The solution lay in making the distance between the power generation plant and the load centers seem, in an electrical sense, shorter. As a result, power can be transmitted at levels considerably higher than the natural loading of the transmission lines.
The benefits of series compensation - improved system stability, increased transmission capacity, and reduced overall power losses – led to a flood of orders for both new and existing transmission installations throughout the 1950s and 1960s.
As transmission capacities rose, so did the need for higher series compensation voltages. ABB delivered the first series compensation for 500 kV the United States in 1968 and progressively reached 800 kV in Brazil in 1989.
Controllable series compensation (TCSC) was installed by ABB in the late 1990s and is also part of the FACTS family.
By the end of the 20th century, the number of ABB installations of series compensation exceeded 250, and extra-high-voltage AC transmission for distances of 1,000 kilometers or more were common.
ABB's strength in semiconductors and valve technology enabled it to develop high-power thyristors and a new AC technology in the 1970s - static var compensation (SVC). SVC was initially developed to counter the random voltage variations caused by electric arc furnaces in steel mills.
When the first SVC was delivered to a steel facility in 1972 the impact was revolutionary – voltage was stabilized, energy losses reduced, and the problem of flicker that affects consumers close to steel mills was mitigated. Development did not stop there.
In 1979 ABB launched SVC for rail applications and for extra-high-voltage transmission, and in 1996 developed a mobile SVC that utilities could transport by road and locate according to where it was needed the most.
Over the years, dynamic shunt compensation to utility customers has been the dominant part of the business. In transmission grid applications SVC is used to increase the transmission capacity and specifically to improve the transient stability.