Payman Dehghanian

Critical Component Identification in Reliability Centered Asset Management of Power Distribution Systems Via Fuzzy AHP

Confronted with the power system restructuring trend reforming the past-regulated power systems, the need for a narrower insight on the costly maintenance strategies seems imperative. It falls within the realm of reliability centered maintenance to enhance the cost effectiveness of power distribution maintenance policies. From a practical point of view, this paper devises a novel approach on the basis of the analytical hierarchical process (AHP) accompanied by fuzzy sets theory to determine the most critical component types of distribution power systems to be prioritized in maintenance scheduling. In the presence of many qualitative and quantitative attributes, fuzzy sets can effectively help to deal with the existent uncertainty and judgment vagueness. As demonstrated in a practical case study, the proposed fuzzy AHP method introduces its applicability and efficiency in the asset management procedure.

Multiagent Genetic Algorithm: An Online Probabilistic View on Economic Dispatch of Energy Hubs Constrained by Wind Availability

Multiple energy carriers (MECs) have been broadly engrossing power system planners and operators toward a modern standpoint in power system studies. Energy hub, though playing an undeniable role as the intermediate in implementing the MECs, still needs to be put under examination in both modeling and operating concerns. Since wind power continues to be one of the fastest-growing energy resources worldwide, its intrinsic challenges should be also treated as an element of crucial role in the vision of future energy networks. In response, this paper aims to concentrate on the online economic dispatch (ED) of MECs for which it provides a probabilistic ED optimization model. The presented model is treated via a robust optimization technique, i.e., multiagent genetic algorithm (MAGA), whose outstanding feature is to find well the global optima of the ED problem. ED once constrained by wind power availability, in the cases of wind power as one of the input energy carriers of the hub, faces an inevitable uncertainty that is also probabilistically overcome in the proposed model. Efficiently approached via MAGA, the presented scheme is applied to test systems equipped with energy hubs and as expected, introduces its applicability and robustness in the ED problems.

A Comprehensive Scheme for Reliability-Centered Maintenance in Power Distribution Systems—Part II: Numerical Analysis

The aim of this two-part paper is to present a comprehensive reliability-centered maintenance framework tailored to power distribution systems. The first paper discusses the fundamental concepts, presents the developed algorithm, and introduces the required mathematical formulations. This second paper is focused on the application of the proposed methodology on a real distribution system. Considerable effort is devoted to examine the proposed method in a step-by-step manner to clarify the implementation procedure. The required data for the procedure are taken from available references and follow reasonable technical assumptions. Practical aspects are incorporated, and the results obtained are thoroughly discussed. The concluding remarks are outlined to summarize the paper set which also brings to light superiorities of the proposed scheme.

Reliable Implementation of Robust Adaptive Topology Control

The topology (transmission line) switching to achieve economic and reliability gains in the power grid has been proposed some time ago. This approach did not gain much attention until recently when large penetration of renewable generation created incentives to use transmission line switching to control sudden changes in power flows and mitigate contingencies caused by the generation variability. This paper explores implementation issues related to circuit breaker (CB) monitoring, relay setting coordination and detection of relay misoperations in the context of the topology switching sequence implementation. The paper covers risk-based assessment of CB status needed for determination of reliable switching sequences; it indicates how relay settings may be changed due to switching actions; it also provides an on-line algorithm for detection of relay misoperations, which identifies the lines that may be switched back to service after being trip erroneously by a relay.

PHEVs centralized/decentralized charging control mechanisms: Requirements and impacts

This paper investigates the main features of the PHEV centralized and decentralized charging control mechanisms, their requirements and also impacts on distribution system performance. A home-based charging control scenario as well as a coordinated charging control algorithm for the charging management of PHEVs is devised in this paper. Both the owner preferences and system operator concerns are taken into consideration in an optimization-based framework. The total network losses and charging costs are set as the constraints to the proposed optimization approach. Various aspects of the two mechanisms are discussed and comprehensively compared by their application on the IEEE 34-bus test system. The obtained results and discussions offered demonstrate the efficiency and applicability of the proposed approach in real world.

Security-based circuit breaker maintenance management

Circuit breakers play a vital role in maintaining system security since their malfunctioning could result in further component outages and may lead to the insecure operating conditions. This paper proposes a new approach for identifying the most risky circuit breakers using the condition-based monitoring data and security-based impact evaluations. For a given substation configuration, those circuit breakers which cause line outages due to mal-operation during contacts opening are identified and analyzed. The security oriented risk indices taking into account both voltage violations and overloading conditions as the consequence of circuit breaker mal-operations are proposed. A new breaker maintenance prioritization scheme based on the risk factors is elaborated. The proposed security-based risk framework is deemed to be an efficient approach in both breaker maintenance planning and identification of the breakers which are unreliable for reconfiguration plans. The presented methodology is investigated and verified on the IEEE 14-bus test system.

Application of Game Theory in Reliability-Centered Maintenance of Electric Power Systems

As the electricity market undergoes continuous evolutions, along with the widely-recognized outdated nature of the grid, system operators would have to be able to more effectively manage the system operation expenses since waves of maintenance costs and equipment investments would be anticipated in a few years to come. Strategic implementation of cost-effective reliability-centered maintenance (RCM) approaches seems to be a key solution. This paper proposes an efficient method to assess the component criticality for system overall reliability and further maintenance focuses. A solution concept of game theory, called shapely value, is proposed that is able to fairly identify the contribution of every single equipments to the system reliability performance once a high-order contingency occurs under different loading conditions. The identified critical components are then systematically involved in a new optimization framework for effective scheduling of RCM implementation in power systems. The suggested framework helps in realizing where investments and maintenance to be made in the grid to ensure a desirable system reliability performance. Implemented on the IEEE reliability test system, the effectiveness of the suggested framework is confirmed by comparing to conventional techniques under various scenarios.

Probabilistic Decision Making for the Bulk Power System Optimal Topology Control

Power system topology control through transmission line switching for economic gains and reliability benefits has been recently considered in day to day operations. This paper introduces a probabilistic formulation for a more efficient application of topology control strategies in real world scenarios with anticipated increase in the presence of highly variable renewable generation and uncertain loads. Such uncertainties are modeled via the point estimation method embedded into the dc optimal power flow-based formulations for optimal switching solutions. Hourly and daily advantages of the proposed probabilistic framework, compared with the conventional operations and deterministic formulations, are discussed. As the anticipated economic gains would increase through sequential implementation of several switching actions, a new probabilistic decision making approach to identify the optimal number of switching actions at each hour is also proposed. This decision support tool uses the probabilistic reliability cost/value analytics in which not only the financial benefits, but also the costs of reliability risks, are taken into account. The approach is tested through various scenarios on the modified IEEE 118-bus test system, with and without renewables integration, and the results revealed its applicability and efficiency.

Circuit breaker operational health assessment via condition monitoring data

This paper presents a practical approach to evaluation of the operational health and reliability of circuit breakers in substations. Motivated by the recent failure surveys conducted by CIGRE working groups, circuit breaker condition data, obtained by monitoring critical parameters such as operational timings, tank gas pressure and temperature, mechanism traveling time and speed, etc., is used to evaluate the proposed health index. The proposed measure would help identify the transmission lines available for switching actions from the circuit breaker reliability view point. The proposed health index also provides a valuable input for substation maintenance personnel. The applicability of the proposed methodology is explored and validated using the actual circuit breaker condition data collected in the field.

Assessing circuit breaker life cycle using condition-based data

How to make decisions to optimally allocate the resources by deciding when to perform maintenance on power apparatus is a critical issue, especially with present economic scenario in power industry. This paper proposes a new approach to assess the circuit breakers life cycle or deterioration stages using its control circuit data. In this approach, the “classical” healthy, minor and major deterioration stages have been mathematically defined by setting up the limits of various performance indices. The model can be automatically updated as the new real-time condition-based data become available to assess the CBs operation performance using probability distributions. The methodology may also be used to quantify the effect of maintenance making use of the defined performance indices, which further helps in developing system-wide risk-based decision approaches for maintenance optimization. Case studies using field data recorded at different times during operations of circuit breaker are presented at the end.