Resilience-Driven Modeling, Operation and Assessment for a Hybrid AC/DC Microgrid

Abstract

High-impact and low-probability extreme events can cause severe damage to power systems, especially for distribution systems. Microgrids (MGs) with distributed generation resources provide a viable solution for local load survivability via islanding schemes during extreme events. Recently, much research has focused on resilience-driven modeling and operations of MGs. In this paper, a resiliencedriven operational model incorporating two operational modes (grid-connected and islanded) and detailed technical characteristics, such as voltage-related operational constraints, is developed for the resilience enhancement of a hybrid AC/DC MG. A detailed AC optimal power flow (OPF) algorithm is employed to model operational constraints and the power exchange between AC and DC subgrids. Preventive power importing is utilized for better preparedness before extreme events and demand response is employed to reduce load shedding during emergency mode. Existing literature on resilience assessment is reviewed and a modified multi-phase curve is proposed to fully represent the influence of limited generation resources and uncertain event duration on resilience. Extensive case studies capturing the distinction of critical loads and non-critical loads and two types of contingencies (multiple line faults and interrupted connection between AC subgrid and DC subgrid) are conducted to demonstrate the effectiveness of the proposed resilience strategy on protecting critical loads and reducing total load shedding. Particularly, a sensitivity analysis considering different event occurrence time has been simulated to capture, in a simple but rather effective way, the effect of the uncertainty surrounding event occurrence.

Resilience assessment methodologies and enhancement strategies of multi‐energy cyber‐physical systems of the distribution network

“…(3) Fragility model of DGs DGs are less affected by typhoon disasters and can provide power to support the MESs islanding operation [51,115,[117][118][119][120][121]. DGs' fragility model can be expressed by the failure probability of the normal operation of the system as follows: The indoor facilities of MECPSs, such as gas turbine, P2G, gas triple supply, energy storage, and other physical system equipment and cyber system equipment (protection and measurement) are indoor, which are less affected by the typhoon.…”

Resilience Improvement of Distribution Networks Using a Two-Stage Stochastic Multi-Objective Programming via Microgrids Optimal Performance

“…Load restoration-based methods are another purpose of increasing resilience that has been used in [19]. MGs with DG are introduced as a viable solution in [20], [21] for local load survivability during contingencies due to their islanding schemes. In this regard, according to a hybrid AC/DC MG resilience enhancement, a resilience-driven approach is presented in emergency and normal operation mode.…”

Resiliency-Driven Approach of DC Microgrid Voltage Regulation Based on Droop Index Control for High Step-Up DC-DC Converter

“…A comprehensive review on various control strategies in hybrid AC/DC microgrid is reported [4] where an extensive review covering various aspects such as modeling, energy management, and stability analysis is presented. Similarly, a DC microgrid with both grid and islanded modes is studied in detail [5] by conducting case studies to validate the resilience-based efficacy of the proposed approach. e authors in [6] implemented a resiliencybased approach by incorporating a battery energy storage system (BESS) with the existing grid-connected microgrid to address the critical loads (CLs) during grid outage conditions to ensure stable operation of hybrid AC/DC microgrid.…”