, Mr. Luis Herrera;
My father, Mr. Enhui Yao;
My mother, Mrs. Yunxia Niu.
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Acknowledgments
My deepest gratitude goes to my PhD advisor, Prof. Jin Wang, who has led
me into the door of power electronics and has been consistently providing me with
academic guidance and funding support throughout my study, without which this
dissertation would not have been possible. His profound knowledge and deep insight
in research has inspired me and helped me to develop creative and critical thinking.
His guidance and encouragement has carried me through many difficult times.
I would like to thank Prof. Longya Xu and Prof. Mahesh S. Illindala for serving
on my qualifying, candidacy, and dissertation committees, and for providing many
valuable advices. Special thanks go to Dr. Daniel L. Schweickart from the Air Force
ResearchLaboratoryforservingonmydissertationcommitteeandforprovidingmany
insightful and inspiring advices to my dissertation and research. I would also like to
thank Prof. Vadim I. Utkin for serving on my candidacy committee. Many thanks
go to Prof. Stephen A. Sebo for his guidance and support throughout my PhD study.
His passion for research and teaching, profound knowledge in high voltage, generosity
to reach out and help other people, have deeply made an impact in my life.
I would also like to thank the previous and current members in our group: Dr. Ke
Zou, Dr. Cong Li, Dr. Feng Guo, Mr. Mark J. Scott, Mr. Xuan Zhang, Mr. He Li,
Mr. Mohammed Alsolami, Mr. Chengcheng Yao, Mr. Lixing Fu, and all other fellow
students I have worked with. Thank you all for the friendship, help, and support.
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I am so grateful for the unconditional love and support from my parents, Enhui
Yao and Yunxia Niu, throughout my life. Thank you for giving me the strength and
courage to pursue my dreams. I would also like to thank my parents in law, Amparo
Duque and Fabio Herrera, for their continued support. Last, but not least, I would
like to thank my husband Luis Herrera, whom I love deeply, for his tremendous and
enduring love. His passion for learning and research has influenced me in many ways.
His faith in me has always given me confidence and positive energy whenever I am
faced with difficulties and challenges. Without his support, it would be impossible
for me to accomplish what I have done.
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Vita
July 2007 ...................................B.S. Electrical Engineering,
Xi’an Jiaotong University
July 2010 ...................................M.S. Electrical Engineering,
Xi’an Jiaotong University
December 2014 .............................M.S. Electrical Engineering,
The Ohio State University
Sept 2010 to present ........................Ph.D. student,
The Ohio State University.
Publications
Research Publications
L.Herrera, C.Li, X.Yao, andJ.Wang, “FPGAbaseddetailedreal-timesimulationof
power converters and electric machines for EV HIL applications”, IEEE Transactions
on Industry Applications, vol. 51, no. 2, pp. 1702-1712, Mar./Apr. 2015.
X. Yao, L. Herrera, and J. Wang, “Impact evaluation of series dc arc faults in dc
microgrids”, in Proceedings of 2015 IEEE Applied Power Electronics Conference and
Exposition(APEC), pp. 2953-2958, Charlotte, NC, Mar. 15-19, 2015.
X. Yao, L. Herrera, and J. Wang, “Modulation and control of MMC based multiter-
minal HVDC”, in Proceedings of 2014 IEEE Energy Conversion Congress and Expo
(ECCE), pp. 499-504, Pittsburgh, PA, Sept. 14-18, 2014.
L.Yang, P.Fu, X.Yao, andJ.Wang, “Amodulebasedself-balancedseriesconnection
for IGBTs”, in Proceedings of 2014 IEEE Energy Conversion Congress and Expo
(ECCE), pp. 1953-1958, Pittsburgh, PA, Sept. 14-18, 2014.
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S. Yang, M. Wu, X. Yao, and J. Jiang, “Load modeling and identification based on
ant colony algorithms for EV charging stations”, accepted for publication in IEEE
Transactions on Power Systems, Aug. 2014.
X. Yao, L. Herrera, S. Ji, K. Zou, and J. Wang, “Characteristic study and time
domain discrete-wavelet-transform based hybrid detection of series dc arc faults”,
IEEE Transactions on Power Electronics, vol. 29, no. 6, pp. 3103-3115, June 2014.
X. Yao, L. Herrera, and J. Wang, “A series dc arc fault detection method and
hardware implementation”, in Proceedings of 2013 IEEE Applied Power Electronics
Conference and Exposition(APEC), pp. 2444-2449, Long beach, CA, Mar. 17-21,
2013.
L. Herrera, C. Li, X. Yao,and J. Wang, “FPGA based real time electro-thermal
modeling of power electronics converters”, in Proceedings of 2013 IEEE Applied
Power Electronics Conference and Exposition(APEC), pp. 1725-1729, Long beach,
CA, Mar. 17-21, 2013.
X. Yao, Y. Huang, F. Guo, and J. Wang, “Advanced concepts for vertical stability
power supply in fusion devices”, IEEE Transactions on Plasma Science, vol. 40, no.
3, pp. 761-768, Mar. 2012.
X. Yao, L. Herrera, Y. Huang, and J. Wang, “The detection of dc arc fault: exper-
imental study and fault recognition”, in Proceedings of 2012 IEEE Applied Power
Electronics Conference and Exposition (APEC), pp. 1720-1727, Orlando, FL, Feb.
5-9, 2012.
X. Yao, S. Ji, L. Herrera, and J. Wang, “Arc fault: characteristic study and fault
recognition”, in Proceedings of IEEE 1st International Conference on Electric Power
Equipment - Switching Technology (ICEPE-ST), pp. 387-390, Xi’an, China, Oct.
23-27, 2011.
X. Yao, Y. Huang, F. Guo, and J. Wang, “Advanced concepts for fusion power
supplies”, in Proceedings of IEEE/NPSS 24th Symposium on Fusion Engineering,
pp. 1-6, Chicago, IL, June 26-30, 2011.
X. Zhao, X. Yao, Z. Guo, J. Li, W. Si, and Y. Li, “Characteristics and develop-
ment mechanisms of partial discharge in SF6 gas under impulse voltages”, IEEE
Transactions on Plasma Science, vol. 39, no. 2, pp. 668-674, Feb. 2011.
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X. Zhao, X. Yao, Z. Guo, Y. Wang, J. Li, and Y. Li, “Partial discharge characteristics
and mechanism in voids at impulse voltages”, Measurement Science and Technology,
vol. 22, no. 3, 2011.
Fields of Study
Major Field: Electrical and Computer Enegineering
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