Abstract
In high-power converters, the on-state characteristics of semiconductor devices dictate its efficiency performance even if the optimized topologies are adopted. This letter proposes an active-forced-commutated (AFC) bridge that employs the hybrid power devices of thyristor and insulated-gate bipolar transistor (IGBT) to operate as a voltage source converter or the building blocks of complex multistage high-voltage high-power converters. In this scheme, the thyristors are placed in the main power path that conducts for most of the fundamental period to lower the on-state losses; while the IGBT-based full-bridge (FB) chain-link is used for controlled (soft) transition and forced commutation of the main thyristor bridge, operating in short period. This stepped transition voltage also leads tominimized dv/dt exerted on the interfacing transformer. To coordinate the operation of these two parts, the FB stack is designed to operate in a concave polygon stepped transition mode for the ordered turn-on and turn-off of thyristors according to different categories of commutation events. Detailed commutation analysis for the AFC-bridge is provided in this letter; also, high-level discussions and simulation results are presented to demonstrate its potential technical merits.
Original language | English |
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Pages (from-to) | 2485-2489 |
Number of pages | 5 |
Journal | IEEE Transactions on Power Electronics |
Volume | 32 |
Issue number | 4 |
DOIs | |
Publication status | Published - 14 Nov 2016 |
Keywords
- Active forced commutation (AFC)
- controlled transition
- high efficiency
- hybrid device
- insulated-gate bipolar transistor (IGBT)
- thyristor
- voltage source converter (VSC)
- HVDC
- TRANSMISSION