2003 R&D 100 Awards

Technology: Emitter Turn-Off (ETO) Thyristor Switch

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Emitter Turn-Off (ETO) Thyristor Switch

Developers:

The Emitter Turn-Off (ETO) Thyristor Switch (pdf) is an inexpensive, high power/high speed, semiconductor switch for use in high power converters requiring elevated current and reverse voltage blocking capabilities. The ETO is a key enabling technology for Flexible AC Transmission System (FACTS) for safeguarding the nation’s electric power transmission and distribution.The ETO features a low gate drive power consumption with high reliability. The gate drive power does not vary significantly with the ETO current and switching frequency, approximately 15-25 watts.

Applications of the ETO include distributed energy resources, energy storage, FACTs, motor drives, and power system protection. The advantages of the ETO include a 5,000 A snubberless turn-off capability, low switching and conduction losses, low-cost device and circuit, ease for series and parallel operation, and built-in overcurrent protection and current sensor.