American Electric Power has chosen Siemens to modernize its HVDC back-to-back system at its 600 MW Welsh HVDC station in Titus County, Texas. Siemens will upgrade its 20-year-old system by installing new control and protection technologies, replacing the cooling, heating and ventilation, and incorporating new harmonic filters and shunt reactors. Managing harmonics will maintain power quality standards, and ensure the efficient and reliable operation of the Welsh HVDC station. This will be the first Siemens mid-life control and protection HVDC modernization in the U.S.
Both the Electric Reliability Council of Texas (ERCOT) and Southwest Power Pool grids have seen major changes in the way power is dispatched and network operation since the original Welsh facility was installed. These changes have led to increased levels of harmonics seen on the systems. Harmonics result in a disruption to the normal operation of the network that can lead to interruptions of the power supply. The new harmonic filters being supplied by Siemens will help the system operators control the increased level of harmonics and create more reliable power delivery.
The latest Siemens SIMATIC TDC controls, included as part of the modernization project, are a fully digital offering resulting in faster and more accurate operation. The controls will improve the reliability and availability of the station to facilitate power exchange between the Electric Reliability Council of Texas (ERCOT) and Southwest Power Pool networks. In addition, the new harmonic filters will allow the plant to accommodate to changes in the operation of the connected networks that have increased the level of harmonics since the plant was initially built.
Siemens installed the original HVDC classic station in 1994. The new upgrade will be fully completed by May 2017.