Novel methods for assessing the protection impacts of. Improvement of protection coordination for a distribution system. A case study comparison of california and new york proceedings 5 solar customers. Us9053020b2 online protection coordination for distribution. Impact of distributed generation on distribution system and its protection. The methodology takes into account typical protection schemes, normative, general protection requirements, protections coordination and distributed generation impact to protection system, and its applicable to planning systems or for existing systems initially without dg. Impact of distributed generation on distribution systems and.
Pdf protection coordination planning with distributed. Ground fault current on low voltage systems may be. Optimal distributed generation planning in radial distribution. Protection coordination in distribution systems with and. In the available literature, the protection coordination schemes for radial distribution systems and developments in the area of protection coordination are discussed in detail. Protection system considerations in networks with distributed. Issues like voltage regulation, flicker, harmonics and loss of coordination between circuit breaker and fuse need to be addressed for integration of dg into dn.
This paper presents a study on protection coordination of over current relays ocrs in a distributed system by considering its different operating modes. The flexible operation of microgrids, along with the availability of distributed generation dg units, causes a variety of changes in shortcircuit current levels, magnitudes, and directions, which has undesirable effects on the operation of protection systems. The main purpose of this report is to serve as a guideline for assessing the impact of distributed generation dg on the protection coordination of the distribution network. Jul 21, 2017 in the available literature, the protection coordination schemes for radial distribution systems and developments in the area of protection coordination are discussed in detail. Protection coordination for a distribution system in the. Abdelgalil and others published protection coordination planning with distributed generation find, read and cite all the research you need on researchgate. Conventional protection schemes use typical directional overcurrent relays docrs with limited operating capability, unable to. Archived protection coordination planning with distributed generation information archived on the web information identified as archived on the web is for reference, research or recordkeeping purposes. Implementing nerc guidelines for coordinating generator and. Developments in the assessment of dg from a strategic. Achieving relay coordination and selective short circuit.
In the integrated distributed planning concept, utilities or distribution system operators proactively study the hosting capacity of distribution circuits, the ability of these distribution circuits to accommodate growth in distributed generation, and any necessary infrastructure upgrades, all in advance of receiving interconnection requests. Introduction recent misoperations of generation protection during major system disturbances have highlighted the need for. The course discusses the effect of load and distributed generation sources on protection. Electrical power systems must be designed to serve a variety of loads safely and reliably. Protection coordination with distributed generation in electrical system of iraqi distribution grid. Planning and coordination of relay in distribution system using etap article pdf available in pakistan journal of biotechnology special.
With this distributed generation dg in distribution systems, its function generally tends to be changed. This paper proposes a new backup protection scheme, named coordinated backup protection cbp scheme, for distribution networks containing distributed generation. However, it is very important to know the margin required for the preservation of the. A multiplestage protection is often required to meet with the sensitivity and operating speed requirements and to achieve a good and reliable grading of the protection, see figure 1. Distributed generation dg, energy, selectivity, sensitivity, reliability, protection schemes, active distribution networks 1. Also possible fault current infeed from the distribution network side due to distributed generation, for. Distributed generation dg has been widely used in distribution network to reduce the energy losses, improve voltage profile and system reliability, etc. Talaata a faculty of engineering, ain shams university, egypt b abb, egypt received october 2015. Among these issues, protection coordination is a major concern as it directly affects continuity of service and reliability of service. Coordination of overcurrent relay in distributed system. Mozina, beckwith electric company, 6190118th avenue north, largo, fl 33773 i. One way to reduce the effects of distributed generation protection system of distribution systems is re coordination of protective devices. This manual on electric power distribution systems is one of a series developed to aid utility supervisory personnel at shore establishments in the performance of their duties. The increasing amount of distributed generation dg in distribution networks dns is giving rise to power quality and protection coordination problems.
The additional power delivered by dg significantly affects the bus voltage, load characteristics and reliability of the system 5. Distributed generation dg protection overview abstract one of the biggest changes happening to the distribution system is the introduction of distributed generation. These effects leads to effects on distribution systems protection. Solutions to design and coordination relays for protection. Effect of distributed generation on protective device. Protection considerations for distributed generation presented by scott r. A case study comparison of california and new york proceedings 5. In this paper, a novel model for dg planning is proposed to. Protection measures system voltage at the point of common coupling. Provide planning engineers with insight into how power plant and. Pdf distributed generator and their effects on distribution system. In particular, the report details and presents a generalized assessment procedure for determining the impact of the integration of dg on the protection practices of distribution systems. It includes information obtained from extensive research of current literature on the subject. Expert system for protection coordination of distribution.
One of the drivers behind this movement is the need to integrate renewable energy sources into the distribution system. The recommendations in the white paper are not yet a nerc standard, but will provide the. Implementing nerc guidelines for coordinating generator. However, it is very important to know the margin required for the preservation of the protection coordination when a distributed. Distributed generation dg protection overview western. Austria one potential impact of interconnecting distributed generation dg is the potential sympathetic tripping of overcurrent oc protection devices, where a healthy feeder trips unnecessarily for a fault on another feeder. A new coordinated backup protection scheme for distribution. Introduction distributed generation dg technology is gaining in popularity due to the ever increasing demand for energy, the depletion of fossil fuel resources and a greater emphasis on clean energy. Upon integration of the distributed generation with a distribution system, the con guration for power ow for a conventional network is changed from a unidirectional to multidirectional system. Impact of distributed generation on distribution systems and its. The optimal size and location of incoming distributed generation are preliminary. Protection coordination planning with distributed generation, t. Archived protection coordination planning with distributed generation. Impact of dg on distribution protection system coordination.
Thus, in the beginning of this chapter it is discussed the main protection system issues that may arise from the high penetration of distributed generation, such as loss of protection coordination, overvoltage, loss of protection sensitivity, directional false tripping, unwanted fuse blowing, beside others. Impact of distributed generation on distribution system. Power plant and transmission system protection coordination. Pdf protection coordination for a distribution system in. Therefore, it is of interest to propose an expert system for protection coordination of distribution system under the presence of distributed generators. Coordination of overcurrent relay in distributed system for. Device settings data for fault protection devices are retrieved, including multiple preconfigured settings for some devices. Over the past decade, several research works have proved the benefits of distributed generation dg, especially which based on renewable resources, e. In this paper in order to ensure that protection of the system remains reliable even after introduction of dg is studied key protection challenges of the dn with dg and established rules for the design and coordination of protective relays in a power system. Two different case studies which are considered in present work for protection coordination include. Provides a trip of the distributed resource on undervoltage if it is islanded with local load or is subjected to a prolonged system fault. Planning the coordination of directional overcurrent. Misoperations of generation protection during the u.
Effective control of shortcircuit current, or fault current as it is commonly. Protection coordination for a distribution system in the presence of distributed generation article pdf available in turkish journal of electrical engineering and computer sciences 251. The proposed protection scheme takes into account the issues faced by traditional backup protection, such as difficulty in setting parameters and complex cooperation, and considers the features of distribution networks. Impact of distributed generation on distribution systems. It also covers the application of negativesequence overcurrent and directional overcurrent protection in distribution systems. The presence of distributed generation dg units in distribution systems increases. Analysis of distribution network protection issues in presence of dispersed generation. Distributed generation dg for resilience planning guide. Pdf planning and coordination of relay in distribution.
The course provides basic guidelines for overcurrent device coordination in radial systems. Challenges and solutions umair shahzad, salman kahrobaee, sohrab asgarpoor department of electrical and computer engineering, university of nebraska lincoln, lincoln, nebraska, usa abstract distributed generation dg is. Protection considerations for distributed generation. Distribution protection coordination issues smart grid microgrid and dg impact of ieee 1547a a word on system control with dg. Such as differential protection schemes, a balanced combination of different types of dg units for grid connection, inverter controller. Progress on protection strategies to mitigate the impact of. Distributed generation diversity level for optimal investment planning. Implementation of optimal protection coordination for. Researchers are faced with many challenges to the accurate implementation of protection schemes for dgconnected distribution network. Both new and conventional stakeholders are building or planning to build distributed solar photovoltaic systems, energy management systems, microgrids, demand services, aggregated generation behind the retail meter, and many other types of distributed generation.
This technology allows the bidirectional flow of power within an electrical network. Protection coordination of properly sized and placed distributed. Groundfault protection of low voltage systems is a considerable problem because of the presence and nature of lowlevel arcing groundfaults. Challenges and solutions umair shahzad, salman kahrobaee, sohrab asgarpoor department of electrical and computer engineering, university of nebraska lincoln, lincoln, nebraska, usa abstract distributed generation dg is the future of energy. Protection coordination, distribution networks, distributed generation dg, etap, recloser. The dg for resilience planning guide the distributed generation dg for resilience planning guide provides information and resources on how dg, with a focus on combined heat and power chp, can help communities meet resilience goals and ensure critical infrastructure remains operational regardless of external events. Master of science thesis in electric power engineering.
One of the ways for decreasing dg effects on the coordination of protective devices. Available online 2 august 2016 abstract this paper presents an adaptive protection coordination scheme for optimal coordination of docrs in interconnected power networks with the impact of dg, the used coordination technique is the arti. Distributed or dispersed generation may cause various complexities to the operation of distribution system. Grid operations manager operating effectiveness networks operating division. Distributed generation dg allows collection of energy from many sources and may provide lower environmental impacts and improved security of supply 3 dg interconnection protection what is dg. Impact of distributed generation on distribution systems and its protection. The location and capacity of dg units can influence on probability of protection maloperation in distribution networks. Effect of distributed generation capacity on the coordination of protection system of distribution network j. Introduction to protective device coordination analysis. Archived protection coordination planning with distributed. Adaptive protection coordination scheme for distribution. Pdf protection coordination with distributed generation in. Therefore, new protection coordination schemes are required for providing the adequate protection coordination for distributed energy resources connected electric power networks. Kamyab c 110 2010 ieeepes transmission and distribution conference and exposition.
A method for automatic protection coordination in a power system network comprises identifying radial sourcetoload paths and fault protection devices in the sourcetoload paths, for a portion of the power system network to be coordinated. Studying and planning of timeselective protection schemes is most conveniently carried out using selectivity diagrams. In particular, operation conflicts between distribution protection and dg are discussed with reference to unforeseen increase in short circuit currents, lack of coordination in protection schemes, ineffectiveness of line reclosing after a fault using automatic reclosing devices, undesired islanding and untimely tripping of dg interface protections. Technical and economic impacts of distributed generation. Device coordination ieee pes boston section technical meeting october 2011. Abstractintroduction of distributed generation dg to the power system may lead to nonselective protection actions. Optimal distributed generation planning in radial distribution networks considering protection coordination limits m. Impact of distributed generation on distribution system by angel fernandez sarabia department of energy technology a dissertation submitted to the faculty of engineering, science and medicine, aalborg university in partial fulfilment for the degree of master graduate june 2011 aalborg, denmark. National grid standards for in terconnecting distributed generation 12109 ieee pes boston section technical meeting october 2011. Pdf protection coordination planning with distributed generation. Novel methods for assessing the protection impacts of distributed generation in distribution network planning thesis for the degree of doctor of technology to be presented with due permission for public examination and criticism in sahkotalo building, auditorium s1, at tampere university of technology, on the 5th of december 2007, at 12 noon. One way to reduce the effects of distributed generation protection system of distribution systems is recoordination of protective devices. Prior to nrel, michael spent nearly 20 years in the electric utility industry, where he focused on electric distribution. Analysis of distribution network protection issues in.
Abdelgalil and others published protection coordination planning with distributed generation find, read and. Secrest, pe vice president technical business development threec engineering ser icesc engineering services. Proceedings of the 14th international middle east power systems conference mepcon10, cairo university, egypt, december 1921, 2010, paper id 190. The schemes designed must satisfy the performance requirements of selectivity, reliability, and sensitivity. Pdf methodology and design of an adaptive overcurrent. Proceedings of the 14 a classification technique for.