Power switches IGBTs

AC electric drives require more sophisticated converters when they are supplied with DC sources, because electric machines requires periodic voltage and current waves with a variable frequency depending on the load requirements. In Fig. 5.8, the scheme of an example of three-phase induction motor driven by a pulse-width-modulated inverter is reported. In this scheme a three-phase bridge connection with six power modules is shown to form the so-called inverter. Each power module can be composed by a number of power switches connected in parallel to carry higher currents. Across each power switch (IGBT) a parallel diode is connected to provide a return path for the phase current when the power module is switched off. 

There are two major types of power switches used today the bipolar power transistor (BJT) and the power MOSFET. The IGBT (integrated gate bipolar transistor) is used in the higher power industrial applications, such as 1 kW power supplies and electronic motor drives. The IBGT has a slower turn-off than does the MOSFET, so it is typically used for switching frequencies of less than 20 kHz. 

Before 1990s, thyristors and transistors were used as power modules for AC drive systems. Since then other semiconductor switching power modules have been used, such as GTO, MOSFETs, IGBTs, and combination of them. Nowadays IGBT and MCT-based inverters are used by electric drives manufacturers for the electric car market. The key characteristics of the different types of technology used for power electronic component are reported in Table 5.1. However, other power switching modules are currently under development [12]. 

Power MOSFF.Ts and IGBTs can handle much higher switching frequencies, compared o a thyristor. In an a.c. motor control, fast switching is mandatory and therefore transistors are preferred. 

This is applicable to thyristor (SCR) circuits to protect all the semiconductor devices used in the switching circuit, such as diodes (also power diodes) or IGBTs, in addition to SCRs. The same protection can be applied to all the semiconductor circuits likely to experience high dv/di. 

I m using an old Chevy 20,000 volt ignition coil pulsed by a 555 20 Hz 50% duty. This is Just talking about the HV spark. Power source is a 12 volt 8-battery bank. Switching is done by an IRG4P254S IGBT. 

For low-power applications, the devices of choice are the MOSFET, the IGBT, and the BJT. For applications up to 1 kV, the MOSFET is the device of choice because it is a voltage-control device and has a fast switching speed. For applications ranging in voltage from 1 kV up to 4 kV, the IGBT is most often used. The thyristor and the GTO are used for voltages over 4 kV. 

Jones, S., and E. Khanishian, Numerical Thermal Analysis of an Oil-Cooled Hybrid IGBT Switch Module for High-Power Inverter/Converter Applications, Eroc. of the 2003 U.S. Army Collaborative Technology Alliances Conf.—Power and Energy, April 29-May 1, 2003, pp. 149-153. 

IGBT inverter bridge consisting of power electronics device works in the switch state, and susceptible to instantaneous peak voltage, short... 

Each IGBT power converter - asynchronous traction motor group works independently from the other. In case of failure of one of the two abovementioned groups, the working one continues to operate since the failed one can be switched off In this case the tram can eventually continue to operate in degraded condition. The analyses performed in this paper are limited to the failures of the traction/breaking systems only (two traction modules and one breaking module for each tram). 

Zero-current-transition PWM converters (Hua, Leu, and Lee, 1992) Figure 10.91 shows an example of zero-current transition boost converter. This approach is useful in high power converters when insulated gate bipolar transistors (IGBTs) or bipolar transistors are used as the switching devices. 

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