A Multi-Agent-Based Self-Healing Framework Considering Fault Tolerance and Automatic Restoration for Distribution Networks

Lin Guan,Lingxue Lin,Hengan Chen

doi:10.1109/access.2021.3055284

Lin Guan, Lingxue Lin + Show 1 more

Open Access

https://doi.org/10.1109/access.2021.3055284

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Abstract

Increasing penetration of distributed generators (DGs) brings new challenges to the control and protection of distribution networks. This article proposes a control and protection framework based on Multi-agent System (MAS), in which situation awareness of zone agents plays an important role. The main protection is designed to locate and isolate faults based on the peer-to-peer communication among the zone agents. Fault-tolerant mechanisms, including self-inspection and backup protection, are developed to cope with the malfunction of individual MAS and local communication failure. An automatic parallel restoration scheme that doesn’t require complete grid information is proposed to restore the power supply. Comprehensive simulation studies are carried out on a 71-bus distribution network with DGs using DIgSILENT, and the results have shown the effectiveness of the proposed self-healing framework.

Highlights

The penetration level of distributed generators (DGs) in electricity distribution networks increases rapidly, which converts the power flow in the distribution network from the traditional unidirectional mode into a bidirectional one [1]
THE AUTOMATIC NETWORK RESTORATION SCHEME In the open-loop operation mode, after the zone agent (ZA) cut off the fault line, the downstream zones will be isolated from the main grid
All the agents share the same protection and control strategies and require no global information about the interconnected feeder group to make decision, which simplifies the deployment of the system

Summary

INTRODUCTION

The penetration level of distributed generators (DGs) in electricity distribution networks increases rapidly, which converts the power flow in the distribution network from the traditional unidirectional mode into a bidirectional one [1]. Guan et al.: Multi-Agent-Based Self-Healing Framework Considering Fault Tolerance and Automatic Restoration been widely applied in the transmission system [10] and the MAS-based wide-area backup protection gains much interest recently [11]–[13] Different information, such as the differential current [11], directional distance [12], are collected for centralized decision. (3) Abnormal Situation (A): In the abnormal situation, the power supply is not interrupted, but some abnormal events are detected, such as the failures of the communication system (A01) or sensors (A02) In this situation, the ZA may lock part of its functions and inform the monitoring system as well as the neighbor ZAs. The typical criteria for situational judgment are presented, where Im is the current flowing through branch m, Vj is the voltage of bus j, Vmin and Vmax are the minimum and maximum limits of bus voltage, and Iset is over-current protective setting. The proposed primary protection scheme is adaptive to different topologies and operation modes

SELF-CHECKING MECHANISM

THE AUTOMATIC NETWORK RESTORATION SCHEME

CONCLUSION