26.10.2016
October 2016 – Introducing ABB Semiconductors New Technology Platform for RC-IGCT
Published on: 26/10/2016
Introducing ABB Semiconductors New Technology Platform for Reverse Conducting Integrated Gate Turn-off Thyristor (RC-IGCT) in Two Voltage Levels Proving Increased Performance at High Junction Temperatures
New technology platform for Reverse Conducting Integrated Gate Turn-off Thyristor (RC-IGCT) in two voltage lev- els, 4,500 V and 6,500 V. Photo credit: ABB.com
The devices are optimised for the use in applications like industrial medium voltage drives (MVD), wind-power conversion, STATCOMs, power quality and railway interties, to name a few. The main advantages are the very low on-state losses provided by the thyristor structure, the negligible turn-on losses in the semiconductor and the high reliability of the devices.
RC-IGCT Technology
The technology supports profound changes to the gate circuit, enabling much improved turn-off currents. Additionally, the HPT IGCT cell leads to increased performance at high junction temperatures. The changes to the package led to a great reduction of the thermal resistance as well as the inherent capacity for handling surge currents. The gate circuit impedance contact was moved to the periphery of the device for a greater area consumption and the centering tolerance of the gate contact on the wafer was much improved. Thus, despite the new contact has a larger diameter, the space consumption for the gate infrastructure could be reduced instead of increased.
The behaviour of the device at low forward current and high cell voltage over the whole temperature range is important. The switching behaviour can be improved by the increase of the diode thickness. Additionally, it is particularly important for RC-IGCTs to optimise the diode thickness due to the integration of the switch and the diode on the same silicon wafer.
RC-IGCT Summary
In summary, the improvements in wafer technology such as gate circuit impedance and removing thermal bottlenecks, the IGCT performance was improved significantly without increasing the size of the IGCT part.
The new device can be applied for a wide range of applications. An example for the use of the device platform is a Static Compensator (STATCOM) using Multilevel Converter topology (MMC) covering wide range of applications like industry, utility, rail-intertie and renewable applications in the range of 100 MVAr. The device was regarded as optimal solution for this topology due to significant efficiency improvement compared to an IGBT option.