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Power Semiconductor Systems I

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Presentation on theme: "Power Semiconductor Systems I"— Presentation transcript:

1 Power Semiconductor Systems I
Author: Ales Havel Phone number: 4287 Headquarters: E227 Web page: Power Semiconductor Systems I

2 Presentation contents
Power semiconductor devices Power diode Thyristors GTO thyristor IGCT thyristor MCT Power transistors Bipolar transistor (BJT) MOSFET IGBT Main types of converters

3 Diode structure and symbol
Power diode Single P-N junction creates a diode that has two terminals: an anode (A) and a cathode (K). Diode structure and symbol

4 Power diode Steady State V-I Characteristic of a Diode

5 Power diode Dynamic parameters
Dynamic parameters relate to fast transition from ON to OFF states Not only speed of transition between the two states is important, but also changes in the diode voltage and current during the transition should be taken into account.

6 Power diode Transient V-I Characteristic of a Diode

7 Power diode Main requirements: reverse voltage Ur as high as possible
voltage drop UF as low as possible turn-off speed as high as possible Qrr (reverse recovery charge) as low as possible

8 Thyristor Thyristor (SCR – Semiconductor Controlled Rectifier) is a controlled semiconductor device of 4-layer PNPN structure with 3 PN junctions. Thyristor schematic symbol and structure

9 Thyristor Steady-State V-I Characteristic of a Thyristor

10 Thyristor Transient V-I Characteristics of a Thyristor

11 Thyristor Switching conditions: To turn-on: To turn-off:
UA = UD > 0 (forward blocking state) Bring sufficiently high current IG into the gate To turn-off: The forward current has to stop flowing A control electrode cannot effect thyristor turn-off The IL current (latching current – min. value to turn on) The IH current (holding current – min. value to stay open)

12 GTO thyristor GTO thyristor (Gate Turn-Off thyristor) is a semiconductor device built on the same principle as traditional thyristor. The difference is in the case that the GTO could be turned of by the negative gate current. GTO Thyristor schematic symbol and structure

13 MCT thyristor MOS Controlled Thyristor (MCT) is voltage controlled fully controllable thyristor. The MCT is similar in operation with GTO thyristor, but it has voltage controlled insulated gate. It has two MOSFETs in its equivalent circuit. One is responsible for turn-on and the another is responsible for turn-off.

14 Transistors The npn BJT is a three junction device that requires a continuous current flowing into the base region to supply enough charges to allow the junctions to conduct current. Because the MOSFET and the IGBT are voltage controlled devices, they only require voltage on the gate to maintain conduction through the device. The IGBT has one junction more than the MOSFET, and this junction allows higher blocking voltage and conductivity modulation, as described below, during conduction. This additional junction in the IGBT does limit switching frequency however.

15 BJT transistor A Bipolar (Junction) Transistor (BJT) is a three-terminal electronic device constructed of doped semiconductor material and may be used in amplifying or switching applications. Bipolar transistors are so named because their operation involves both electrons and holes. The BJT has three terminals, corresponding to the three layers of semiconductor – an emitter, a base, and a collector. Schematic mark

16 BJT transistor Main principle of the BJT transistor Collector Base
Emitter Switching the BJT transistor

17 BJT transistor Static characteristics Output Transfer Input Reverse

18 MOSFET transistor A Power MOSFET is a specific type of metal oxide semiconductor field-effect transistor that has been designed to handle large amounts of power. N-Channel P-Channel Depletion mode Enhancement mode

19 MOSFET transistor Switching MOSFET

20 MOSFET transistor Static characteristic MOSFET Linear area
Saturation area

21 Symbol and equivalent circuit model of an IGBT
IGBT transistor The Insulated Gate Bipolar Transistor (IGBT) is a minority- carrier device with high input impedance and large bipolar current-carrying capability. Symbol and equivalent circuit model of an IGBT

22 IGBT tranzistor Switching IGBT

23 IGBT tranzistor Absolute maximum ratings

24 IGBT tranzistor Electrical characteristic

25 IGBT Thermal characteristic

26 IGBT The IGBT is suitable for many applications in power electronics, especially in Pulse Width Modulated (PWM) servo and three- phase drives requiring high dynamic range control and low noise. It also can be used in Uninterruptible Power Supplies (UPS), Switched-Mode Power Supplies (SMPS), and other power circuits requiring high switching repetition rates. IGBT improves dynamic performance and efficiency and reduced the level of audible noise. It is equally suitable in resonant-mode converter circuits. Optimized IGBT is available for both low conduction losses and low switching losses.

27 Comparison of power semiconductor devices

28 Power converters A power semiconductor converter is an electrical device for converting electrical energy.

29 Thank You for your attention

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