In this chapter, we will focus on the primary and secondary controls for proper power sharing and set-point restoring operations of MGs. Traditionally, the power sharing is achieved by the decentralized droop scheme of each DIC. Although proper real power sharing can be achieved in most existing methods, incorrect reactive power sharing has been observed. In recent years, advocates of distributed multiagent systems (MAS) have been broadly adopted as promising solutions for MG control and operations. Under this framework, the primary control and the secondary control can be efficiently integrated into a single distributed task.

Chapter Contents:

• 10.1 Introduction
• 10.1.1 Average consensus-based droop control
• 10.1.2 Distributed pining-based droop control
• 10.2 Droop control in isolated AC MGs
• 10.2.1 Problem formulation
• 10.2.2 Model descriptions
• 10.3 Average consensus through ADMM
• 10.3.1 Basic concepts
• 10.3.2 Distributed implementations
• 10.3.2.1 Method A
• 10.3.2.2 Method B
• 10.4 Consensus-based droop control
• 10.4.1 Optimal stable equilibrium point
• 10.4.2 Consensus optimization
• 10.4.3 ADMM implementations
• 10.4.3.1 Method A
• 10.4.3.2 Method B
• 10.4.4 ADMM implementations with flexible droop gain ratios
• 10.5 Stability analysis of closed-loop MG systems with consensus-based droop-controlled VSGs
• 10.5.1 P - f / Q - V droop
• 10.5.2 ADMM implementations
• 10.5.3 ADMM implementations with flexible droop gain ratios
• 10.6 Real-time simulations of ADMM-based consensus droop control
• 10.7 Distributed pinning control
• 10.7.1 Basic concepts
• 10.7.2 Distributed pinning control
• 10.8 Distributed pinning-based droop control
• 10.8.1 MAS development
• 10.8.2 Pinning localization and grid partition
• 10.8.3 Pinning-based droop control
• 10.8.4 Stability criteria
• 10.9 Simulation verifications of the pinning-based droop control
• 10.9.1 Test-bed descriptions and partition
• 10.9.1.1 System development and testing
• 10.9.1.2 Simulation results
• 10.9.2 Possible limitations
• 10.10 Conclusions
• Appendix A Formulations of M, D, A, and Af
• Appendix B Validity of EF W(y,z)
• References

Inspec keywords: power convertors; power distribution control; voltage control; power generation control; distributed power generation

Other keywords: set-point restoring operations; interface converters; distributed multiagent systems; reactive power sharing; secondary control; alternating direction multipliers method; microgrid control; isolated AC microgrids; distributed energy resources; power sharing; ADMM-based consensus droop control; decentralized droop scheme; distributed pinning droop control; primary control; MAS

Subjects: Power system control; Power convertors and power supplies to apparatus; Distributed power generation; Control of electric power systems; Voltage control; Power electronics, supply and supervisory circuits