The HVDC Itaipu is a
High-voltage direct current
A high-voltage direct current (HVDC) electric power transmission system (also called a power superhighway or an electrical superhighway) uses direct current (DC) for electric power transmission, in contrast with the more common alternating curre ...
overhead line
An overhead line or overhead wire is an electrical cable that is used to transmit electrical energy to electric locomotives, trolleybuses or trams. It is known variously as:
* Overhead catenary
* Overhead contact system (OCS)
* Overhead equipmen ...
transmission system in
Brazil
Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...
from the
Itaipu hydroelectric
Hydroelectricity, or hydroelectric power, is electricity generated from hydropower (water power). Hydropower supplies one sixth of the world's electricity, almost 4500 TWh in 2020, which is more than all other renewable sources combined and ...
power plant to the region of
São Paulo
São Paulo (, ; Portuguese for 'Saint Paul') is the most populous city in Brazil, and is the capital of the state of São Paulo, the most populous and wealthiest Brazilian state, located in the country's Southeast Region. Listed by the GaWC a ...
. The project consists of two ±600 kV bipoles, each with a rated power of 3150 MW, which transmit power generated at 50 Hz from the
Paraguay
Paraguay (; ), officially the Republic of Paraguay ( es, República del Paraguay, links=no; gn, Tavakuairetã Paraguái, links=si), is a landlocked country in South America. It is bordered by Argentina to the south and southwest, Brazil to th ...
side of the Itaipu Dam (near
Foz do Iguaçu
Foz do Iguaçu (''Iguazu River Mouth'') () is the Brazilian city on the border of Iguaçu Falls. The city is the 7th largest in the state of Paraná. The city's population is approximately 258,000. It is approximately 650 km (400 mi) we ...
in
Paraná) to the Ibiúna
converter station
An HVDC converter station (or simply converter station) is a specialised type of substation which forms the terminal equipment for a high-voltage direct current (HVDC) transmission line.Arrillaga, Jos; High Voltage Direct Current Transmission, se ...
near
São Roque, São Paulo. The system was put in service in several steps between 1984 and 1987, and remains among the most important HVDC installations in the world.
When the first bipole was completed in 1985, it became the world's largest HVDC system by both power transmission capacity and voltage, titles which it would hold for 25 years until the completion, in 2010, of the ±800 kV, 6400 MW HVDC link from
Xiangjiaba Dam to
Shanghai
Shanghai (; , , Standard Mandarin pronunciation: ) is one of the four direct-administered municipalities of the People's Republic of China (PRC). The city is located on the southern estuary of the Yangtze River, with the Huangpu River flow ...
in
China
China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and ...
. It also contained important innovations in real-time control systems, being one of the first HVDC schemes to use digital control equipment using
microprocessor
A microprocessor is a computer processor where the data processing logic and control is included on a single integrated circuit, or a small number of integrated circuits. The microprocessor contains the arithmetic, logic, and control circu ...
s. Nevertheless it suffered reliability problems in its first few years of operation, with numerous converter transformer failures and one serious converter fire, although reliability is now reported to be much improved.
[Praça, A., Arakari, H., Alves, S.R., Eriksson, K., Graham, J., Biledt, G.]
Itaipu HVDC Transmission System - 10 years operational experience
V SEPOPE, Recife
That it may shine on all ( Matthew 5:15)
, image_map = Brazil Pernambuco Recife location map.svg
, mapsize = 250px
, map_caption = Location in the state of Pernambuco
, pushpin_map = Brazil#South A ...
, May 1996.
Technical description
High Voltage Direct Current (HVDC) was chosen both because this technique allows long transmission lines with little loss compared to other systems (like AC), and also allows interchange of the Paraguayan 50 Hz input and the Brazilian 60 Hz input and user grid.
Both lines operate at ±600 kV and are built as overhead lines with a length of 818 (North line) and 807 (South line) kilometers. Away from their terminal stations, the two lines are at least 10 km apart to reduce risks. Each one is designed for 3150 MW at ± 600 kV D.C. and 2625 A. The lines are 4 x 689 mm² (about 30 mm ∅)
ACSR
Aluminium conductor steel-reinforced cable (ACSR) is a type of high-capacity, high-strength stranded conductor typically used in overhead power lines. The outer strands are high-purity aluminium, chosen for its good conductivity, low weight, lo ...
The incoming supply is 500 kV AC from the 50 Hz generators at the hydro dam (Foz do Iguaçu). The outgoing power is 345 and 500 kV, 60 Hz AC into the South/Southeastern grid (Ibiúna, São Paulo).
The
converter equipment, supplied by
ABB Group
ABB Ltd. is a Swedish-Swiss multinational corporation headquartered in Zürich, Switzerland. The company was formed in 1988 when Sweden's Allmänna Svenska Elektriska Aktiebolaget (ASEA) and Switzerland's Brown, Boveri & Cie merged to create ...
, uses
thyristor
A thyristor () is a solid-state semiconductor device with four layers of alternating P- and N-type materials used for high-power applications. It acts exclusively as a bistable switch (or a latch), conducting when the gate receives a current ...
valves arranged in two, twelve-pulse bridges per pole.
In parallel with the HVDC system, two 765 kV AC lines carry power from the 60 Hz generators on the Brazilian side of the dam to the São Paulo region. At into the route, at
Ivaiporã
Ivaiporã is a municipality in the state of Paraná in the Southern Region of Brazil.
See also
*List of municipalities in Paraná
This is a list of the municipalities in the state of Paraná (PR), located in the South Region of Brazil. Paraná ...
, there is a branch into 500 kV, 60 Hz AC, delivering into the Southern grid. By introducing, in 1989 and later,
series capacitors in Ivaiporã (at of the line) and
Itaberá
Itaberá is a municipality in the state of São Paulo in Brazil. The population is 17,480 (2020 est.) in an area of 1111 km². The elevation is 651 m. This place-name comes from the Tupi language
Old Tupi, Ancient Tupi or Classical Tupi (also ...
(at ) the capacity grew from 4300 MW to 6300 MW.
[ ]
Reliability
In its first few years, the project suffered many failures of converter transformers, with six in the first year of commercial operation and twelve in the first four years. Modifications had to be made to all of the transformers on the system, and led to markedly improved performance, with no failures in years 4-10.
[
On 29 May 1989, a complete quadrivalve in converter 5 of the Foz do Iguaçu converter station was destroyed by a fire which started as a result of a water leakage from a cooling pipe. The affected converter was out of action for 14 months. Similar incidents on the Rihand–Delhi project in 1990 and the ]Sylmar Converter Station
The Sylmar Converter Station is the southern converter station of the Pacific DC Intertie, an electric power transmission line which transmits electricity from the Celilo Converter Station outside The Dalles, Oregon to Sylmar, a neighborhood in t ...
of the Pacific DC Intertie
The Pacific DC Intertie (also called Path 65) is an electric power transmission line that transmits electricity from the Pacific Northwest to the Los Angeles area using HVDC, high voltage direct current (HVDC). The line capacity is 3.1 gigawatt ...
scheme in 1993 led to CIGRÉ publishing guidelines on the design of thyristor valves in order to reduce fire risks.[Fire aspects of HVDC thyristor valves and valve halls, CIGRÉbr>Technical Brochure No. 136]
February 1999.
Electrodes
Each bipole can be operated also as monopole and is equipped with a grounding electrode. The electrode line
An electrode line is used in some high-voltage direct-current (HVDC) power transmission systems, to connect the converter stations to distant ground electrodes. Many long-distance HVDC systems use sea or ground return for the DC neutral current ...
s of both bipoles are installed on wooden poles and consist of 2 x 689 mm2 1272 MCM conductors.
The electrodes for Foz do Iguaçu Station are situated at Santa Terezinha de Itaipu at and at Alvorada do Iguaçu at and are connected to the converter station via lines of 15.5 km and 16 km length respectively.
The electrodes for San Roque Station are situated at Córrego Boa Vista at and at and are connected to the converter station via lines of 66 km and 67.2 km length respectively.
Waypoints
See also
*High-voltage direct current
A high-voltage direct current (HVDC) electric power transmission system (also called a power superhighway or an electrical superhighway) uses direct current (DC) for electric power transmission, in contrast with the more common alternating curre ...
*HVDC converter station
An HVDC converter station (or simply converter station) is a specialised type of substation which forms the terminal equipment for a high-voltage direct current (HVDC) transmission line.Arrillaga, Jos; High Voltage Direct Current Transmission, se ...
*HVDC converter An HVDC converter converts electric power from high voltage alternating current (AC) to high-voltage direct current (HVDC), or vice versa. HVDC is used as an alternative to AC for transmitting electrical energy over long distances or between AC powe ...
*Electrode line
An electrode line is used in some high-voltage direct-current (HVDC) power transmission systems, to connect the converter stations to distant ground electrodes. Many long-distance HVDC systems use sea or ground return for the DC neutral current ...
*List of HVDC projects
This is a list of notable high-voltage direct-current power transmission projects.
HVDC projects for long-distance transmission have two (or rarely, more) converter stations and a transmission line interconnecting them. Generally overhead lines ...
References
{{reflist
Electric power infrastructure in Brazil
HVDC transmission lines
1984 establishments in Brazil
Energy infrastructure completed in 1987