Chinese Journal of Electrical Engineering ›› 2017, Vol. 3 ›› Issue (1): 42-50.

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Multi-Objective Control of Direct-Driven Wind Power Generation System with Frequency Separation

Feng Xu1,2, Ming Cheng1, Jianzhong Zhang1,*   

  1. 1.School of Electrical Engineering, Southeast University, Nanjing, 210096, China;
    2. School of Electric Power Engineering, Nanjing Institute of Technology, Nanjing, 211167, China
  • Published:2019-11-01
  • Contact: E-mail: jiz@seu.edu.cn.
  • About author:Feng Xu received the B. S. and M. S. degree in electrical engineering from Shandong University of Science and Technology, Qingdao, China, in 1995 and 2003, respectively. He is currently working toward the Ph. D. degree in the School of Electrical Engineering, Southeast University, Nanjing, China. His research interests include wind power generation system. Ming Cheng received the Ph. D. from Hong Kong University. He is a IEEE Fellow and IET Fellow. Since 1987, he has been with Southeast University, where he is currently a Distinguished Professor in the School of Electrical Engineering and the Director of the Research Center for Wind Power Generation. From January to April 2011, he was a Visiting Professor with the Wisconsin Electric Machine and Power Electronics Consortium, University of Wisconsin, Madison. His teaching and research interests include electrical machines, motor drives for electric vehicles, and renewable energy generation. He has authored or coauthored over 300 technical papers and 4 books and is the holder of 90 patents in these areas. He has served as chair and organizing committee member for many international conferences. He is a Distinguished Lecturer of the IEEE Industry Applications Society (IAS) in 2015/2016. Jianzhong Zhang received the Ph. D. from Southeast University. Since 2008, he has been with Southeast University, where he is currently a Research Professor in the school of Electrical Engineering. From 2006 to 2007, He was a Visiting Scholar in the Institute of Energy Technology, Aalborg University, Aalborg, Denmark. He was a Visiting Professor at the Worcester Polytechnic Institute, Worcester, USA, in July 2012. His research interests include electric machines, power electronics, and wind power generation. He is a receipient of the Institution Premium Award of the Institutions of Engineering and Technology, U.K.
  • Supported by:
    Supported by the National Natural Science Foundation of China under Grants 51320105002 and 51577025.

Abstract: Variable-speed wind power generation system usually adopts maximum power point tracking (MPPT) below the rated wind speed or constant power control above the rated wind speed. However, single objective control has large dynamic loads on transmission systems. This paper presents a multi-objective control scheme for wind turbine in low wind speed, which achieves not only high power capture efficiency but also low fatigue load on mechanical parts. Input wind speed is separated into two components: a slowly varying seasonal component and a rapidly varying turbulent component. Correspondingly, the machine-side converter controller is divided into low frequency loop and high frequency loops. The low frequency loop implements MPPT control, the high frequency loop reduces the fluctuations of torque, and both loops together suppress the variations of output power. Simulation was conducted in Matlab/Simulink and FAST code was used to further verify the correctness of the multi-objective control strategy.

Key words: Multi-objective control, frequency separation, linear quadratic, maximum power point tracking, power smoothing