Energy recovery flyback type snubber for 10kV IGCT in 7MW wind turbine systems

Author

Shirmohammadi, Siamak ; Kihyun Lee ; Yongsug Suh

Author_Institution

Dept. of Electr. Eng., SGRC, Chonbuk Nat. Univ., Jeonju, South Korea

fYear

2015

fDate

1-5 June 2015

Firstpage

107

Lastpage

114

Abstract

10kV IGCT has been recently developed and has the potential to push wind turbine systems to higher power and voltage rating. Converters employing IGCTs need snubber and OVP circuit to limit the rate of rise of current and peak over voltage across IGCT during turn on and off state respectively. The conventional RCD snubber which is used in such power converter dissipates a significant amount of power. In order to reduce the amount of energy lost by conventional RCD snubber, this paper proposes a flyback-type snubber circuit that not only meets all of the IGCTs characteristics during on and off-state but also significantly saves the power loss. Loss analysis of conventional di/dt snubber and OVP circuit is performed for the 3-level NPC type back-to-back VSC supplied from grid voltage of 6.9kV. In comparison with the conventional snubber, flyback type snubber has a fewer number of components and improved efficiency leading to a reliable and efficient wind turbine systems.

Keywords

energy conservation; snubbers; thyristor convertors; wind turbines; 3-level NPC type back-to-back VSC; IGCT; OVP circuit; RCD snubber; energy recovery flyback type snubber; grid voltage; lost energy amount; power 7 MW; power converter; power loss; power rating; voltage 10 kV; voltage 6.9 kV; voltage rating; wind turbine systems; Clamps; Inductance; Inductors; Power conversion; Snubbers; Wind turbines; 3L-NPC; Flyback-type snubber; IGCT; Medium voltage; VSC; Wind turbine;

fLanguage

English

Publisher

ieee

Conference_Titel

Power Electronics and ECCE Asia (ICPE-ECCE Asia), 2015 9th International Conference on

Conference_Location

Seoul

Type

conf

DOI

10.1109/ICPE.2015.7167773

Filename

7167773