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In switching applications modern devices feature pulse repetition rates well into the ultrasonic-range frequencies, which are at least ten times higher than audio frequencies handled by the device when used as an analog audio amplifier. As of 2010, the IGBT was the second most widely used power transistor, after the power MOSFET.
The net result is that the turn-off switching loss of an IGBT is considerably higher than its turn-on loss. Generally, in datasheets, turn-off energy is mentioned as a measured parameter; that number has to be multiplied with the switching frequency of the intended application in order to estimate the turn-off loss.
The switching losses are proportional to the switching frequency. In a complete real-world buck converter, there is also a command circuit to regulate the output voltage or the inductor current. This circuit and the MOSFET gate controller have a power consumption, impacting the overall efficiency of the converter.
Devices vary in switching speed. Some diodes and thyristors are suited for relatively slow speed and are useful for power frequency switching and control; certain thyristors are useful at a few kilohertz. Devices such as MOSFETS and BJTs can switch at tens of kilohertz up to a few megahertz in power applications, but with decreasing power levels.
The PWM switching frequency can vary greatly depending on load and application. For example, switching only has to be done several times a minute in an electric stove; 100 or 120 Hz (double of the utility frequency ) in a lamp dimmer ; between a few kilohertz (kHz) and tens of kHz for a motor drive; and well into the tens or hundreds of kHz in ...
Reducing the drive's switching frequency (the carrier-frequency) reduces the heat generated by the IGBTs. [75] A carrier frequency of at least ten times the desired output frequency is used to establish the PWM switching intervals. A carrier frequency in the range of 2,000 to 16,000 Hz is common for LV [low voltage, under 600 Volts AC] VFDs.
High power IGBTs (here a 3300V, 1200A switch) are obtained by connecting tens of dies in parallel in a power module. Opened IGBT module; different semiconductor dies are connected via wire bonds while external connectors are connected to lead-frame structures
S. Eio., N. Shammas., “IGBT Tail Current Reduction by Current Injection,” 43rd International Universities Power Engineering Conference, Padova, Italy,1 – 4 September 2008 S. Eio., N. Shammas., “A chopper circuit with current injection technique for increasing operating frequency,” 9th International Seminar On Power Semiconductors ...