Logo
ScienceStack
Table of Contents
Fetching ...
Sign In

Restricting Voltage Deviation of DC Microgrids with Critical and Ordinary Nodes

Handong Bai, Peng Li, Hongwei Zhang

Abstract

Restricting bus voltage deviation is crucial for normal operation of multi-bus DC microgrids, yet it has received insufficient attention due to the conflict between two main control objectives in DC microgrids, i.e., voltage regulation and current sharing. By revealing a necessary and sufficient condition for achieving these two objectives, this paper proposes a compromised distributed control algorithm, which regulates the voltage deviation of all buses by relaxing the accuracy of current sharing. Moreover, for a class of DC Microgrids consisting of both critical nodes and ordinary nodes, this paper proposes a distributed control algorithm that restricts the voltage deviation of critical nodes and simultaneously keeps the current sharing of ordinary nodes. This algorithm also works under plug-and-play settings. Simulations illustrate our theory.

Restricting Voltage Deviation of DC Microgrids with Critical and Ordinary Nodes

Abstract

Restricting bus voltage deviation is crucial for normal operation of multi-bus DC microgrids, yet it has received insufficient attention due to the conflict between two main control objectives in DC microgrids, i.e., voltage regulation and current sharing. By revealing a necessary and sufficient condition for achieving these two objectives, this paper proposes a compromised distributed control algorithm, which regulates the voltage deviation of all buses by relaxing the accuracy of current sharing. Moreover, for a class of DC Microgrids consisting of both critical nodes and ordinary nodes, this paper proposes a distributed control algorithm that restricts the voltage deviation of critical nodes and simultaneously keeps the current sharing of ordinary nodes. This algorithm also works under plug-and-play settings. Simulations illustrate our theory.
Paper Structure (25 sections, 47 equations, 7 figures)

This paper contains 25 sections, 47 equations, 7 figures.

Table of Contents

  1. Introduction
  2. Preliminary
  3. Notation
  4. Graph theory
  5. DC microgrid model
  6. Conflict of voltage consensus and current sharing
  7. Voltage-current compromised control
  8. Problem formulation
  9. Compromised control law design
  10. Steady state analysis
  11. Voltage deviation restriction
  12. Voltage balancing and compromised control of critical nodes
  13. Critical node, ordinary node, and problem formulation
  14. Average voltage estimation for critical nodes
  15. Compromised control for critical nodes
  16. ...and 10 more sections

Figures (7)

  • Figure 1: Electrical scheme of the $i$-th DG
  • Figure 2: Control block diagram of the DC microgrid with respect to controller \ref{['e_ctrlscheme1']} and \ref{['e_newcompromise']}
  • Figure 3: Kron reduction for the communication network of a DC microgrid with 7 buses
  • Figure 4: DC microgrid with 7 buses
  • Figure 5: Simulation results of Case I. The shaded area corresponds to the admissible voltage range for all nodes.
  • ...and 2 more figures