20 research outputs found
Component Outage Estimation based on Support Vector Machine
Predicting power system component outages in response to an imminent
hurricane plays a major role in preevent planning and post-event recovery of
the power system. An exact prediction of components states, however, is a
challenging task and cannot be easily performed. In this paper, a Support
Vector Machine (SVM) based method is proposed to help estimate the components
states in response to anticipated path and intensity of an imminent hurricane.
Components states are categorized into three classes of damaged, operational,
and uncertain. The damaged components along with the components in uncertain
class are then considered in multiple contingency scenarios of a proposed
Event-driven Security-Constrained Unit Commitment (E-SCUC), which considers the
simultaneous outage of multiple components under an N-m-u reliability
criterion. Experimental results on the IEEE 118-bus test system show the merits
and the effectiveness of the proposed SVM classifier and the E-SCUC model in
improving power system resilience in response to extreme events
Fault Point Detection for Recovery Planning of Resilient Grid
Large-scale meteorological disasters are increasing around the world, and
power outage damage by natural disaster such as typhoons and earthquakes is
increasing in Japan as well. Corresponding to the need of reduction of economic
losses due to power outages, we are promoting research of resilient grids that
minimizes power outage duration. In this report, we propose PACEM (Poles-Aware
moving Cost Estimation Method) for determining travel costs between failure
points based on the tilt angle and direction of electric poles obtained from
pole-mounted sensors and road condition data. Evaluation result shows that the
total recovery time can be reduced by 28% in the target area
Progressive damage assessment and network recovery after massive failures
After a massive scale failure, the assessment of damages to communication networks requires local interventions and remote monitoring. While previous works on network recovery require complete knowledge of damage extent, we address the problem of damage assessment and critical service restoration in a joint manner. We propose a polynomial algorithm called Centrality based Damage Assessment and Recovery (CeDAR) which performs a joint activity of failure monitoring and restoration of network components. CeDAR works under limited availability of recovery resources and optimizes service recovery over time. We modified two existing approaches to the problem of network recovery to make them also able to exploit incremental knowledge of the failure extent. Through simulations we show that CeDAR outperforms the previous approaches in terms of recovery resource utilization and accumulative flow over time of the critical service
Optimizing Service Restoration in Distribution Systems with Uncertain Repair Time and Demand
This paper proposes a novel method to co-optimize distribution system
operation and repair crew routing for outage restoration after extreme weather
events. A two-stage stochastic mixed integer linear program is developed. The
first stage is to dispatch the repair crews to the damaged components. The
second stage is distribution system restoration using distributed generators,
and reconfiguration. We consider demand uncertainty in terms of a truncated
normal forecast error distribution, and model the uncertainty of the repair
time using a lognormal distribution. A new decomposition approach, combined
with the Progressive Hedging algorithm, is developed for solving large-scale
outage management problems in an effective and timely manner. The proposed
method is validated on modified IEEE 34- and 8500-bus distribution test
systems.Comment: Under review in IEEE Transactions on Power System
Overcurrent relays coordination optimisation methods in distribution systems for microgrids: a review
Electric power networks connected with multiple distributed generations (microgrids) require adequate protection coordination. In this paper, the overcurrent relay coordination concept in distribution system has been presented with details. In this available literature, the previous works on optimisation methods utilised for the coordination of over current relays; classification has been made based on the optimisation techniques, non-standard characteristics, new constraints that have been proposed for optimal coordination and dual setting protection schemes. Then a comprehensive review has been done on optimisation techniques including the conventional methods, heuristic and hybrid methods and the relevant issues have been addressed
On critical service recovery after massive network failures
This paper addresses the problem of efficiently restoring sufficient resources in a communications network to support the demand of mission critical services after a large-scale disruption. We give a formulation of the problem as a mixed integer linear programming and show that it is NP-hard. We propose a polynomial time heuristic, called iterative split and prune (ISP) that decomposes the original problem recursively into smaller problems, until it determines the set of network components to be restored. ISP's decisions are guided by the use of a new notion of demand-based centrality of nodes. We performed extensive simulations by varying the topologies, the demand intensity, the number of critical services, and the disruption model. Compared with several greedy approaches, ISP performs better in terms of total cost of repaired components, and does not result in any demand loss. It performs very close to the optimal when the demand is low with respect to the supply network capacities, thanks to the ability of the algorithm to maximize sharing of repaired resources