Failure Modes
Thyristor manufacturers generally specify a region of safe firing defining acceptable levels of voltage and current for a given operating temperature. The boundary of this region is partly determined by the requirement that the maximum permissible gate power (PG), specified for a given trigger pulse duration, is not exceeded.
As well as the usual failure modes due to exceeding voltage, current or power ratings, thyristors have their own particular modes of failure, including:
- Turn on di/dt — in which the rate of rise of on-state current after triggering is higher than can be supported by the spreading speed of the active conduction area (SCRs & triacs).
- Forced commutation — in which the transient peak reverse recovery current causes such a high voltage drop in the sub-cathode region that it exceeds the reverse breakdown voltage of the gate cathode diode junction (SCRs only).
- Switch on dv/dt — the thyristor can be spuriously fired without trigger from the gate if the rate of rise of voltage anode to cathode is too great.
Read more about this topic: Thyristor
Famous quotes containing the words failure and/or modes:
“Successful socialism depends on the perfectibility of man. Unless all, or nearly all, men are high-minded and clear-sighted, it is bound to be a rotten failure in any but a physical sense. Even through it is altruism, socialism means materialism. You can guarantee the things of the body to every one, but you cannot guarantee the things of the spirit to every one; you can guarantee only that the opportunity to seek them shall not be denied to any one who chooses to seek them.”
—Katharine Fullerton Gerould (1879–1944)
“In the final analysis, “style” is art. And art is nothing more or less than various modes of stylized, dehumanized representation.”
—Susan Sontag (b. 1933)