Opertional and Commissioning Challenges and mitigation measures while integrating new HVDC Bipole with existing +/- 800kV HVDC Bipole with DMR system

The integration of a new HVDC ±800kV bipole system with an existing 800 kV infrastructure involves numerous complex design, commissioning, and operation challenges, particularly when utilizing a common Dedicated Metallic Return (DMR) scheme. A critical aspect of this process is managing the energization of parallel poles, both with and without a pre-charge mechanism. This paper presents a practical approach to the controlled charging of parallel poles under both scenarios.