Transactions on Machine Intelligence

Transactions on Machine Intelligence

Analysis of the Droop Control Method in DC Microgrids with Regard to the Types of Load

Document Type : Original Article

Authors
M. Mahdavyfakhr
M. Hamzeh
E. Afjei
Department of Electrical Engineering, Shahid Beheshti University, Tehran, Iran
10.47176/TMI.2020.34
Abstract
The droop control method enables decentralized load sharing among voltage source converters (VSCs) in microgrids, eliminating the need for centralized control or communication. However, the accuracy of power sharing under droop control can be significantly affected by various factors, including the configuration of the microgrid and the nature of the connected loads. This study presents a comprehensive evaluation of the power-sharing accuracy of the droop control method, specifically examining its performance with three distinct types of electrical loads: constant impedance (CI), constant current (CC), and constant power (CP). Each load type introduces unique challenges that influence the proportional power distribution among converters. Furthermore, the effect of the microgrid’s topology and line impedance variations on the power-sharing capability of droop control is systematically investigated. The research also explores how different DC microgrid configurations affect the reliability and fairness of power distribution. To validate the theoretical findings, detailed simulations are conducted in the MATLAB/Simulink environment. The simulation results confirm the sensitivity of the droop control approach to load type and network structure, offering insights into optimizing controller parameters for enhanced performance and robust load sharing in practical DC microgrid applications.
Keywords
Constant Current Load
Constant Impedance Load
Constant Power Load
Droop Method
Power Sharing Accuracy
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Transactions on Machine Intelligence
Volume 3, Issue 1
Winter 2020
Pages 34-42

  • Receive Date 29 November 2019
  • Revise Date 04 January 2020
  • Accept Date 11 March 2020