Enhancing wind power transfer and protection of actual Egyptian 220 kV HVAC transmission system with multi-terminal VSC-HVDC system

Transmitting power using high-voltage direct current (HVDC) systems instead of high-voltage alternating current (HVAC) ones becomes desirable for integrating remote wind farms. Nowadays, Egypt planned to increase the wind power generation in the Red Sea zone from 1400 to 4000 MW by 2022. Unfortunately, the full capacity of the existing 220 kV HVAC transmission line connecting the current wind farms with the main grid is 1500 MW only. This paper aims first to pinpoint the challenges and drawbacks of the existing AC system, including limited capacity, and service quality. Then, it provides a comprehensive, technical and economic evaluation study of upgrading the existing 220 kV HVAC transmission system to a ± 160 kV HVDC system as compared with expanding the existed system to a conventional 500 kV HVAC transmission line. Finally, a thorough investigation study is presented for the proposed multi-terminal HVDC line in conjunction with its modified protection scheme based on a detailed simulation in MATLAB. Based on a variety of fault cases, an assessment of the performance and suitability of the proposed solutions is visualized. The results ensure the ability of the proposed HVDC system to be a suitable solution for integrating the wind farms in Egypt.