Study and Implementation of Closed Loop Control Based on Double Synchronous Rotating Frame for EMU Auxiliary Inverter with Unbalanced Load

  • Huiqing Du
  • Zhigang Liu
  • Yao Fu
  • Lei Wang
  • Lijun Diao
Conference paper
Part of the Lecture Notes in Electrical Engineering book series (LNEE, volume 288)


As one of the EMU auxiliary inverter’s important performances, the symmetry of three-phase voltage puts forward high requirement in the inverter’s topologies and control strategies. Based on the method of symmetrical component, this paper builds positive-, negative-, and zero-sequence mathematical model of the three-phase inverter system with unbalanced load, and then analyses the generation mechanism of asymmetry output voltage. Afterwards it is proposed a double-loop SVPWM control strategy based on double synchronous rotating frame, and further analysis of the working mechanism and realization mode is raised. Finally, it turns out to be reliable and feasible to apply the control strategy after being tested with virtual DSP simulation model with MATLAB, and on a 3 kVA experimental prototype.


Auxiliary inverter Unbalanced load Method of symmetrical component Double-loop control Double synchronous rotating frame 



This work is supported in part by the China National Science and Technology Support Program under Grant 2013BAG21QB00, the National Natural Science Foundation of China under Grant U1134204 and the Fundamental Research Funds for the Central Universities under Grant 2012JBM099.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  • Huiqing Du
    • 1
  • Zhigang Liu
    • 1
  • Yao Fu
    • 1
  • Lei Wang
    • 1
  • Lijun Diao
    • 1
  1. 1.School of Electrical EngineeringBeijing Jiaotong UniversityBeijingChina

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