Title :
Dynamic Analysis of a Modular Multilevel Converter Based VSC-HVDC System Incorporating Transformer Magnetisation Characteristics
Author :
Vaheeshan, J. ; Barnes, M. ; Shuttleworth, R.
Author_Institution :
Power Conversion Group, Univ. of Manchester, Manchester, UK
Abstract :
When an HVDC system is subjected to AC side short circuit faults, the transformer core might be driven to saturation at fault recovery due to flux offset. The saturation will therefore cause the flow of inrush currents. In this paper, dynamic models of a MMC based VSC-HVDC system incorporating transformer magnetisation characteristics are derived and verified. Using disturbance sensitivity functions, the impact of attenuation of inrush currents due to different locations of current sensors (of inner current controller) is investigated. It is shown that placing the current sensor at the converter side of the transformer enable the inrush currents to attenuate faster and prevents the converter from overcurrent exposure, allowing it to more successfully ride-through faults.
Keywords :
HVDC power convertors; electric current control; magnetic flux; sensitivity analysis; short-circuit currents; transformer cores; AC side short circuit fault recovery; MMC based VSC HVDC system dynamic model; current sensors; disturbance sensitivity function; flux offset; high voltage direct current system; inner current controller; inrush current flow; modular multilevel converter dynamic analysis; overcurrent exposure; transformer core; transformer magnetisation characteristics; voltage source converter; HVDC transformer; current transformer; fault ride through; inrush current; saturation;
Conference_Titel :
AC and DC Power Transmission, 11th IET International Conference on
Conference_Location :
Birmingham
Print_ISBN :
978-1-84919-982-7
DOI :
10.1049/cp.2015.0007
