Application of IGCT in High Power Rectifiers

Abstract

This paper investigates the possibility of applying IGCT(Integrated Gate Commutated Thyristor) into high current high power rectifier systems. The optimal power converter topology that fully utilizes the functionality of IGCT is proposed. The proposed power converter consists of a front-end diode rectifier and 3-level step-down dc/dc converter. As compared to 2-level operation, half the input dc voltage and twice the effective switching frequency of 3-level operation can provide a wider operation range of continuous conduction mode resulting in a higher average output current of less ripple size than 2-level case. A laboratory proto-type of 5kA, 3.1MW rectifier has been simulated and tested to confirm the feasibility of IGCT in the proposed power converter topology. The proposed solution generates a relatively smooth output dc current with less contents of high frequency harmonics, thereby avoiding the high frequency harmonic related problems found in IGBT based high current rectifiers. IGCT would play a significant role to improve the cost-effective performance and reliability in low and medium ranged high current high power rectifier systems.

High‐current variable‐voltage rectifiers: state of the art topologies

“…Apart from these topologies, GTO or IGBT + diode based current source rectifier, other variants of thyristor rectifiers and modular topologies are also proposed for high-current applications; however, currently these topologies are not actively used in the industry [1][2][3][4][5][28][29][30][31][32][33][34].…”

“…Instead of thyristor rectifiers, a multi-pulse diode rectifier followed by a DC-DC chopper is proposed in the literature [1,2,4,5,[28][29][30][31][32][33][34]. Some companies are actively producing these units [1].…”

Soft Switching Behavior of IGCT for Resonant Conversion

“…Insulated Gate Bipolar Transistor (IGBT) is usually primary technology used because of its popularity and availability. Alternative to the IGBT in the area of medium voltage high current switching can be found in the Integrated Gate-Commutated Thyristor (IGCT) type of device, a mature technology found in many applications ( [10], [11]) offering various advantages over IGBT [12], [13]. Being a thyristor-based device, conduction losses are significantly lower compared to the IGBT of the similar rating; due to the mandatory di/dt limiting inductor in the clamping circuit, turn-on losses are practically zero (zero-voltage switching) while the turn-off losses are comparable to that of IGBT.…”

IGCT Low-Current Switching—TCAD and Experimental Characterization

“…At present, IGCT is a mature technology generally used in applications involving grid interties, solid state circuit breakers [17], medium voltage rectifiers [18] and drives [19] etc. with over 1GW of installed power in various pieces of equipment [19].…”