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Issue 28 - September 1999
Beckwith Electric is proud to announce the M-3425 Generator Protection System -The latest addition to their IPS (Integrated Protection Systems®) line of products. In 1995, Beckwith Electric had introduced the M-3430 Generator Protection Relay for high-impedance generators and the M-3420 Generator Protection for low impedance generators. These two products covered a broad range of generator protection needs, regardless of the generator size or type of prime mover According to Dr. Murty Yalla, VP of Research & Development/Engineering, "Beckwith Electric is committed to continued research and providing our customers with the latest technology. By keeping current with digital signal processor technology, we were able to integrate all the protective functions required for generator protection into the M-3425 Generator Protection System."
The M-3425 Generator Protection System is available to provide protection for generators of all sizes. Lew Roberson, VP of Marketing for Beckwith Electric, says, "In response to customer requests, we added more functionality to meet specific applications and enhanced the "pick and choose" software to provide users with tailored applications at the lowest possible cost. We also expanded our IPScom® Communications Software to provide simple and logical relay setting. I'm sure that users will be pleased with the results of these enhancements." New protective functions of the M-3425 Generator Protection System Include:
According to Chuck Mozina, Manager of Application Engineering for Protection and Protection Systems at Beckwith Electric, "These new protective functions are important to the complete electrical protection of generators, Beckwith Electric is the first U.S.-based relay manufacturer to provide all these functions in a digital multifunction relay" Field Ground (64F) Protective Function Although a single field-ground fault will not affect the operation of a generator or produce any immediate damaging effects, the first ground fault establishes a ground reference thereby making a second ground fault more likely. This will increase the stress to ground at other points in the field. A second ground fault will cause extensive damage by: shorting out part of the field winding causing high unit vibrations, causing rotor heating from unbalanced currents, and arc damage at the points of the fault. The 64F field ground relay must reliably detect the first ground fault so that action can be taken either through unit tripping or operator alarm to avoid continued field winding insulation deterioration that would cause a second ground fault and major damage.
As shown in the Field Ground Diagram, the M-3425 Generator Protection System measures the insulation resistance between the rotor field and ground. The relay injects a ±15 volt squarewave signal and measures the returning signal to calculate the insulation resistance. The dual-setpoint 64F function setting is in ohms. The injection frequency setting is adjusted to compensate for the field capacitance. The relay will analyze the signal rise time of the returning signal and can determine if the field brushes are making good contact with the shaft or are beginning to open. This added feature provides an alarm to the operator. Chuck Mozina states, "The injection scheme for detection of field ground faults is a major improvement over traditional voltage schemes in terms of sensitivity as well as security. The injection scheme has been widely used in Europe with great success and is now available in a relay made in the U.S." Out-of-Step (78) Protective Function Out-of-step protection, or OSP, provides generator tripping when the generator loses synchronism with the power system-that is, when the generator slips a pole. This situation occurs when the system short circuits are not cleared fast enough. Very little real power flows into the system during a three-phase fault but the internal generator voltage phase angle advances during a short circuit. If the fault is left on the system too long near a power plant, the generator can lose synchronism after the fault is cleared. OSP is needed in three situations: when a generator's "critical switching" time is short enough to warrant concern, when the unstable condition swing loci passes through the generator or its step-up transformer, or when the swing loci passes through the transmission lines close to plants but the line relays cannot detect this event. The M-3425 Generator Protection System provides this crucial function for all of these situations using an impedance-based "single blinder" relay scheme. Split-Phase Differential (5013T) Protective Function Generators with multi-turn coils and two or more windings per phase use the split-phase differential scheme to detect turn-turn faults. In this scheme, the stator windings are split into two equal winding groups and the currents of each group compared. A difference in these currents indicates an unbalance caused by a turn-to-turn fault. A definite time overcurrent function, such as that in the M-3425 Generator Protection System, is usually used to detect the current unbalance. The M-3425 also has separate pick-up levels on each phase to accommodate the practice of removing shorted turns. Stator Thermal Overcurrent (51T) Protective Function The M-3425 Generator Protection System provides this function for It thermal overload protection for the stator winding of the generator. The relay uses l2t=K for short-time heating using positive sequence current.
Click above for a larger version of the M-3425 one-line diagram. Standard vs. Premium Protective Functions The M-3425 Generator Protection System is available with Standard Protective Functions, Premium Protective Functions, and Optional Features. This provides users flexibility in selecting a protective system to best suit the application. The M-3425 may be purchased as a Protection System that includes all Standard Protective Functions. Additional Premium Protective Functions may also be added. The M-3425 may also be purchased as a Base System, with the user selecting any ten Standard Protective Functions. Additional Standard Functions or Premium Protective Functions may also be added. Standard protective functions include:
Additional standard features Include:
Premium protective functions Include:
Optional Features include dual power supply, Target Module, Human Machine Interface (HMI) Module, and the M-3801A IPSplot Oscillograph Analysis Software that allows users to display, print and analyze oscillograph data downloaded by IPScom Communications Software. Benefits The major benefits provided by digital relay technology, as designed into the M-3425, are numerous. Panel space is reduced which means a digital relay is more economical and has a lower per-function price. These factors make it ideal for generator upgrade projects. Other advances include the flexibility of the "pick and choose" functions, communication capability, system integration, self-diagnostics that can reduce future maintenance and the built-in oscillographic capability. The M-3425 Generator Protection System joins the other members of the IPS family-the M-3310 Transformer Protection relay, introduced in the summer of 1998, and the M-3520 Intertie Protection relay, introduced in March of this year. Interested? For more information, contact Beckwith Electric at (727) 544-2326 or e-mail at marketing@beckwithelectric.com.
Autodaptive® Tapchanger Control Beta-Site Tested by Andrew P. Craig, P.E., Manager of Research & Design, Controls
Instead of performing tapchanges in a deterministic manner as with previous controls, the ATC adapts to its environment to optimize tapchanger operation by reducing the overall number of tapchanges, and providing tighter voltage regulation as evidenced by a lower VRQF. VRQF, or Voltage Regulation Quality Factor, is defined as the rms deviation of the voltage from a reference voltage as recursively averaged over a moving six hours. The initial design of the control provided a testing platform. It was the first control to use the SLIMcom® Communications Software. These Beta units were initially placed in a substation of a major Florida utility that had already been an active participant in the Autodaptive® Beta-site test program of the M-2501A ACC (Autodaptive® Capacitor Control). These controls switch pole-top capacitor banks on distribution feeders based on long-term voltage profiles, setpoint voltages, and average voltage changes from switching, measured at the bank location. Using the ATC on the transformer powering the feeders with the ACCs, the effect of the ACC's on the overall VAr profile of the system could be reviewed. This was facilitated by the extensive data logging capabilities of the ATC. It can store data parameters such as measured voltage, VRQF, voltage setpoint, secondary current, primary Watts, primary VArs, power factor, and time and date. If the data is taken in five-minute intervals, the control can store all these parameters for 111 days before writing over any of the data. The control has a unique separate data storage capability. It will store 10 seconds worth of fundamental measured voltage data collected 20 times per second prior to the last four power outages. With these capabilities, Beckwith engineers were able to see the overall results of the ACC's controlling pole-top capacitor banks. To prevent periodic trips to the substation to download data, the controls communicated to a cellular telephone modem through an optically-isolated serial port to a PC. The PC could then be accessed externally by telephone through the cellular modem. The results obtained from the ATC showed a general flattening of the VAr profile due to the ACC'S, but the overall power factor was still lagging. This was improved with the addition of more banks, but the system was still not reaching unity power factor, This led to the development of the "VAr bias" algorithm. In February, the first prototypes of the ATC with VAr bias were introduced to the substation. VAr bias is the ability of the control to temporarily raise or lower the target bandcenter to influence the ACC's to switch off or on respectively. The result brought about an improvement by moving the VAr profile closer to unity. The ATC can look at overall VAr requirements at the substation, and use VAr bias to optimize the operation of the ACC's to a greater degree than can be accomplished by the ACC's alone. This is accomplished by the ATC having the VAr data real-time in conjunction with setpoint values of the transformer impedance and the size of the largest pole-top capacitor bank connected on the feeders. When the ATC measures a lagging VAr presence above a threshold value, it biases the output voltage level down by one bandwidth, to induce ACC's to switch their banks on more quickly. When the VAr profile goes leading over a threshold value, the ATC can raise the output voltage level by one bandwidth, to induce the ACC's to switch off their banks more quickly. The result on feeders with adequate numbers of capacitor banks is a constant near unity power factor. The final touch was to implement a fixed voltage setpoint in the ACC's to ensure their response to the VAr bias algorithm. The result was a VAr profile that ran weeks with no consistent deviation greater than 1 MVAr from unity power factor. Interested? For more information, contact Beckwith Electric at (727) 544-2326 or e-mail at marketing@beckwithelectric.com.
For over a decade, Beckwith Systems Engineering (BSE) has provided customers with system solutions to power problems. BSE develops replacement systems using existing Beckwith Electric products; integrates equipment into new installations: and designs new products and systems These system solutions include products for LTC control systems and paralleling, motor bus transfer systems, protection systems, and synchronizing systems.
Engineered Solutions. Relying on the full line of Beckwith protection and control products. BSE engineers identify customer project requirements designing solutions with an eye to both budget and deadline. They are committed to meeting customer needs and ensuring compliance with individual operating practices. They recognize the uniqueness of each project, and are committed to creating systems of superior design and construction. Installation and Commisioning Supervision. To minimize the chances of unforeseen and costly delays, BSE engineers provide expert supervision for installation, acceptance and operational testing of Beckwith systems. Field Services. Coordinating closely with each customer BSE brings not only expertise but also the proper test, repair, calibration and recertification equipment to the job-site, ensuring maximum operating performance. Seminars, Workshops & Hands-On Instruction BSE provides training, from application through repair procedures, for Beckwith Electric products. Seminars and workshops are available either at Beckwith's Florida headquarters or at a customer's facility. Training sessions are tailored to meet the specific needs of individual customers. Personnel. The BSE staff includes Tom Branch, Senior Project Engineer, Frank Lau, Senior Project Engineer, and Armand Tetreault, Field Service Engineer. Tom Branch has been with Beckwith Electric for over thirteen years, beginning as a design engineer responsible for the development of an advanced capacitor control and later as a project engineer for a digital signal processing-based multifunction protective relay. He was also responsible for all product line refinements including testing, customer support, and application-specific modifications Tom Branch is currently Senior Project Engineer for BSE. He is responsible for developing system products based on customers' specifications or application needs. These products include direct replacement tapchanger control panels for transformers, complete transformer paralleling systems using the circulating current method or the Delta VAr method, generator synchronizing and control systems, and motor bus transfer systems. Recently, a utility company supplied Tom with drawings for three transformers in their substation, They wanted to replace the existing control panels on each transformer with a new, upgraded panel containing the M-2001 Digital Tapchanger Control in addition to paralleling equipment. Not only were the three transformers made by two different manufacturers but they were built a decade apart and the control design differed. Tom developed a schematic for each unique panel and designed a direct mechanical replacement panel. He worked closely with the customer's project engineer, developing a bill of material for the major components from the schematic. The Beckwith Drafting Department completed the detailed mechanical design under his supervision. After the units were assembled, Tom worked with Beckwith's Quality Assurance Department to write the test procedures that verified the unit operated as designed. Tom can also provide commissioning services or on-site support for the customer. Frank Lau joined Beckwith Electric in 1985 as an electronics technician in the Quality Control Department. In 1990, he was promoted to Engineering Technician in the Engineering Department and, a year later, to Senior Engineering Technician where he performed system design, project scheduling, quality control and testing functions. A year later, Frank was promoted to Field Service Engineer where his responsibilities expanded to include field-testing and start-up commissioning, for both domestic and international sites. In 1993, he joined BSE, first as a Field Service Engineer and later as a Senior Project Engineer, Frank's responsibilities are similar to Tom's in that he develops systems based on customers' specifications or application needs. Frank, however, focuses on projects involving motor bus transfer and synchronizing-integrating Beckwith protection equipment into complete systems. Typically, Frank prepares a proposal and a quote for a custom product that he designs, develops, and for which he then provides on-site testing and commissioning. Recent projects have been so complex that they have taken over three months to complete, and have called for Frank to travel to England, Argentina and the Czech Republic for on-site testing and commissioning. Armand Tetreault, as a Field Service Engineer with BSE, is responsible for providing on-site engineering services in support of Beckwith Electric's line of protection and control products. He also conducts training on the application and testing of Beckwith equipment and systems. Armand has been associated with Beckwith Electric for the last three years, starting as a Quality Assurance Test Engineer, where he did design verification testing on Beckwith's new protection products. Armand's work ranges across the U.S. and internationally. Last year, Armand assisted Beckwith's Japanese partner, Iwatani, in commissioning two generator protection systems in Osaka, Japan. This year, Beckwith Electric has signed an agreement with Beijing's Suntech Company to represent its products in China. As part of the government's acceptance process, Armand is assisting the Chinese EPRI organization in their testing of Beckwith a new M-3425 Generator Protection Relay. BSE is comprised of a creative team of professionals committed to inventive solutions. This team identifies project requirements, design solutions, and follows through installation and commissioning to satisfy customers with reliable responsive service. The seminars and training workshops they provide are just another way Beckwith helps to maintain a standard of excellence. They offer more than quality equipment and specialized services; they provide solutions.
Clark has over twenty-five years of experience in the power industry, along with extensive international marketing expertise. Prior to joining Beckwith Electric, Clark was the Asia Segment Manager for General Electric Company's Power Management division where he was instrumental in expanding sales of protection and control products and systems. Clark also had been employed by Florida Power & Light Company for over five years, first as a supervisor of system protection engineering services and later as the system protection manager. Prior to that, he had been with General Electric Company for fifteen years as an engineer in the transmission and distribution field. Clark has a master's in electrical engineering from Union College in New York and a bachelor's in electrical engineering from the University of Wisconsin in Milwaukee, Wisconsin.
The complexity of Beckwith products he increased steadily over the years due to new communication protocols, added product functionality and new international requirements. This required more technologically-advanced equipment to assist in the development of these products, and to decrease troubleshooting time for the products leaving Engineering and going to Quality Assurance. Recent improvements include the acquisition of new equipment and personnel changes to support the growth of the engineering lab. With the new equipment, Engineering is capable of conducting a higher level of detailed testing of products before they are passed on to QA. The new environmental test chamber is programmable so that various temperature and humidity profiles can be applied to the tested products without operator intervention. The new Omicron relay test set consists of a test device and an amplifier which provide six current and six voltage sources. The magnitude, phase angle, and frequency of these sources can each be computer controlled. The test set also provides timing functions allowing changes in operating parameters or any of ten binary input to start and stop the timing functions. This test set has the versatility needed to test complex protective relay functions and control functions. Various other pieces of general-purpose test equipment, such as meters and power supplies, have also been added to the lab. To complement the expansion of the engineering lab, two additional engineering technicians have been hired. Cyrill Lobo, Engineering Tech 11, was hired to conduct firmware evaluation of control and protection products, He came to Beckwith with twelve years of experience in electronic systems testing and is currently testing the M-2001B Digital Tapchanger Control and M-2670 Autodaptive® firmware. Laura Vaccaro, Engineering Tech I, was hired to complete prototype assembly and hardware testing. She has completed assembly of the M-3425 Generator Protection Relay prototypes and hardware tests of the M-2670 line of voltage regulator controls. Other personnel changes include David Montigny's promotion to Engineering Tech II. David started as an electrical technician in Beckwith's QA Department over three years ago and was soon promoted to a lab technician. He now plays an important role by developing software for automated testing of the protective relays. Joel Bryant, who has spent several months in the purchase of the new equipment and hiring of personnel, has been promoted to Engineering Lab Supervisor. He started with Beckwith Electric fourteen years ago as an electronics technician in QA. A year later, he joined Engineering as an engineering technician. Because of the recent acquisition of new equipment and personnel changes, the detail level of testing in the engineering lab has increased dramatically. The ultimate goal of the engineering lab is to detect product design defects earlier in the design cycle, before the product ever reaches QA.
ISO 9001 Update: Continuous Improvement ISO 9001 is an International cross-industry, standard for quality systems. To become ISO 9001 certified, a company must document their procedures comply with the documentation, record the compliance, hold verification audits, and use company experience to evolve documentation and processes. This requires a company to become more methodical and more reliant on teamwork. At the end of the documentation process, and after internal audits, an independent registrar audits the quality system and, if the company passes, issues a certificate of compliance. Simply, ISO 9001 requires that you say what you do, do what you say, prove it, and improve it. For sixteen months between 1995 and 1997, representatives from each department of Beckwith Electric documented their job processes and implemented new processes to meet the elements of ISO 9001. Beckwith Electric became ISO 9001: 1994 registered on April 28th, 1997. Since then, dozens of audits have been performed to help ensure that Beckwith continues to follow and improve these processes. Thirty-six of these audits were performed last quarter alone by audit teams both internal and external to the company. External "surveillance" audits are performed annually by representatives from NSF-ISR, the International Strategic Registrations division of NSF International. NSF is a not-for-profit organization that provides third party conformity services and is an American National Standards Institute, or ANSI, accredited ISO-9000 registrar. Internal audit teams are formed by employees that volunteer to participate. These employees are sent to ISO training conducted by a local university to help them gain knowledge about the ISO standards. David Brooks, Quality Assurance Manager, is pleased with the employee auditors, strewing that they take these audits very seriously and do a professional job." The auditors remain on the same audit team for no mom than 3 consecutive audits. Auditors look for processes not being operated correctly and opportunities for improvement. Statistical analyses; of audit findings are posted in public areas of the company where all employees may view them. David adds, "This level of interaction with the processes allows employees to suggest opportunities for improvement, which ultimately helps Beckwith provide better products and services to our customers.
Articles from Issue 28, September 1999 of Beckwith Electric's
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The
introduction of the M-2667 ATC (Autodaptive® Tapchanger
Control) provides a new addition to the family of tapchanger controls
from Beckwith. Already included are the analog product line consisting
of the M-0067 LTC Control and the M-0270 series of LTC and regulator controls,
and the M-2001 Digital Tapchanger Control with its series of adapter panels.
The Autodaptive® product line offers some unique approaches
to distribution voltage control.
Clark
Shaughnessy was appointed as the Regional Sales Manager for the Pacific
Rim last month. He will be responsible for the Pacific Rim markets and
will continue to develop the sales representative network within these
countries.