Transcript Power Semiconductor Systems I

Author: Ales Havel
E-mail: [email protected]
Phone number: 4287
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Web page: http://homen.vsb.cz/~hav278/
POWER SEMICONDUCTOR SYSTEMS I
Presentation contents

Power semiconductor devices
 Power
diode
 Thyristors
 GTO
thyristor
 IGCT thyristor
 MCT
 Power
transistors
 Bipolar
transistor (BJT)
 MOSFET
 IGBT

Main types of converters
Power diode
Single P-N junction creates a diode that has two terminals:
an anode (A) and a cathode (K).
Diode structure and symbol
Power diode

Steady State V-I Characteristic of a Diode
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.
Power diode

Transient V-I Characteristic of a Diode
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
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
Thyristor

Steady-State V-I Characteristic of a Thyristor
Thyristor

Transient V-I Characteristics of a Thyristor
Thyristor

Switching conditions:
 To
turn-on:
 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)
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
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.
Transistors
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
BJT transistor

Main principle of the BJT transistor
Collector
Base
Emitter
Switching the BJT transistor
BJT transistor

Static characteristics
Transfer
Input
Output
Reverse
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.
Depletion mode
N-Channel
Enhancement mode

P-Channel
MOSFET transistor

Switching MOSFET
MOSFET transistor

Static characteristic MOSFET
Linear
area
Saturation area
IGBT transistor

The Insulated Gate Bipolar Transistor (IGBT) is a minoritycarrier device with high input impedance and large bipolar
current-carrying capability.
Symbol and equivalent circuit model of an IGBT
IGBT tranzistor

Switching IGBT
IGBT tranzistor

Absolute maximum ratings
IGBT tranzistor

Electrical characteristic
IGBT

Thermal characteristic
IGBT




The IGBT is suitable for many applications in power electronics,
especially in Pulse Width Modulated (PWM) servo and threephase 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.
Comparison of power semiconductor
devices
Power converters

A power semiconductor converter is an electrical
device for converting electrical energy.
Thank You for your attention