2021 74th Conference for Protective Relay Engineers (CPRE)最新文献

{"title":"Case Studies in Analyzing Transformer Installation Faults – Part 1","authors":"Sudipta Maiti","doi":"10.1109/CPRE48231.2021.9429727","DOIUrl":"https://doi.org/10.1109/CPRE48231.2021.9429727","url":null,"abstract":"The events in this case study took place within a year of commissioning of Station Transformer # 1 & 2 at a newly commissioned Generating Station of 2 * 500MW Units. The case study analyses the reason of mal-tripping of High Impedance REF Protection during out-zone faults due to wrong maximum through fault current assumptions in REF Stabilizing Resistance calculations. It teaches us to use the maximum of 1LG and 3LG fault current as the through fault current for calculation of RS.","PeriodicalId":405115,"journal":{"name":"2021 74th Conference for Protective Relay Engineers (CPRE)","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115063443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effective System Grounding. Analysis of the effect of High penetration of IBRs","authors":"Sebastien C. Billaut, A. R. Miles, Chapman Brittany N., Johnson Joseph C., Colleen T. Konsavage, Praveen K. Kumar","doi":"10.1109/CPRE48231.2021.9429857","DOIUrl":"https://doi.org/10.1109/CPRE48231.2021.9429857","url":null,"abstract":"The transmission system has been grounded since its interconnection began in the 1900s. For over a century, generation was overwhelmingly provided by rotating machinery, and industry standards were implemented to keep the grounding effective. With the growing interconnection of large quantities of electronic power sources (inverter-based resources, for example) on the transmission system, some underlying assumptions related to the sources being rotating machinery are no longer valid. Consequently, traditional system grounding practices must be reexamined to ensure proper grounding as the transmission system evolves. This paper reviews why transmission systems are designed to be grounded, then discusses ways to keep the system grounded when most of its generation sources are inverters.","PeriodicalId":405115,"journal":{"name":"2021 74th Conference for Protective Relay Engineers (CPRE)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116302041","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interoperability of Line Differential Protection","authors":"J. Blumschein, T. Kerger, R. Matussek","doi":"10.1109/CPRE48231.2021.9429837","DOIUrl":"https://doi.org/10.1109/CPRE48231.2021.9429837","url":null,"abstract":"Line differential protection is used for a long time to protect overhead lines and cables in transmission and distribution systems. The basic principle of line differential protection is Kirchhoff’s current law. Due to this principle line differential protection is strictly selective to clear faults on the protected line.To apply Kirchhoff’s current law a line differential protection needs the currents from both ends of the protected line. The currents from the local end can be measured directly by means of current transformers, connected to the line differential protection device. The remote end currents however cannot be measured directly by the local line differential protection device. In general, the remote end currents are measured by a line differential protection device of same type and afterwards sent via communication link.Due to bandwidth restrictions of the communication link, differences in pre-processing of the measured values and other device specific implementations there is no interoperability of line differential protection. In general line differential protection requires both devices to be from the same manufacturer. Often the same device type or even the same firmware version is required. Today there is no interoperability for line differential protection. In case one substation gets an update of the line differential protection, the remote substation needs an update of the related line differential protection too.This paper describes an actual case how interoperability was achieved for line differential protection of different protection platforms of one manufacturer. The problems and limitations for this use case are explained in detail.In addition to this the paper suggests an implementation of line differential protection based on sampled measured values and GOOSE according to IEC61850 and IEC61869. With this approach, the communication interface between the line differential protection devices becomes interoperable. More flexible solutions are found to be possible. For instance, a line differential scheme might consist of only one line differential relay, receiving sampled measured values from a merging unit located at the remote end. The trip command for the remote end might be transferred back via GOOSE to the merging unit located at the remote end. For redundancy even two different line differential protection relays could be used feeding each other with the sampled measured values from the remote end.","PeriodicalId":405115,"journal":{"name":"2021 74th Conference for Protective Relay Engineers (CPRE)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134147472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Testing IEC-61850 Sampled Values-Based Transformer Differential Protection Scheme","authors":"Mohit Sharma, Lam Nguyen, Sughosh Kuber, Dinesh Baradi","doi":"10.1109/CPRE48231.2021.9429855","DOIUrl":"https://doi.org/10.1109/CPRE48231.2021.9429855","url":null,"abstract":"Following the successful implementation of IEC 61850 at station level over the last decade and enough user-experience on the standard, the significance of process-oriented communication using process bus is on an exponential rise. One of the key components of a process bus is information exchange among the devices through Sampled Values. Sampled Values (SV) are used for transmitting digitized values of currents and voltages on ethernet frames. With increase in industry acceptance of SV compliant protective relays, there is a crucial need for testing these relays and systems to ensure they meet operational and commissioning standards.Functional testing of SV-based protective relays with the help of a test equipment that can publish SV streams can be seen as a first step. This paper will discuss in detail on how to test through fault conditions, pick-up, slope characteristics, and harmonic restraints on a transformer differential relay that utilizes process bus to subscribe to current samples. Additionally, this paper will also discuss the effect of network anomaly and the importance of time synchronization in a process bus-based transformer differential scheme.","PeriodicalId":405115,"journal":{"name":"2021 74th Conference for Protective Relay Engineers (CPRE)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134359194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"How a Measurement You May Not Be Doing Can Improve Relay Operations Presented at the Texas A&M 74th Annual Conference for Protective Relay Engineers","authors":"Chase Lockhart, Adam Fox","doi":"10.1109/cpre48231.2021.9429715","DOIUrl":"https://doi.org/10.1109/cpre48231.2021.9429715","url":null,"abstract":"Orlando Utilities Commission (OUC) discovered that even one seemingly small error could produce an 18.5% deviation in calculated zero sequence impedance value. The utility began measuring transmission line impedance to analyze different scenarios including underground cable sections, mutually coupled lines, and neighboring utility distribution lines. By comparing values from the collected field-tested impedance data, OUC and Leidos improved the 18.5% zero sequence impedance error between OUC’s CAPE model and actual transmission line field measurements. The error was corrected when the neutral conductor on an offset distribution line near the 230kV transmission line was modeled. This paper discusses how utilities can identify and measure assets that can impact their zero sequence impedance the most. Accurate data results in more effective relay operation, and overall improved relay settings. A conference attendee will take away a better understanding of the impact different parameters have on calculating zero sequence impedance and how to get an accurate zero sequence impedance in the models. Topics include how engineers can calculate zero sequence line impedance, determine the highest priority parameters, and using transmission modeling software to model a variety of parameters including standard tower designs, conductor types, temperature, and distribution lines. Many times, the distribution system is not accounted for even though it has a significant impact on zero sequence impedance.","PeriodicalId":405115,"journal":{"name":"2021 74th Conference for Protective Relay Engineers (CPRE)","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116020105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of IEC 61850 Edition 2 on the Object Modelling of Complex Multifunctional Protection IEDs","authors":"A. Apostolov","doi":"10.1109/CPRE48231.2021.9429832","DOIUrl":"https://doi.org/10.1109/CPRE48231.2021.9429832","url":null,"abstract":"Edition 2 of IEC 61850 is the next step in the evolution of the standard that improves its functionality in order to better serve the Smart Grid. The paper discusses the changes in the object modelling of multifunctional transformer protection IEDs and how they improve the efficiency of engineering and maintenance of protection and control systems.","PeriodicalId":405115,"journal":{"name":"2021 74th Conference for Protective Relay Engineers (CPRE)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126218774","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Factors influencing CT saturation and its implications on Distance Protection Scheme-Analysis and Testing","authors":"Sughosh Kuber, Mohit Sharma, Abel Gonzalez","doi":"10.1109/CPRE48231.2021.9429851","DOIUrl":"https://doi.org/10.1109/CPRE48231.2021.9429851","url":null,"abstract":"The behavior of the Current Transformer (CTs) is of utmost importance for protection engineers to ensure reliable operation of power system. CT magnetic saturation is a well-known phenomenon when analyzing its performance characteristics. Nevertheless, transient conditions in the system might be different every time. A good understanding of the magnetic saturation of different CT designs and the effect of saturation on the protection schemes is imperative for developing a robust and dependable protection system.In this paper, various factors that affect CT saturation like X/R ratio, large current magnitudes, DC offset, burden and magnetization remanence are discussed. Analysis of CT saturation based on changes to burden and remanence is performed. In addition to that, the effect of saturation due to these factors on distance protection are presented with test results and analysis. Saturation conditions are analyzed on mho distance elements during phase to ground and three phase faults. Finally, a practical approach to efficiently test the performance of protection schemes under CT saturation conditions is proposed using COMTRADE play back. COMTRADE play back files for various scenarios of CT saturation conditions are generated and used for testing the performance of the protection scheme.","PeriodicalId":405115,"journal":{"name":"2021 74th Conference for Protective Relay Engineers (CPRE)","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122493915","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PRactical Aspects Of Designing Safe And Compact Mv Switchgear Using “Air Core Ct”, “Resistor Voltage Divider VT” And Modern Intelligent Microprocessor Relays","authors":"P. Milovac, Joe Xavier, Leslie Holloway, Stevan Davidovich, Chenkun Zheng","doi":"10.1109/CPRE48231.2021.9429853","DOIUrl":"https://doi.org/10.1109/CPRE48231.2021.9429853","url":null,"abstract":"Advancements in measurement and protection technology lead to the development of low-energy-analog (LEA) output signals in modern medium voltage switchgear design. Traditionally, medium voltage switchgear with rating 5kV-38kV uses iron cores, current transformers, and voltage transformers combined with the protective relays and metering equipment. With the new approach, iron core current transformers are replaced with LEA aircore-current-transformers (aCT), popularly known as Rogowski Coil, and voltage transformers are replaced with capacitive or resistive voltage divider (VD). IEC 61850 GOOSE and Sample Value communication technology available in modern intelligent microprocessor relays further improves the efficiency and reliability of protection and control schemes by better network communication and eliminating most copper wiring within the gear. With the apparent benefits of these advanced technologies, several specific areas of switchgear design improved. This paper discusses practical aspects and advantages of the new technologies and design considerations of an MV switchgear lineup, emphasizing conformance testing.","PeriodicalId":405115,"journal":{"name":"2021 74th Conference for Protective Relay Engineers (CPRE)","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122759076","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ground Fault Protection of Microgrid Interconnection Lines Using Distance Relay with Residual Voltage Compensation","authors":"Y. Yin, A. Zamani, Z. Zhang, Y. Fu","doi":"10.1109/CPRE48231.2021.9429847","DOIUrl":"https://doi.org/10.1109/CPRE48231.2021.9429847","url":null,"abstract":"Protection of utility feeders that supplies an ungrounded/impedance-grounded Microgrids (MGs) or Distributed Energy Resources (DERs) is a challenging task, especially for Single-Line-to-Ground (SLG) faults. Normally, the interconnection line can be protected using: (i) a Direct Transfer Trip (DTT) from the utility station and/or (ii) an over-voltage relay (59G) energized by a broken-delta potential transformer on the utility side of the interconnection transformer. However, the cost associated with the installation of a communication system to enable DTT scheme can be excessive. Further, proper settings of the 59G relay to ensure selectivity is not always possible, that is, longer operating times will be required to make sure the protection will not operate for an external fault. More importantly, an SLG fault on the utility feeder is seen as a phase-to-phase fault by the interconnection relay at the MG/DER side of the connection with lower fault current, which makes the interconnection protection more challenging.This paper studies the use of phase distance relay at the MG/DER side of the interconnection transformer to provide coordinated protection against ground faults on the utility side. The apparent impedance measured by the phase distance relay is not accurate if traditional methods are used. The study shows the closer the fault to the relay, the higher the apparent impedance seen by the relay. Therefore, it is proposed to utilize residual voltage compensation method to solve this issue such that the phase distance relay can correctly identify the SLG fault, accurately measure the apparent impedance, determine the fault location, and reliably isolate the fault without jeopardizing the stability of downstream system (i.e., MG/DER) and/or causing dangerous overvoltage/arcing conditions.","PeriodicalId":405115,"journal":{"name":"2021 74th Conference for Protective Relay Engineers (CPRE)","volume":"253 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133884124","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Complex Faults: Using High-Quality Waveform Data to Understand Faults that Misbehave","authors":"B. Russell, C. Benner, J. Wischkaemper, Karthick Muthu-Manivannan","doi":"10.1109/CPRE48231.2021.9429725","DOIUrl":"https://doi.org/10.1109/CPRE48231.2021.9429725","url":null,"abstract":"Oscillography provides users data which can be used to analyze fault behavior. In digital relays, fault recording is often an “add-on” function that supplements the core mission of protection, rather than an integral component. For well-behaved faults, recordings from relays may provide sufficient information to determine a reliable sequence of events. Many faults, however, are not well-behaved, and it is these faults which are often the most important to analyze. It is not uncommon for faults on distribution systems to show substantial dynamic behavior over many seconds, including significant changes in fault current magnitude and/or phase involvement. In these cases, fault recordings from relays often have severe limitations in their ability to help utilities diagnose the root cause of underlying events and/or determine a reliable sequence of events.","PeriodicalId":405115,"journal":{"name":"2021 74th Conference for Protective Relay Engineers (CPRE)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130134658","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}