- published: 03 Oct 2012
- views: 47056
A high-voltage, direct current (HVDC) electric power transmission system (also called a power super highway or an electrical super highway) uses direct current for the bulk transmission of electrical power, in contrast with the more common alternating current (AC) systems. For long-distance transmission, HVDC systems may be less expensive and suffer lower electrical losses. For underwater power cables, HVDC avoids the heavy currents required to charge and discharge the cable capacitance each cycle. For shorter distances, the higher cost of DC conversion equipment compared to an AC system may still be justified, due to other benefits of direct current links.
HVDC allows power transmission between unsynchronized AC transmission systems. Since the power flow through an HVDC link can be controlled independently of the phase angle between source and load, it can stabilize a network against disturbances due to rapid changes in power. HVDC also allows transfer of power between grid systems running at different frequencies, such as 50 Hz and 60 Hz. This improves the stability and economy of each grid, by allowing exchange of power between incompatible networks.
This HVDC back-to-back station located between Brazil and Argentina involved considerable innovation in manufacturing and construction techniques for both transmission lines and converter station. The scheduled time to deliver was only 22 months. The first phase went into commercial operation in 1999 and the second phase in 2002. For more information, please visit: http://www.abb.com/hvdc
This section explains how valves that convert ac power to dc operate.
In 1954 the world’s first high-voltage direct current (HVDC) transmission link was delivered by ABB. A new technology was born and the inventor, Uno Lamm, became known as the “father of HVDC”. In the first half of the last century, Uno Lamm led the project to develop mercury-arc valves so that they could transmit high-voltage power over longer distances. http://new.abb.com/systems/hvdc
Alstom has created history by manufacturing the first “made in India” 800 kV HVDC convertor transformer from its world-class facility at Vadodara in Gujarat. The convertor transformer is part of Power Grid’s 3000 MW advanced UHVDC system. It meet the bulk power transfer requirement from Chhattisgarh region - a hub of Independent Power Producers of thermal power - to the load centre located in the northern region of the country, through a 1,365 km transmission line, creating an “energy highway” of clean, efficient power.
This video was created to illustrate the benefits of using high voltage direct current transmission to move renewable energy over long-distances to populated areas.
This lecture is presented by Ms. Apoorva Gupta, Asst. Professor of Biyani International Institute of Engineering and Technology. HVDC transmission system is used to transmit bulk power over a long distance without much loss of power and with great efficiency. There are three types of dc links for HVDC transmission system.
525 kV voltage (previous highest installed 320 kV) sets world record more than doubling power flow to 2600 MW (from 1000 MW) and extending range to 1500 km for more cost effective, efficient and reliable underground and subsea transmission while keeping losses to below 5 percent. Major breakthrough for applications like underground HVDC transmission, sub-sea interconnections, offshore wind integration etc. More information: http://new.abb.com/systems/high-voltage-cables/cables/525-kv-extruded-hvdc-cable-system
History of General Electric and the beginning of the age of solid state in High Voltage Direct Current. HVDC in Africa, Midwest, bidding, ACEA and ABB. About solid state valves by Siemens and ABB. 1950s-1970s. Part of the GE Family Album Series. Edison Tech Center.
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(Chorus)
(Verse 2:)
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