# Multi-terminal HVDC and power flow analysis

Contributor: Norwegian University of Science and Technology NTNU, Department of Electric Power Engineering

Department-Institute: Universidad Carlos III de Madrid. Departamento de Ciencia e Ingeniería de Materiales e Ingeniería Química

Degree: Ingeniería Industrial

Issued date: 2011-12

Defense date: 2012-10-31

Keywords: Sistemas eléctricos , Electrónica de potencia , Energía eólica , MATLAB Programa de aplicación

Abstract:The aim of this Specialization Project is to implement and demonstrate a general AC-DCpower flow solution in the Matlab environment. This task is interesting from the point of viewof the increasing development of the integration of offshore wind power, espThe aim of this Specialization Project is to implement and demonstrate a general AC-DCpower flow solution in the Matlab environment. This task is interesting from the point of viewof the increasing development of the integration of offshore wind power, especially in theNorth Sea area.The solution proposed in this paper, is valid for systems consisting on one DC grid, each ofits buses is connected to different AC grids. Specifically, this study focuses on a general DCgrid of three nodes and three consequent AC grids.In this project, a complete procedure on how to set-up the power flow model is developedand described. The first step taken in this process consists on the calculation of the powerflows of all the AC grids, in a sequential way. In addition to the calculation of all the involvedAC systems, the DC power flow has to be solved as well. The calculations of both powerflows, AC and DC, have been implemented using the Newton-Raphson solution algorithm. Akey challenge in this procedure has been to model the connection between the AC and DCgrid through the HVDC converters. Several possibilities have been studied, mainlydepending on the type of bus in question. A study and comparison between a converter withor without losses have been done as well.The final achievements of this Specialization Project consist on a Matlab code solvingsuccessfully this matter, highlighting that it is programmed in a general format, so that itenables modifications on the previous explained configuration between the DC and ACconnection by simple changes. This enables the future connection of more AC grids ifneeded. Additionally, it seems obvious that the election of the slack node is a criticalparameter that will influence the results; but in this work, an investigation and discussion ismade about the possibility of controlling other parameters of the grid, as for example the ACand DC power at the nodes.+-

Author: Gil Colmenero, Esther

Source: http://e-archivo.uc3m.es

## Teaser

Universidad Carlos III de Madrid Repositorio institucional e-Archivo http:--e-archivo.uc3m.es Trabajos académicos Proyectos Fin de Carrera 2011-12 Multi-terminal HVDC and power flow analysis Gil Colmenero, Esther http:--hdl.handle.net-10016-18097 Descargado de e-Archivo, repositorio institucional de la Universidad Carlos III de Madrid Multi-terminal HVDC and power flow analysis Esther Gil Colmenero Specialization Project of Electric Power Engineering - TET5500 Submission date: Supervisor: Co-supervisor: December 2011 Kjetil Uhlen Temesgen Haileselassie Norwegian University of Science and Technology Department of Electric Power Engineering Multi-terminal HVDC and power flow analysis Norwegian University of Science and Technology Summary The aim of this Specialization Project is to implement and demonstrate a general AC-DC power flow solution in the Matlab environment.
This task is interesting from the point of view of the increasing development of the integration of offshore wind power, especially in the North Sea area. The solution proposed in this paper, is valid for systems consisting on one DC grid, each of its buses is connected to different AC grids.
Specifically, this study focuses on a general DC grid of three nodes and three consequent AC grids. In this project, a complete procedure on how to set-up the power flow model is developed and described.
The first step taken in this process consists on the calculation of the power flows of all the AC grids, in a sequential way.
In addition to the calculation of all the involved AC systems, the DC power flow has to be solved as well.
The calculations of both power flows, AC and DC, have been implemented using the Newton-Raphson solution algorithm.
A key challenge in this procedure has been to model the connection between the AC and DC grid through the HVDC converters.
Several possibilities have been studied, mainly depending on the type of bus in question.
A study and comparison between a converter w...