Boston Edison Company Research Articles

The Application of Real-Time Monitoring and Rating Equipment to HPOF Pipe Cable Systems

The Boston Edison Company has installed realtime monitoring and rating systems on two independent pairs of 115 KV HPOF pipe-type cables. This paper describes these installations and gives some results of their operation. These circuits exhibited large increases in short time emergency ratings because they normally operate at relatively low temperatures. The identification of effective earth parameters in real-time generally results in increased long term and normal ratings because of the conservative assumptions that must be made at the design stage. The real-time systems are remotely located at cable terminal locations so that critical data inputs can be hard-wired to the computing processor. Real-time information is made available via analog SCADA connections and also by IBM-PC's equipped with MODEMs which can call the remote systems to view real-time conditions or unload historical data. A PC Software package compliments the real-time system and gives Planners, System Operators, and Cable Engineers the ability to simulate cable system operation in an off-line environment.

The application of real-time monitoring and rating to HPOF pipe cable systems

The Boston Edison Company has installed real-time monitoring and rating equipment on two independent pairs of 115 kV HPOF (high-pressure oil-filled) pipe-type cables. The real-time systems are remotely located at cable terminal locations so that critical data inputs can be hard-wired to the computing processor. Real-time information is made available via analog SCADA (supervisory control and data acquisition) connections and also by IBM PCs equipped with modems, which can call the remote systems to view real-time conditions or unload historical data. A PC software package complements the real-time system and gives planners, system operators, and cable engineers the ability to simulate cable system operation in an offline environment. In general, the identification of effective earth parameters in real-time is shown to result in increased emergency and normal ratings by replacing the conservative assumptions that must be made at the design stage with accurate real-time data. Lightly loaded circuits have exhibited large increases in short-time emergency ratings, as they normally operate at relatively low temperatures. >

Risk Factors in Heatstroke

To Editor.— In their article on risk factors for heatstroke, Kilbourne et al stated that the association between tree growth and heat stroke requires further (1982; 247:3332). Such clarification may already have been provided. According to Robert Little, arborist for Boston Edison Company, one large tree cools as much as five 10,000-BTU air conditioners. 1 Thus, although living in a well-shaded home may serve as a market for high socioeconomic status, as pointed out by Kilbourne et al, it should also and does correlate well with same protective effect as air conditioning. The significance of shade-tree effect should not be lost on either city planners or medical personnel attempting to prevent heatstroke. Scant financial resources spent for shade trees might well provide many more years of protection against heatstroke, much less energy expenditure, and much more beauty than same resources spent for electric fans.

Dynamic Performance of Fossil-Fueled Power Plants

Dynamic simulation is a valuable tool for optimizing the design and operation of steam electric power plants, especially those that change load or shut down frequently. However, its use has been limited because it has required experienced modeling specialists. An easy-to-use modeling system has therefore been developed under Electric Power Research Institute sponsorship. It has been tested by simulating transients performed on Boston Edison Company's Mystic Unit 7, a 550-MW oil-fired plant, with good agreement between the simulations and the recorded plant transients.

Corrosion Experience with Subway Transformers

Many of the corrosion problems confronting electric utility companies with submersible URD systems are similar to those encountered for the past twenty ( 20) years by Boston Edison Company in the operation of its underground distribution system which includes mild steel subway transformer tanks.

A microwave system for protective relaying

PIONEERING in the use of a microwave system for complete high-speed relay protection for 115-kv pipe-type cables and transfer tripping protection for associated transformers, the Boston Edison Company has had a 2,000-mc microwave system in operation for approximately one year.

A Microwave System for Protective Relaying - Boston Edison Company

A Microwave System for Protective Relaying - Boston Edison Company

4-Kv Versus 13.8-Kv Distribution on the Boston Edison Company System [includes discussion

4-Kv Versus 13.8-Kv Distribution on the Boston Edison Company System [includes discussion

Primary network installations at boston

THE BOSTON EDISON COMPANY has three primary network installations in operation on its system supplying a total load of 43,000 kva. The first primary network installation went into service in 1932 to supply a residential load of approximately 4,500 kva in an area of about 5.3 square miles. This load was supplied with four 1,500-kva transformers rated 13,800-volt primary and 4,330-volt secondary installed in underground vaults 30 feet long by 9 1/2 feet wide by 10 feet high. The transformers, as originally installed, were connected Y-Y with a tertiary-delta winding but they were later rewound for delta-Y operation in order to put the network in phase with the existing radial system which is supplied from delta-Y connected transformers.

Modernization of L Street Station Switch House, Boston Edison Company

THIS paper is being presented with several objects in view, to serve possibly as a guide or outline of procedure for companies undertaking a modernization program, to list the main items of equipment installed, to discuss why certain selections were made, and to aid engineers in studying their own stations by indicating dangerous conditions or weak equipment as found at the L Street station of the Boston Edison Company.

Modernization of L Street station switch house, Boston Edison Company

THIS paper is being presented with several objects in view, to serve possibly as a guide or outline of procedure for companies undertaking a modernization program, to list the main items of equipment installed, to discuss why certain selections were made, and to aid engineers in studying their own stations by indicating dangerous conditions or weak equipment as found at the L Street station of the Boston Edison Company.

Changes in a High-Pressure Drum to Eliminate Recurrence of Cracks Due to Corrosion Fatigue

Abstract This paper gives the results of an investigation which was undertaken for the purpose of determining the cause of the cracks found in the No. 5 boiler at the Edgar Station of the Boston Edison Company. It also discusses the cause of the cracks found in the water columns and in certain of the superheater fittings and headers of this same boiler. The boiler in question is one of the first high-pressure units installed in this country and, therefore, it was quite essential that the cause of the cracks be determined and suitable steps be taken to prevent their recurrence. The study sets forth the changes which were made. As a result of the investigation it was not felt that any of the difficulty could be attributed to faulty metal. The material was of the proper chemical composition and had suitable physical properties. The primary cause of the cracks was believed due to corrosion fatigue resulting from stresses set up by changes in temperature on the surface of the metal in combination of a relatively low pH value of the water which was at times in contact with the metal that developed cracks. As a result of the removal of the cracked metal and the changes in design which would prevent fluctuating temperatures on the surface of the drum at the boiler feedwater inlet, as well as other design changes which would raise the pH value, particularly in the water columns, it is not anticipated that further cracking will take place.

V — Hurricane experiences of power utilities in Boston Area

THE PATH of the hurricane disturbance over New England embraced the entire system of the Boston Edison Company. The wind velocity of the hurricane at the Blue Hill Observatory near Boston situated 500 feet above sea level approximated 186 miles per hour at 6:47 p.m. on the day of the storm and several sustained gusts of 111 miles per hour were recorded over five-minute periods. In general, the maximum wind velocity at the ground throughout our area was estimated to have been in the vicinity of 85 to 100 miles per hour. There was almost no rain in Boston although rain elsewhere resulted in extensive floods.

Discharge Currents in Distribution Arresters-II

TWO YEARS ago, the authors of this paper described to the AIEE a co-operative investigation by the Boston Edison Company, the Commonwealth Edison Company of Chicago, the Detroit Edison Company, the Georgia Power Company, and the General Electric Company, having as its object the determination of data relative to lightning discharge currents through distribution lightning arresters. At that time the results were based upon records obtained over a 13-month period from August 1934 to August 1935, inclusive. The object of this paper is to present the results from August 1934 to September 1937.

X-rays in Science and Industry

X-RAYS are useful to industry in two ways: first, in getting the factory out of manufacturing difficulties, and, second, in the search for new scientific principles which may serve to correlate and explain known facts or be applied to the development of new structural products. (1) Solution of Factory Difficulties Probably the first work to employ X-rays in an effort to solve factory problems was done in the Research Laboratory of the General Electric Company, at Schenectady, New York. While a large steel casting several feet in diameter and about a half-inch thick was being machined to size in the factory, a tiny crack was found in the metal. The casting was taken to the laboratory and X-ray plates were taken, which showed a large hole in the inside of the metal. The spot indicated on the plate was punched out and the hole was thus exposed to view. The use of X-rays in work of this sort was very expensive, so that other methods of testing soon were developed for smooth-faced metal, which were just as good and considerably cheaper. The X-ray inspection of castings was therefore discontinued at the General Electric Company, but it has since been taken up by the United States Government at the Watertown Arsenal, where an investigation has been made of foundry processes. Occasionally, too, the Arsenal has made X-ray plates of special castings where considerations of human safety have justified the high cost of such work. The most outstanding example of this was the X-ray inspection of some steam fittings for a new high pressure steam line of the Boston Edison Company. (2) X-ray Diffraction It is in the discovery of new facts on which to base future factory processes that we find the greatest usefulness of X-rays. Practically all work of this sort depends upon the measurement of interatomic distances, so small that they cannot be measured directly. They are of the order of 10−8 cm. By using X-rays of known frequency it is possible to use an X-ray diffraction apparatus as a micrometer for making these extremely small measurements. The technic has been refined so that such measurements may be made easily, with an accuracy of one part in a thousand. This sort of apparatus, which was developed at the Research Laboratory of the General Electric Company, is now in use in the School of Chemistry and Physics at The Pennsylvania State College in investigating the properties of metals and their alloys. By measuring these minute units, it is already possible to predict some of the mechanical properties of metals, and to tell what happens when they form alloys. It is possible to show why copper is more ductile than iron, and why iron is more ductile than arsenic. Similar measurements on tungsten make it seem that the Coolidge process now in use is the only process by which that material can be made into a ductile wire. A more detailed discussion of some of these points follows.

Temperature errors in induction watthour meters

C. H. Ingalls: For the past twelve years, the Meter Division of the Boston Edison Company has corrected for the temperature errors of its portable test meters through thermometers permanently installed in the meters. A recent occurrence illustrates how the accuracy of an uncompensated meter may be affected by certain abnormal temperature conditions.

Notes on operation of large interconnected systems

INTERCONNECTIONS have been made between the Boston Edison systems and the systems of the Eastern Massachusetts Electric Company and the New England Power Company, these two companies serving territory adjacent to that served by the Boston Edison Company.