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105-740: The system contains more than 34,187 kilometres (21,243 mi) of lines and 530 electrical substations . It is managed by Hydro-Québec TransÉnergie, a division of the crown corporation Hydro-Québec and is part of the Northeast Power Coordinating Council . It has 17 interconnectors with the systems in Ontario , Newfoundland and Labrador , New Brunswick , and the Northeastern United States , and features 6,025 megawatts (MW) of interconnector import capacity and 7,974 MW of interconnector export capacity. Major expansion of

210-447: A bus plus some circuit breakers . 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 61850 . A distribution substation transfers power from

315-487: A right-of-way wider than the 80.0–91.5 metres (262.5–300.2 ft) width required for a single 735 kV line. Each 735 kV line is capable of transmitting 2,000 MW of electric power at a distance of over 1,000 kilometres (620 miles) and the entire 735 kV grid can carry 25,000 MW of power. Power transmission losses over the 735 kV grid range from 4.5 to 8%, varying due to temperature and operating situations. The Ordre des ingénieurs du Québec named

420-467: A T-shaped tower, lattice or pole, to support two bundles of three conductors on each side. The direct current power line sometimes uses two poles or a wider, pyramidal, self-supporting lattice structure for angle towers. Hydro-Québec usually uses tall, large pylons to cross large bodies of water, like lakes and rivers. These towers are said to be prominent and the tallest pylon in Hydro-Québec's power grid

525-518: A V-shaped insulator and one with shorter side crossbar, where only the middle bundle hangs from the insulator and the side bundles are strung on vertical insulator strings. During the construction of the James Bay transmission system, the cross-rope suspension tower was invented. This type of tower features two guyed-tower legs similar to the V-guyed tower, but the two legs don't converge at the tower base. In

630-581: A cleared right-of-way with a width of 216 metres (709 feet). As they head southwest through boreal forest , the lines generally traverse flat, smooth rolling hills. After the lines cross the Quebec-Labrador border, also known as the Hydro-Québec point of delivery, the direction of the lines becomes due south, and they head to the Montagnais Substation , a substation accessible only by an airport adjacent to it . A lone 735 kV line stems off from

735-413: A contractor for actual construction. Major design constraints for construction of substations include land availability and cost, limitations on the construction period, transportation restrictions, and the need to get the substation running quickly. Prefabrication is a common way to reduce the construction cost. For connecting the new substation, a partial outage at another substation may be required, but

840-697: A cost of C$ 3.1 billion alone. In less than four decades, Hydro-Québec's generating capacity went from 3,000 MW in 1963 to nearly 33,000 MW in 2002, with 25,000 MW of that power sent to population centres on 735 kV power lines. Much of the electricity generated by Hydro-Québec Generation comes from hydroelectric dams located far from load centres such as Montreal. Of the 33,000 MW of electrical power generated, over 93% of that comes from hydroelectric dams and 85% of that generation capacity comes from three hydroelectric generation centers: James Bay, Manic-Outardes, and Newfoundland and Labrador Hydro 's Churchill Falls. The James Bay Project encompasses

945-706: A disconnection of the load supplied by the circuit break from the feeding point. This seeks to isolate the fault point from the rest of the system, and allow the rest of the system to continue operating with minimal impact. Both switches and circuit breakers may be operated locally (within the substation) or remotely from a supervisory control center. With overhead transmission lines , the propagation of lightning and switching surges can cause insulation failures into substation equipment. Line entrance surge arrestors are used to protect substation equipment accordingly. Insulation Coordination studies are carried out extensively to ensure equipment failure (and associated outages )

1050-457: 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 , voltage regulators , and reactors may also be located at

1155-422: 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. Substations may be designed and built by a contractor or alternately all phases of its development may be handled by the electrical utility . Most commonly, the utility does the engineering and procurement while hiring

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1260-522: A long lease such as a renewable 99-year lease, giving the utility company security of tenure . The first step in planning a substation layout is the preparation of a one-line diagram , which shows in simplified form the switching and protection arrangement required, as well as the incoming supply lines and outgoing feeders or transmission lines. It is a usual practice by many electrical utilities to prepare one-line diagrams with principal elements (lines, switches, circuit breakers, transformers) arranged on

1365-663: A massive expansion of its 735 kV power grid and its hydroelectric generating capacity. Hydro-Québec Équipement, another division of Hydro-Québec, and Société d’énergie de la Baie James built these transmission lines, electrical substations , and generating stations. Constructing the transmission system for the La Grande Phase One, part of the James Bay Project, took 12,500 towers , 13 electrical substations, 10,000 kilometres (6,000 mi) of ground wire , and 60,000 kilometres (37,000 mi) of electrical conductor at

1470-558: A massive power outage in the cold Canadian winter. Even though power restoration initiated after the first blackouts, large numbers of Quebecers were in the dark. At the height of the blackout, some 1.4–1.5 million homes and customers, housing three to more than four million people, were in the dark. Private companies and other utilities from other parts of Canada and the United States were sent in to help Hydro-Québec undertake this massive restoration task, but these efforts were complicated by

1575-690: A ring bus, double bus, or so-called "breaker and a half" setup can be used, so that the failure of any one circuit breaker does not interrupt power to other circuits, and so that parts of the substation may be de-energized for maintenance and repairs. Substations feeding only a single industrial load may have minimal switching provisions, especially for small installations. Because of the risk of electrical shock, substations are inherently dangerous to electrical workers. To mitigate this hazard, substations are designed with various safety features. Live conductors and bare equipment are kept separate, either with protected equipment, or using screens or distance. Based on

1680-679: A substation. Substations may be on the surface in fenced enclosures, underground, or special-purpose buildings. High-rise buildings may have several indoor substations. Indoor substations are usually found in urban areas to reduce the noise from transformers, improve appearance, or protect switchgear from extreme climate or pollution. Substations often use busbars as conductors between electrical equipment. Busbars may be aluminum tubing 3–6 inches (76–152 mm) thick, or else wires (strain bus). Outdoor, above-ground substation structures include wood pole, lattice metal tower, and tubular metal structures, although other variants are available. Where space

1785-422: 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. Unplanned switching events are caused by a fault in a transmission line or any other component, for example: The function of

1890-717: A voltage of AC 735 kV to transmit and distribute electrical power produced from Hydro-Québec's dams, although 315 kV is used as well. The total value of TransÉnergie's entire electricity transmission system is C$ 15.9 billion. For these reasons, Hydro-Québec TransÉnergie is considered to be a world leader in power transmission. From 1965 onwards, the 735 kV power line became an integral part of Quebec's power transmission backbone. More than one-third of Hydro-Québec TransÉnergie's system consists of high voltage AC 735 / 765 kV power lines, totaling 11,422 kilometres (7,097 mi) strung between 38 substations with equipment of that voltage. The first transmission system from 1965

1995-602: Is aimed at minimizing cost while ensuring power availability and reliability, and enabling changes to the substation in the future. Substations may be built outdoors, indoors, or underground or in a combination of these locations. Selection of the location of a substation must consider many factors. Sufficient land area is required for installation of equipment with necessary clearances for electrical safety, and for access to maintain large apparatus such as transformers. The site must have room for expansion due to load growth or planned transmission additions. Environmental effects of

2100-637: Is an IEEE Milestone . The physical size of the Hydro-Québec's 735 kV transmission lines is unmatched in North America. Only two other utility companies in the same region, the New York Power Authority (NYPA) and American Electric Power (AEP) contain at least one 765 kV line in their power system. However, only AEP has a significant mileage of 765 kV power lines, with over 3,400 kilometres (2,100 mi) of 765 kV line traversing its broad transmission system; this system contains

2205-852: Is asynchronous with neighboring systems. Quebec will consequently be able to develop its own reliability standards, as needed, and these will apply in addition to the relevant North American standards. Besides the Quebec Interconnection , there are four other interconnections in North America: the Eastern Interconnection , the Western Interconnection , the Alaska Interconnection and the Electric Reliability Council of Texas . Hydro-Québec TransÉnergie has

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2310-482: Is based on capacitor technology. To maintain its transmission system performance, TransÉnergie sets aside funds for research and application of new technologies. In addition to power transmission technology, Hydro-Québec plans to offer high-speed internet over its transmission lines within a few years; the utility started testing internet over its lines in January 2004. In spite of the transmission system's reputation and

2415-465: Is common in the area. The output is a number of feeders. Distribution voltages are typically medium voltage, between 2.4 kV and 33 kV, 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

2520-577: Is managed by Hydro-Québec TransÉnergie, a division of the crown corporation Hydro-Québec and is part of the Northeast Power Coordinating Council . It has 17 interconnectors with the systems in Ontario , New Brunswick , Newfoundland and Labrador , and the Northeastern United States and 6,025 MW of interconnector import capacity and 7,974 MW of interconnector export capacity. The system has transmission lines reaching to power generation facilities located more than 1,000 kilometres (600 mi) away from population centers. For this reason, TransÉnergie uses

2625-402: Is minimal. Once past the switching components, the lines of a given voltage connect to one or more buses . These are sets of busbars , usually in multiples of three, since three-phase electrical power distribution is largely universal around the world. The arrangement of switches, circuit breakers, and buses used affects the cost and reliability of the substation. For important substations

2730-474: Is necessary to work on parts of the substation while energized, but employees must maintain a safe distance of at least 3 metres (9.8 ft). The aim to reduce substation footprints comes into conflict with ease of maintenance enhanced by including gaps where employees can safely work. Underneath a substation, a mat or grid of conductors laid around 0.5 or 0.6 metres (1 ft 8 in or 2 ft 0 in) underground provides grounding . This grid, which

2835-843: Is of this function. The tallest of these is located near the Tracy power station on the shore of the Saint Lawrence River, carrying a 735kV circuit between Lanoraie and Tracy . The pylon, the largest of its kind in Canada, is 174.6 metres (572.8 ft) tall, the same height as the Montreal Olympic Stadium , and slightly larger than the Washington Monument in the United States (555 feet (169.2 m)). The pylons and conductors are designed to handle 45 millimetres (1.8 inches) of ice accumulation without failure, since Hydro-Québec raised

2940-472: Is plentiful and appearance of the station is not a factor, steel lattice towers provide low-cost supports for transmission lines and apparatus. Low-profile substations may be specified in suburban areas where appearance is more critical. Indoor substations may be gas insulated substations (GIS) (at high voltages, with gas insulated switchgear), or use metal-enclosed or metal-clad switchgear at lower voltages. Urban and suburban indoor substations may be finished on

3045-580: Is sent to Montreal and the population centres of the Northeastern United States, more than 1,200 kilometres (700 mi) away. Starting from the generation station in Newfoundland and Labrador , the power lines span a distance of 1,800 metres (6,000 ft) over the Churchill River gorge and run generally south-southwest for 203 kilometres (126 mi) as three side-by-side power lines in

3150-451: Is typically copper although it may be galvanized iron in some countries, is used to ground circuits that are being worked on to prevent accidental re-energization while workers are in contact with a de-energized circuit. Often, earth rods are driven deeper into the ground from the grounding grid for lower resistance grounding, and may be surrounded by bentonite or marconite to further reduce resistance and ensure effective grounding for

3255-410: Is used as a protection device to interrupt fault currents automatically, and may be used to switch loads on and off, or to cut off a line when power is flowing in the 'wrong' direction. When a large fault current flows through the circuit breaker, this is detected through the use of current transformers . The magnitude of the current transformer outputs may be used to trip the circuit breaker resulting in

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3360-451: The CKAC radio station , stated that the attack had been carried out to "denounce the 'pillaging' of Quebec's resources by the United States." Electrical substation 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

3465-585: The Saint Lawrence River between Montreal and Quebec City contain 735 kV power line loops or rings. The James Bay hydroelectric dam complex contains several relatively short 735 kV power lines that send electricity to three principal substations, ordered from west to east: Radisson , Chissibi, and Lemoyne. From these substations, six 735 kV power lines traverse the vast expanses of taiga and boreal forest in clear-cut stretches of land; this shows up clearly in aerial photos. The terrain that

3570-625: The Smallwood Reservoir in Newfoundland and Labrador. It was constructed over a period of five to six years from 1966 to 1971–72 by the Churchill Falls (Labrador) Corporation (CFLCo), though generators were installed after major construction was completed. The single generation facility cost C$ 946 million to construct and produced 5,225 MW of power initially after all eleven generating units were installed. A station upgrade in 1985 raised

3675-528: The White Mountains . This 180-to-190-mile (290 to 310 km) line, projected to carry 1,200 megawatts, will bring electricity to approximately one million homes. TransÉnergie uses series compensation to alter the way electricity behaves in power transmission lines, which improves the electricity transmission efficiency. This reduces the need to construct new power lines and increases the amount of electric power sent to population centres. Series compensation

3780-599: The magnetic field of the storm caused geomagnetically induced currents (GICs) to flow as direct current through Quebec's power lines, which are normally only conducting alternating current. The insulating nature of the Canadian Shield igneous rock directed the GICs to the power lines. The conductors then forwarded this current to sensitive electrical transformers , which require a certain voltage amplitude and frequency to function properly. Although most GICs are relatively feeble,

3885-416: The microprocessor made for an exponential increase in the number of points that could be economically controlled and monitored. Today, standardized communication protocols such as DNP3 , IEC 61850 and Modbus , to list a few, are used to allow multiple intelligent electronic devices to communicate with each other and supervisory control centers. Distributed automatic control at substations is one element of

3990-486: The 735 kV power line loops in the Saint Lawrence River region. The western set heads to Montreal, where it too forms a ring of 735 kV power lines around the city, linking to other power loops in the region. This section of Hydro-Québec TransÉnergie's power grid contains 7,400 km (4,600 mi) of 735 kV AC and 450 kV DC power line. Electrical power generated from the Churchill Falls power station

4095-570: The 735 kV power line system as the technological innovation of the 20th century for Quebec. In the wake of the 1998 ice storm the Levis De-Icer was installed and began testing in 2007 and 2008. Hydro-Québec TransÉnergie's 735 kV system consists of a set of six lines running from James Bay to Montreal and a set of four lines from Churchill Falls and the Manic-Outardes power stations to Quebec City. The South Shore region of Montreal and

4200-458: 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 may be associated with HVDC converter plants, traction current , or interconnected non-synchronous networks. These stations contain power electronic devices to change

4305-706: The La Grande project, which is located on the La Grande River and on its tributaries, such as the Eastmain River , in northwestern Quebec. The La Grande project was built in two phases; the first phase lasted twelve years from 1973 to 1985 and the second phase lasted from 1985 to present time. In all, the nine hydroelectric dams there produce over 16,500 MW of electric power, with the Robert-Bourassa or La Grande-2 station generating over 5,600 MW alone. In total,

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4410-676: The North Shore as the Gulf narrows to the southwest toward the Saint Lawrence River discharge mouth. The northernmost power line then diverges from the other two to connect with Manic-Outardes power stations located on and around the Rivière aux Outardes and the Manicouagan River. As the lines near Quebec City, the northern power line rejoins the other two 735 kV power lines. The three lines, paralleled by another 735 kV power line some distance to

4515-480: The United States. 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

4620-591: The amps exceed a certain amount over a period of time. Reclosers will attempt to re-energize the circuit after a delay. If unsuccessful for a few times, the recloser will have to be manually reset by an electrical worker. Capacitor banks are used in substations to balance the lagging current draw from inductive loads (such as motors, transformers, and some industrial equipment) with their reactive load . Additional capacitor capacity may be needed if dispersed generation (such as small diesel generators, rooftop photovoltaic solar panels , or wind turbines ) are added to

4725-549: The case of the cross-rope suspension tower, the tower legs are spread apart on two different foundations. In addition, the crossbar is replaced by a series of suspension cables with three vertical insulator strings to support the three bundles, which allows this design to consume only 6.3 tonnes of steel per kilometre of line. The design is also known as the Chainette (little necklace). TransÉnergie uses two-level pylons for angle towers or structures on 735 kV power lines to change

4830-486: The collapse of one or more towers left a row of fallen pylons. Of all the pylons damaged, some 150 were pylons supporting 735 kV lines, and 200 towers carrying 315 kV, 230 kV, or 120 kV power lines collapsed as well. In a region bounded by Montreal between Saint-Hyacinthe , Saint-Jean-sur-Richelieu and Granby , dubbed the "triangle of darkness", half of the overhead power grid was out of service. Quebec ordered myriad conductors, crossarms, and wire connections to repair

4935-587: The complexity of distribution networks grew, it became economically necessary to automate supervision and control of substations from a centrally attended point, to allow overall coordination in case of emergencies and to reduce operating costs. Early efforts to remote control substations used dedicated communication wires, often run alongside power circuits. Power-line carrier , microwave radio , fiber optic cables as well as dedicated wired remote control circuits have all been applied to Supervisory Control and Data Acquisition (SCADA) for substations. The development of

5040-503: The converter station next to the Radisson substation, the HVDC line heads south and roughly parallels the six 735 kV power lines some distance to the west. It traverses the same type of terrain as the other six lines; the land is replete with lakes, wetlands, and forested rolling hills. Gradually, the power line turns to the southeast, as it crosses under several 735 kV power lines. After

5145-477: The current to back-up lines or for parallelizing circuits in case of failure. An example is the switching stations for the HVDC Inga–Shaba transmission line. A switching station may also be known as a switchyard, and these are commonly located directly adjacent to or nearby a power station . In this case the generators from the power station supply their power into the yard onto the generator bus on one side of

5250-482: The direction of the line or switch the position of the conductor bundles. Delta pylons and three-leg guyed towers are also used as angle towers; they are referred to as "penguins" by Hydro-Québec linemen . Hydro-Québec TransÉnergie uses a combination of double-circuit three-level pylons and single-circuit delta pylons to suspend electrical conductors of other voltages, such as 315 kV. The ±450 kV high-voltage direct current line in Hydro-Québec's power grid uses

5355-533: The electrical conductors and the pylons themselves. This ice coating adds an additional weight of 15 to 20 kilograms per metre of conductor (10 to 20 lb/ft). Even though the electrical wires can withstand this extra weight, when combined with the effects of wind and precipitation, these conductors may break and fall. The pylons, designed to withstand only 45 millimetres (1.8 inches) of ice accretion, buckled and collapsed into twisted heaps of mangled steel. Cascading failures occurred on several transmission lines, where

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5460-468: The entire transmission grid out of service. The collapsed power grid left six million people and the rest of Quebec without electricity for hours on a very cold night. Even though the blackout lasted around nine hours for most places, some locations were in the dark for days. This geomagnetic storm caused about C$ 10 million in damage to Hydro-Québec and tens of millions to the customers of the utility. From January 4/5 to January 10, 1998, warm moist air from

5565-416: The equipment used to monitor, control, and protect the rest of the substation equipment. It often contains protective relays, meters, breaker controls, communications, batteries, and recorders that save detailed data about substation operations, particularly when there is any unusual activity, to help reconstruct what happened after the fact. These control rooms typically are heated and air conditioned to ensure

5670-569: The expropriated Montreal Light, Heat & Power . In 1963 Hydro-Québec purchased the shares of nearly all remaining privately owned electrical utilities then operating in Quebec and undertook construction of the Manicouagan-Outardes hydroelectric complex. To transmit the complex's annual production of about 30 billion kWh over a distance of nearly 700 km (430 mi), Hydro-Québec had to innovate. Led by Jean-Jacques Archambault , it became

5775-526: The fact Quebec escaped unscathed from the Northeast Blackout of 2003 , the system has experienced damage and service interruptions from severe storms in the past. Examples include the 1982 and 1988 Quebec blackouts prior to the large 1989 and 1998 power interruptions. At 2:44 am EST on March 13, 1989, a severe geomagnetic storm , due to a coronal mass ejection from the Sun , struck Earth. Fluctuations within

5880-473: The first utility in the world to transmit electricity at 735 kV, rather than 300–400 kV which was the world standard at that time. In 1962, Hydro-Québec proceeded with the construction of the first 735 kV power line in the world. The line, stretching from the Manic-Outardes dam to the Levis substation, was brought into service on 29 November 1965. Over the next twenty years from 1965 to 1985, Quebec underwent

5985-492: The following interconnectors with systems in neighboring provinces and states: The maximum simultaneous delivery (export) for the interconnector common to New York and Ontario is 325 MW. In addition to the six 735 kV power lines that stem from the James Bay Project, a seventh power line was constructed as an 1,100 kilometres (680 mi) northward extension of an existing high-voltage direct current (HVDC) line connecting Quebec and New England . This power line expansion

6090-425: 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. A switching station is a substation without transformers and operating only at a single voltage level. Switching stations are sometimes used as collector and distribution stations. Sometimes they are used for switching

6195-482: The generating capacity to over 5,400 MW. Hydro-Québec Generation owns a 34.2% interest in CFLCo, which is the same company that constructed the generating plant. However, Hydro-Québec has rights to most of the 5,400 MW of power the station produces under a 65-year power purchase agreement , expiring in 2041. The system contains more than 34,187 kilometres (21,243 mi) of lines and 530 electrical substations . It

6300-399: 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. They are a common component of the infrastructure. There are 55,000 substations in

6405-408: The jurisdiction or company, there are safety standards with minimum required clearance between different live equipment or conductors or between live metal and the ground, which often varies with higher clearance being required for higher voltages because of the greater ability to generate flashover . To this is added the necessary space for employees to work safely and vehicles to pass. Sometimes it

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6510-409: The late 19th century. In 1903 the first long distance high-voltage transmission line in North America was built, a 50 kV line connecting a Shawinigan powerstation to Montréal, 135 km (84 mi) away. In the first half of the 20th century, the market was dominated by regional monopolies, whose service was publicly criticised. In response, in 1944 the provincial government created Hydro-Quebec from

6615-507: The late-1990s deposited up to 70 millimetres (2.8 inches) of ice. Across North America, electricity transmission systems are interconnected into wide area synchronous grids , or interconnections. Suppliers are legally required to follow reliability standards. In 2006, Quebec's transmission system was recognized by the North American Electric Reliability Corporation (NERC) as a full interconnection because it

6720-590: The lifetime of the substation. Above ground, the grounding conductors may be steel, aluminum, or copper. They must be thick enough to carry the expected current of a fault for 1-3 seconds and remain undamaged. Substation fences, typically at least 2 metres (6 ft 7 in) in height, both protect the public from electrical hazards and also protect the substation from vandalism. Internal fences can also be incorporated to protect employees from areas that are unsafe when energized. Substations generally have switching, protection and control equipment, and transformers. In

6825-411: The low-voltage side. More typical distribution substations have a switch, one transformer, and minimal facilities on the low-voltage side. In distributed generation projects such as a wind farm or photovoltaic power station , a collector substation may be required. It resembles a distribution substation although power flow is in the opposite direction, from many wind turbines or inverters up into

6930-438: The most mileage in the United States under one electrical company. NYPA has only 219 kilometres (136 mi) of 765 kV line, all of it contained in a single direct interconnector with Hydro-Québec. The 735 kV power line is said to lessen the environmental impact of power lines, as one single power line operating at this voltage carries the same amount of electric power as four 315 kV power lines, which would require

7035-416: The nature of those currents destabilized the voltage of the power grid and unbalanced current spikes erupted everywhere. Accordingly, protective measures were taken in response. To save the transformers and other electrical equipment, the power grid was taken out of commission, as circuit breakers tripped all over Quebec and shut off the power. Within less than 90 seconds, this wave of breaking circuits left

7140-565: The network began with the commissioning of the 735 kV AC power line in November 1965, as there was a need for electricity transmission over vast distances from the north to southern Quebec. Much of Quebec's population is served by a few 735 kV power lines. This contributed to the severity of the power outage following the North American ice storm of 1998 . The first hydroelectric stations in Quebec were built by private entrepreneurs in

7245-436: The newer pylons and the higher the voltage level, the larger the tower. Hydro-Québec TransÉnergie uses several different types of electricity pylons to support their 735 kV power lines. All of them are single-circuit, meaning that each pylon carries one power line with three bundles of four electrical subconductors separated by spacers, with each bundle transmitting one phase of current . The earliest type of tower used

7350-512: The north, span over the Saint Lawrence River to the South Shore region, where the lines form loops encompassing part of the Saint Lawrence River and the south shore. The loops are also connected to the ring of 735 kV power lines around Montreal and power lines running south from James Bay. Quebec's transmission system contains a variety of electrical pylons depending on era and voltage level. Older pylon designs tend to consume more material than

7455-400: The ones disabled by the storm in the electrical transmission and electric power distribution system. In all of Quebec, 24,000 poles, 4,000 transformers, and 1,000 electrical pylons were damaged or destroyed, more than 3,000 km (2,000 mi) of downed electrical wires; this cost a total of C$ 800 million to repair. With over 100 transmission lines paralyzed by the ice, Quebec fell into

7560-411: The outside so as to blend in with other buildings in the area. A compact substation is generally an outdoor substation built in a metal enclosure, in which each item of the electrical equipment is located very near to each other to create a relatively smaller footprint size of the substation. High-voltage circuit breakers are commonly used to interrupt the flow of current in substation equipment. At

7665-407: The page similarly to the way the apparatus would be laid out in the actual station. In a common design, incoming lines have a disconnect switch and a circuit breaker . In some cases, the lines will not have both, with either a switch or a circuit breaker being all that is considered necessary. A disconnect switch is used to provide isolation, since it cannot interrupt load current. A circuit breaker

7770-579: The power lines cross is for the most part not mountainous, but smooth and replete with lakes. Generally, four of the lines runs together in two pairs and the other two run solo, although the two single lines sometimes do run in a pair. Two intermediate 735 kV power lines, one in the north and one in the south, connect all six power lines along their path to southern Quebec. As the lines continue south, they diverge into two sets of three 735 kV transmission lines. The eastern set heads to Quebec City, where it connects with power lines from Churchill Falls and

7875-415: The power outage was over, Hydro-Québec made numerous upgrades to its system in order to improve the power grid. Examples include the strengthening of electrical pylons and power poles, and increasing the power supply. This was done to enable the utility to restore power more rapidly in the case of a massive ice striking Quebec again. Hydro-Québec has stated that it is better-prepared to handle an ice storm with

7980-605: The project cost over C$ 20 billion to construct. The Manic-Outardes river area in the Côte-Nord or North Shore region consists of several hydroelectric facilities located on three principal rivers, from west to east: Betsiamites River , Rivière aux Outardes , and the Manicouagan River . A single plant named Sainte-Marguerite-3 is located to the east on the Sainte-Marguerite River (Sept-Îles) . The facilities located in

8085-661: The public grid. Sometimes they are also transmission substations or collector substations if the railway network also operates its own grid and generators to supply the other stations. A mobile substation is a substation on wheels, containing a transformer, breakers and buswork mounted on a self-contained semi-trailer , meant to be pulled by a truck . They are designed to be compact for travel on public roads, and are used for temporary backup in times of natural disaster or war . Mobile substations are usually rated much lower than permanent installations, and may be built in several units to meet road travel limitations. Substation design

8190-542: The region were constructed over a period of five decades, from 1956 to 2005. The total generation capacity from these power stations is 10,500 MW. A 21-MW hydroelectric power station, the Lac-Robertson generating station on the Lower North Shore , is not connected to the main Quebec grid. Churchill Falls is a single underground generation station located on the Churchill River near the town of Churchill Falls and

8295-613: The regional power transmission system. Five to six days of freezing rain and precipitation crippled the Hydro-Québec power grid in the Montreal and South Shore regions. In an area 100 by 250 kilometres (62 by 155 miles), some 116 transmission lines were out of commission, including several major 735 kV power lines and the Quebec–New England HVDC ±450 kV line. Through successive waves of freezing precipitation, more than 75 millimetres (3.0 inches) of radial ice accumulated on

8400-411: The reliable operation of this equipment. Additional equipment is necessary to handle power surges associated with intermittent renewable energy such as dispersed generation from wind or solar. Most transformers lose between 5 and 1.5 percent of their input as heat and noise. Iron losses are no-load and constant whenever the transformer is energized, while copper and auxiliary losses are proportionate to

8505-687: The river crossing, the line enters into the Nicolet terminal near Sainte-Eulalie , northeast of Drummondville . South of the terminal, the line heads south and after a relatively short distance, it enters the Des Cantons close to Sherbrooke . Leaving the Des Cantons station, the power line crosses the Canada–US border and passes through the hilly Appalachian Mountains in the U.S. state of Vermont , reaching an elevation of about 650 metres (2,130 ft). The line then continues heading south-southeast and enters

8610-618: The same magnitude as the one of 1998. In 2004, shortly before U.S. President George W. Bush 's visit to Canada, a tower along the Quebec – New England Transmission HVDC circuit in the Eastern Townships near the Canada–US border was damaged by explosive charges detonated at its base. The CBC reported that a message, purportedly from the Résistance internationaliste and issued to the La Presse and Le Journal de Montréal newspapers and

8715-477: The segment within Quebec, while the segment within the US will be owned by Northern Pass Transmission LLC , a partnership between Northeast Utilities (75%) and NSTAR (25%). Estimated to cost US$ 1.1 billion to build, it is projected that the line will either run in existing right-of-way adjacent to the HVDC line that runs through New Hampshire, or it will connect to a right-of-way in northern New Hampshire that will run through

8820-428: The six 735 kV wires split up into two groups of three power lines each, the HVDC line follows the eastern group, and the western set diverges away. The line remains overhead until it reaches the north shore of the Saint Lawrence River near Grondines , where the 450 kV HVDC line descends into an underwater tunnel traversing the river . The power line surfaces on the south shore near Lotbinière substation. After

8925-571: The so-called smart grid . Betsiamites River The Betsiamites (also called Bersimis) is a river of Côte-Nord , Quebec , Canada, which joins the Saint Lawrence River . The 978 square kilometres (378 sq mi) Pipmuacan Reservoir , impounded by the Bersimis-1 Dam, is roughly halfway down its course. There are two hydro-electric power stations and dams on the Betsiamites, owned by Hydro-Québec : This article related to

9030-446: The south overriding cold air from the north produced an ice storm , leading to over 80 hours of freezing rain and drizzle. For days, a continuous shower of mostly freezing rain amounted to 70–110 millimetres (2.8–4.3 inches) of water equivalent of precipitation. Places like Montreal and the South Shore were especially hard hit, with 100 mm (3.9 in) of largely freezing rain falling. These heavy precipitation totals wreaked havoc on

9135-430: The square of the current. Auxiliary losses are due to running fans and pumps which is noisy when the transformer is operating at maximum capacity. To reduce noise, enclosures are often built around the transformer and can also be added after the substation is built. Oil-based transformers are often built with bunded areas to prevent the escape of flaming or leaking oil. Fire separation areas or firewalls are built around

9240-604: The standards in response to ice storms in Ottawa in December 1986 and Montreal in February 1961, which left 30 to 40 millimetres (1.2 to 1.6 inches) of ice. This has led to the belief that Hydro-Québec TransÉnergie's electrical pylons are "indestructible". Despite being more than three times higher than the Canadian standard of only 13 millimetres (0.51 inches) of ice tolerance, an ice storm in

9345-634: The state of New Hampshire , where it reaches the Comerford terminal near Monroe . Continuing southward into Massachusetts , the line reaches the Sandy Pond terminal outside of Boston in Ayer . The terminal is the southernmost extent of the HVDC line. In December 2008, Hydro-Québec , along with American utilities Northeast Utilities and NSTAR , created a joint venture to build a new HVDC line from Windsor, Quebec to Deerfield, New Hampshire . Hydro-Québec will own

9450-451: The substation must be considered, such as drainage , noise and road traffic effects. The substation site must be reasonably central to the distribution area to be served. The site must be secure from intrusion by passers-by, both to protect people from injury by electric shock or arcs, and to protect the electrical system from misoperation due to vandalism. If not owned and operated by a utility company, substations are typically occupied on

9555-454: The substation where electrical energy is being converted to heat, which indicates a problem and can cause additional damage from the high heat. Dissolved gas analysis can tell when an oil-insulated transformer needs to have the oil filtered or replace, and also detect other issues. Early electrical substations required manual switching or adjustment of equipment, and manual collection of data for load, energy consumption, and abnormal events. As

9660-465: The substation, heading to an open pit mine 142 kilometres (88 mi) the northwest. The terrain crossed by the power lines becomes hilly and mountainous south of the border. The lines reach over 800 metres (2,600 ft) in elevation before descending. The three lines continue heading south until they reach a substation on the North Shore of the Gulf of Saint Lawrence . From there on, the three lines parallel

9765-554: 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. Electrified railways also use substations, often distribution substations. 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

9870-436: The system. Capacitors can reduce the current in wires, helping stem system losses from voltage drop or enabling extra power to be sent through the conductors. Capacitors may be left on in response to constant inductive load or turned on when inductive load is increased, such as in the summer for air conditioners . The switching may be remote and can be done manually or automatically. Larger substations have control rooms for

9975-466: The time of interruption, current could be normal, too high due to excessive load, unusual due to a fault, or tripped by protective relays prior to anticipated trouble. The most common technologies to extinguish the power arc from separating the conductors in the breaker include: Reclosers are similar to breakers, and can be cheaper because they do not require separate protective relays. Often used in distribution, they often are programmed to trip when

10080-429: The transformer to stop the spread of fire. Firefighting vehicles are allowed a path to access the area. Maintenance of substations involves inspections, data collection and analysis, and routine scheduled work. Using methods such as infrared scanning and dissolved gas analysis, it can be predicted when the substation will need maintenance and predict dangers before they materialize. Infrared technology finds hot spots in

10185-707: The transmission grid. Usually for economy of construction the collector system operates around 35 kV, although some collector systems are 12 kV, 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

10290-401: 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

10395-454: The transmission system to the distribution system of an area. It is uneconomical to directly connect electricity consumers to the main transmission network, unless they use large amounts of power, so the distribution station reduces voltage to a level suitable for local distribution. The input for a distribution substation is typically at least two transmission or sub-transmission lines. Input voltage may be, for example, 115 kV, or whatever

10500-462: The two outside bundles are hung on a vertical insulator string and only the middle bundle is hung with a V-shaped insulator. Over the years, Hydro-Québec researchers engineered a new type of pylon, the V- guyed tower, which reduced materials consumption to 11.8 tonnes of steel per kilometre of power line. This type of tower also includes a variation with longer side crossbars, where all conductors are hung with

10605-826: The utility often tries to minimize downtime. Substations typically serve at least one of the following purposes: A transmission substation connects two or more transmission lines. The simplest case is where all transmission lines have the same voltage. 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. Transmission substations can range from simple to complex. A small "switching station" may be little more than

10710-456: The widespread damage of the power grid. Blackouts in some areas lasted for 33 days, and 90% of those affected by the blackout had no power for more than seven days. Although power was fully restored to all locations in Quebec by February 8, 1998, it wasn't until mid-March that the power facilities were back in service. By then, much social and economic damage had occurred, such as ruined food and deaths resulting from lack of electric heating. After

10815-462: 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

10920-474: Was a massive self-supporting delta pylon , or waist pylon, which consumed 21 tonnes of steel per kilometre of line. This type of pylon was used for the first 735 kV power line from the Manic-Outardes power stations to the load centre of Montreal. There are two significant variations of the delta pylon; one has longer side crossbars such that all three bundles of conductors are suspended on V-shaped insulators . The other has shorter side crossbars, such that

11025-409: Was completed in 1990. As a result, the direct current power line is unique because there are multiple static converter and inverter stations along the 1,480 kilometres (920 mi) long power line. It is also the first multiterminal HVDC line in the world. The ±450 kV power line can transmit about 2,000 MW of hydroelectric power to Montreal and the Northeastern United States. Beginning in

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