DSTATCOM Solves Voltage Flicker Problems
Two major North American utilities have teamed with the Electric Power Research Institute (EPRI) and Westinghouse to develop a distribution static compensator (DSTATCOM) that tames severe voltage flicker problems and could save up to $1.2 million over traditional solutions.
BC Hydro, one of the utilities, saw the need for the technology when a lumber mill in rural Canada announced plans to install some large new equipment. BC Hydro believed the equipment would cause voltage flicker for the mill`s nearest neighbors, and potentially for all customers on the same distribution line.
American Electric Power (AEP) faced a similar problem when a rock crushing facility expanded operation. The increased load caused flicker problems for other customers on AEP`s distribution circuit.
Both utilities contacted EPRI and learned that EPRI and Westinghouse were working on DSTATCOM and were looking for prototype testing field sites. When computer simulation engineering studies at each site confirmed the suitability of each application, DSTATCOM controllers were installed.
A mobile DSTATCOM unit placed in service at the sawmill in January 1997 has proven itself. Without the compensator, the line`s voltage flicker rate typically runs 7 to 8 percent. DSTATCOM reduces the flicker to an acceptable level of 4 percent. AEP`s customer, Irving Materials, produces minerals for use in construction and agriculture at its stone crushing mills. Three crushing plants include 17 high-horsepower electric motors. Start-up of the largest crusher motors creates a momentary inrush of 1,800 kVA with a 0.28 power factor.
The conventional solution to this problem would be for AEP to construct a new distribution station. Instead, it installed DSTATCOM to protect distribution circuits from erratic load effects. DSTATCOM instantaneously adjusts the level of line compensation for changing load conditions. It provides voltage support through a shunt connection to distribution lines.
Design and installation at both sites were accomplished within one year. For technical information, contact Ashok Sundaram at EPRI at (650) 855-2304 or firstname.lastname@example.org.