Customer Outage Research Articles

Research on Pole-climbing Robots that Can Perform Multi-degree-offreedom Motion and Working at the Top of Distribution Network Poles

Background: In order to complete power maintenance, equipment renewal and other loss reduction work and reduce customer outage time at the same time, live electrical work has become a necessary means. Pole-climbing robots, as an important auxiliary tool for power-carrying operations, frequently appear in papers and patents. Objective: The pole climbing robot is designed to work at any position in the working space with electric distribution pole, effectively and safely replacing manual work. Methods: Based on the physical parameters of the cement utility pole and the range of space for live electrical work, the functional relationships are established between the structural parameters of the robot and the kinematic and dynamical models, and the optimal range of parameters is solved. Results: The robot can rotate and climb around the pole with five steering angles: 0°, 22.5°, 45°, 67.5° and 90°. The control insulated operating rod can transport special tools to any station within 1m radius of the distribution pole for live work. It has a maximum load of 11kg and a maximum climbing speed of 33.6mm/s. Conclusion: The pole-climbing robot can climb cement utility pole, manipulate the insulated operating lever it carries, and transport special tools to the workstation on the cable for carrying out live electrical work.

Probabilistic Storm and Electric Utility Customer Outage Prediction

Probabilistic Storm and Electric Utility Customer Outage Prediction

Distributed fault-passage indicators versus central fault location: Comparison for reliability centred planning of resonant-earthed distribution systems

Fault location methods are crucial for reducing fault restoration time, and thus improving a network’s system average interruption duration index (SAIDI) and customer outage cost. Resonant-earthed systems pose problems for traditional fault location methods, leading to poor accuracy and a need for additional complexity. In this context, methods that detect fault direction (fault-passage indicators, FPI) at multiple points in the network may show advantages over a central distance-estimation method using fault locators (FL) of poor accuracy. This paper includes a comparative study of these two major fault location methods, comparing the reliability benefit from a varied number of FPIs or a central method. The optimal placement of the fault locating devices is found by formulating a mixed-integer linear programming (MILP) optimization approach that minimizes both outage and investment costs and assesses SAIDI. This approach has been tested on an example distribution system. However, to justify the universality of the algorithm, the RBTS reliability test system has also been analysed. The comparison of location methods and placement method of FPIs are useful for reliability centred planning of resonant-earthed distribution systems where fault location is to be used. Results show that a small number of FPIs that give accurate identification of direction may give more cost effective increase in reliability than a distance estimate by FL with typical levels of inaccuracy.

Risk assessment in distribution networks considering cyber coupling

With the continuous development of information and communication technologies and their wide application in distribution networks, which have evolved into cyber-physical distribution systems (CPDS). Yet, interactions between cyber and physical systems mean power systems face a greater potential risk. Since feeder automation (FA) systems in a CPDS can quickly isolate faults and restore services, to reduce customer outage times, the potential effect of cyberattacks on FA systems is massive. This paper proposes a risk assessment method for cyberattacks in distribution networks considering cyber coupling. The proposed method takes into account the impacts of cyber systems on power systems, and vice versa. Regarding the cyberattack, an attack method to mislead the judgment of FA systems by tampering with monitoring data of remote terminal units (RTUs) is analyzed, and a Bayesian attack graph (BAG) model is adopted to quantify the successful probability of RTUs. To calculate the attack consequences, a power supply restoration model considering the interdependence of cyber and physical systems is developed, which is measured in scale and in duration to full restoration. The proposed methodology is tested and validated using the modified IEEE 33-node and CPS 62-node test systems. This study highlights the importance of assessing distribution network security from the cyber-physical point of view.

A NEW METHOD FOR ANALYSING FINANCIAL DAMAGES CAUSED BY GRID FAULTS ON INDIVIDUAL CUSTOMERS

Disruptions in electricity supply can cause significant social and economic damages to individual customers connected to the electricity grid, causing loss of income, productivity, and material damages. In this context, considerable investments are required for improving the reliability of the electricity network, and appropriate methods are needed for evaluating the cost-benefit of such investments. This paper proposes a new method for analysing financial damages caused by loss of electricity supply for individual customers, consisting of (i) a model for representing individual customers and their grid connection, and (ii) a method for expressing the reliability of a grid connection in terms of financial damages caused by the loss of electricity supply, defined as Customer Outage Cost, CCOST. These two proposed approaches are combined in a probabilistic method for evaluating the economic impacts of grid faults on individual customers. Representing grid reliability in financial terms supports the decision-making process of improving the reliability of electricity supply. The methodology is tested with a case study for a rural dairy farm in Finland, where two alternatives for improving the reliability of electricity supply are evaluated: investments in underground cables and in a microgrid, including a cost-benefit analysis of these investments against their yielded reduction in CCOST. The results from the case study show that the proposed methodology appropriately represents an individual customer and its grid connection reliability. In the context of this study, the microgrid approach was the most cost-effective alternative to mitigate the customer damages incurred by grid faults.

Stochastic Planning and Operational Constraint Assessment of System-Customer Power Supply Risks in Electricity Distribution Networks

Electricity-distribution network operators face several operational constraints in the provision of safe and reliable power given that investments for network area reinforcement must be commensurate with improvements in network reliability. This paper provides an integrated approach for assessing the impact of different operational constraints on distribution-network reliability by incorporating component lifetime models, time-varying component failure rates, as well as the monetary cost of customer interruptions in an all-inclusive probabilistic methodology that applies a time-sequential Monte Carlo simulation. A test distribution network based on the Roy Billinton test system was modelled to investigate the system performance when overloading limits are exceeded as well as when preventive maintenance is performed. Standard reliability indices measuring the frequency and duration of interruptions and the energy not supplied were complemented with a novel monetary reliability index. The comprehensive assessment includes not only average indices but also their probability distributions to adequately describe the risk of customer interruptions. Results demonstrate the effectiveness of this holistic approach, as the impacts of operational decisions are assessed from both reliability and monetary perspectives. This informs network planning decisions through optimum investments and consideration of customer outage costs.

Preparatory Operation of Automated Distribution Systems for Resilience Enhancement of Critical Loads

This paper proposes a stochastic optimization model for preparatory operation of distributed energy resources that enhance the resilience of critical loads against extreme weather events. Adopting hurricanes as a case study of extreme weather events, a high-precision spatio-temporal hurricane impact analysis model is first developed to enhance the situational awareness of automated distribution systems and generate a set of hurricane-induced outage scenarios. A stochastic mixed-integer conic programming model is then developed for co-optimizing the preparatory schedule of distributed energy storage and distributed generation ahead of hurricane along with post-event decisions of restoring services to customers, while minimizing the expected cost of energy not served as the index to measure the resilience. The proposed model prioritizes the service restoration of critical loads by integrating customer interruption cost function, which captures the customer type and outage costs as well as interruption duration in making restoration decisions. Additionally, a conic power flow model is adopted to accurately capture network operation constraints in pre- and post-outage scenarios. Numerical results conducted on the IEEE 33-bus system show that the proposed model can enhance the performance of automated distribution systems in responding to hurricane-induced outages by efficiently utilizing grid resources to improve the resilience of critical loads.

Research on Efficient Collection Method of Blackout Data in Distribution Network

Based on the power supply management needs of power supply companies, this paper adopts a big data-driven power outage data collection method to build a scientific customer outage time key indicator around the power grid comprehensive customer service system, establish a customer outage time indicator responsibility system, and establish a customer outage The process monitoring platform has formed a data-driven customer power outage analysis system to effectively handle customer power outages.

Development of a Typhoon Power Outage Model in Guangdong, China

In this study, typhoon power outage models were developed to predict the number of customer outages and damaged poles in Xuwen, Guangdong, China using data from three typhoons: Rammasun, Kalmaegi and Mujigae. Our hold-out validation demonstrates that these models can accurately estimate the number of customer outages and damaged poles from typhoons. The mean relative error is 5.1% in the customer outage model and 9.6% in the pole damage model. This study has two key improvements over previous work. First, our models provide more accurate predictions through leveraging a variety of static and dynamic variables that characterize the typhoon hazard and local environmental conditions. Maximum gust wind speed, elevation, land cover and duration of strong winds are the four most important variables for both the customer and pole models. Second, we demonstrate that it is possible to provide skillful predictions of power outages at 1-km resolution. This is a significantly higher spatial resolution than past tropical cyclone power outage models. The models will be used to support improved decision making. The operational power outage forecasts will be used by the electrical utility for pre-positioning crews and materials and to notify customers who are likely to lose power.

Analyzing Customer Outage Cost in a Microgrid

In today’s era of socioeconomic and environmental concerns, conventional energy sources are incapable of meeting increasing energy demands which leads to the significance of Microgrid (MG) systems incorporating renewable energy sources. An ideally designed microgrid capable of operating in standalone and grid connected mode is considered with photovoltaic panels, wind turbines, fuel cell, battery and Microturbines (MT) as sources. The two noteworthy disadvantages of microgrid are very expensive power supply and intermittency of power generation. Besides ensuring a steady supply, the power delivered should be of moderate cost. So, this work focuses on reducing the cost associated with its operation and emission by simultaneously analyzing the impact of uncertainty. The uncertainties can be caused due to different DGs present in MG and the load varations. The variations of uncertainty are included as outage cost. The MG operating under islanded and grid connected modes are analyzed for different scenarios to obtain optimal value of customer outage cost and operating cost. So a heuristic optimization technique which can handle the multi-objective problem is considered. The optimal solution for different operational scenarios of grid connected and islanded mode are obtained using Multi-Objective Particle Swarm Optimization (MOPSO) algorithm.

Mixed-Integer Nonlinear Programming Formulation for Distribution Networks Reliability Optimization

An optimal placement of protective devices could increase the reliability and quality level of a distribution network. An innovative mixed-integer nonlinear programming model is proposed in this paper to find the type, optimal siting, and number of protective devices to be accurately installed in distribution networks. The customer outage and protective devices costs are considered to derive a value-based reliability equation. To ensure the effectiveness of the proposed formulation economic and technical constraints is considered. Further, this paper aims at aiding decision-makers in providing appropriate protective device allocation by minimizing the expected interruption cost index. Case studies are employed to demonstrate the reliability optimization of a test network and a typical real-size network in which the several cost constraints and protection schemes are assumed to extract the results. Accuracy and effectiveness of the proposed method are assessed and sensitivities analysis is carried out.

Optimal selection switching of remote terminal unit using reliability index in electric power distribution systems

Remote terminal units (RTUs) can trip the circuit in case of a fault in a power system when work with the central control room. RTUs are used to monitor faults at different parts of the power system. This paper presents optimal placement of RTUs by using Particle Swarm Optimization (PSO) technique to minimize customer outage, travel costs and improve System Average Interruption Duration Index (SAIDI). The method is applied to IEEE 13 Node Test Feeder. The Results show as the number of RTUs installed in nodes with many customers is increased, SAIDI improves.

OPTIMAL SIZING AND SITING OF DG RESOURCES AT 63KV/20KV SUBSTATIONS CONSIDERING THE EFFECT OF EARTHQUAKE ON TECHNICAL AND ECONOMIC PARAMETERS

The Iranian Ministry of Energy commands the Regional Electrical Companies to install DG resources at 63kV/20kV substations and at the end of 20kV lines. The first and foremost challenge in installing these resources is deciding on the optimal place and capacity of these resources. This paper is aimed to propose an appropriate algorithm for siting and sizing such resources in Bakhtar Regional Electrical Company. The proposed algorithm takes into consideration all technical and economic factors important to the company. Due to the variety of important factors in sizing and siting, this paper proposes a new method to reduce limitations and constraints of this process. Accordingly, all technical and economic factors are assigned monetarily, so violating limitations reduces considered benefits. This method increases the probability of convergence of results and accordingly is appropriate for application in actual network where there are numerous factors. Another feature of this paper is considering the parameter of earthquake for the first time and is assigned monetarily according to its devastating effects on considered parameters. Applying this parameter while sizing and siting leads to increase in distributed generation impacts in reducing customer outage in locations with high probability of earthquake. The obtained results are reported and discussed.

Research on Construct of Energy Management Platform Based on Marketing and Distribution Integrated System

Marketing and Distribution Integrated System is based on GIS systems, and a unified information model of power grid equipment, basic data and topology-based systems, the use of high-tech information technology, application management and distribution line losses quarter field of network construction planning, customer outage management and other integrated information platform. Energy management system implementation ultimate goal is to achieve through intelligent system integration of existing systems be saving energy consumption and improved. In automation technology and IT based on the establishment of energy management systems, based on objective data, metallurgical, chemical, thermal, power plants and other energy consuming enterprises, energy saving most fundamental way to implement. The foundation and core of this system is that the data distribution network GIS platform, integrated measurement automation, distribution network of production, distribution network planning, distribution network automation, distribution network engineering, marketing and other systems supporting the management and reliability of power supply and distribution network planning decisions Camp with information query formulated meter reading routes and other services.

Low-Voltage DC Distribution—Utilization Potential in a Large Distribution Network Company

Low-voltage direct-current (LVDC) distribution is a promising solution whose benefits are large power transfer capacity with low voltage, high cost savings potential, and improvements to reliability and voltage quality. Tests by the pilot implementation in the distribution system operator (DSO) Elenia Oy have given promising results. The power transfer capacity of the system has been calculated in this paper using voltage drop and maximum load of cable as boundaries. The branches of the medium-voltage network that can be replaced by LVDC distribution are determined based on the calculations and mass computation of the entire distribution area of Elenia Oy. Based on the electrotechnical and customer outage costs (COC) analyses made, it can be inferred that LVDC distribution has good utilization potential. Based on the power transfer capacity calculations, it is technically possible to replace branch lines up to 8 km long by LVDC distribution which means about 20% of the total medium-voltage network length in the distribution area of Elenia Oy. This means also huge potential in improving the overall reliability of electricity supply and in reducing outage costs of customers which are these days taken into account in the regulation of network business.

An Analytical Adequacy Evaluation Method for Distribution Networks Considering Protection Strategies and Distributed Generators

Reliability evaluation relates to the impact of faults on customer outage frequency and time. Thus, studying the process of fault isolation and supply restoration is critical in reliability evaluation. In distribution systems, distributed generators (DGs), especially renewable DGs, are increasingly integrated into the network. New issues emerge after DG integration: 1) DG reliability model; 2) change of protection strategy and supply restoration process; and 3) islanding operation. In this paper, an analytical method is proposed to assess the distribution system reliability level considering these issues. The reliability model for DG and load are developed using scenarios reduction techniques based on historical data. The correlation between renewable resources and load is also formulated in the model. When a fault occurs in a distribution system, parts of the distribution system can be operated as islands. The reliability indices of the load point in the microgrid vary according to the power adequacy assessment in the island and supply restoration process. To improve calculation efficiency, the analysis of fault isolation and supply restoration process and reliability evaluation is based on segments instead of single components. Then, the overall reliability evaluation framework is proposed. In the end, a detailed case study is presented.

Automation Effects on Reliability and Operation Costs in Storm Restoration

—Storm response and restoration can be very expensive for electric utilities. The deployment of automated switches can benefit the utility by decreasing storm restoration hours. The automated switches also improve system reliably by decreasing customer interruption duration. In this article, a Monte Carlo simulation is used to mimic storm equipment failure events, followed by reconfiguration for restoration and power flow evaluations. The customer outage status and duration are examined. Changes in reliability for the system with and without automated switching devices are investigated. Economic benefits of utilizing smart grid automated devices are considered.

Optimal Distribution Network Automation Considering Earth Fault Events

In the past decade, distribution network operators have been broadly engrossed toward automated distribution networks. The operators acknowledge network automation as an efficient investment toward a better service reliability. This paper aims to provide a new long-term cost/benefit analysis for an optimal level of distribution network automation. In the analysis, reduction in customer outage cost is considered as the benefit of implementing automation systems with capital investment, and annual operation and maintenance costs. In the Finnish regulation model, there is a special incentive based on customer outage cost reduction. As the main contribution of this paper, the impact of earth fault events and their required time-consuming fault management process is taken into account within the calculation of the benefit of automation systems. The solution of the analysis consists of the optimal number and location of remote-controlled sectionalizing switches, which are building blocks of automation systems. The problem is formulated in a mixed-integer linear programming format that can be effectively solved by commercially available solvers. The effectiveness of the proposed algorithm is demonstrated by applying it to the Helsinki distribution network. The results show that neglecting the impact of earth fault events can lead to suboptimal solutions.

Research on Energy Management Platform Based on Marketing and Distribution Integrated System

Marketing and Distribution Integrated System is the use of modern information technology, on the basis of a unified enterprise network equipment and customer information model, basic information and topological relationship, used in customer-facing supply reliability management, customer outage management, line loss of four sub-management, business expanding auxiliary field and distribution network construction planning decisions such as the standardization of GIS-based, integrated enterprise-wide information platform. This paper describes a GIS-based business integration system with the main content and functionality, energy efficiency management system to achieve a variety of integrated business systems and energy efficiency management decision-making system that can effectively address the development of enterprise information supply information silos that exist , huge amounts of data and processes curing problems with the integration of power supply enterprise business planning and construction of information systems provide a useful reference.

The Relationship among the Security, Efficiency and Adequacy of Electrical Power Grid Based on the Novel Evaluation Method

In order to study out the incidence relationship among security, efficiency and adequacy of Electrical Power Grid, a novel analyze model considering grid evolution and a relationship evaluation method is proposed in this paper. The model incorporates in fast dynamic and slow evolution. The former is based on an improved OPA model with low frequency load shedding control and the outage risk calculation. The latter is consists of increasing load, up-grading and constructing equipments including power plants, transformers and transmission lines, Using the model simulation the power grid development process. Based on the model, the customer outage risk caused by cascading failure is obtained in several times, the efficiency index and grid scale index are solved at the same times, these data are the basic data for analyze the incidence relationship among the security, efficiency and adequacy of electrical power grid. In this paper, the power grid of Kaifeng City in Henan Province, of China is used to simulate the evolution. The results show that the relationship among the security, efficiency and adequacy of grid is as exponential function, and a reasonable range of efficiency and adequacy of grid are proposed.