We will discuss the difference between IGBT and thyristor in this post. There are many differences between IGBT and thyristor power devices. But the main difference is related to switching ON and OFF of the IGBT and thyristor.
Difference between IGBT and thyristor
There are many differences between IGBT and thyristor, but the main difference is:
The main difference between IGBT and thyristor devices is that IGBT can be switched OFF by removing gate signals, but thyristor can not be.
The other differences between IGB and Thyristor are:
- The IGBT require the continuous presence of a gate signal to keep it ON, while the thyristor requires a short-time gate signal only.
- If we remove the gate signal, then the IGBT will become OFF, but the thyristor will remain ON even after removing the gate current, providing sufficient current (called latching current) flows in the thyristor.
- The thyristor remains ON until the current in the thyristor becomes less than some minimum current. This minimum current is called holding current. The current in the thyristor reduces in the AC circuit due to the presence of zero voltage every cycle. The IGBT remains ON as long as the gate signal is present.
- IGBT require almost zero gate current. It requires a continuous voltage signal of sufficient magnitude. However the thyristor requires a high amount of gate current to make it ON, but only for a short duration.
- No switch-off control from the gate current in the case of thyristors is a major drawback of the thyristors. However, this drawback is removed in the GTO version of thyristor. However, the Gate circuit of the GTO is quite complicated. After the invention of the IGBT, The IGBT replaced the GTO.
- As IGBT can be switched OFF by removing the gate signal, so IGBT finds wide application in consumer and power electronics at low voltage.
- The thyristor has better short-circuit capability.
- The thyristor is also available in high voltage and high current ratings. So it finds application in the HVDC field.
Extra knowledge as per experience
In the company I worked for, our department supplied GTO-based equipment for electric train engines in the year around 2000. However, later, only IGBT is used in the VVFD for train control applications.
We used thyristor for HVDC and SVC equipment.
For small rating power factor correction equipment, we used Triac.
If current and voltage rating is not a limitation, then IGBT is more useful.
Mosfet is similar to IGBT functionally. But IGBT is available with better output current capability.
The connection between the low-voltage electronic circuit and the gate of the IGBT becomes simple if we use optical cables. Optical cable solves noise problems also.
I hope that you enjoyed reading the article on the difference between IGBT and thyristor.
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If you like, you can watch an experiment on the difference between IGBT and thyristor in the following video
Also, read current transformer use with open secondary.
Further, read The concept of the high-speed train engine like a bullet train.
Also, read the difference between CT and PT transformer
Further read, AC or DC which is more dangerous.
Also read, what is snubber circuit and its applications.
About the author – G K Agrawal B.Sc and B.Tech (from HBTU Kanpur), Retd. Sr DGM Design (BHEL), the inventor of patents, has lifelong industry experience in the electrical and electronics design field of R&D. He worked for BHEL. He shares his experience and knowledge on blogs and YouTube. Read the profile here.
