Types of IGCT devices
IGCT device basically consists of the power semiconductor packaged in a rugged, low inductance press-pack housing with an integrated gate unit. This type of semiconductor is known for its high power density, excellent performance and virtually no aging. The device voltage rating ranges from 2.5 kV class up to 10 kV class. Turn-off current can reach up to 5 kA or even more.
Types of IGCT
There are three major variants of IGCT power semiconductors based on their blocking capability:
- Asymmetric IGCT
- Reverse conducting IGCT
- Reverse blocking IGCT
Let’s look at each of them individually.
Asymmetric IGCT
As the name says, this type of IGCT is characterized by its asymmetric blocking capability depending on voltage polarity.
In forward operation the device provides full blocking capability as known from conventional thyristors. The reverse blocking capability is limited to relatively low voltage (~ 20 V). Thus, the IGCT is typically used with antiparallel diode. Most common application is in voltage source inverters.
Reverse conducting IGCT
This variant of IGCT is similar to the asymmetric one. However, the antiparallel diode is integrated inside the IGCT. Major application is again in voltage source inverters.
Reverse conducting IGCT (RC IGCT) is available for the same voltage rating as the asymmetric type. The maximum current rating is somewhat lower than the asymmetric model which is a logical consequence of diode integration (current rating still extraordinary compared to other semiconductor technologies).
Reverse blocking IGCT
Last type is the reverse blocking IGCT. The device has full forward and full reverse blocking capability. That behavior makes the semiconductor ideally suitable for current source inverters or modern solid state circuit breakers.
Summary
Three types of IGCT devices have been briefly introduced in this blog post. For more information refer to the major manufacturers such as Hitachi Energy (former ABB Semiconductors). Also, consider purchasing our premium subscription to learn more about power electronics, VFDs and motor drive systems.
References
[1] Experience with IGCT based VFD, https://mb-drive-services.com/experience-with-igct-based-vfd/
[2] Power semiconductors – Comparison of IGBT and IGCT, https://mb-drive-services.com/power-semiconductors-comparison-of-igbt-and-igct/
[3] Hitachi Energy – Semiconductors (general), https://www.hitachienergy.com/ch/de/offering/product-and-system/semiconductors
[4] Hitachi Energy – IGCT semiconductors, https://www.hitachienergy.com/ch/de/offering/product-and-system/semiconductors/integrated-gate-commutated-thyristors-igct
