Duquesne Light Company Research Articles

Density-based clustering algorithm for associating transformers with smart meters via GPS-AMI data

The ongoing deployment of Distributed Energy Resources, while bringing benefits, introduces significant challenges to the electric utility industry, especially in the distribution grid. These challenges call for closer monitoring through state estimation, where real-time topology recovery is the basis for accurate modeling. Previous methods either ignore geographical information, which is important in connectivity identification or are based on an ideal assumption of an isolated sub-network for topology recovery, e.g., within one transformer. This requires field engineers to identify the association, which is costly and may contain errors. To solve these problems, we propose a density-based topology clustering method that leverages both voltage domain data and the geographical space information to segment datasets from a large utility customer pool, after which other topology reconstruction methods can carry over. Specifically, we show how to use voltage and GPS information to infer associations within one transformer area, i.e., to identify the meter-transformer connectivity. To give a guarantee, we show a theoretic bound for our clustering method, providing the ability to explain the performance of the machine learning method. The proposed algorithm has been validated by IEEE test systems and Duquesne Light Company in Pittsburgh, showing outstanding performance. A utility implementation is also demonstrated.

97/02389 Slip stream test of Cannon Technology's low temperature oxidation (LTO) system at Duquesne Light Company's Elrama plant: demonstration of an oxidative process

97/02389 Slip stream test of Cannon Technology's low temperature oxidation (LTO) system at Duquesne Light Company's Elrama plant: demonstration of an oxidative process

A Comprehensive Generation Control and Dispatch System for an Electric Utility with Special Requirements

The ability to control a power system in real-time with considerations for unusual generation configurations and heavy industrial loads has become increasingly important to utility operations for a number of reasons. An Energy Control System which includes special techniques in the real-time generation control and dispatch algorithms to solve these problems has recently been delivered to the Duquesne Light Company. All generation resources, including jointly-owned units, combined -cycle units and units located external to the control system boundary, are considered for control and dispatch. Large, non-conforming, industrial loads which cause wide swings in the system's net interchange and Area Control Error, such as arc furnaces and rolling mills, have been accounted for, while still allowing the control system to respond properly to system emergencies and changes in system load.

Metal-Clad Switchgear for 23 and 34.5 kV

The extension of metal-clad switchgear with oilless power circuit breakers to the higher voltages of 23 kV and 34.5 kV has awaited the development of a suitable circuit breaker unit. Prompted by the need of Duquesne Light Company for such 23-kV equipment for their new Oakland substation, the breakers described in this article were designed and developed. As a result, indoor and outdoor metal-clad switchgear, with all of their well- known advantages, are now available for both voltage ratings up to a 1500-MVA interrupting rating and for continuous current ratings of 1200 and 3000 amperes.

Project Sherwood . The U.S. program in controlled fusion. Amasa Bishop. 228 pp. $5.75. The Transuranium Elements . Glenn T. Seaborg. 354 pp. $7. U.S. Research Reactor Operation and Use . Joel W. Chastain, Jr., Ed. 384 pp. $7.50. Radiation Biology and Medicine . Selected reviews in the life sciences. Walter D. Claus, Ed. 968 pp. $11.50. Uranium Ore Processing

<i>Project Sherwood</i> . The U.S. program in controlled fusion. Amasa Bishop. 228 pp. $5.75. <i>The Transuranium Elements</i> . Glenn T. Seaborg. 354 pp. $7. <i>U.S. Research Reactor Operation and Use</i> . Joel W. Chastain, Jr., Ed. 384 pp. $7.50. <i>Radiation Biology and Medicine</i> . Selected reviews in the life sciences. Walter D. Claus, Ed. 968 pp. $11.50. <i>Uranium Ore Processing</i>

Motor-driven exciters for turbine generators

THE PURPOSE OF this article is to point out the important factors involved and describe a reasonably simple method of calculating the required characteristics of motor-driven exciters for turbine generators. Such calculations are required to insure that the performance of the motor-generator set exciter will be comparable to that of a directly connected exciter during system disturbances. Although the method can be applied to any type of auxiliary supply system, the material in this article applies specifically to the auxiliary system in the Elrama Station of the Duquesne Light Company, Pittsburgh, Pa. A schematic diagram of this station is shown in Figure 1.

Bus transfer tests on station auxiliary system

TWO METHODS are used to transfer powerhouse auxiliary busses supplying station auxiliary motors from one source to another; namely, “closed transition” and “open transition.” For maximum safety with closed transition the feeder circuit breakers should be capable of interrupting a feeder fault when the two sources are tied together. For open transition the feeder circuit breakers have interrupting capacity to handle the short-circuit kilovolt-amperes from only one source at a time. There is an optimum time interval at which reclosure should be made on open transition to give the least disturbance and provide maximum safety to the station equipment. To determine this time interval, transfer tests were made on the auxiliary power system of the Phillips Power Plant, Duquesne Light Company, Pittsburgh, Pa.

Primary Networks on the Duquesne Light Company System

Primary Networks on the Duquesne Light Company System

A 10,000-Kva Series Capacitor Improves Voltage on 66-Kv Line Supplying Large Electric Furnace Load

Duquesne Light Company placed in service on October 26, 1947, the largest kilovolt-ampere and highest voltage-series capacitor in the world, to improve voltage regulation and alleviate voltage flicker at a large steel mill and on the line serving it. The capacitor has a nominal rating of 10,000-kva and was installed on a 66-kv line. It was built by the Westinghouse Electric Corporation. This paper presents the calculated results of system studies made prior to the authorization of the series capacitor and the reasons for selecting the series capacitor. In addition, the results of staged tests showing the starting of a large induction motor and the energizing of the power transformers at the load with the capacitor in service are included. The improvement in utilization voltage is also shown.

Development in lightning protection of stations

THE AIEE transformer sub-committee has recently sponsored a paper <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sup> on the protection of power transformers against lightning surges. The most effective method given combines overhead ground wires, line entrance gaps, and transformer mounted lightning arresters. Such a method does give a high degree of protection, but it is primarily applicable to high voltage, high capacity stations where the overhead ground wire system is justified for both line and station. The conditions noted above are seldom fulfilled on subtransmission systems from 23 kv to 34.5 kv. Effective ground wires and low ground resistances are uneconomical, and the protection provided is usually a more or less modern arrester, not always located and grounded to the best advantage. On the 23-kv subtransmission system of the Duquesne Light Company, the average transmission distance is approximately two miles. This means that most direct strokes will contact the line not more than one mile from some substation. Much of this transmission is now equipped with wood cross arm braces and guy insulators, and at some stations several spans adjacent thereto are carried on unguyed poles.

Development in Lightning Protection of Stations

THE AIEE transformer sub-committee has recently sponsored a paper1 on the protection of power transformers against lightning surges. The most effective method given combines overhead ground wires, line entrance gaps, and transformer mounted lightning arresters. Such a method does give a high degree of protection, but it is primarily applicable to high voltage, high capacity stations where the overhead ground wire system is justified for both line and station. The conditions noted above are seldom fulfilled on subtransmission systems from 23 kv to 34.5 kv. Effective ground wires and low ground resistances are uneconomical, and the protection provided is usually a more or less modern arrester, not always located and grounded to the best advantage. On the 23-kv subtransmission system of the Duquesne Light Company, the average transmission distance is approximately two miles. This means that most direct strokes will contact the line not more than one mile from some substation. Much of this transmission is now equipped with wood cross arm braces and guy insulators, and at some stations several spans adjacent thereto are carried on unguyed poles.

Large Electric-Arc Furnaces-- Performance and Power Supply

In March l940, a 25-ton Heroult 3-phase electric arc furnace using a 10,000-kva 1.5 volts (115-volt base) for the 66-kv system with fluctuations from 3 per hour up to 15 per minute. Precautions were taken in the design of the furnace transformer to include separate reactance to reduce the load swings. Subsequently, it was found that this additional reactance was not eneded and it was removed, thereby improving the operation of the furnace. The load swings and accompaning voltage changes, after disconnecting the reactance, due to the operation of the first furnace, slightly exceeded the Duquesne Light Company standards. However, no complaints have been received from adjacent customers nor have any difficulties arisen from excessive operation of 4-kv distribution regulators, operation of the power stations, or interconnections.

A Comparison of the Relative Efficiency of the Schafer and Pole-Top Methods of Artificial Respiration

The pole-top method of artificial respiration was devised by E. W. Oesterreich1 of the Duquesne Light Company, Pittsburgh, Pa., to give prompt aid in case of electric shock occurring while men are working on poles of power lines. When a worker receives an electric shock while working on a pole minutes elapse before he can be lowered to the ground and resuscitation started by the prone-pressure method. In the field, the elapsed time is seldom less than five minutes2 and in many cases it is considerably longer. The pole-top method of resuscitation was developed to reduce this period. Tests have shown that an operator can reach a man working alone on a pole and start squeezing his abdomen within approximately one minute.2 If there are two men on the pole and one receives a shock the elapsed time before the first pressure is applied is much shorter. While an operator is applying the pole-top method, other members of the line crew make preparation for lowering the victim to the ground where the prone-pressure method may be applied, should it prove necessary.

A comparison of the relative efficiency of the schafer and pole-top methods of artificial respiration

The pole-top method of artificial respiration was devised by E. W. Oesterreich <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sup> of the Duquesne Light Company, Pittsburgh, Pa., to give prompt aid in case of electric shock occurring while men are working on poles of power lines. When a worker receives an electric shock while working on a pole minutes elapse before he can be lowered to the ground and resuscitation started by the prone-pressure method. In the field, the elapsed time is seldom less than five minutes <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> and in many cases it is considerably longer. The pole-top method of resuscitation was developed to reduce this period. Tests have shown that an operator can reach a man working alone on a pole and start squeezing his abdomen within approximately one minute. <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> If there are two men on the pole and one receives a shock the elapsed time before the first pressure is applied is much shorter. While an operator is applying the pole-top method, other members of the line crew make preparation for lowering the victim to the ground where the prone-pressure method may be applied, should it prove necessary.

Lightning protection of 22-kv substations

This paper outlines laboratory and field tests with a surge generator and cathode-ray oscillograph which led to the co-ordination of insulation and lightning-arrester performance in substations on the 22-kv subtransmission system of the Duquesne Light Company.

Lightning Protection of 22-Kv Substations

This paper outlines laboratory and field tests with a surge generator and cathode-ray oscillograph which led to the co-ordination of insulation and lightning-arrester performance in substations on the 22-kv subtransmission system of the Duquesne Light Company. A basic level of 150 kv for station insulation was selected in 1932, and methods of obtaining this level are presented together with the operating record for five years. The index representing the station equipment faults in per cent of total system faults during thunderstorms has decreased 86 per cent following system-wide improvement programs modernizing insulation and arresters.

Operating Characteristics of Turbine Governors

Surging has occurred on power systems whose transmission distance is small and load density high. The Duquesne Light Company of Pittsburgh, Pennsylvania, has experienced these surges. This paper outlines tests conducted to determine the influence the steam turbine governors have in starting or sustaining a surge condition. The conclusions assumed are: 1. The governor system installed at Colfax Power Station will not start system surging. 2. The governor system will not sustain load oscillations.

Abridgment of the fault ground bus: Its use and design in Brunot Island switch house of Duquesne light company

This paper describes the ground protection in the Brunot Island switch house of the Duquesne Light Company at Pittsburgh, Pa. This switch house constructed on the vertical isolated-phase plan, is divided structurally into several completely insulated sections. The well-known fault ground bus system of protection is applied and made effective by the special features of construction not heretofore used. Details of building construction and of fault ground bus application are given. Arrangements for heating, ventilating, and lighting the buildings are such as not to interfere with phase isolation and insulation. Oil circuit breaker mechanisms are insulated where necessary to maintain insulated sections in the building subdivision. The fault ground bus location, connections, and special details of construction are outlined. Preliminary tests, relay settings, and operating results are given.

The Fault Ground Bus Its Use and Design in Brunot Island Switch House of Duquesne Light Company

This paper describes the ground protection in the Brunot Island switch house of the Duquesne Light Company at Pittsburgh, Pa. This switch house constructed on the vertical isolated-phase plan, is divided structurally into several completely insulated sections. The well known fault ground bus system of protection is applied and made effective by the special features of construction not heretofore used. Details of building construction and of fault ground bus application are given. Arrangements for heating, ventilating, and lighting the buildings are such as not to interfere with phase isolation and insulation. Oil circuit breaker mechanisms are insulated where necessary to maintain the building subdivision into insulated sections. The fault ground bus location, connections, and special details of construction are outlined. Preliminary tests, relay settings, and operating results are given.

Some Operating Data of Large Steam Generating Units

Abstract This paper gives the principal operating data of six large steam generating units fired with pulverized coal, and installed in four plants. Two of these units are the remodeled boilers of the Fordson Power Plant of the Ford Motor Company, Fordson, Michigan; the third unit is one of the first five pulverized-coal-fired boilers of the Colfax Plant of the Duquesne Light Company near Pittsburgh; the fourth unit is one of the two boilers of the Stanwix Plant of the Allegheny County Steam Heating Company in Pittsburgh; and the fifth and sixth units are the two units of the Gould Street Station of the Consolidated Gas Electric Light and Power Company of Baltimore. All these plants use the storage system of burning pulverized coal, and the units are fairly representative of the large steam generating units now rapidly coming into use. The operating data are presented graphically and consist of the hourly output in pounds of steam throughout the period of operation. Whenever the steam generating unit was shut down the reason for this shut down is given. There are also presented charts giving the necessary data for the computation of the efficiency for various percentages of rating such as the temperature of flue gases, the percentage of CO2 in the flue gases, and the losses due to incomplete combustion.