Power sharing and management in a utility connected DC microgrid

This paper introduces a control technique for proportional load sharing in a DC microgrid during both islanded and utility connected modes. The DC microgrid is connected to a utility system through an interlinking voltage source converter and a unidirectional DC-DC converter. The DC-DC converter draws the desired amount of power from the utility, while the interlinking converter holds the DC bus voltage. The DERs in the DC microgrid are operated under droop sharing using DC-DC converters. Each DC-DC converter is equipped with a state feedback with integral controller that can regulate its output voltage for a wide range of input voltage fluctuation and load variation. Simulation studies are conducted on PSCAD/EMTDC to validate the proposal.

[1]  B Renders,et al.  A Control Strategy for Islanded Microgrids With DC-Link Voltage Control , 2011, IEEE Transactions on Power Delivery.

[2]  Magdy Saoudi,et al.  Design and implementation of closed-loop control system for buck converter using different techniques , 2017, IEEE Aerospace and Electronic Systems Magazine.

[3]  Mahesh K. Mishra,et al.  Control of photovoltaic-based low-voltage dc microgrid system for power sharing with modified droop algorithm , 2016 .

[4]  Arindam Ghosh,et al.  Power Management and Power Flow Control With Back-to-Back Converters in a Utility Connected Microgrid , 2010, IEEE Transactions on Power Systems.

[5]  Debapriya Das,et al.  An Enhanced Droop Control Method for Accurate Load Sharing and Voltage Improvement of Isolated and Interconnected DC Microgrids , 2016, IEEE Transactions on Sustainable Energy.

[6]  Arindam Ghosh,et al.  DC Microgrid Technology: System Architectures, AC Grid Interfaces, Grounding Schemes, Power Quality, Communication Networks, Applications, and Standardizations Aspects , 2017, IEEE Access.

[7]  Claudinor B. Nascimento,et al.  Performance comparison between nonlinear and linear controllers applied to a buck converter using poles placement design , 2013, 2013 15th European Conference on Power Electronics and Applications (EPE).

[8]  Jun Yang,et al.  Finite-Time Output Feedback Control for PWM-Based DC–DC Buck Power Converters of Current Sensorless Mode , 2017, IEEE Transactions on Control Systems Technology.

[9]  R. Iravani,et al.  Microgrids management , 2008, IEEE Power and Energy Magazine.

[10]  Weidong Xiao,et al.  A Novel Droop-Based Average Voltage Sharing Control Strategy for DC Microgrids , 2015, IEEE Transactions on Smart Grid.

[11]  Dong Chen,et al.  Control and Operation of a DC Microgrid With Variable Generation and Energy Storage , 2011, IEEE Transactions on Power Delivery.

[12]  Amir Khorsandi,et al.  A Decentralized Control Method for a Low-Voltage DC Microgrid , 2014, IEEE Transactions on Energy Conversion.

[13]  G. Ledwich,et al.  Modelling and control of switch-mode DC-DC converters using state transition matrices , 1995 .

[14]  S. Eshtehardiha,et al.  Optimizing LQR and pole placement to control buck converter by genetic algorithm , 2007, 2007 International Conference on Control, Automation and Systems.