Handbook of Electrical Design Details, Second Edition. Title: Handbook of Electrical Design Details, Second Edition. Publisher: Mc. Graw- Hill: New York, Chicago, San Francisco, Lisbon, London, Madrid, Mexico City, Milan, New Delhi, San Juan, Seoul, Singapore, Sydney, Toronto. Copyright / Pub. Date: 2.
The Mc. Graw- Hill Companies, Inc. ISBN: 9. 78. 00. 71.
Authors: Neil Sclater is the author of this Mc. Graw- Hill Professional publication.
Description. The right book for the.
TRANSMISSION LINES DESIGN and ELECTRICAL ENGINEERING HUB. If a short circuit is applied to the terminals of a synchronous generator, the short- circuit current starts out at a high value and decays to a steady- state value some time after the inception of the short circuit.
Since a synchronous generator continues to be driven by its prime mover and to have its field externally excited, the steady- state value of short- circuit current will persist unless interrupted by some switching means. An equivalent circuit consisting of a constant driving voltage in series with an impedance that varies with time is used to represent this characteristic. The varying impedance consists primarily of reactance. Xd. In about 0. 1 s reactance increases to. Xd'= transient reactance; assumed to determine current after several cycles at 6. Hz. In about 0. 5 to 2 s reactance increases to. Xd = synchronous reactance; this is the value that determines the current .
Transmission & Distribution World magazine covers overhead transmission topics in the power delivery industry, including maintenance and operations, construction and. Learn from Analog Dialogue’s technical journal – the engineering resource for innovative design. By: Neil Sclater Abstract: The right book for the “need-to-know,' practical aspects of electrical power who want to get “up to.
Amidon Transmission Line Transformer Handbook
Electrical substation - Wikipedia. Elements of a substation. A: Primary power lines' side B: Secondary power lines' side. Primary power lines 2. Transformer for measurement of electric voltage. Current transformer 8. Lightning arrester.
Secondary power lines. A 5. 0 Hz electrical substation in Melbourne, Australia. This is showing three of the five 2. V/6. 6 k. V transformers, each with a capacity of 1.
MVA. This substation is constructed using steel lattice structures to support strain bus wires and apparatus. This substation shows elements of low- profile construction; apparatus is mounted on individual columns.
A substation is a part of an electrical generation, transmission, and distribution system. Substations transform voltage from high to low, or the reverse, or perform any of several other important functions. Between the generating station and consumer, electric power may flow through several substations at different voltage levels. A substation may include transformers to change voltage levels between high transmission voltages and lower distribution voltages, or at the interconnection of two different transmission voltages. Substations may be owned and operated by an electrical utility, or may be owned by a large industrial or commercial customer. Generally substations are unattended, relying on SCADA for remote supervision and control.
The word substation comes from the days before the distribution system became a grid. As central generation stations became larger, smaller generating plants were converted to distribution stations, receiving their energy supply from a larger plant instead of using their own generators. The first substations were connected to only one power station, where the generators were housed, and were subsidiaries of that power station. These categories are not disjointed; for example, to solve a particular problem, a transmission substation may include significant distribution functions.
Transmission substation. In such cases, substation contains high- voltage switches that allow lines to be connected or isolated for fault clearance or maintenance.
A transmission station may have transformers to convert between two transmission voltages, voltage control/power factor correction devices such as capacitors, reactors or static VAR compensators and equipment such as phase shifting transformers to control power flow between two adjacent power systems. The largest transmission substations can cover a large area (several acres/hectares) with multiple voltage levels, many circuit breakers, and a large amount of protection and control equipment (voltage and current transformers, relays and SCADA systems). Modern substations may be implemented using international standards such as IEC Standard 6.
Distribution substation. A warning notice can be clearly seen on the . Disguises for substations are common in many cities.
Input voltage may be, for example, 1. V, or whatever is common in the area. The output is a number of feeders. Distribution voltages are typically medium voltage, between 2. V and 3. 3 k. V, depending on the size of the area served and the practices of the local utility. The feeders run along streets overhead (or underground, in some cases) and power the distribution transformers at or near the customer premises.
In addition to transforming voltage, distribution substations also isolate faults in either the transmission or distribution systems. Distribution substations are typically the points of voltage regulation, although on long distribution circuits (of several miles/kilometers), voltage regulation equipment may also be installed along the line. The downtown areas of large cities feature complicated distribution substations, with high- voltage switching, and switching and backup systems on the low- voltage side.
More typical distribution substations have a switch, one transformer, and minimal facilities on the low- voltage side. Collector substation. It resembles a distribution substation although power flow is in the opposite direction, from many wind turbines up into the transmission grid. Usually for economy of construction the collector system operates around 3.
V, and the collector substation steps up voltage to a transmission voltage for the grid. The collector substation can also provide power factor correction if it is needed, metering, and control of the wind farm. In some special cases a collector substation can also contain an HVDC converter station. Collector substations also exist where multiple thermal or hydroelectric power plants of comparable output power are in proximity. Examples for such substations are Brauweiler in Germany and Hradec in the Czech Republic, where power is collected from nearby lignite- fired power plants. If no transformers are required for increasing the voltage to transmission level, the substation is a switching station.
Converter substations. These stations contain power electronic devices to change the frequency of current, or else convert from alternating to direct current or the reverse. Formerly rotary converters changed frequency to interconnect two systems; nowadays such substations are rare. Switching station. Switching stations are sometimes used as collector and distribution stations. Sometimes they are used for switching the current to back- up lines or for parallelizing circuits in case of failure. An example is the switching stations for the HVDC Inga.
In this case the generators from the power station supply their power into the yard onto the Generator Bus on one side of the yard, and the transmission lines take their power from a Feeder Bus on the other side of the yard. An important function performed by a substation is switching, which is the connecting and disconnecting of transmission lines or other components to and from the system. Switching events may be planned or unplanned. A transmission line or other component may need to be de- energized for maintenance or for new construction, for example, adding or removing a transmission line or a transformer. To maintain reliability of supply, companies aim at keeping the system up and running while performing maintenance. All work to be performed, from routine testing to adding entirely new substations, should be done while keeping the whole system running.
Former high- voltage substation in Stuttgart, Germany, now 1. V switching station. The 2. 20k. V level is eliminated for grid simplification. Unplanned switching events are caused by a fault in a transmission line or any other component, for example: a line is hit by lightning and develops an arc,a tower is blown down by high wind. The function of the switching station is to isolate the faulty portion of the system in the shortest possible time.
De- energizing faulty equipment protects it from further damage, and isolating a fault helps keep the rest of the electrical grid operating with stability. In some cases a conversion of the current type takes place, commonly with rectifiers for direct current (DC) trains, or rotary converters for trains using alternating current (AC) at frequencies other than that of the public grid.
Sometimes they are also transmission substations or collector substations if the railway network also operates its own grid and generators. It has a facade in clay brick with grey stone ornaments, to blend in to its downtown environment. Elements of a substation. In a large substation, circuit breakers are used to interrupt any short circuits or overload currents that may occur on the network.
Smaller distribution stations may use recloser circuit breakers or fuses for protection of distribution circuits. Substations themselves do not usually have generators, although a power plant may have a substation nearby. Other devices such as capacitors and voltage regulators may also be located at a substation. Substations may be on the surface in fenced enclosures, underground, or located in special- purpose buildings. High- rise buildings may have several indoor substations.