Power Flow of Multi-Terminal HVDC: Case Study NER Agra UHVDC System 800kV 6000MW

This paper presents a sequential algorithm for solving ac/dc load flow problem in a MT-HVDC System. The basic advantages of the algorithm used are its simplicity and flexibility when integrated into an already existing power flow package. The computation is very fast and the error accumulated is very low. The dc power flow problem is solved using both Gauss-Seidel and Newton-Raphson methods and comparative results are presented. The test cases that are used are WSCC 3-machine, 9-bus system with a 3-terminal MTHVDC network being integrated with the already existing ac system. The validity of this algorithm is justified by verifying the results in Dig SILENT Power Factory. The work is furthermore extended by modelling and evaluating power flow of a practical system in form of a case study i.e., NER-Agra HVDC link. It is world’s third multi-terminal and first UHVDC project which is designed for ± 800 kV, 6000 MW. A detailed modelling of this MT-HVDC System is done in order to analyze its power flow.