Events that may test transmission grid resilience are varied. Some involve minimal
permanent damage and can be recovered from relatively quickly. Other events may require
much longer periods of time to recover where extensive damage has occurred. Some events
are fast to develop, while other may provide an opportunity to prepare (weather) or not
(willful attack).
Design and Mitigation Techniques of MV Capacitor Bank Switching Transients on...ijtsrd
This paper presents the techniques to mitigate transients caused by capacitor switching in the distribution system. It includes the theory of capacitive switching transients with different methods of mitigation. The paper uses MATLAB SIMULINK software package to simulate the specific mitigation devices. The mathematical calculations of different parameters such as transient voltages, current, and frequencies for each device are compared with obtained value from the simulations of each case study. Poonam Bhati | Mukesh Kumar Lodha ""Design and Mitigation Techniques of MV- Capacitor Bank Switching Transients on 132 KV Substation"" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-4 , June 2019, URL: https://www.ijtsrd.com/papers/ijtsrd25093.pdf
Paper URL: https://www.ijtsrd.com/engineering/electrical-engineering/25093/design-and-mitigation-techniques-of-mv--capacitor-bank-switching-transients-on-132-kv-substation/poonam-bhati
The capability of low-voltage ride-through (LVRT) of doubly fed induction generator (DFIG) has been considered as an essence for grid code requirements. Any unbalance on the grid side causes the rotor current of the generator to rise which leads to saturate the dc-link of the back-to-back converter or even destroy it. To meet this requirement, a dynamic voltage restorer (DVR) without dc-link energy storage elements is utilized to compensate any disturbance imposed to the DFIG wind turbine system. On the time of any disturbance or fault, DFIG and DVR are properly controlled in order to compensate the specified faulty phase uninterruptedly. DVR is connected in series to the grid and by injecting instantaneous compensating voltage, prevents the stator voltage from rapid changing; consequently, the rotor side converter can accomplish its normal operation. As voltage dips are the most common grid faults subjected to DFIGs, this paper investigates both symmetrical and asymmetrical voltage dips caused by grid faults. The independent and instantaneous phase voltage compensation, less volume, weight, and cost are the merits to utilize the proposed DVR along with DFIG wind turbines. PSCAD/EMTDC based simulations verifies the capabilities of the proposed technique for the LVRT capability of DFIG.
Anlysis of a pmsg based offshore wind farm fed to a onshore grid through hybr...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Design and Mitigation Techniques of MV Capacitor Bank Switching Transients on...ijtsrd
This paper presents the techniques to mitigate transients caused by capacitor switching in the distribution system. It includes the theory of capacitive switching transients with different methods of mitigation. The paper uses MATLAB SIMULINK software package to simulate the specific mitigation devices. The mathematical calculations of different parameters such as transient voltages, current, and frequencies for each device are compared with obtained value from the simulations of each case study. Poonam Bhati | Mukesh Kumar Lodha ""Design and Mitigation Techniques of MV- Capacitor Bank Switching Transients on 132 KV Substation"" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-4 , June 2019, URL: https://www.ijtsrd.com/papers/ijtsrd25093.pdf
Paper URL: https://www.ijtsrd.com/engineering/electrical-engineering/25093/design-and-mitigation-techniques-of-mv--capacitor-bank-switching-transients-on-132-kv-substation/poonam-bhati
The capability of low-voltage ride-through (LVRT) of doubly fed induction generator (DFIG) has been considered as an essence for grid code requirements. Any unbalance on the grid side causes the rotor current of the generator to rise which leads to saturate the dc-link of the back-to-back converter or even destroy it. To meet this requirement, a dynamic voltage restorer (DVR) without dc-link energy storage elements is utilized to compensate any disturbance imposed to the DFIG wind turbine system. On the time of any disturbance or fault, DFIG and DVR are properly controlled in order to compensate the specified faulty phase uninterruptedly. DVR is connected in series to the grid and by injecting instantaneous compensating voltage, prevents the stator voltage from rapid changing; consequently, the rotor side converter can accomplish its normal operation. As voltage dips are the most common grid faults subjected to DFIGs, this paper investigates both symmetrical and asymmetrical voltage dips caused by grid faults. The independent and instantaneous phase voltage compensation, less volume, weight, and cost are the merits to utilize the proposed DVR along with DFIG wind turbines. PSCAD/EMTDC based simulations verifies the capabilities of the proposed technique for the LVRT capability of DFIG.
Anlysis of a pmsg based offshore wind farm fed to a onshore grid through hybr...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Wide Area Oscillation Damping using Utility-Scale PV Power Plants Capabilities IJECEIAES
With increasing implementation of Wide Area Measurement Systems (WAMS) in power grids, application of wide area damping controllers (WADCs) to damp power system oscillations is of interest. On the other hand, it is well known that rapidly increasing integration of renewable energy sources into the grid can dangerously reduce the inertia of the system and degrade the stability of power systems. This paper aimed to design a novel WADC for a utility-scale PV solar farm to damp out inter area oscillations while the main focus of the work is to eliminate the impact of communication delays of wide-area signals from the WAMS. Moreover, the PV farm impact on inter area oscillation mitigation is investigated in various case studies, namely, with WADC on the active power control loop and with WADC on the reactive power control loop. The Quantum Particle Swarm Optimization (QPSO) technique is applied to normalize and optimize the parameters of WADC for inter-area oscillations damping and continuous compensation of time-varying latencies. The proposed method is prosperously applied in a 16-bus six-machine test system and various case studies are conducted to demonstrate the potential of the proposed structure.
Smart Power Transmission System Using FACTS DeviceIJAPEJOURNAL
Making of smart grids puts mounting pressure on the nation’s aging electric power transmission system. Just planting additional towers and stringing more line won’t practice the nation’s electric power transmission infrastructure to meet up the energy challenges ahead. Smart grids stand geared up to play a much larger role in the energy equation for reduction of transmission line losses. The FACTS controllers come out with the capability of enhancing transmission system control, reliability, and operation. This paper will discuss and express how Static Synchronous Compensator (STATCOM) has effectively been applied to power system for efficiently regulating system voltage and thus increase system load ability. This paper investigates the effects of (STATCOM) on voltage stability of a power system at different positions.The simulation analysis of this paper can be used as guideline for power industry. The study is thereby simulated using the MATLAB/SIMULINK software and simulation results show that STATCOM is effective in midpoint voltage regulation on transmission line. In this paper comparison is also performed between STATCOM and SVC under fault condition and it is proved that STATCOM have the capacity to provide more capacitive power for the period of a fault than SVC.
Power system solution provided by facts and hvdceSAT Journals
Abstract Various types of FACTS as well as HVDC have been available for some time. New ones have been developed recently. Their respective benefits are well proven and have been made known. System studies have to be done to make full use of FACTS and HVDC problem solving capabilities. This paper is described the technical and commercial benefits that FACT and HVDC solutions provided and case studies are presented showing how the relevant problem of power system can solved by this paper. Index Terms: FACTS, HVDC, POWER SYSTEM
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
In planning for Distributed Energy Resources (DER) in a microgrid, careful consideration must be taken to ensure the DER and microgrid are resilient during both grid-connected and islanded operation. There are many factors considered in the design of a microgrid, including the size of an existing DER, or the size of a new DER, the preferred DER/microgrid control technology and the material and labors costs. This paper discusses protection topics that need to be considered when analyzing microgrid voltage stability during fault conditions. Areas examined are fault contributions and voltage ride-though concerns with synchronous generators and inverter based DERs. A case study simulated on a real time power system simulator is presented in this paper.
Introduction
Across the developed world, renewable power generation is displacing conventional base load coal and nuclear generation. This often causes large shifts in power flow during both normal and emergency operation of the transmission system since wind and solar generation facilities are typically in different geographical locations from the plants they displace. As a result, certain existing High Voltage AC overhead transmission line circuits (usually shorter length lines below 400kV) may be required to handle much higher and rapidly changing normal and emergency, post-contingency power flows than allowed in the original line design.
Design of Earthing in Underground Substation using ETAP with ConstraintsYogeshIJTSRD
This paper describes the earthing design of a distribution substation 33kV 415V, 50Hz system. in this type of substation equipment’s are 33kV HV panel, transformer, battery, battery charger and Low voltage panels. The earth mat is below substation which is almost 15 18 Meter deep from ground level. The main considerable factors for earth mat design are soil resistivity which is higher due to basalt rock and system fault current. Fault current level of the system considered as 70kA derived from calculations. Earthing is essential for proper functioning of substation equipment’s and in the absence of proper designing affects in many ways like electric shock to personnel’s and malfunctions and damage to the equipment’s. The basic purpose of earthing is to ensure personnel safety, safe and reliable operation of equipment’s, prevent stray current, protection against interferences and keeps steps and touch potential within safe limit. This paper also discussed constraint in design due to below ground level. Result of manual calculation compared with design simulated through ETAP software version 19. The data used in design considered from a substation in Mumbai, Maharashtra. Daud Ahmad | Dr. Javed Ashraf "Design of Earthing in Underground Substation using ETAP with Constraints" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-5 , August 2021, URL: https://www.ijtsrd.com/papers/ijtsrd43787.pdf Paper URL: https://www.ijtsrd.com/engineering/electrical-engineering/43787/design-of-earthing-in-underground-substation-using-etap-with-constraints/daud-ahmad
These slides present the basics of different categories of energy storage devices, and their application to power system. Apart from that one control strategy has been presented. Later of the class I will discuss about its control strategies.
An adaptive protection scheme to prevent recloser-fuse miscoordination in dis...iosrjce
IOSR Journal of Electrical and Electronics Engineering(IOSR-JEEE) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of electrical and electronics engineering and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in electrical and electronics engineering. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
Wide Area Oscillation Damping using Utility-Scale PV Power Plants Capabilities IJECEIAES
With increasing implementation of Wide Area Measurement Systems (WAMS) in power grids, application of wide area damping controllers (WADCs) to damp power system oscillations is of interest. On the other hand, it is well known that rapidly increasing integration of renewable energy sources into the grid can dangerously reduce the inertia of the system and degrade the stability of power systems. This paper aimed to design a novel WADC for a utility-scale PV solar farm to damp out inter area oscillations while the main focus of the work is to eliminate the impact of communication delays of wide-area signals from the WAMS. Moreover, the PV farm impact on inter area oscillation mitigation is investigated in various case studies, namely, with WADC on the active power control loop and with WADC on the reactive power control loop. The Quantum Particle Swarm Optimization (QPSO) technique is applied to normalize and optimize the parameters of WADC for inter-area oscillations damping and continuous compensation of time-varying latencies. The proposed method is prosperously applied in a 16-bus six-machine test system and various case studies are conducted to demonstrate the potential of the proposed structure.
Smart Power Transmission System Using FACTS DeviceIJAPEJOURNAL
Making of smart grids puts mounting pressure on the nation’s aging electric power transmission system. Just planting additional towers and stringing more line won’t practice the nation’s electric power transmission infrastructure to meet up the energy challenges ahead. Smart grids stand geared up to play a much larger role in the energy equation for reduction of transmission line losses. The FACTS controllers come out with the capability of enhancing transmission system control, reliability, and operation. This paper will discuss and express how Static Synchronous Compensator (STATCOM) has effectively been applied to power system for efficiently regulating system voltage and thus increase system load ability. This paper investigates the effects of (STATCOM) on voltage stability of a power system at different positions.The simulation analysis of this paper can be used as guideline for power industry. The study is thereby simulated using the MATLAB/SIMULINK software and simulation results show that STATCOM is effective in midpoint voltage regulation on transmission line. In this paper comparison is also performed between STATCOM and SVC under fault condition and it is proved that STATCOM have the capacity to provide more capacitive power for the period of a fault than SVC.
Power system solution provided by facts and hvdceSAT Journals
Abstract Various types of FACTS as well as HVDC have been available for some time. New ones have been developed recently. Their respective benefits are well proven and have been made known. System studies have to be done to make full use of FACTS and HVDC problem solving capabilities. This paper is described the technical and commercial benefits that FACT and HVDC solutions provided and case studies are presented showing how the relevant problem of power system can solved by this paper. Index Terms: FACTS, HVDC, POWER SYSTEM
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
In planning for Distributed Energy Resources (DER) in a microgrid, careful consideration must be taken to ensure the DER and microgrid are resilient during both grid-connected and islanded operation. There are many factors considered in the design of a microgrid, including the size of an existing DER, or the size of a new DER, the preferred DER/microgrid control technology and the material and labors costs. This paper discusses protection topics that need to be considered when analyzing microgrid voltage stability during fault conditions. Areas examined are fault contributions and voltage ride-though concerns with synchronous generators and inverter based DERs. A case study simulated on a real time power system simulator is presented in this paper.
Introduction
Across the developed world, renewable power generation is displacing conventional base load coal and nuclear generation. This often causes large shifts in power flow during both normal and emergency operation of the transmission system since wind and solar generation facilities are typically in different geographical locations from the plants they displace. As a result, certain existing High Voltage AC overhead transmission line circuits (usually shorter length lines below 400kV) may be required to handle much higher and rapidly changing normal and emergency, post-contingency power flows than allowed in the original line design.
Design of Earthing in Underground Substation using ETAP with ConstraintsYogeshIJTSRD
This paper describes the earthing design of a distribution substation 33kV 415V, 50Hz system. in this type of substation equipment’s are 33kV HV panel, transformer, battery, battery charger and Low voltage panels. The earth mat is below substation which is almost 15 18 Meter deep from ground level. The main considerable factors for earth mat design are soil resistivity which is higher due to basalt rock and system fault current. Fault current level of the system considered as 70kA derived from calculations. Earthing is essential for proper functioning of substation equipment’s and in the absence of proper designing affects in many ways like electric shock to personnel’s and malfunctions and damage to the equipment’s. The basic purpose of earthing is to ensure personnel safety, safe and reliable operation of equipment’s, prevent stray current, protection against interferences and keeps steps and touch potential within safe limit. This paper also discussed constraint in design due to below ground level. Result of manual calculation compared with design simulated through ETAP software version 19. The data used in design considered from a substation in Mumbai, Maharashtra. Daud Ahmad | Dr. Javed Ashraf "Design of Earthing in Underground Substation using ETAP with Constraints" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-5 , August 2021, URL: https://www.ijtsrd.com/papers/ijtsrd43787.pdf Paper URL: https://www.ijtsrd.com/engineering/electrical-engineering/43787/design-of-earthing-in-underground-substation-using-etap-with-constraints/daud-ahmad
These slides present the basics of different categories of energy storage devices, and their application to power system. Apart from that one control strategy has been presented. Later of the class I will discuss about its control strategies.
An adaptive protection scheme to prevent recloser-fuse miscoordination in dis...iosrjce
IOSR Journal of Electrical and Electronics Engineering(IOSR-JEEE) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of electrical and electronics engineering and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in electrical and electronics engineering. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
Investigation of the challenges in establishing plug and play low voltage dc ...PromiseBeshel
A research proposal to improve the stability, efficiency, and reliability problems of low voltage DC microgrids from a communication control strategy point of view.
Analysis and Implementation of Power Quality Enhancement Techniques in Hybrid...ijtsrd
With the growth in global warming, renewable energy based distributed generators DGs play a prominent role in power generation. Wind, solar energy, biomass, mini hydro, and the usage of fuel cells and microturbines will provide substantial impetus in the near future. Environmental friendliness, expandability, and flexibility have made distributed generation, powered by a variety of renewable and unconventional energy sources, an appealing alternative for building contemporary electrical systems. A microgrid is made up of a group of loads and dispersed generators that work together to form a single controlled system. Microgrids, as an integrated energy delivery system, may function in tandem with or independently of the main power grid. The microgrid idea reduces the number of reverse conversions in a single AC or DC grid while also making it easier to link variable renewable AC and DC sources and loads to power systems. The connectivity of DGs to the utility grid through power electronic converters has raised concerns regarding equipment safety and protection. The microgrid may be configured to fulfil the customers specific needs, such as greater local dependability, reduced feeder losses, local voltage support, greater efficiency via waste heat usage, voltage sag correction, or uninterruptible power supply. The performance of a hybrid AC DC microgrid system in grid tethered mode is examined in this paper. For the creation of a microgrid, a solar system, a wind turbine generator, and a battery are utilized. Control methods are also included to allow the converters to appropriately coordinate the AC sub grid with the DC sub grid. The MATLAB SIMULINK environment was used to achieve the findings. Tarun Jaiswal | Ashish Bhargava "Analysis and Implementation of Power Quality Enhancement Techniques in Hybrid AC/DC Microgrid" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-5 , August 2021, URL: https://www.ijtsrd.com/papers/ijtsrd46296.pdf Paper URL: https://www.ijtsrd.com/engineering/electrical-engineering/46296/analysis-and-implementation-of-power-quality-enhancement-techniques-in-hybrid-acdc-microgrid/tarun-jaiswal
The paper highlights the need for an Active System Management (ASM) of distribution networks as a key tool for the efficient and secure integration of a high share of Distributed Energy Resources (DER). The paper provides technical and regulatory recommendations that mainly focus on distributed generation but are also largely applicable to flexible loads, electric vehicles and storage.
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Power Quality Enhancement Techniques in Hybrid AC DC Microgrid Analysis and I...ijtsrd
Distributed generators DGs that rely on renewable energy sources have become more important in the face of rising global temperatures. Substantial impetus will soon be supplied by wind, solar energy, biomass, mini hydro, and the use of fuel cells and microturbines. Distributed generation, where electricity is produced by a number of different renewable and unconventional energy sources, has emerged as a viable option for the construction of modern electrical systems because to its low environmental impact, scalability, and adaptability. A microgrid is a small scale electrical grid in which multiple loads and distributed generators are coordinated under a single set of controls. Microgrids are a kind of integrated energy delivery system that may either work in tandem with the main power grid or operate autonomously. The concept of a microgrid eliminates the need for several inverters in a single AC or DC grid and simplifies the connection of intermittent, renewable AC and DC power sources and loads. Equipment safety and security issues have been brought to light by the power electronic converters that link DGs to the utility grid. Greater local dependability, lower feeder losses, local voltage support, increased efficiency through waste heat use, voltage sag correction, and uninterruptible power supply are only some of the configuration options available to the client for the microgrid. In this study, we analyse the functionality of a hybrid AC DC microgrid while connected to the mains power supply. A solar array, a wind generator, and a battery are used to build a microgrid. The converters can now properly coordinate the AC and DC sub grids thanks to the added control techniques. Results were obtained by use of the MATLAB SIMULINK software environment. Sumit Kumar | Ashish Bhargava "Power Quality Enhancement Techniques in Hybrid AC/DC Microgrid Analysis and Implementation" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-6 | Issue-6 , October 2022, URL: https://www.ijtsrd.com/papers/ijtsrd52196.pdf Paper URL: https://www.ijtsrd.com/engineering/electrical-engineering/52196/power-quality-enhancement-techniques-in-hybrid-acdc-microgrid-analysis-and-implementation/sumit-kumar
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Dealing With Reactive Power in Islanded Micro Grid Corresponding Power Distri...ijtsrd
A Micro grid MG is a local energy system consisting of a number of energy sources e.g., wind turbine or solar panels among others , energy storage units, and loads that operate connected to the main electrical grid or autonomously. MGs provide flexibility, reduce the main electricity grid dependence, and contribute to changing large centralized production paradigm to local and distributed generation. However, such energy systems require complex management, advanced control, and optimization. Moreover, the power electronics converters have to be used to correct energy conversion and be interconnected through a common control structure is necessary. A classical droop control system is often implemented in MG. It allows correct operation of parallel voltage sourced converters in grid connection, as well as islanded mode of operation. However, it requires complex power management algorithms, especially in islanded MGs, which balance the system and improves reliability. The novel reactive power sharing algorithm is developed, which takes into account the parameters of the converter as apparent power limit and maximum active power. The developed solution is verified in simulation and compared with other known reactive power control methods. G. Amulya | Dr. S. V. D. Anil Kumar "Dealing With Reactive Power in Islanded Micro Grid-Corresponding Power Distribution in Hierarchical Droop Control using Photovoltaic System" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-5 , August 2019, URL: https://www.ijtsrd.com/papers/ijtsrd26498.pdfPaper URL: https://www.ijtsrd.com/engineering/electrical-engineering/26498/dealing-with-reactive-power-in-islanded-micro-grid-corresponding-power-distribution-in-hierarchical-droop-control-using-photovoltaic-system/g-amulya
Внедрение распределенной энергетики в систему централизованного энергоснабжения: Проблемы и решения. Докладчик: Ларри Адамс, Дания (Spirae Inc, Главный инженер по электронике). Семинар "Распределённая генерация: технические аспекты", 13 февраля 2013 г.
Similar to Dynamic line rating as a means to enhance transmission grid resilience (20)
Multi-Conductor Distribution Rollers
The No. 5403 Multi-Conductor Distribution Roller is constructed from light weight, high strength 356-T6 aluminum alloy and may be ordered with any of the following accessories.
A - No. 5403 Roller.
B - No. 5413 Hook Assembly.
C - No. 5423 Cross Arm Bracket.
D - No. 5433 Suspension Yoke.
E - No. 5443 Up-Lift Roller.
G - No. 5463 Running Board.
Running Boards are designed for the Lindsey Multi Conductor Distribution Rollers to assure each conductor and pulling line is deposited in the proper sheave groove. Running boards are proof tested at the factory prior to shipment. Swivels may be ordered factory installed. Safe working load is 2,500 pounds. All ferrous materials are hot dip galvanized or electro cadmium plated. Sheaves are mounted on precision ground Conrad type, permanently lubricated and sealed, maintenance-free ball bearings. Weight as shown: 25 pounds.
The No. 5333 was designed specially for stringing up to 3-inch wide flat conductor. A unique pivoting feature allows the sheave and springloaded keeper to follow the conductor through a 180º arc. http://lindsey-usa.com/hardware/stringing-equipment/ Supplied with a 48 inch chain and hook for pole mounting, the No. 5333 can also be suspension mounted without removing the pole bracket or chain. The sheave has a 2 1/2" I.D., 6" O.D. and is mounted on oil impregnated bushings for a long, maintenance-free operating life. Parts are lightweight 356-T6 aluminum alloy with a ductile iron pole bracket and steel chain. Weight is 11 lbs.
This unique stringing tool enables one lineman to quickly transfer the conductor from the roller to the clamp with one hand, without removing the roller or lifting the conductor. The No. 5326 can be used on horizontal insulators or, with adapters on vertical insulators and cross arms.
One of the most critical aspect of emergency restoration
is effective communication between all of the parties
involved. One of the most important pieces of
equipment is communications equipment. The foremen
and supervisors have been equipped with new satellite
phones to improve communication between field and
TC&M headquarters where most of the materials and
equipment are kept. The satellite phones take care of
dead spots in LADWP’s service territory that normal
cell phones and low band radio are unable to serve.
The Transmission Construction and Maintenance
Organization (TC&M) reports to the Director of the
Bulk Power Business Unit who in turn reports to the
power system Assistant General Manager of the Los
Angeles Department of Water and Power. The TC&M
Organization is responsible for all maintenance, capital
improvement jobs and emergency response when there
is a transmission line failure
LADWP provides electricity to approximately 1.4
million electrical customers in a 1202-square-km area.
Business and industry consume about 70 percent of the
electricity in Los Angeles, but residences constitute the
largest number of customers. In addition to serving these
consumers, LADWP lights public streets and highways,
powers the city's water system and sells wholesale
electricity to other utilities.
LADWP supplies power from many sources, including its
own hydroelectric and fossil-fueled generating stations
and contracts for hydroelectric power from the Pacific
Northwest. Coal is the largest single source of power
supply in Los Angeles at 45 percent. Natural gas now
supplies about 20 percent of the city's energy;
hydroelectricity accounts for 12 percent; nuclear, 9
percent, and the remainder comes from purchased power,
including biomass, solar and cogeneration. LADWP has
a net dependable capacity of approximately 7000MW,
and an annual peak demand of approximately 6000MW.
To prepare a technical feasibility proposal http://lindsey-usa.com/wp-content/uploads/2015/10/LINDSEY-ERS-Questionnaire-100812.pdf
for the Lindsey Emergency Restoration System (ERS). The information
requested in this questionnaire is the minimum required for assembling a
proposal. A worksheet should be prepared for each voltage level as well as for
each critical line. Any additional information or expansion on any item would be
beneficial.
The Lindsey Fail‐Safe Base improves the integrity of horizontal line post construction by providing a flexible support for the insulator. This flexibility lowers the dynamic stresses induced in an insulator by an impact load. In addition to this elastic flexibility, Fail‐ Safe Bases are designed to plastically deform at a predetermined level, thus limiting the maximum cantilever load that can be applied to the insulator. These features protect the insulator not only from longitudinal overloads but also from vertical overloading, e.g. from severe ice conditions. Extensive static and dynamic tests have been performed on Fail‐Safe Bases. These dynamic impact tests demonstrate that insulators, when mounted on a Fail‐Safe Base, would not break when subjected to four or five times the maximum impact load of a rigidly mounted insulator.
The increased use of clamp top insulators has required a need for dead ending. Lindsey's new Dead End Adapters fit most standard Clamp Top Insulators. Lindsey Dead End Adapters are designed for use with both horizontal and vertical clamp top line post insulators. the No. 2130 allows dead ending in both directions from a single insulator. Lindsey Dead End Adapters are designed for dead ending with vertical clamp top line post insulator in a horizontal position. Lindsey Dead End Adapters are designed for use with both horizontal and vertical clamp top line post insulators. as well insulator installed in a horizontal position.
Lindsey’s Pole Top Bracket securely mounts to a pole top for installation of vertical insulator directly above the center of the pole for more uniform appearance installation to the pole is accomplished with two bolts (not furnished with brackets) witch pass through the pole and side plates and are secured with nuts at both ends. Hole sizes in the side plates are 13/16”. Brackets are adjustable to fit poles from 71/2 to 16”. The top plate has a 5” bolt circle, with 11/16” holes, and center bolt hole 15/16” for insulator mounting. The Lindsey No. 8234 Drilling Jig shown in Section 8 is ideally suited for drilling mounting holes in the pole. The photo shows a typical triangular construction using the No. 2050 Pole Top Bracket and a Lindsey Horizontal Fail Safe Extension Arm with shroud.
http://lindsey-usa.com/hardware/pole-line-hardware-insulating-bases/
Convert Tie-Top Insulators to Clamps-Top
Lindsey UNICON conductor clamps convert tie-top insulators to clamps-top. The result has
all the safety advantages inherent in the clamp-top, plus economy. On new construction
the cost off tie-top insulators plus UNICON is comparable to clamp/top.
UNICON clamps can be installed with a standard wrench or hot stick without removing
parts. This eliminates long, hazardous tie wires and makes maintenance on hot lines safer
and faster. These clamps are used to increase the capacity of a primary voltage system by
increasing the conductor size and re-using the installed insulator and construction wherever
possible.
UNICON clamps combine an adjustable insulator clamp with a unique single-bolt reversible
keeper which makes it possible to fit a wide range of insulator and conductor sizes with
minimum inventory. Radio interference and the cost of future reconductoring and/or armor
rodding is also reduced. Years of development testing and trouble-free field service of more
than a half million UNICON clamps attest to their safety, reliability and economy.
Events that may test transmission grid resilience are varied. Some involve minimal
permanent damage and can be recovered from relatively quickly. Other events may require
much longer periods of time to recover where extensive damage has occurred. Some events
are fast to develop, while other may provide an opportunity to prepare (weather) or not
(willful attack).
Resiliency consists of both the ability to resist failure and to rapidly recover from failure.
Both sides of grid resiliency as it applies to the transmission grid can possibly be addressed by
dynamic line rating (DLR). The purpose of this paper is to present for discussion the use of
DLR as a means to improve grid resiliency in a way that is cost effective, quick to deploy, and
which provides ongoing operational benefits when not being used for resiliency purposes.
For events involving longer term outages associated with major transmission line fall downs,
multiple line outages, or critical substation outages, DLR offers a number of possible
advantages. Widespread preemptive installation of DLR can address the problem of
determining long term line overload ratings that are necessary when facing the sudden yet
long term absence of major assets. DLR can alleviate congestion and other constraints that
may appear during recovery. Finally, DLR can provide the added capacity that may be
required by lower voltage lines in such events but which would otherwise be difficult to
justify economically for normal operation.
Specially designed for tie top insulators, This type clamp features a long steel stud for
mounting on a variety of different diameter insulators. Nuts are captive at both ends for
ease off installation. A single bolt clamping feature makes conductor installation possible
with a standard wrench or hot stick without removing parts. Only three clamp sizes are
required for conductor diameters from .25 to 1.5 inches. No parts need be removed for
assembly to insulators or clipping in conductor. All cast parts are high strength heat treated
356-T6 aluminum alloy. Steel parts are hot dip galvanized for maximum corrosion
resistance. This series is also available in all-aluminum clamp having a cast 356-T6 high
strength heat treated aluminum body, keeper, and clamp with aluminum alloy stud, nuts,
and lockwashers. To order all-aluminum clamp specify catalog number using suffix AA. For
correct clamp size to use with a given conductor, and neck sizes of pin and post type
insulators, refer to tables in the engineering Data Section of this catalog.
Maintaining proper transmission line clearance is required by the North American Electric Reliability
Corporation (NERC). Locations where two lines cross or are co-located along a common right-of-way
pose a difficult monitoring challenge: determining the clearance between the crossing lines. While the
National Electric Safety Code details what these clearances should be and how they should be
estimated based on a variety of criteria, these calculations do not provide confirmation of actual
clearance or of the clearance itself. This becomes particularly important when the loading
characteristics of the crossing lines vary significantly, or if future system changes may result in
unpredictable clearances. In this case the sag characteristics of each line cannot be assumed to result in
a consistent clearance value, as each line may be loaded differently as they are often on different
circuits. The spatial difference of the lines can also result in different wind levels and a difference in
the rate of cooling of the conductors.
Resiliency consists of both the ability to resist failure and to rapidly recover from failure.
Both sides of grid resiliency as it applies to the transmission grid can possibly be addressed by
dynamic line rating (DLR). The purpose of this paper is to present for discussion the use of
DLR as a means to improve grid resiliency in a way that is cost effective, quick to deploy, and
which provides ongoing operational benefits when not being used for resiliency purposes.
Resiliency consists of both the ability to resist failure and to rapidly recover from failure.
Both sides of grid resiliency as it applies to the transmission grid can possibly be addressed by
dynamic line rating (DLR). The purpose of this paper is to present for discussion the use of
DLR as a means to improve grid resiliency in a way that is cost effective, quick to deploy, and
which provides ongoing operational benefits when not being used for resiliency purposes.
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Dynamic line rating as a means to enhance transmission grid resilience
1. jmccall@lindsey-usa.com
Dynamic Line Rating as a Means to Enhance Transmission Grid Resilience
J. C. McCall T. Goodwin
Lindsey Manufacturing Tip Goodwin Consulting LLC
USA USA
SUMMARY
Events that may test transmission grid resilience are varied. Some involve minimal
permanent damage and can be recovered from relatively quickly. Other events may require
much longer periods of time to recover where extensive damage has occurred. Some events
are fast to develop, while other may provide an opportunity to prepare (weather) or not
(willful attack).
Resiliency consists of both the ability to resist failure and to rapidly recover from failure.
Both sides of grid resiliency as it applies to the transmission grid can possibly be addressed by
dynamic line rating (DLR). The purpose of this paper is to present for discussion the use of
DLR as a means to improve grid resiliency in a way that is cost effective, quick to deploy, and
which provides ongoing operational benefits when not being used for resiliency purposes.
For events involving longer term outages associated with major transmission line fall downs,
multiple line outages, or critical substation outages, DLR offers a number of possible
advantages. Widespread preemptive installation of DLR can address the problem of
determining long term line overload ratings that are necessary when facing the sudden yet
long term absence of major assets. DLR can alleviate congestion and other constraints that
may appear during recovery. Finally, DLR can provide the added capacity that may be
required by lower voltage lines in such events but which would otherwise be difficult to
justify economically for normal operation.
Cascading failure events involve the sequential tripping of a number of transmission lines as
they become overloaded after a precipitating event. DLR offers the potential to act as a line
capacity buffer of sorts to reduce or prevent cascade line tripping.
As a grid resilience technology solution DLR also provides many economic benefits during
normal grid operations. This is compared to “insurance policy” type of expenditures that are
difficult, or less satisfying, to justify.
KEYWORDS
Dynamic line rating, DLR, resilience, cascading outages, grid collapse
21, rue d’Artois, F-75008 PARIS CIGRE US National Committee
http : //www.cigre.org 2015 Grid of the Future Symposium
Lindsey Publication Number 11T-002 DLR RESILIENCE • October 2015
2. 2
INTRODUCTION
Grid resiliency is defined as the ability to resist failure and rapidly recover from breakdown.
There are any number of causes of power system events that can result in loss in the ability to
supply power to loads. A few causes relevant to the topic of this paper are:
Cascaded transmission line trips resulting in blackouts
Weather related events that may damage or destroy one or more transmission lines or
even entire substations
Willful attacks on critical transmission lines or substations
Some of these events are fast to develop and may provide an opportunity to prepare (weather)
or not (willful attack). Some events involve minimal permanent damage and can be
recovered from relatively quickly (blackouts caused mainly from line tripping). Other events
may require much longer periods of time to recover where extensive damage has occurred.
Looking at each of these scenarios from the resiliency definition of “resisting failure” and
“rapidly recovering” produces many perspectives for examination. But for these scenarios,
both sides of resiliency can also be uniquely addressed by dynamic line rating. The purpose of
this paper is to present for discussion the benefits that an existing yet widespread deployment
of dynamic line rating would provide as a means to improve grid resiliency in a way that is
very cost effective, and which provides ongoing operational benefits when not being used for
grid resiliency purposes.
DYNAMIC LINE RATING
Every transmission line has a static rating; effectively a nameplate power rating. Static
transmission line rating methodologies are dependent on several environmental variables
identified in IEEE standard 738 and CIGRE brochures 207 and 324. These variables are
related to the amount of heat generated in the line (resistance and current), heat being added to
the line (solar radiation), and heat being removed from the line (convective and radiated
cooling). The common practice for transmission line rating is to select conservative values for
these environmental variables which may be fixed or seasonally varied, and that equate to a
low probability that conductor sag will exceed operational or regulatory limits for a very short
duration. This methodology directly acknowledges that operational limits of transmission
lines are conservative most of the time.
The concept behind dynamic line rating (DLR) is that if the actual real-time status and
behavior of the transmission line is known, then it is possible to determine a real-time line
capacity, rather than depending upon a capacity based on a set of conservative, fixed,
assumptions. This is satisfyingly intuitive as many of the factors that DLR accommodates
(ambient temperature, solar radiation, wind, rain, etc.) vary almost continuously. Wind is
particular as it is not only transient, but its impact on line cooling is multivariate, with
velocity, orientation and spatial context playing roles. This is an important concept as per the
US Department of Energy, DLR techniques have been shown to increase a line’s static rating
by as much as 100%. [1] In all fairness, it must also be noted that it is possible for DLR to
occasional reduce a line’s rating to below its static rating when conditions are right, for
example, when wind speed drops below that normally used for static ratings (0.6m/sec). [2]
In practical application, taking advantage of DLR capacity increases greater than ~25% above
static may not be possible unless other potentially limiting line components are also upgraded.
This could include items such as switches, CTs and PTs, wave traps, and possible even circuit
breakers. Taking advantage of higher levels of DLR capacity may also require examination
Lindsey Publication Number 11T-002 DLR RESILIENCE • October 2015
3. 3
of relay settings so as not to expose the grid to mis-operations. [3] However, if the cost
involved in upgrading the next limiting device or devices is determined, then the economic
benefit of releasing this extra capacity through DLR is easily determined. [4]
DLR makes use of technologies that allow for the real-time measurement and monitoring of
the critical parameters of a transmission line. Specifically, conductor clearance-to-ground (or
its cousin, sag), conductor temperature and current. Add to this weather information such as
wind speed, ambient temperature, etc., and the ability to communicate all of this information,
and computer models can then be used to determine both real-time, and even forecasted line
capacity ratings. Note that spot readings of conductor temperatures must be tempered and
cannot be depended upon directly. For example, the author’s company’s DLR software learns
overtime how the spot temperatures correlate to the average conductor temperatures used in
IEEE standard 738 and CIGRE brochures 207 and 324.
Numerous papers have been written detailing the benefits of DLR to a utility. Some of the
more commonly cited benefits include [5]:
Relieving congestion and transmission related constraints
Increased transmission capacity at minimal investment
Real time monitoring of thermal state of conductors
Increased situational awareness for operators
Improved forecasting
Deferment of large capital investments
Enhanced performance of reliability of aging assets
More efficient integration of renewables such as wind and solar energy
Potential savings with generation dispatch
This paper will focus on the first five of these listed benefits and their impact on grid
resilience.
It should be noted that dynamic line rating systems are very quick to deploy compared to
other means of adding incremental line capacity (re-conductoring, constructing parallel
circuits, etc.). The assumption is also that the dynamic line rating systems will have been
deployed before any system resiliency event occurs.
MAJOR ASSET LOSS MAY REQUIRE
LONG TERM RATING INCREASES
Individual transmission towers are regularly
damaged by weather or willful events and
result in the affected transmission line being
removed from service until the tower can be
repaired or replaced. Some events result in the
collapse of dozens of towers. See Figure 1.
One infamous event was the 1998 ice storm in
Canada where 300 towers in Quebec and
another 50 in Ontario collapsed due to ice
loading [6]. Substations are not immune to
weather either as witnessed by the loss in 2014
of an entire 500kV substation in Arkansas due
to a direct hit by a tornado. [7]
Figure 1: One of 16 cascaded 500kV DC Towers collapsed at
the Los Angeles Department of Water and Power (LADWP) in
1988 due to High Winds
Lindsey Publication Number 11T-002 DLR RESILIENCE • October 2015
4. 4
The ability to implement any “rapid recovery” type of resilience is gated by the ability to
access spare equipment, emergency stores, crews, and the resulting rebuild time. During this
time, the grid should be able to resiliently adapt to supply power in the absence of these lines
or stations.
Possible Line Capacity Issues
Should one or more substations or transmission lines be lost to natural or man-made
calamities, a resilient grid must be able to provide alternate transmission paths around the
damaged portion of the grid to ensure power can serve the affected load. This ability is
dependent on the capacity of those transmission lines still in service. One concern is that such
outages are relatively long-term, where no “emergency rating” equivalent for transmission
lines can be used to address any path capacity limitations.
Normal sources of generation used to serve loads may no longer be cost effective from an
economic dispatch perspective if the normal transmission paths are sufficiently disrupted.
Here, generation mixes that do not exceed allowable ratings may not be possible [8].
Conversely, remaining transmission paths may become so constrained or congested that it
may be not be possible to supply power effectively.
While the long term outage of a single 69 – 230kV line may not be cause for too much
concern from a resiliency standpoint, the collapse of a major EHV line at 345kV – 765kV, or
an HVDC line, or attacks on one or two critical EHV substations likely would be. In these
events the lower voltage transmission assets will more likely be depended upon to absorb the
additional transmission capacity. Lower voltage lines are more commonly on the cusp when it
comes to capital investment upgrade capacity for constraint or contingency events as these
investments are much harder to justify economically.
Alleviating line capacity issues with DLR
An existing DLR deployment could be an effective tool to address all of these identified
issues.
DLR can provide both real-time and forecast short- and medium-term “emergency-
equivalent” ratings for all remaining in service lines.
Varying amounts and types of generation offered to the grid, economic dispatch
issues, the dynamic topology of a grid during a recovery event, and so forth, all
present challenges to operation personnel. DLR can provide a window into an equally
dynamic and flexible transmission network where constraints would be more easily
mitigated.
As mentioned, uprating lower voltage lines for marginal contingency scenarios is
often difficult to justify economically. Yet in the event of a major outage as described
here, this additional capacity may become instantly desired. DLR is a very cost
effective means to address line capacity upgrades where the economic case, normally
hinging on a 5 - 10% increase in capacity for normal N-1 scenarios, is difficult to
make [9]. This can be true at higher voltages, where N-2 or greater scenarios may need
be considered. Again, it must be noted that there is a risk additional line capacity may
not be available due to certain weather conditions. In such event, grid operations may
need adjust dispatch and experience some congestion costs to maintain reliability
requirements.
Lindsey Publication Number 11T-002 DLR RESILIENCE • October 2015
5. 5
Line reconductoring is a common solution to upgrading lines. This cost can range
from $1 million to $8 million per mile or more depending on voltage class [10]. An
example clarifies this. An 80km (50 mile) line could cost $50 million to $400 million
to reconductor. Depending upon the installation requirements and the DLR system
selected, the cost for a DLR implementation would typically range well under $0.5
million, regardless of voltage. DLR can redefine the economics of even marginal line
upgrade decisions.
CASCADING OUTAGES
Loss of transmission paths have been the cause of most major blackouts in North America
over the past 50 years as losing these paths limit the amount of power generation that can be
successfully moved to load centers. Tripping lines when they exceed their operating limits is
common to cascading outages and can “potentially widen cascade failures.” [11].
In cascading failures, one precipitating event leads to another, and so forth, until an entire
system, or a large part of it, collapses. This is true of any type of system, with power systems
being but one example of this. The failure event can be the failure of a network node (i.e.,
substation and/or generation station) or a network connection (transmission line). When a
cascade of transmission line trips begins to occur, the network loses its ability to carry the
required power flows and the network becomes vulnerable [12]. The common scenario is for
one line to trip, rerouting power to another line, causing a real or protective overload,
resulting in a second line trip, and so forth. Research shows that the more complex and tightly
interconnected the network the more fragile it is, and therefore more likely to suddenly
collapse due to cascading events [11]. As power grids are becoming increasingly more
meshed to increase their flexibility and reliability, this increases the importance of arresting
the possibility of cascading events.
Further, studies have shown that attacks on a small number of nodes (substations) can
precipitate cascading line failures. While some military analyses have focused on defending
the nodes [13], an alternate solution may be in preventing the node attacks from causing the
lines to be overloaded and trip.
DLR as a possible means to limit Cascading Outages
When a line trips from some precipitating event, increased burdens are suddenly placed on the
remaining lines in the transmission network. While there may be other reasons to trip further
lines, for example grid stability issues, subsequent line trips resulting from overloads may
possibly be minimized by an existing DLR system where the true capacity of the line is
available in real-time. Preventing cascade tripping can increase the likelihood that even a
tightly interconnected system will not experience a sudden collapse.
Effectively integrating DLR into grid operations during a cascading event will not be trivial as
it may likely involve interaction with relay settings. For example, unnecessary line tripping
occurred during the August 14, 2003 blackout in the U.S. and Canada due to operation of
zone-3 distance relays set to prohibit lines from exceeding their static emergency overload
ratings. [14] While DLR by itself would not have avoided that, it does identify one example
as to how interaction between DLR and relays could be beneficial. In this case, zone-3
settings could be adjusted based on a line’s computed DLR. This may be possible
considering the highly programmable nature of modern protective relays, in conjunction with
high speed inter-relay communications made possible with communication protocols such as
IEC 61850.
Lindsey Publication Number 11T-002 DLR RESILIENCE • October 2015
6. 6
Here the “resisting failure” aspect of grid resiliency would come into play. DLR eliminates
the grid as a set of fixed capacity transmission assets, and replaces it with a living set of
transmission pathways whose capacities reflect real-time conditions and the capabilities,
above or below static ratings, of those lines. The ability to absorb sudden increases in load
without resorting to defensive protective relay based trips could be critical to limiting cascade
events. The increased flow capacity and ability to bypass damaged line reduces the risk of
cascading failures [15]. Line capacities can act more as elastic bands than taught strings and
the grid may become more resilient.
DLR AS AN ECONOMICALLY POSITIVE RESILIENCE SOLUTION
Utilities spend billions of Dollars on improving grid resilience. Many of these costs are
defensive in nature; walls, fences, video cameras, spare equipment, redundant systems, etc. A
spare transformer is simply a frozen financial asset unless it is someday needed.
Conversely, DLR offers every day economic benefits to a utility that quickly pay for any DLR
investments. These benefits include [16]:
Reduction or elimination of congestion expenses
Provides the least cost solution for moderate capacity increase projects
Delivers additional revenue by utilizing the line’s full, real-time, capacity
Provides a cost effective line clearance compliance tool
Provides least cost solution to accommodate gradually increasing loads
Eliminate expensive conductor damage from line overheating
Improves N-1 Modeling
The resilience aspects of DLR in both allowing the grid to deal with long term major facility
outages, and in potentially ameliorating cascading outages, are substantial additional benefits
of DLR.
CONCLUSIONS
Dynamic line rating (DLR) is a technology that offers utilities many economic benefits under
normal operations. However, DLR may also provide strong grid resilience benefits. During
long term substation or transmission line outage scenarios DLR may enhance recovery. DLR
may possibly also be part of a system to limit or prevent cascade line outages and the
potential system collapse such scenarios present.
BIBLIOGRAPHY
[1] “Dynamic Line Rating Systems for Transmission Lines: Topical Report,” Smart Grid
Demonstration Program, US DOE, April 25, 2014, page vi
[2] ibid, p. 6
[3] DYNAMIC LINE RATING Oncor Electric Delivery Smart Grid Program Final
Report, Oncor Electric Delivery Company, August 1, 2013, p190
[4] ibid, p. F-12.
[5] “Dynamic Line Rating Benefits, Methodology & Challenges,” A Kapur, Consolidated
Edison Company, GridWeek 2012 Conference, Washington, DC, October 2012
[6] “Quebec ice storm: Why it's impossible to storm-proof the power grid,” Andre Mayer,
CBC News, Jan 05, 2015, posted on-line at
http://www.cbc.ca/news/technology/quebec-ice-storm-why-it-s-impossible-to-storm-
proof-the-power-grid-1.2890371
Lindsey Publication Number 11T-002 DLR RESILIENCE • October 2015
7. 7
[7] “EF4 Tornado Ravages; Entergy Arkansas Rebuilds,” Transmission and Distribution
World Magazine, May 14, 2014
[8] ibid 3, p. 6.
[9] ibid 3, pp. 44 and 121.
[10] “2012 Final PG&E Generator Interconnection Unit Cost Guide” spreadsheet, Pacific
Gas & Electric Co., January 30, 2012, downloaded at
https://www.caiso.com/Documents/PGE_2012FinalPerUnitCostGuide.xls
[11] Pahwa, S., Scoglio, C. & Scala, A. Abruptness of Cascade Failures in Power Grids.
Sci. Rep. 4, 3694; DOI:10.1038/srep03694 (2014).
[12] “Vulnerability Assessment for Cascading Failures in Electric Power Systems”, Task
Force on Understanding, Prediction, Mitigation and Restoration of Cascading Failures,
IEEE PES Computer and Analytical Methods Subcommittee, IEEE Power and Energy
Society Power Systems Conference and Exposition 2009, Seattle, WA
[13] Shakarian, P., Hansheng, L., Lindelauf, R., “Power Grid Defense Against Malicious
Cascading Failure,” AAMAS '14 Proceedings of the 2014 international conference on
Autonomous agents and multi-agent systems, January 6, 2014
[14] “Final Report on the August 14, 2003 Blackout in the United States and Canada:
Causes and Recommendations”, U.S.-Canada Power System Outage Task Force, April
2004, p204
[15] “ECONOMIC BENEFITS OF INCREASING ELECTRIC GRID RESILIENCE TO
WEATHER OUTAGES,” Executive Office of the President, August 2013.
[16] ibid 3, p. 8.
Lindsey Publication Number 11T-002 DLR RESILIENCE • October 2015