Journal of Power Electronics

The Korean Institute of Power Electronics (전력전자학회)
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An adaptive nonlinear droop control for accurate load current sharing and DC bus voltage compensation in a DC power system

  • Tian, Xinna (School of Electrical Engineering, Shandong University) ;
  • Wang, Yubin (School of Electrical Engineering, Shandong University) ;
  • Wang, Fan (School of Electrical Engineering, Shandong University) ;
  • Guo, Zheng (School of Electrical Engineering, Shandong University)
  • Received : 2021.05.14
  • Accepted : 2021.11.19
  • Published : 2022.02.20
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Abstract

The traditional V-I droop control is commonly used to realize current sharing among distributed generators (DGs). Provided that the influence of line resistance cannot be neglected, there exists a trade-of between voltage deviation and current sharing accuracy when designing the droop coefficient. An adaptive nonlinear droop control in the DC power system with constant power load (CPL) is proposed in this paper to achieve accurate current sharing among source converters and reduce the DC bus voltage deviation. In the proposed method, the output current is shared among neighboring source converters via a low-bandwidth communication (LBC) network to adaptively adjust the dynamic regulation coefficient, which is equivalent to the droop coefficient adjustment. The correctness and effectiveness of the proposed method have been preliminarily verified via the simulation of two source converters and a single CPL based on Matlab/Simulink and further validated by the hardware-in-the-loop (HIL) experiment based on Real-Time Laboratory (RTLab) and DSP F28335 with the LBC network implemented by enhanced controlled area network (eCAN) in DSP F28335.

Keywords

Acknowledgement

This research work was supported by the Shandong Provincial Natural Science Foundation (Grant No. ZR2018MEE037).

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