This document discusses various types of power semiconductor devices used as switches in power electronic systems. It describes uncontrolled switches like diodes, semi-controlled switches like thyristors (SCRs), and fully controlled switches including power transistors. For each type of switch, it provides brief details about their operating principles, characteristics, and example devices like power diodes, IGBTs, MOSFETs, GTOs. It also compares the power ratings and operating frequencies of different switch technologies.
On Load Tap Changer (OLTC) is used in "High Power Transformers" to control output voltage, when electric load on transformers get increase the output voltage get decrease due to internal voltage drop inside winding, change in tap is required to maintain output voltage. OLTC is a device which perform tap changing in High Power Transformers during On Load conditions and is powered by a motor.
On Load Tap Changer (OLTC) is used in "High Power Transformers" to control output voltage, when electric load on transformers get increase the output voltage get decrease due to internal voltage drop inside winding, change in tap is required to maintain output voltage. OLTC is a device which perform tap changing in High Power Transformers during On Load conditions and is powered by a motor.
Overview of Crystal Oscillator Circuit Working and Its Applicationelprocus
A crystal oscillator is an electronic oscillator circuit which is used for the mechanical resonance of a vibrating crystal of piezoelectric material. It will create an electrical signal with a given frequency. This frequency is commonly used to keep track of time.
Block diagram of a typical op-amp – characteristics of ideal and practical op-amp - parameters of opamp – inverting and non-inverting amplifier configurations - frequency response - circuit stability.
Overview of Crystal Oscillator Circuit Working and Its Applicationelprocus
A crystal oscillator is an electronic oscillator circuit which is used for the mechanical resonance of a vibrating crystal of piezoelectric material. It will create an electrical signal with a given frequency. This frequency is commonly used to keep track of time.
Block diagram of a typical op-amp – characteristics of ideal and practical op-amp - parameters of opamp – inverting and non-inverting amplifier configurations - frequency response - circuit stability.
This article discusses different power electronics devices that are in use like power diodes, power thyristors, power transistors, IGBT, GTO, IGCT and others. This article will give a basic view of these devices and their operations.
This is to certify that the research entitled ((Performance of sustainable Mortar using Calcined clay, fly ash, Limestone powder and reinforced with hybrid fiber)) have been conducted at our Technical Engineering College and there is No funding resource for this research from our University.
Introduction to Power Electronics, Power Diodes, Thyristors and Power Transistors. Different types of Power Converters, Applications of Power Electronics and Peripheral effects.
Explore the innovative world of trenchless pipe repair with our comprehensive guide, "The Benefits and Techniques of Trenchless Pipe Repair." This document delves into the modern methods of repairing underground pipes without the need for extensive excavation, highlighting the numerous advantages and the latest techniques used in the industry.
Learn about the cost savings, reduced environmental impact, and minimal disruption associated with trenchless technology. Discover detailed explanations of popular techniques such as pipe bursting, cured-in-place pipe (CIPP) lining, and directional drilling. Understand how these methods can be applied to various types of infrastructure, from residential plumbing to large-scale municipal systems.
Ideal for homeowners, contractors, engineers, and anyone interested in modern plumbing solutions, this guide provides valuable insights into why trenchless pipe repair is becoming the preferred choice for pipe rehabilitation. Stay informed about the latest advancements and best practices in the field.
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
Overview of the fundamental roles in Hydropower generation and the components involved in wider Electrical Engineering.
This paper presents the design and construction of hydroelectric dams from the hydrologist’s survey of the valley before construction, all aspects and involved disciplines, fluid dynamics, structural engineering, generation and mains frequency regulation to the very transmission of power through the network in the United Kingdom.
Author: Robbie Edward Sayers
Collaborators and co editors: Charlie Sims and Connor Healey.
(C) 2024 Robbie E. Sayers
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
NO1 Uk best vashikaran specialist in delhi vashikaran baba near me online vas...Amil Baba Dawood bangali
Contact with Dawood Bhai Just call on +92322-6382012 and we'll help you. We'll solve all your problems within 12 to 24 hours and with 101% guarantee and with astrology systematic. If you want to take any personal or professional advice then also you can call us on +92322-6382012 , ONLINE LOVE PROBLEM & Other all types of Daily Life Problem's.Then CALL or WHATSAPP us on +92322-6382012 and Get all these problems solutions here by Amil Baba DAWOOD BANGALI
#vashikaranspecialist #astrologer #palmistry #amliyaat #taweez #manpasandshadi #horoscope #spiritual #lovelife #lovespell #marriagespell#aamilbabainpakistan #amilbabainkarachi #powerfullblackmagicspell #kalajadumantarspecialist #realamilbaba #AmilbabainPakistan #astrologerincanada #astrologerindubai #lovespellsmaster #kalajaduspecialist #lovespellsthatwork #aamilbabainlahore#blackmagicformarriage #aamilbaba #kalajadu #kalailam #taweez #wazifaexpert #jadumantar #vashikaranspecialist #astrologer #palmistry #amliyaat #taweez #manpasandshadi #horoscope #spiritual #lovelife #lovespell #marriagespell#aamilbabainpakistan #amilbabainkarachi #powerfullblackmagicspell #kalajadumantarspecialist #realamilbaba #AmilbabainPakistan #astrologerincanada #astrologerindubai #lovespellsmaster #kalajaduspecialist #lovespellsthatwork #aamilbabainlahore #blackmagicforlove #blackmagicformarriage #aamilbaba #kalajadu #kalailam #taweez #wazifaexpert #jadumantar #vashikaranspecialist #astrologer #palmistry #amliyaat #taweez #manpasandshadi #horoscope #spiritual #lovelife #lovespell #marriagespell#aamilbabainpakistan #amilbabainkarachi #powerfullblackmagicspell #kalajadumantarspecialist #realamilbaba #AmilbabainPakistan #astrologerincanada #astrologerindubai #lovespellsmaster #kalajaduspecialist #lovespellsthatwork #aamilbabainlahore #Amilbabainuk #amilbabainspain #amilbabaindubai #Amilbabainnorway #amilbabainkrachi #amilbabainlahore #amilbabaingujranwalan #amilbabainislamabad
About
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Technical Specifications
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
Key Features
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface
• Compatible with MAFI CCR system
• Copatiable with IDM8000 CCR
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
Application
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
2. Power semiconductor devices
(Power switches)
Power switches: work-horses of PE systems.
Operates in two states:
Fully on. i.e. switch closed.
Conducting state
POWER SWITCH
SWITCH ON (fully closed)
Vin
Vswitch= 0
I
3. Fully off , i.e. switch opened.
Blocking state
Power switch never operates in linear mode.
Can be categorised into three groups:
Uncontrolled: Diode :
Semi-controlled: Thyristor (SCR).
Fully controlled: Power transistors: e.g. BJT, MOSFET, IGBT, GTO,
IGCT
SWITCH OFF (fully opened)
Vin
Vswitch= Vin
I=0
4. Photos of Power Switch
• Power Diodes
Stud type
“Hockey-puck” type
• IGBT
Module type: Full
bridge and three
phase
IGCT
Integrated with
its driver
5. Power Diode
When diode is forward biased, it conducts current with a small forward voltage
(Vf) across it (0.2-3V)
When reversed (or blocking state), a negligibly small leakage current (uA to
mA) flows until the reverse breakdown occurs.
Diode should not be operated at reverse voltage greater than Vr
A (Anode)
K (Cathode)
+
Vd
_
Id
Diode: Symbol
Id
VdVf
Vr
v-i characteristics
6. Reverse Recovery
When a diode is switched quickly from forward to
reverse bias, it continues to conduct due to the
minority carriers which remains in the p-n junction.
The minority carriers require finite time, i.e, trr (reverse
recovery time) to recombine with opposite charge and
neutralise.
Effects of reverse recovery are increase in switching
losses, increase in voltage rating, over-voltage (spikes)
in inductive loads
IF
IRM
VR
t0
t2
trr= ( t2 - t0 )
VRM
7. Types of Power Diodes
Line frequency (general purpose):
On state voltage: very low (below 1V)
Large trr (about 25us) (very slow response)
Very high current ratings (up to 5kA)
Very high voltage ratings(5kV)
Used in line-frequency (50/60Hz) applications
such as rectifiers
Fast recovery
Very low trr (<1us).
Power levels at several hundred volts and
several hundred amps
Normally used in high frequency circuits
8. Schottky
Very low forward voltage drop (typical 0.3V)
Limited blocking voltage (50-100V)
Used in low voltage, high current application such as switched
mode power supplies.
9. Thyristor (SCR)
If the forward breakover voltage (Vbo) is exceeded, the SCR “self-triggers”
into the conducting state
A (Anode)
K (Cathode)
+
Vak
_
Ia
Thyristor: Symbol
G (Gate)
Ig
Ia
Vak
Vr
Ig=0Ig>0
Ih
Ibo
Vbo
10. The presence of gate current will reduce Vbo.
“Normal” conditions for thyristors to turn on:
the device is in forward blocking state (i.e Vak is positive)
a positive gate current (Ig) is applied at the gate
Once conducting, the anode current is latched. Vak collapses to
normal forward volt-drop, typically 1.5-3V.
In reverse -biased mode, the SCR behaves like a diode.
11. Thyristor Conduction
Thyristor cannot be
turned off by applying
negative gate current. It
can only be turned off if
Ia goes negative
(reverse)
+
vs
_
ig
ia
wt
vo
a
ig
wt
wt
vs
12. This happens when negative portion of the of sine-wave occurs
(natural commutation),
Another method of turning off is known as “forced
commutation”,The anode current is “diverted” to another
circuitry.
13. Types of thyristors
Phase controlled
rectifying line frequency voltage and current for ac and dc
motor drives
large voltage (up to 7kV) and current (up to 4kA) capability
low on-state voltage drop (1.5 to 3V)
Inverter grade
used in inverter and chopper
Quite fast. Can be turned-on using “force-commutation”
method.
14. Light activated
Similar to phase controlled, but triggered by pulse of light.
Normally very high power ratings
TRIAC
Dual polarity thyristors
15. Controllable switches
(power transistors)
Can be turned “ON”and “OFF” by relatively very small control signals.
Operated in SATURATION and CUT-OFF modes only.
No “linear region” operation is allowed due to excessive power loss.
In general, power transistors do not operate in latched mode.
Traditional devices: Bipolar junction transistors (BJT), Metal oxide silicon field effect transistor (
MOSFET), Insulated gate bipolar transistors (IGBT), Gate turn-off thyristors (GTO)
Emerging (new) devices: Gate controlled thyristors (GCT).
16. Bipolar Junction Transistor (BJT)
Ratings: Voltage: VCE<1000, Current: IC<400A. Switching frequency up to
5kHz. Low on-state voltage: VCE(sat) : 2-3V
+
VCE
_
IC
IB
C (collector)
B (base)
E (emitter) VCE
IB
v-i characteristics
VCE (sat)
17. Low current gain (b<10). Need high base current to obtain reasonable IC .
Expensive and complex base drive circuit. Hence not popular in new
products.
18. Metal Oxide Silicon Field Effect
Transistor (MOSFET)
+
VDS
_
ID
D (drain)
G (gate)
S (source)
+
VGS
_
ID
VDS
+
VGS
_
MOSFET: symbol
(n-channel)
v-i characteristics
19. Ratings: Voltage VDS<500V, current IDS<300A. Frequency f >100KHz.
For some low power devices (few hundred watts) may go up to
MHz range.
Turning on and off is very simple.
To turn on: VGS =+15V
To turn off: VGS =0 V and 0V to turn off.
Gate drive circuit is simple
20. MOSFET characteristics
Basically low voltage device. High voltage device are available up to 600V but
with limited current. Can be paralleled quite easily for higher current capability.
Internal (dynamic) resistance between drain and source during on state, RDS(ON), ,
limits the power handling capability of MOSFET. High losses especially for high
voltage device due to RDS(ON) .
Dominant in high frequency application (>100kHz). Biggest application is in
switched-mode power supplies.
21. Insulated Gate Bipolar Transistor (IGBT)
Combination of BJT and MOSFET characteristics.
Gate behaviour similar to MOSFET - easy to turn on and off.
Low losses like BJT due to low on-state Collector-Emitter voltage (2-3V).
IGBT: symbol
+
VCE
_
IC
C (collector)
G
(gate)
E (emitter)
+
VGE _
VCE
VGE
v-i characteristics
VCE (sat)
22. Gate turn-off thyristor (GTO)
v-i characteristics
A (Anode)
K (Cathode)
+
Vak
_
Ia
GTO: Symbol
Ig
Ia
Vak
Vr
Ig=0Ig>0
Ih
Ibo
Vbo
23. Behave like normal thyristor, but can be turned off using gate signal
However turning off is difficult. Need very large reverse gate current
(normally 1/5 of anode current).
Gate drive design is very difficult due to very large reverse gate current at
turn off.
Ratings: Highest power ratings switch: Voltage: Vak<5kV; Current: Ia<5kA.
Frequency<5KHz.
Very stiff competition:
Low end-from IGBT. High end from IGCT