Liwei Wang, Author at School of Engineering

Liwei Wang

Associate Professor

Electrical

Office: EME4213
Phone: 250.807.8137
Email: liwei.wang@ubc.ca

Graduate student supervisor

Research Summary

Electric Power Systems; High Power Electronics; HVDC and FACTS Systems; Electrical Machines and Drives; Real-time Simulation

Courses & Teaching

Power Systems; Power Electronics; Electromechanical Devices; Circuit Analysis; Numerical Modeling and Analysis

Biography

Dr. Wang received his Ph.D. degree in Electrical and Computer Engineering from The University of British Columbia, Vancouver, BC, Canada, in January 2010. Before he completed his Ph.D., he was an Internship Researcher at ABB Switzerland Corporate Research Center, Baden-Dattwil, Switzerland. He was a Postdoctoral Research Fellow in the Department of Electrical and Computer Engineering, University of British Columbia from February 2010 to July 2010. In August 2010, he joined ABB Sweden Corporate Research Center, Västerås, Sweden, as a Scientist and then a Senior Scientist. From July 2014, he joined School of Engineering, the University of British Columbia, Kelowna, BC, Canada as an Assistant Professor and then an Associate Professor. He presently serves as an Associate Editor for IEEE Journal of Emerging and Selected Topics in Industrial Electronics (JESTIE). He was an Associate Editor for IEEE Transactions on Energy Conversion (TEC) and IEEE Power Engineering Letters from 2014-2022. He was also the Chair of IEEE Task Force on Interfacing Techniques for Simulation Tools from 2019 to 2022. Dr. Wang established his research lab “Flexible Power Transmission Laboratory for Renewable Energy Integration” in UBC Okanagan Campus. The laboratory received $305,000 CAD funding from Canadian Foundation for Innovation (CFI) and BC Knowledge Development Fund (BCKDF) in 2017 and NSERC RTI grant of $150,000 CAD in 2021 to acquire the-state-of-the-art lab equipment. The lab equipment and infrastructure include real-time power system/electronics simulators from OPAL-RT, modular multilevel converter test-bench, induction machine drives, measurement and data acquisition systems (TEK oscilloscopes, high voltage, high current probes). He received two Teaching Excellence Awards in 2018 and 2021 from the School of Engineering, UBCO. His Ph.D. students received two Best Paper Awards from the 10^th IEEE Annual Information Technology, Electronics, and Mobile Communication Conference, (IEEE IEMCON 2019) and the 47^th IEEE Photovoltaic Specialists Conference (IEEE PVSC47 2020) and one Best Paper Award Finalist from the 2022 IEEE Electrical Power and Energy Conference (EPEC 2022). His Master and Ph.D. students have received several prestigious scholarships such as NSERC Postdoctoral Fellowships, NSERC Alexander Graham Bell Canada Graduate Scholarship, NSERC Canada Graduate Scholarship – Masters, NSERC Undergraduate Student Research Awards.

Degrees

PhD – Electrical Engineering (The University of British Columbia)
MSc – Electrical Engineering (Tianjin University, China)
BSc – Electrical Engineering (Hebei University of Technology, China)

Research Interests & Projects

Dr. Wang’s research interests include power system analysis, operation and simulation, electrical machine and drives, power electronic converter design, control and topology, power semiconductors modeling and characterization, utility power electronics applications, HVDC and FACTS, renewable energy sources, and distributed generation.

Selected Publications & Presentations

Levi Bieber, Liwei Wang, and Juri Jatskevich, “Numerically Efficient and Accurate Analytical Converter Semiconductor Loss Calculation for Hybrid and Modular Multilevel Converters in VSC-HVDC Applications,” Accepted to IEEE Open Access Journal of Power and Energy, OAJPE-00048-2024.
Saeed Sharifi, Levi Bieber, Liwei Wang, and Juri Jatskevich, “Flying-Stack Modular Multilevel Converter with Fault Blocking Capability for HVDC Applications,” Accepted to IEEE Journal of Emerging and Selected Topics in Power Electronics, JESTPE-2024-02-0260.
Sheraz Baig, Milad Saeed Ebrahimi, Juri Jatskevich, Liwei Wang, and Aria Fani, “Wide-Band Constant-Parameter Voltage-Behind-Reactance Model of Squirrel-Cage Induction Machines,” Accepted to IEEE Transactions on Energy Conversion, TEC-01052-2023.
Fei Zhang, Wei Gu, Yuanshi Zhang, Liwei Wang, and Wei Li, “General Linearized Model of Voltage Source Converter with Fixed Nodal Admittance Matrix,” Accepted to IEEE Transactions on Power Electronics, TPEL-SSLettG-2024-03-0065.
Yuanshi Zhang, Wenyan Qian, Fei Zhang, Liwei Wang, Qinran Hu, and Wei Li, “Adaptive Voltage Reference Based Controls of Converter Power Sharing and Pilot Voltage in HVDC System for Large-Scale Offshore Wind,” Accepted to IEEE Open Access Journal of Power and Energy, OAJPE-00104-2023.
Levi Bieber, Liwei Wang, and Juri Jatskevich, “Multiplexed-Stack Converter with DC-Fault Ride-Through Capability and High Compactness”, Accepted to IEEE Journal of Emerging and Selected Topics in Power Electronics, JESTPE-2023-05-0663.
Levi Bieber, Liwei Wang, and Juri Jatskevich, “Dual-Arm Modular Multilevel Converter With a Compact Footprint for VSC-HVDC Applications”, Accepted to IEEE Transactions on Power Delivery, TPWRD-01539-2022.
Levi Bieber, Liwei Wang, Juri Jatskevich, and Wei Li, “A Universal Equivalent Model for Real-Time CPU/FPGA Co-Simulation of Hybrid Cascaded Multilevel Converters”, Accepted to IEEE Access, Access-2022-27935, 2022.
Fei Zhang, Levi Bieber, Yuanshi Zhang, Wei Li, and Liwei Wang, “A Multi-port DC Power Flow Controller Integrated with Modular Multilevel Converter for Meshed Multi-terminal HVDC Grids,” Accepted to IEEE Transactions on Sustainable Energy, TSTE-00634-2022.
Yuanshi Zhang, Liwei Wang, and Chris Struthers, “A Novel Two-Phase Load Compensation Method Under Unbalanced Voltages for Renewable Energy Integration”, Accepted to Frontiers in Energy Research, 2022.
Levi Bieber, Joel Pfannschmidt, Liwei Wang, Juri Jatskevich, and Wei Li, “A Hybrid Five-Level Modular Multilevel Converter with High Efficiency and Small Energy Storage Requirements for HVDC Transmission”, Accepted to IEEE Transactions on Industrial Electronics, 21-TIE-2306.
Severin Nowak, Christine Chen, and Liwei Wang, “Distributed Measurement-based Optimal DER Dispatch with Estimated Sensitivity Models”, Accepted to IEEE Transactions on Smart Grid, TSG-00254-2021.
Jintao Han, Levi Bieber, Jared Paull, Liwei Wang, Wei Li, and Jean-Nicolas Paquin, “Real-Time Simulation of Hybrid Three-Level and Modular Multilevel Converter Based on Complete Equivalent Circuit Model”, Accepted to IEEE Open Access Journal of Power and Energy, OAJPE-00070-2021.
Yuanshi Zhang, Amin Shotorbani, Liwei Wang, and Wei Li, “A Combined Hierarchical and Autonomous DC Grid Control for Proportional Power Sharing with Minimized Voltage Variation and Transmission Loss,” Accepted to IEEE Transactions on Power Delivery, TPWRD-01577-2020.
Yuanshi Zhang, Xuekun Meng, Abrar Malik, and Liwei Wang, “The Use of Analytical Converter Loss Formula to Eliminate DC Slack/Droop Bus Iteration in Sequential AC-DC Power Flow Algorithm,” Accepted to International Journal of Electrical Power and Energy Systems, IJEPES-D-20-00682.
Yuanshi Zhang, Amin Shotorbani, Liwei Wang, and Behnam Mohammadi-Ivatloo,”Distributed Secondary Control of a Microgrid with A Generalized PI Finite-time Controller,” Accepted to IEEE Open Access Journal of Power and Energy, OAJPE-00097-2020, 2020.
Yuanshi Zhang, Liwei Wang, and Wei Li, “Autonomous DC Line Power Flow Regulation Using Adaptive Droop Control in HVDC Grid,” Accepted to IEEE Transactions on Power Delivery, TPWRD-00817-2020, 2020.
Yuanshi Zhang, Amin Shotorbani, Liwei Wang, and Behnam Mohammadi-Ivatloo,”Enhanced PI Control and Adaptive Gain Tuning Schemes for Distributed Secondary Control of an Islanded Microgrid,” Accepted to IET Renewable Power Generation, RPG-2020-0894, 2020.
Peyman Amiri, Chris Botting, Marian Craciun, Wilson Eberle, and Liwei Wang, “Analytic-Adaptive LLC Resonant Converter Synchronous Rectifier Control”, Accepted to IEEE Transactions on Power Electronics, TPEL-Reg-2020-05-1011, 2020.
Yuanshi Zhang, Xuekun Meng, Amin Shotorbani, and Liwei Wang, “Minimization of AC-DC Grid Transmission Loss and DC Voltage Deviation Using Adaptive Droop Control and Improved AC-DC Power Flow Algorithm”, Accepted to IEEE Transactions on Power Systems, TPWRS-00116-2020.
Haitao Li, Cunshan Zhang, Liwei Wang, Zhenmei Li, Yunzhu An, Xiaohui Liu, and Xiaoyu Liang, “A Repetitive High-Current Pulse Generator Circuit Based on Multi-stage Pulse Transformers,” Accepted to IEEE Journal of Emerging and Selected Topics in Power Electronics, JESTPE-2020-03-0239, 2020.
Zhao Bo, Haitao Li, Liwei Wang, Jian Liu, and Xiaohui Liu, “A New Modular XRAM-like Inductive High-current Pulse Generator Circuit Topology,” Accepted to IEEE Access, Access-2020-51700, 2020.
Yuri R. Rodrigues, Abdelaziz, Morad, and Liwei Wang, “Resilience-Oriented D-PMU based Frequency Controller for Islanded Microgrids with Flexible Resources Support,” Accepted to IEEE Transactions on Power Delivery, TPWRD-01174-2020.
Yuri R. Rodrigues, Abdelaziz, Morad, and Liwei Wang, “D-PMU Based Distributed Voltage and Frequency Control for DERs in Islanded Microgrids,” Accepted to IEEE Transactions on Sustainable Energy, TSTE-00192-2020.
Jintao Han, Levi Bieber, Yuanshi Zhang, Liwei Wang, Wei Li and Jean Belanger, “Detailed Equivalent and Average Value Models of Hybrid Cascaded Multilevel Converters for Efficient and Accurate EMT‐Type Simulation”, Accepted to IEEE Transactions on Power Delivery, TPWRD-00089-2020, 12 pages, 2020.
Severin Nowak, Christine Chen, and Liwei Wang, “Measurement-based Optimal DER Dispatch with a Recursively Estimated Sensitivity Model”, Accepted to IEEE Transactions on Power Systems, TPWRS-01899-2019, 11 pages, 2020.
Ashraf Khan, Usman Ali Khan, Liwei Wang, Wilson Eberle, and Mohammed Agamy, “AC-AC Converter Based Multilevel Inverters for Photovoltaic Applications”, Accepted to IEEE Journal of Emerging and Selected Topics in Power Electronics, JESTPE-2019-12-1290, 2020.
Yuanshi Zhang, Amin Shotorbani, Liwei Wang, and Wei Li, “Distributed Voltage Regulation and Automatic Power Sharing in Multi-Terminal HVDC Grids”, IEEE Transactions on Power Systems, vol. 35, no. 5, 2020.
Xuekun Meng, Jintao Han, Liwei Wang, and Wei Li, “A Unified Arm Module Based Average Value Model for Modular Multilevel Converter”, IEEE Access, vol. 8, 2020.
Levi Bieber, Liwei Wang, and Wei Li, “A Low-Loss Thyristor-Based Hybrid Three-Level and Modular Multilevel Converter with DC Fault Blocking Capability for HVDC Transmission”, IEEE Open Access Journal of Power and Energy, vol. 7, 2020.
Severin Nowak, Liwei Wang, and Malcolm Metcalfe, “Two-Level Centralized and Local Voltage Control in Distribution Systems Mitigating Effects of Highly Intermittent Renewable Generation”, International Journal of Electrical Power and Energy Systems, vol. 119, 2020.
Ashraf Khan, Yun W. Lu, Usman Ali Khan, Liwei Wang, Wilson Eberle, and Mohammed Agamy, “Novel Transformerless Buck-Boost Inverters without Leakage Current “, IEEE Transactions on Industrial Electronics, vol. 67, no. 12, 2020.
Ashraf Ali Khan, Yun W. Lu, Fazal Akber, Usman Ali Khan, Liwei Wang, Wilson Eberle, and Mohammed Agamy, “Coupled-Inductor Buck-Boost Inverters with Reduced Current Ripple,” IEEE Transactions on Power Electronics, vol. 35, no. 8, 2020.
Levi Bieber, Joel Pfannschmidt, Liwei Wang, Alireza Nami, and Wei Li, “A Hybrid Three-Level and Modular Multilevel Converter with DC Fault Blocking Capability and Reduced Semiconductor Losses”, IEEE Transactions on Power Delivery, vol. 35, no. 4, 2020.
Xuekun Meng, Jintao Han, Joel Pfannschmidt, Liwei Wang, Wei Li, Fei Zhang, and Jean Belanger, “Combining Detailed Equivalent Model with Switching-Function-Based Average Value Model for Fast and Accurate Simulation of MMCs”, IEEE Transactions on Energy Conversion, vol. 35, no. 1, 2020.
Xuekun Meng, Jintao Han, Levi Bieber, Liwei Wang, Wei Li, and Jean Belanger, “A Universal Blocking-module-based Average Value Model of Modular Multilevel Converters with Different Types of Submodules”, IEEE Transactions on Energy Conversion, vol. 35, no. 1, 2020.
Yuri R. Rodrigues, Morad Abdelaziz, and Liwei Wang, “D-PMU Based Secondary Frequency Control for Islanded Microgrids,” IEEE Transactions on Smart Grid, vol. 11, no. 1, 2020.
Ashraf Ali Khan, Yun Lu, Wilson Eberle, Liwei Wang, Khan Usman, and Honnyong Cha, “Single-Phase Split-Inductor Differential Boost Inverters”, IEEE Transactions on Power Electronics, vol. 35, no, 1, 2020.
Ashraf Ali Khan, Wayne Lu, Wilson Eberle, Liwei Wang, Usman Ali Khan, Muhammad Agamy, and Honnyong Cha, “Single-Stage Bidirectional Buck-Boost Inverters Using a Single-Inductor and Eliminating Common Mode Leakage Current,” IEEE Transactions on Power Electronics, vol. 35, no. 2, 2020.
Mohammad Toulabi, Liwei Wang, Levi Bieber, Shaahin Filizadeh, and Juri Jatskevich, “A Universal High-Frequency Induction Machine Model and Characterization Method for Arbitrary Stator Winding Connections”, IEEE Transactions on Energy Conversion, vol. 34, no. 3, 2019.
Janesh Rupasinghe, Shaahin Filizadeh, and Liwei Wang, “A Dynamic Phasor Model of an MMC with Extended Frequency Range for EMT Simulations”, IEEE Journal of Emerging and Selected Topics in Power Electronics, vol. 7, no. 1, 2019.
Amin Mohammadpour Shotorbani, Behnam Mohammadi-Ivatlooa, Liwei Wang, M. Marzband, and Mehran Sabahi, “Application of finite-time control Lyapunov function in low-power PMSG wind energy conversion systems for sensorless MPPT”, International Journal of Electrical Power and Energy Systems, vol. 106, 2019.
Seyyedmilad Ebrahimi, Navid Amiri, Liwei Wang, and Juri Jatskevich “Parametric Average-Value Modeling of Thyristor-Controlled Rectifiers with Internal Faults and Asymmetrical Operation”, IEEE Transactions on Power Delivery, vol. 34, no. 2, 2019.
Amin Shotorbani, Behnam Mohammadi-Ivatloo, Liwei Wang, Saeid Ghassem-Zadeh, Seyed Hossein Hosseini, “Distributed secondary control of battery energy storage systems in a stand-alone microgrid”, IET Journal of Generation, Transmission & Distribution, vol. 12, no. 17, 2018.
Seyyedmilad Ebrahimi, Navid Amiri, Yingwei Huang, Liwei Wang, and Juri Jatskevich “Average-Value Modeling of Diode Rectifier Systems under Asymmetrical Operation and Internal Faults”, Accepted to IEEE Transactions on Energy Conversion, vol. 33, no. 4, Dec. 2018.
Seyyedmilad Ebrahimi, Navid Amiri, Saeed Rezaee, Liwei Wang, and Juri Jatskevich, “Efficient Modelling of Six˗Phase PM Synchronous Machine-Rectifier Systems in State-Space Simulation Packages,” In press, IEEE Transactions on Energy Conversion, vol. 33, no. 3, Sep. 2018.
Amin Shotorbani, Xuekun Meng, Liwei Wang, and Behnam Mohammadi-Ivatloo, “A Decentralized Multi-loop Scheme for Robust Control of a Power Flow Controller with Two Shunt Modular Multilevel Converters”, IEEE Transactions on Industrial Informatics, vol. 14, no. 10, Oct. 2018.
Seyyedmilad Ebrahimi, Navid Amiri, Hamid Atighechi, Yingwei Huang, Liwei Wang, and Juri Jatskevich, “Generalized Parametric Average-Value Model of Line-Commutated Rectifiers Considering AC Harmonics with Variable Frequency Operation” accepted to IEEE Transactions on Energy Conversion, vol. 33, no. 1, Mar. 2018.
Hamid Atighechi, Po Hu, Seyyedmilad Ebrahimi, Jun Lu, Guihua Wang, and Liwei Wang, “An Effective Load Shedding Remedial Action Scheme Considering Wind Farms Generation”, International Journal of Electrical Power and Energy Systems, vol. 95, Feb. 2018.
Xuekun Meng and Liwei Wang, “Hybrid Electromagnetic and Electromechanical Transient Simulation of AC Grids Integrated with Modular-Multilevel-Converter-Based DC Transmission,” IET Journal of Generation, Transmission, and Distribution, vol. 11, no. 12, Mar. 2017.
Chengshan Wang, Xiaopeng Fu, Peng Li, Jianzhong Wu, and Liwei Wang, “Multiscale Simulation of Power System Transients Based on the Matrix Exponential Function“, IEEE Transactions on Power Systems, vol. 32, no. 3, May. 2017.
Seyyedmilad Ebrahimi, Navid Amiri, Hamid Atighechi, Liwei Wang, Juri Jatskevich, “Verification of Parametric Average-Value Model for Thyristor-Controlled Rectifier Systems for Variable-Frequency Wind Generation Systems,” IEEE Power Engineering Letters, vol. 31, no. 1, 2016.
Francis Therrien, Liwei Wang, Mehrdad Chapariha, and Juri Jatskevich, “Constant-Parameter Interfacing of Saturable Induction Machine Models in EMTP-Type Programs,” IEEE Transactions on Energy Conversion, vol.31, no.1, 2016.
Muhammad Nawaz, Nan Chen, Filippo Chimento, and Liwei Wang, “Static and Dynamic Characterization of High Power Silicon Carbide BJT Modules,” IEEE Industrial Applications Magazine, vol. 52, no. 6, 2016.
Filippo Chimento, Nan Chen, Muhammad Nawaz, and Liwei Wang, “Dynamic Characterization of Parallel-Connected High-Power IGBT Modules,” IEEE Transactions on Industrial Applications, vol. 51, no. 1, 2015.
Francis Therrien, Liwei Wang, Juri Jatskevich and Oleg Wasynczuk, “Efficient Explicit Representation of AC Machines Main Flux Saturation in State-Variable-Based Transient Simulation Packages,” IEEE Transactions on Energy Conversion, vol. 28, no. 2, 2013.
Liwei Wang and Juri Jatskevich, “A Phase-Domain Synchronous Machine Model with Constant Equivalent Conductance Matrix for EMTP-Type Solution,” IEEE Transactions on Energy Conversion, invited paper, vol. 28, no. 1, 2013.
Mehrdad Chapariha, Liwei Wang and Juri Jatskevich, Hermann Dommel, and Steven D. Pekarek, “Constant Parameter RL-branch Equivalent Circuit for Interfacing AC Machine Models in State-Variable-Based Simulation Packages,” IEEE Transactions on Energy Conversion, vol. 27, no. 3, 2012.
Liwei Wang and Juri Jatskevich, “Magnetically-Saturable Voltage-Behind-Reactance Synchronous Machine Model for EMTP-Type Solution,” IEEE Transactions on Power Systems, vol. 26, no. 4, 2011.
Liwei Wang, Carl N.M. Ho, Francisco Canales, and Juri Jatskevich, “High-Frequency Modeling of the Long-Cable-Fed Induction Motor Drive System Using TLM Approach for Predicting Overvoltage Transients,” IEEE Transactions on Power Electronics, vol. 25, no. 10, 2010.
Liwei Wang, Juri Jatskevich, Venkata Dinavahi, Hermann Dommel, Juan Martinez, Kai Strunz, Michel Rioual, Gary Chang, and Reza Iravani, “Methods of Interfacing Rotating Machine Models in Transient Simulation Programs,” IEEE Transactions on Power Delivery, vol. 25, no. 2, 2010.
Liwei Wang and Juri Jatskevich, “Approximate Voltage-Behind-Reactance Induction Machine Model for Efficient Interface with EMTP Network Solution,” IEEE Transactions on Power Systems, vol. 25, no. 2, 2010.
Liwei Wang and Juri Jatskevich, “Including Magnetic Saturation in Voltage-Behind-Reactance Induction Machine Model for EMTP-Type Solution,” IEEE Transactions on Power Systems, vol. 25, no. 2, 2010.
Liwei Wang, Juri Jatskevich, Chengshan Wang and Peng Li, “A Voltage-Behind-Reactance Induction Machine Model for the EMTP-Type Solution,” IEEE Transactions on Power Systems, vol. 23, no. 3, Aug. 2008.
Liwei Wang, Juri Jatskevich, and Steven Pekarek, “Modeling of Induction Machines Using a Voltage-Behind-Reactance Formulation,” IEEE Transactions on Energy Conversion, vol. 23, no.2, Jun. 2008.
Liwei Wang, Juri Jatskevich, and Hermann Dommel, “Re-examination of Synchronous Machine Modeling Techniques for Electromagnetic Transient Simulations,” IEEE Transactions on Power Systems, vol. 22, no. 3, Aug. 2007.
Liwei Wang and Juri Jatskevich, “A Voltage-Behind-Reactance Synchronous Machine Model for the EMTP-Type Solution,” IEEE Transactions on Power Systems, vol. 21, no. 4, Nov. 2006.

Patents Pending

Alireza Nami, Frans Dijkhuizen, Jiaqi Liang, Liwei Wang, and Tomas Jonsson, PCT/EP2014/065673, “A multilevel converter with reduced AC fault handling rating,” ABB Sweden, filed in July 2014.
Alireza Nami, Frans Dijkhuizen, Liwei Wang, WO2014154265A1, “Hybrid power converter with modular multilevel strings in neutral point clamping topologies,” ABB Sweden, filed in March 2013.
Alireza Nami, Liwei Wang, Frans Dijkhuizen, WO2014154241A1, “A multilevel converter with cell type mixing,” ABB Sweden, filed in March 2013.
Alireza Nami, Liwei Wang, WO2014111164, “A multilevel converter with hybrid full-bridge cells”, ABB Sweden, filed in January 2013.
Alireza Nami, Frans Dijkhuizen, Jiaqi Liang, Liwei Wang, and Tomas Jonsson, WO2014111595A1, “A multilevel converter with hybrid full-bridge cells”, ABB Sweden, filed in January 2013.
Alireza Nami, Liwei Wang, WO2014124761A2, PCT/EP2014/050228A1, “Converter cell, high-voltage multilevel converter and associated method,” ABB Sweden, filed in February 2013.
Alireza, Nami, Liwei Wang, EP2768133A1 “Converter cell with reduced power losses, high voltage multilevel converter and associated method,” ABB Sweden, filed in February 2013.
Liwei Wang, Alireza Nami, SE1300439A1, “A submodule for modular multilevel converter”, ABB Sweden, filed in June 2013.
Liwei Wang, Filippo Chimento, Muhammad Nawaz, and Jing Ni, SE1200544A1, “Method and apparatus for cooling semiconductor modules in HVDC converters”, ABB Sweden, filed in September 2012.
Liwei Wang, Filippo Chimento, Muhammad Nawaz, and Willy Hermansson, SE1200545A1, “Methods for paralleling semiconductor modules in an HVDC application”, ABB Sweden, filed in September, 2012.
Ola Jeppsson, Ake Oberg, Liwei Wang, Filippo Chimento, WO2013185815A1, PCT/EP2012/061208, “Bypass switch assembly”, ABB Sweden, filed in June 2012.(Granted in US in 2015)
Alireza Nami, Liwei Wang and Staffan Norgga, WO2013135300, PCT/EP2012/054625, “Arrangement for conversion between ac and dc”, ABB Sweden, filed in March 2012.
Liwei Wang, Jianping Wang, Pedro Rodriguez, Mustafa Ibrahim, Antonis Marinopoulos, Zoran Gajic, WO2013004285, PCT/EP2011/061188,”System for detecting internal winding faults of a synchronous generator, computer program product and method”, ABB Sweden, filed in July 2011 (Granted in US in 2014)