Sylmar Converter Station
Encyclopedia
Sylmar Converter Station (34°18′39"N 118°29′21"W) is the southern converter station of the electric power transmission
line Pacific DC Intertie which transmits electricity
from the Celilo Converter Station
outside The Dalles, Oregon
to Sylmar at the northern outskirts of Los Angeles
, California
, USA. The converter station converts the 500 kV direct current
coming from the northern converter station Celilo to alternating current
at 60 Hz and 230 kV synchronized with the Los Angeles power grid. The station capacity is 3,100 megawatts.
valves. The valves were series connected in three six-pulse valve bridges for each pole. The blocking voltage
of the valves was 133 kV with a maximum current of 1,800 ampere
s, for a transmission rate of 1,440 megawatts with a symmetrical voltage of 400 kV against earth.
In 1972, after the Sylmar earthquake
, the static inverter station in Sylmar had to be reconstructed after damage to the largest part.
In 1982, the power rating of the mercury arc valve rectifiers was raised by various improvements to 1,600 megawatts.
In 1985 two six-pulse valve groups of thyristor
s were added in order to increase the voltage to 500 kV per pole for a total differential voltage of 1,000 kV
In 1989 the station was extended on the field east of the highway (called Sylmar East Converter Station), where two new 1,100 ampere, 500 kV 12-pulse thyristor converters were added in parallel with the two existing converters, giving a total transmission power of 3,100 Megawatts (3,100 Amperes at +/-500 kV
In 2004, Sylmar East station was upgraded from 1,100 MW to 3,100 MW (rededicated as the Sylmar Converter Station in 2005). The controls and older converters, including the mercury arc valves, were completely replaced (in the same valve hall) by a single pair of 3,100 MW 12-pulse converters built by ABB. The upgrade was made to eliminate the environmental risks of mercury
and to reduce the maintenance
costs of the obsolete mercury arc valves.
Electric power transmission
Electric-power transmission is the bulk transfer of electrical energy, from generating power plants to Electrical substations located near demand centers...
line Pacific DC Intertie which transmits electricity
Electricity
Electricity is a general term encompassing a variety of phenomena resulting from the presence and flow of electric charge. These include many easily recognizable phenomena, such as lightning, static electricity, and the flow of electrical current in an electrical wire...
from the Celilo Converter Station
Celilo Converter Station
The Celilo Converter Station, built in 1970 and owned and operated by the Bonneville Power Administration, is the northern terminus of the Pacific DC Intertie, near The Dalles, Oregon, in the United States.-History:...
outside The Dalles, Oregon
The Dalles, Oregon
The Dalles is the largest city and county seat of Wasco County, Oregon, United States. The name of the city comes from the French word dalle The Dalles is the largest city and county seat of Wasco County, Oregon, United States. The name of the city comes from the French word dalle The Dalles is...
to Sylmar at the northern outskirts of Los Angeles
Los Ángeles
Los Ángeles is the capital of the province of Biobío, in the commune of the same name, in Region VIII , in the center-south of Chile. It is located between the Laja and Biobío rivers. The population is 123,445 inhabitants...
, California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
, USA. The converter station converts the 500 kV direct current
Direct current
Direct current is the unidirectional flow of electric charge. Direct current is produced by such sources as batteries, thermocouples, solar cells, and commutator-type electric machines of the dynamo type. Direct current may flow in a conductor such as a wire, but can also flow through...
coming from the northern converter station Celilo to alternating current
Alternating current
In alternating current the movement of electric charge periodically reverses direction. In direct current , the flow of electric charge is only in one direction....
at 60 Hz and 230 kV synchronized with the Los Angeles power grid. The station capacity is 3,100 megawatts.
History
Originally only mercury arc rectifiers were used as static inverterInverter (electrical)
An inverter is an electrical device that converts direct current to alternating current ; the converted AC can be at any required voltage and frequency with the use of appropriate transformers, switching, and control circuits....
valves. The valves were series connected in three six-pulse valve bridges for each pole. The blocking voltage
Voltage
Voltage, otherwise known as electrical potential difference or electric tension is the difference in electric potential between two points — or the difference in electric potential energy per unit charge between two points...
of the valves was 133 kV with a maximum current of 1,800 ampere
Ampere
The ampere , often shortened to amp, is the SI unit of electric current and is one of the seven SI base units. It is named after André-Marie Ampère , French mathematician and physicist, considered the father of electrodynamics...
s, for a transmission rate of 1,440 megawatts with a symmetrical voltage of 400 kV against earth.
In 1972, after the Sylmar earthquake
Sylmar earthquake
The 1971 San Fernando earthquake struck the San Fernando Valley near Sylmar, California at 6:00:55 a.m. PST on February 9, 1971, with a magnitude of 6.6....
, the static inverter station in Sylmar had to be reconstructed after damage to the largest part.
In 1982, the power rating of the mercury arc valve rectifiers was raised by various improvements to 1,600 megawatts.
In 1985 two six-pulse valve groups of thyristor
Thyristor
A thyristor is a solid-state semiconductor device with four layers of alternating N and P-type material. They act as bistable switches, conducting when their gate receives a current trigger, and continue to conduct while they are forward biased .Some sources define silicon controlled rectifiers and...
s were added in order to increase the voltage to 500 kV per pole for a total differential voltage of 1,000 kV
In 1989 the station was extended on the field east of the highway (called Sylmar East Converter Station), where two new 1,100 ampere, 500 kV 12-pulse thyristor converters were added in parallel with the two existing converters, giving a total transmission power of 3,100 Megawatts (3,100 Amperes at +/-500 kV
In 2004, Sylmar East station was upgraded from 1,100 MW to 3,100 MW (rededicated as the Sylmar Converter Station in 2005). The controls and older converters, including the mercury arc valves, were completely replaced (in the same valve hall) by a single pair of 3,100 MW 12-pulse converters built by ABB. The upgrade was made to eliminate the environmental risks of mercury
Mercury (element)
Mercury is a chemical element with the symbol Hg and atomic number 80. It is also known as quicksilver or hydrargyrum...
and to reduce the maintenance
Maintenance, Repair and Operations
Maintenance, repair, and operations or maintenance, repair, and overhaul involves fixing any sort of mechanical or electrical device should it become out of order or broken...
costs of the obsolete mercury arc valves.
See also
- Celilo Converter StationCelilo Converter StationThe Celilo Converter Station, built in 1970 and owned and operated by the Bonneville Power Administration, is the northern terminus of the Pacific DC Intertie, near The Dalles, Oregon, in the United States.-History:...
- Pacific DC Intertie