VSC-HVDC based Network Reinforcement

The recent development in semiconductor and control equipment has made HVDC transmission based on voltage-source converter (VSC-HVDC) feasible. VSC-HVDC has numerous advantages such as a controllable short-circuit current contribution, the rapid and independent control of active and reactive power, and good power quality. With these advantages VSC-HVDC can likely be used to solve constraints in transmission and distribution networks. In this thesis work, the technical characteristics of a coupling between two sub-transmission systems on 50 kV level through VSC-HVDC are investigated. The main objective of the VSC-HVDC link is to mitigate network constraints in one of these networks. Area 1 is a greenhouse area having a large penetration level of CHP-plants, and Area 2 feeds a 50 kV grid that is expected to be constrained in the nearby future. The dynamic reactive power support capability of the VSC-HVDC and the available distributed generation in Area 1 are used to solve the constraints in Area 2. It is shown how the VSC-HVDC link is used as an innovative solution to mitigate network constraints and postpone major reinforcements of the network infrastructure.High-voltage Components and Power SystemsElectrical Engineering, Mathematics and Computer Scienc