Liyan Qu

Liyan Qu

Liyan Qu
Contact Information:
244N SEC
City Campus (Lincoln)
(402) 472-5131
lqu2@unl.edu
Email   

Associate Professor
Academic Degrees
  • Ph.D., Electrical Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, 2007
  • M.S., Electrical Engineering, Zhejiang University, Hangzhou, China, 2002
  • B.S., Electrical Engineering, Zhejiang University, Hangzhou, China, 1999
Areas of Research and Professional Interest
  • Modeling techniques to facilitate the analysis and design of complex, high-performance electric energy systems
  • Numerical analysis and computer aided design for electric machinery and power electronic devices and circuits
  • Electric machines and drives
  • Magnetic devices and materials
  • Power management for electric energy systems, e.g., battery-powered systems
  • Renewable energy systems, e.g., wind, solar
  • Wireless power transmission
  • Energy harvesting
Courses Taught

Selected Publications

Refereer Journal Papers:

1.       J. Wang, F. Cheng, W. Qiao, and L. Qu, “Multiscale filtering reconstruction for wind turbine gearbox fault diagnosis under varying-speed and noisy conditions,” IEEE Trans. Industrial Electronics, vol. 65, no. 5, pp 4268-4278, May 2018.

2.       F. Cheng, L. Qu, and W. Qiao, “Fault prognosis and remaining useful life prediction of wind turbine drivetrain gearboxes using current signal analysis,” IEEE Trans. Sustainable Energy, vol. 9, no. 1, pp 157-167, Jan. 2018.

3.       F. Cheng, Y. Peng, L. Qu, and W. Qiao, “Current-based fault detection and identification for wind turbine drivetrain gearboxes,” IEEE Trans. Industry Applications, vol. 53, no. 2, pp. 878-887, Mar.-Apr. 2017.

4.       H. Wang, L. Qu, W. Qiao, and B. Liu, “Magnetic flux valve: A magnetoelectric materials-based device for conversion and control of electric power,” IEEE Trans. Industrial Electronics, vol. 64, no. 3, pp. 2451-2458, Mar. 2017.

5.       Y. Peng, W. Qiao, L. Qu, and J. Wang, “Sensor fault detection and isolation for a wireless sensor network-based remote wind turbine condition monitoring system,” IEEE Trans. Industry Applications, accepted for publication

6.       X. Jin, F. Cheng, Y. Peng, W. Qiao, and L. Qu, “A comparative study on vibration- and current-based approaches for drivetrain gearbox fault diagnosis,” IEEE Industry Applications Magazine, accepted for publication.

7.       F. Cheng, Y. Peng, L. Qu, and W. Qiao, “Current-based fault detection and identification for wind turbine drivetrain gearboxes,” IEEE Transactions on Industry Applications, accepted for publication. (Available online in the IEEE Xplore)

8.       H. Wang, L. Qu, W. Qiao, and B. Liu, “Magnetic flux valve: A magnetoelectric materials-based device for conversion and control of electric power,” IEEE Transactions on Industrial Electronics, vol. 64, no. 3, pp. 2451-2458, Mar. 2017.

9.       C. Wei, Z. Zhang, W. Qiao, and L. Qu, “An adaptive network-based reinforcement learning method for MPPT control of PMSG wind energy conversion systems,” IEEE Transactions on Power Electronics, vol. 31, no. 11, pp. 7837-7848, Nov. 2016.

10.    Z. Zhang, C. Wei, W. Qiao, and L. Qu, “Adaptive saturation controller-based direct torque control for permanent-magnet synchronous machines,” IEEE Transactions on Power Electronics, vol. 31, no. 10, pp. 7112-7122, Oct. 2016.

11.    X. Bai, W. Qiao, and L. Qu, “Robust AC optimal power flow for power networks with wind power generation,” IEEE Transactions on Power Systems, vol. 31, no. 5, pp. 4163-4164, Sept. 2016.

12.    X. Jin, W. Qiao, Y. Peng, F. Cheng, and L. Qu, “Quantitative evaluation of wind turbine faults under variable operational conditions,” IEEE Transactions on Industry Applications, vol. 52, no. 3, pp. 2061-2069, May/Jun. 2016.

13.    Z. Wang, B. Tian, W. Qiao, and L. Qu, “Real-time aging monitoring for IGBT modules using case temperature,” IEEE Transactions on Industrial Electronics, vol. 68, no. 2, pp. 1168-1178, Feb. 2016.

14.    H. Wang, L. Qu, and W. Qiao, “Adjustable-voltage-ratio magnetoelectric transformer,” IEEE Magnetics Letters, vol. 6, Article# 6000104, Sept. 2015.

15.    C. Ma and L. Qu, “Multiobjective optimization of switched reluctance motors based on design of experiments and particle swarm optimization,” IEEE Transactions on Energy Conversion, vol. 30, no. 3, pp. 1144-1153, Sept. 2015.

16.    C. Wei, Z. Zhang, W. Qiao, and L. Qu, “Reinforcement learning-based intelligent maximum power point tracking control for wind energy conversion systems,” IEEE Transactions on Industrial Electronics, vol. 62, no. 10, pp. 6360-6370, Oct. 2015.

17.    Z. Zhang, Y. Zhao, W. Qiao, and L. Qu, “A discrete-time direct-torque control for direct-drive PMSG-based wind energy conversion systems,” IEEE Transactions on Industry Applications, vol. 51, no. 4, pp. 3504-3514, July-Aug. 2015.

18.    J. Zeng, W. Qiao, and L. Qu, “An isolated three-phase bidirectional DC-DC converter for photovoltaic systems with energy storage,” IEEE Transactions on Industry Applications, vol. 51, no. 4, pp. 3493-3503, July-Aug. 2015.

19.    J. Zeng, W. Qiao, and L. Qu, “LCL-resonant single-switch isolated DC-DC converter,” IET Power Electronics, vol. 8, no. 7, pp. 1209-1216, July 2015.

20.    Z. Zhang, Y. Zhao, W. Qiao, and L. Qu, “A space-vector modulated sensorless direct-torque control for direct-drive PMSG wind turbines,” IEEE Transactions on Industry Applications, vol. 50, no. 4, pp. 2331-2341, Jul./Aug. 2014.

21.    J. Zeng, W. Qiao, L. Qu, and Y. Jiao, “An isolated multiport DC-DC converter for simultaneous power management of multiple different renewable energy sources,” IEEE Journal of Emerging and Selected Topics in Power Electronics, vol. 2, no. 1, pp. 70-78, Mar. 2014.

22.    T. Kim, W. Qiao, and L. Qu, “Power electronics-enabled self-X multicell batteries:  A design toward smart batteries,” IEEE Transactions on Power Electronics, vol. 27, no. 11, pp. 4723-4733, Nov. 2012.

23.    L. Qu and W. Qiao, “Constant power control of DFIG wind turbines with supercapacitor energy storage,” IEEE Transactions on Industry Applications, vol. 47, no. 1, pp 359-367, Jan.-Feb. 2011.

24.    W. Qiao, L. Qu, and R. G. Harley, “Control of IPM synchronous generator for maximum wind power generation considering magnetic saturation,” IEEE Transactions on Industry Applications, vol. 45, no. 3, pp. 1095-1105, May-June 2009.

25.    L. Qu and P. L. Chapman, “Extraction of low-order nonlinear inductor models from a high-order physics-based representation,” IEEE Transactions on Power Electronics, vol. 21, no.3, pp. 813-817, May 2006.

26.    L. Qu, J. Wu, and Y. Chen, “Automatic generation and fast implementation of finite element mesh,” Electric Machines and Control, vol. 6, no.1, pp. 34-38, Mar. 2002.

27.    L. Qu, J. Wu, and Y. Chen, “Object-oriented visualization CAD system for DC motor,” Small & Special Electrical Machines, vol. 28, no. 6, pp. 40-42, 2000.