Project: Plains & Eastern HVDC Clean Line
Service: LCC HVDC, Renewables
Client: Clean Line Energy Partners
Year: 2013 & currently providing on-going support
The Plains & Eastern HVDC Clean Line is a merchant-owned 700 mile 4300 MW three-terminal LCC HVDC transmission line in the USA that is planned to deliver approximately 4300 MW of wind generation in Oklahoma to a 500 MW tap in Arkansas and to a 3500 MW main inverter in Tennessee.
One of these challenges with this project was the weakness of the HVDC connection at the rectifier to the AC system. There were ~4500 MW of wind generators connected to a 4300 MW HVDC rectifier, with a very weak connection to the AC system. Numerical stability of the wind generator models in the weak system, combined with a detailed transient stability HVDC model was a challenge that we overcame and learned from. Additionally, the small tap at Arkansas presented a technical challenge to which several possible solutions were presented, including a monopolar tap (instead of bipole), as well as DC controller tuning.