This document discusses three phase controlled rectifiers. It provides information on their operation from a three phase AC supply voltage and their advantages over single phase rectifiers such as providing higher DC output voltage and power. It derives equations for the average and RMS output voltage of a three phase half wave converter with resistive or RL load. Waveforms are presented showing the output voltage at different trigger angles.
The peer-reviewed International Journal of Engineering Inventions (IJEI) is started with a mission to encourage contribution to research in Science and Technology. Encourage and motivate researchers in challenging areas of Sciences and Technology.
The peer-reviewed International Journal of Engineering Inventions (IJEI) is started with a mission to encourage contribution to research in Science and Technology. Encourage and motivate researchers in challenging areas of Sciences and Technology.
Computer Science
Active and Programmable Networks
Active safety systems
Ad Hoc & Sensor Network
Ad hoc networks for pervasive communications
Adaptive, autonomic and context-aware computing
Advance Computing technology and their application
Advanced Computing Architectures and New Programming Models
Advanced control and measurement
Aeronautical Engineering,
Agent-based middleware
Alert applications
Automotive, marine and aero-space control and all other control applications
Autonomic and self-managing middleware
Autonomous vehicle
Biochemistry
Bioinformatics
BioTechnology(Chemistry, Mathematics, Statistics, Geology)
Broadband and intelligent networks
Broadband wireless technologies
CAD/CAM/CAT/CIM
Call admission and flow/congestion control
Capacity planning and dimensioning
Changing Access to Patient Information
Channel capacity modelling and analysis
Civil Engineering,
Cloud Computing and Applications
Collaborative applications
Communication application
Communication architectures for pervasive computing
Communication systems
Computational intelligence
Computer and microprocessor-based control
Computer Architecture and Embedded Systems
Computer Business
Computer Sciences and Applications
Computer Vision
Computer-based information systems in health care
Computing Ethics
Computing Practices & Applications
Congestion and/or Flow Control
Content Distribution
Context-awareness and middleware
Creativity in Internet management and retailing
Cross-layer design and Physical layer based issue
Cryptography
Data Base Management
Data fusion
Data Mining
Data retrieval
Data Storage Management
Decision analysis methods
Decision making
Digital Economy and Digital Divide
Digital signal processing theory
Distributed Sensor Networks
Drives automation
Drug Design,
Drug Development
DSP implementation
E-Business
E-Commerce
E-Government
Electronic transceiver device for Retail Marketing Industries
Electronics Engineering,
Embeded Computer System
Emerging advances in business and its applications
Emerging signal processing areas
Enabling technologies for pervasive systems
Energy-efficient and green pervasive computing
Environmental Engineering,
Estimation and identification techniques
Evaluation techniques for middleware solutions
Event-based, publish/subscribe, and message-oriented middleware
Evolutionary computing and intelligent systems
Expert approaches
Facilities planning and management
Flexible manufacturing systems
Formal methods and tools for designing
Fuzzy algorithms
Fuzzy logics
GPS and location-based app
A novel voltage reference without the operational amplifier and resistorsIJRES Journal
novel voltage reference has been proposed and simulated using a 0.18μm CMOS process in
this paper. A near-zero temperature coefficient voltage is achieved in virtue of the bias voltage subcirciut which
consists of two MOSFETs operating in the saturation region. The kind of bias voltage subcirciut is used to
adjust the output voltage and compensate the curvature. The output voltage is equal to the extrapolated
threshold voltage of a MOSFET at absolute zero temperature, which was about 591.5 mV for the MOSFETs we
used. The power supply rejection ratio (PSRR) is improved with three feedback loops. Although the output
voltage fluctuates with process variation, the circuit can monitor the process variation in MOSFET threshold
voltage. The simulation results show that the line regulation is 0.75 mV/V in a supply voltage range from 1.6 V
to 3.1 V and the temperature coefficient is around 10.8 ppm/℃ to 28.5 ppm/℃ at 9 different corners in a
temperature range from -20℃ to 120 ℃.
The PSRR is -70 dB at 100Hz with a supply voltage at 1.8 V, and the
layout size is 0.012mm2. The results of simulation and post layout simulation are almost the same.
Three phase Nine Level Inverter with Minimum Number of Power Electronic Compo...IJMTST Journal
This paper presents a new configuration of a three-phase nine-level multilevel voltage-source inverter. This
topology constitutes three-phase two-level bridge with three bidirectional switches. A multilevel dc link using
fixed dc voltage supply and cascaded half-bridge is connected in such a way that the proposed inverter
outputs the required output voltage levels. This topology has the advantage of increasing the number of
voltage levels with reduced number of power electronic components. For the purpose of increasing the
number of voltage levels with fewer number of power electronic components, the extended structure suggests
different methods to determine the magnitudes of utilized dc voltage supplies. The proposed multi-level
inverter is designed and implemented in MATLAB/SIMULINK, and required number of voltage levels are
obtained.
PWM Switched Voltage Source Inverter with Zero Neutral Point Potentialijsrd.com
A three phase three-level pulse width modulation
(PWM) switched voltage source inverter with zero neutral
point potential is designed. It consists of three single-phase
inverter modules and each module is composed of a
switched voltage source and inverter switches. The major
advantage is that the peak value of the phase output voltage
is twice as high as that of the conventional neutral-pointclamped
PWM inverter. Thus, the proposed inverter is
suitable for applications with low voltage sources such as
batteries, fuel cells, or solar cells. Furthermore, three-level
output waveforms of the inverter can be achieved without
the switch voltage unbalance problem. Since the average
neutral point potential of the inverter is zero, a common
ground between the input stage and the output stage is
possible. Therefore, it can be applied to a transformer-less
power conditioning system. The SVS inverter is tested by a
PSIM simulation and hardware is implemented and verified.
•Designed a two stage OPAMP with a current mirror amplifier and a second CS stage along with miller compensation to provide sufficient Phase margin for stability.The circuit is also provided with temperature independent self-biased startup circuit.
•Our OPAMP exhibited a gain of 82.74dB, OVSR of 1.57V, Slew rate of 9.79V/us, Phase margin of 60 deg, GBW of 18.6 MHz, CMRR of 88.473dB, Power dissipation of 0.22mW with a 1.8V power supply.
Enhancing phase margin of ota using self biasingelelijjournal
In this paper, a new adaptive biased low voltage cascode current mirror with high input/output swing is presented. This advantage is achieved using a self-biasing transistor and compensation resistor. The new structure profits from better input dynamic range and lower supply voltage without frequency response limitation and increasing input impedance. Also, the proposed current mirror is incorporated in folded cascode amplifier in order to enhance its phase-margin. The simulation results in 0.18 μm CMOS technology confirm the theoretical analysis and exhibits 478μA linear input/output current swing and a
phase-margin enhancement of 12o for the proposed current mirror and amplifier compared to the conventional circuits, respectively
Two leg three-phase inverters (FSTPIs) have been proposed to be used in low-power; low-cost applications because of the reduced number of semiconductor devices, and space vector pulse width modulation (SVPWM) techniques have also been introduced to control FSTPIs. However, high-performance controllers are needed to implement complicated SVPWM algorithms, which limit their low-cost applications. To simplify algorithms and reduce the cost of implementation, an equivalent scalar method for SVPWM of FSTPIs is proposed. SVPWM for FSTPIs is actually a sine PWM by modulating two sine waves of 600 phase difference with a triangle wave, but in this method third harmonics doesn’t eliminated. So as to eliminate the third harmonics we have to compose a high frequency sine wave to on existing sine waves. So such a special sine PWM can be used to control FSTPIs. The Mathematical and simulation results demonstrate the validity of the proposed method.
http://www.mathworks.com/matlabcentral/fileexchange/authors/126814
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.
Computer Science
Active and Programmable Networks
Active safety systems
Ad Hoc & Sensor Network
Ad hoc networks for pervasive communications
Adaptive, autonomic and context-aware computing
Advance Computing technology and their application
Advanced Computing Architectures and New Programming Models
Advanced control and measurement
Aeronautical Engineering,
Agent-based middleware
Alert applications
Automotive, marine and aero-space control and all other control applications
Autonomic and self-managing middleware
Autonomous vehicle
Biochemistry
Bioinformatics
BioTechnology(Chemistry, Mathematics, Statistics, Geology)
Broadband and intelligent networks
Broadband wireless technologies
CAD/CAM/CAT/CIM
Call admission and flow/congestion control
Capacity planning and dimensioning
Changing Access to Patient Information
Channel capacity modelling and analysis
Civil Engineering,
Cloud Computing and Applications
Collaborative applications
Communication application
Communication architectures for pervasive computing
Communication systems
Computational intelligence
Computer and microprocessor-based control
Computer Architecture and Embedded Systems
Computer Business
Computer Sciences and Applications
Computer Vision
Computer-based information systems in health care
Computing Ethics
Computing Practices & Applications
Congestion and/or Flow Control
Content Distribution
Context-awareness and middleware
Creativity in Internet management and retailing
Cross-layer design and Physical layer based issue
Cryptography
Data Base Management
Data fusion
Data Mining
Data retrieval
Data Storage Management
Decision analysis methods
Decision making
Digital Economy and Digital Divide
Digital signal processing theory
Distributed Sensor Networks
Drives automation
Drug Design,
Drug Development
DSP implementation
E-Business
E-Commerce
E-Government
Electronic transceiver device for Retail Marketing Industries
Electronics Engineering,
Embeded Computer System
Emerging advances in business and its applications
Emerging signal processing areas
Enabling technologies for pervasive systems
Energy-efficient and green pervasive computing
Environmental Engineering,
Estimation and identification techniques
Evaluation techniques for middleware solutions
Event-based, publish/subscribe, and message-oriented middleware
Evolutionary computing and intelligent systems
Expert approaches
Facilities planning and management
Flexible manufacturing systems
Formal methods and tools for designing
Fuzzy algorithms
Fuzzy logics
GPS and location-based app
A novel voltage reference without the operational amplifier and resistorsIJRES Journal
novel voltage reference has been proposed and simulated using a 0.18μm CMOS process in
this paper. A near-zero temperature coefficient voltage is achieved in virtue of the bias voltage subcirciut which
consists of two MOSFETs operating in the saturation region. The kind of bias voltage subcirciut is used to
adjust the output voltage and compensate the curvature. The output voltage is equal to the extrapolated
threshold voltage of a MOSFET at absolute zero temperature, which was about 591.5 mV for the MOSFETs we
used. The power supply rejection ratio (PSRR) is improved with three feedback loops. Although the output
voltage fluctuates with process variation, the circuit can monitor the process variation in MOSFET threshold
voltage. The simulation results show that the line regulation is 0.75 mV/V in a supply voltage range from 1.6 V
to 3.1 V and the temperature coefficient is around 10.8 ppm/℃ to 28.5 ppm/℃ at 9 different corners in a
temperature range from -20℃ to 120 ℃.
The PSRR is -70 dB at 100Hz with a supply voltage at 1.8 V, and the
layout size is 0.012mm2. The results of simulation and post layout simulation are almost the same.
Three phase Nine Level Inverter with Minimum Number of Power Electronic Compo...IJMTST Journal
This paper presents a new configuration of a three-phase nine-level multilevel voltage-source inverter. This
topology constitutes three-phase two-level bridge with three bidirectional switches. A multilevel dc link using
fixed dc voltage supply and cascaded half-bridge is connected in such a way that the proposed inverter
outputs the required output voltage levels. This topology has the advantage of increasing the number of
voltage levels with reduced number of power electronic components. For the purpose of increasing the
number of voltage levels with fewer number of power electronic components, the extended structure suggests
different methods to determine the magnitudes of utilized dc voltage supplies. The proposed multi-level
inverter is designed and implemented in MATLAB/SIMULINK, and required number of voltage levels are
obtained.
PWM Switched Voltage Source Inverter with Zero Neutral Point Potentialijsrd.com
A three phase three-level pulse width modulation
(PWM) switched voltage source inverter with zero neutral
point potential is designed. It consists of three single-phase
inverter modules and each module is composed of a
switched voltage source and inverter switches. The major
advantage is that the peak value of the phase output voltage
is twice as high as that of the conventional neutral-pointclamped
PWM inverter. Thus, the proposed inverter is
suitable for applications with low voltage sources such as
batteries, fuel cells, or solar cells. Furthermore, three-level
output waveforms of the inverter can be achieved without
the switch voltage unbalance problem. Since the average
neutral point potential of the inverter is zero, a common
ground between the input stage and the output stage is
possible. Therefore, it can be applied to a transformer-less
power conditioning system. The SVS inverter is tested by a
PSIM simulation and hardware is implemented and verified.
•Designed a two stage OPAMP with a current mirror amplifier and a second CS stage along with miller compensation to provide sufficient Phase margin for stability.The circuit is also provided with temperature independent self-biased startup circuit.
•Our OPAMP exhibited a gain of 82.74dB, OVSR of 1.57V, Slew rate of 9.79V/us, Phase margin of 60 deg, GBW of 18.6 MHz, CMRR of 88.473dB, Power dissipation of 0.22mW with a 1.8V power supply.
Enhancing phase margin of ota using self biasingelelijjournal
In this paper, a new adaptive biased low voltage cascode current mirror with high input/output swing is presented. This advantage is achieved using a self-biasing transistor and compensation resistor. The new structure profits from better input dynamic range and lower supply voltage without frequency response limitation and increasing input impedance. Also, the proposed current mirror is incorporated in folded cascode amplifier in order to enhance its phase-margin. The simulation results in 0.18 μm CMOS technology confirm the theoretical analysis and exhibits 478μA linear input/output current swing and a
phase-margin enhancement of 12o for the proposed current mirror and amplifier compared to the conventional circuits, respectively
Two leg three-phase inverters (FSTPIs) have been proposed to be used in low-power; low-cost applications because of the reduced number of semiconductor devices, and space vector pulse width modulation (SVPWM) techniques have also been introduced to control FSTPIs. However, high-performance controllers are needed to implement complicated SVPWM algorithms, which limit their low-cost applications. To simplify algorithms and reduce the cost of implementation, an equivalent scalar method for SVPWM of FSTPIs is proposed. SVPWM for FSTPIs is actually a sine PWM by modulating two sine waves of 600 phase difference with a triangle wave, but in this method third harmonics doesn’t eliminated. So as to eliminate the third harmonics we have to compose a high frequency sine wave to on existing sine waves. So such a special sine PWM can be used to control FSTPIs. The Mathematical and simulation results demonstrate the validity of the proposed method.
http://www.mathworks.com/matlabcentral/fileexchange/authors/126814
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.
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/
Water scarcity is the lack of fresh water resources to meet the standard water demand. There are two type of water scarcity. One is physical. The other is economic water scarcity.
Automobile Management System Project Report.pdfKamal Acharya
The proposed project is developed to manage the automobile in the automobile dealer company. The main module in this project is login, automobile management, customer management, sales, complaints and reports. The first module is the login. The automobile showroom owner should login to the project for usage. The username and password are verified and if it is correct, next form opens. If the username and password are not correct, it shows the error message.
When a customer search for a automobile, if the automobile is available, they will be taken to a page that shows the details of the automobile including automobile name, automobile ID, quantity, price etc. “Automobile Management System” is useful for maintaining automobiles, customers effectively and hence helps for establishing good relation between customer and automobile organization. It contains various customized modules for effectively maintaining automobiles and stock information accurately and safely.
When the automobile is sold to the customer, stock will be reduced automatically. When a new purchase is made, stock will be increased automatically. While selecting automobiles for sale, the proposed software will automatically check for total number of available stock of that particular item, if the total stock of that particular item is less than 5, software will notify the user to purchase the particular item.
Also when the user tries to sale items which are not in stock, the system will prompt the user that the stock is not enough. Customers of this system can search for a automobile; can purchase a automobile easily by selecting fast. On the other hand the stock of automobiles can be maintained perfectly by the automobile shop manager overcoming the drawbacks of existing system.
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.
Sachpazis:Terzaghi Bearing Capacity Estimation in simple terms with Calculati...Dr.Costas Sachpazis
Terzaghi's soil bearing capacity theory, developed by Karl Terzaghi, is a fundamental principle in geotechnical engineering used to determine the bearing capacity of shallow foundations. This theory provides a method to calculate the ultimate bearing capacity of soil, which is the maximum load per unit area that the soil can support without undergoing shear failure. The Calculation HTML Code included.
Event Management System Vb Net Project Report.pdfKamal Acharya
In present era, the scopes of information technology growing with a very fast .We do not see any are untouched from this industry. The scope of information technology has become wider includes: Business and industry. Household Business, Communication, Education, Entertainment, Science, Medicine, Engineering, Distance Learning, Weather Forecasting. Carrier Searching and so on.
My project named “Event Management System” is software that store and maintained all events coordinated in college. It also helpful to print related reports. My project will help to record the events coordinated by faculties with their Name, Event subject, date & details in an efficient & effective ways.
In my system we have to make a system by which a user can record all events coordinated by a particular faculty. In our proposed system some more featured are added which differs it from the existing system such as security.
COLLEGE BUS MANAGEMENT SYSTEM PROJECT REPORT.pdfKamal Acharya
The College Bus Management system is completely developed by Visual Basic .NET Version. The application is connect with most secured database language MS SQL Server. The application is develop by using best combination of front-end and back-end languages. The application is totally design like flat user interface. This flat user interface is more attractive user interface in 2017. The application is gives more important to the system functionality. The application is to manage the student’s details, driver’s details, bus details, bus route details, bus fees details and more. The application has only one unit for admin. The admin can manage the entire application. The admin can login into the application by using username and password of the admin. The application is develop for big and small colleges. It is more user friendly for non-computer person. Even they can easily learn how to manage the application within hours. The application is more secure by the admin. The system will give an effective output for the VB.Net and SQL Server given as input to the system. The compiled java program given as input to the system, after scanning the program will generate different reports. The application generates the report for users. The admin can view and download the report of the data. The application deliver the excel format reports. Because, excel formatted reports is very easy to understand the income and expense of the college bus. This application is mainly develop for windows operating system users. In 2017, 73% of people enterprises are using windows operating system. So the application will easily install for all the windows operating system users. The application-developed size is very low. The application consumes very low space in disk. Therefore, the user can allocate very minimum local disk space for this application.
Student information management system project report ii.pdfKamal Acharya
Our project explains about the student management. This project mainly explains the various actions related to student details. This project shows some ease in adding, editing and deleting the student details. It also provides a less time consuming process for viewing, adding, editing and deleting the marks of the students.
Industrial Training at Shahjalal Fertilizer Company Limited (SFCL)MdTanvirMahtab2
This presentation is about the working procedure of Shahjalal Fertilizer Company Limited (SFCL). A Govt. owned Company of Bangladesh Chemical Industries Corporation under Ministry of Industries.
2. 2
3 Phase Controlled Rectifiers
• Operate from 3 phase ac supply voltage.
• They provide higher dc output voltage.
• Higher dc output power.
• Higher output voltage ripple frequency.
• Filtering requirements are simplified for
smoothing out load voltage and load current.
GWCET, NAGPUR
3. 3
• Extensively used in high power variable speed
industrial dc drives.
• Three single phase half-wave converters can be
connected together to form a three phase half-
wave converter.
GWCET, NAGPUR
6. 6
Vector Diagram of
3 Phase Supply Voltages
VAN
VCN
VBN
120
0
120
0
120
0 RN AN
YN BN
BN CN
v v
v v
v v
GWCET, NAGPUR
7. 7
3 Phase Supply Voltage Equations
We deifine three line to neutral voltages
(3 phase voltages) as follows
GWCET, NAGPUR
8. 8
0
0
0
sin ;
Max. Phase Voltage
2
sin
3
sin 120
2
sin
3
sin 120
sin 240
RN an m
m
YN bn m
m
BN cn m
m
m
v v V t
V
v v V t
V t
v v V t
V t
V t
GWCET, NAGPUR
11. 11
To Derive an
Expression for the
Average Output Voltage of a
3-Phase Half Wave Converter
with RL Load
for Continuous Load Current
GWCET, NAGPUR
12. 12
0
1
0
2
0
3
0
30
6
5
150
6
7
270
6
2
Each thytistor conducts for 120 or radians
3
T is triggered at t
T is triggered at t
T is triggered at t
GWCET, NAGPUR
13. 13
5
6
6
If the reference phase voltage is
sin , the average or dc output
voltage for continuous load current is calculated
using the equation
3
sin .
2
RN an m
dc m
v v V t
V V t d t
GWCET, NAGPUR
14. 14
5
6
6
5
6
6
3
sin .
2
3
cos
2
3 5
cos cos
2 6 6
m
dc
m
dc
m
dc
V
V t d t
V
V t
V
V
GWCET, NAGPUR
15. 15
0 0
0
Note from the trigonometric relationship
cos cos .cos sin .sin
5 5
cos cos sin sin
6 6
3
2
co
cos 150 cos sin 150 sin
3
2 cos 30
s .cos sin sin
6 6
.cos
m
dc
m
dc
A
V
V
B A B A B
V
V
0
sin 30 sin
GWCET, NAGPUR
16. 16
0 0
0 0 0 0
0 0
0 0
0
0
0
0
0 0
Note: cos 1
cos 180 30 cos sin 180 30 sin
3
2 cos 30 .cos sin 30 sin
cos 30 cos sin 30 sin
3
2 cos 30 .cos sin 30 s
80 30 cos 30
sin 180 30 sin 30
in
m
dc
m
dc
V
V
V
V
GWCET, NAGPUR
17. 17
0
3
2cos 30 cos
2
3 3
2 cos
2 2
3 3 3
3 cos cos
2 2
3
cos
2
Where 3 Max. line to line supply voltage
m
dc
m
dc
m m
dc
Lm
dc
Lm m
V
V
V
V
V V
V
V
V
V V
GWCET, NAGPUR
18. 18
max
The maximum average or dc output voltage is
obtained at a delay angle 0 and is given by
3 3
2
Where is the peak phase voltage.
And the normalized average output voltage is
m
dm
dc
m
d
dcn n
V
V V
V
V
V V
cos
c
dm
V
GWCET, NAGPUR
19. 19
1
5 2
6
2 2
6
1
2
The rms value of output voltage is found by
using the equation
3
sin .
2
and we obtain
1 3
3 cos2
6 8
m
O RMS
m
O RMS
V V t d t
V V
GWCET, NAGPUR
20. 20
3 Phase Half Wave
Controlled Rectifier Output Voltage
Waveforms For RL Load
at
Different Trigger Angles
GWCET, NAGPUR
28. 28
To Derive An
Expression For The Average Or
Dc Output Voltage Of A
3 Phase Half Wave Converter With
Resistive Load
Or
RL Load With FWD
GWCET, NAGPUR
29. 29
0
1
0 0
1
0
2
0 0
2
0
30
6
30 180 ;
sin
5
150
6
150 300 ;
sin 120
O an m
O bn m
T is triggered at t
T conducts from to
v v V t
T is triggered at t
T conducts from to
v v V t
GWCET, NAGPUR
30. 30
0
3
0 0
3
0
0
7
270
6
270 420 ;
sin 240
sin 120
O cn m
m
T is triggered at t
T conducts from to
v v V t
V t
GWCET, NAGPUR
31. 31
0
0
0
0
0
0
180
30
0 0
180
30
180
30
3
.
2
sin ; for 30 to 180
3
sin .
2
3
sin .
2
dc O
O an m
dc m
m
dc
V v d t
v v V t t
V V t d t
V
V t d t
GWCET, NAGPUR
32. 32
0
0
180
30
0 0
0
0
3
cos
2
3
cos180 cos 30
2
cos180 1, we get
3
1 cos 30
2
m
dc
m
dc
m
dc
V
V t
V
V
V
V
GWCET, NAGPUR
33. 33
Three Phase Semiconverters
• 3 Phase semiconverters are used in Industrial
dc drive applications upto 120kW power
output.
• Single quadrant operation is possible.
• Power factor decreases as the delay angle
increases.
• Power factor is better than that of 3 phase half
wave converter.
GWCET, NAGPUR
39. 39
0 0
1
3 phase semiconverter output ripple frequency of
output voltage is 3
The delay angle can be varied from 0 to
During the period
30 210
7
, thyristor T is forward biased
6 6
S
f
t
t
GWCET, NAGPUR
40. 40
1
1 1
If thyristor is triggered at ,
6
& conduct together and the line to line voltage
appears across the load.
7
At , becomes negative & FWD conducts.
6
The load current contin
ac
ac m
T t
T D
v
t v D
1 1
ues to flow through FWD ;
and are turned off.
m
D
T D
GWCET, NAGPUR
41. 41
1
2
1 2
If FWD is not used the would continue to
conduct until the thyristor is triggered at
5
, and Free wheeling action would
6
be accomplished through & .
If the delay angle , e
3
m
D T
T
t
T D
ach thyristor conducts
2
for and the FWD does not conduct.
3
m
D
GWCET, NAGPUR
42. 42
0
0
0
We deifine three line neutral voltages
(3 phase voltages) as follows
sin ; Max. Phase Voltage
2
sin sin 120
3
2
sin sin 120
3
sin 240
RN an m m
YN bn m m
BN cn m m
m
v v V t V
v v V t V t
v v V t V t
V t
V
is the peak phase voltage of a wye-connected source.
m
GWCET, NAGPUR
43. 43
3 sin
6
5
3 sin
6
3 sin
2
3 sin
6
RB ac an cn m
YR ba bn an m
BY cb cn bn m
RY ab an bn m
v v v v V t
v v v v V t
v v v v V t
v v v v V t
GWCET, NAGPUR
44. 44
Wave forms of 3 Phase Semiconverter
for
600
GWCET, NAGPUR
48. 48
To derive an
Expression for the
Average Output Voltage
of 3 Phase Semiconverter
for > / 3
and Discontinuous Output Voltage
GWCET, NAGPUR
49. 49
7
6
6
7
6
6
For and discontinuous output voltage:
3
the Average output voltage is found from
3
.
2
3
3 sin
2 6
dc ac
dc m
V v d t
V V t d t
GWCET, NAGPUR
50. 50
max
3 3
1 cos
2
3
1 cos
2
3 Max. value of line-to-line supply voltage
The maximum average output voltage that occurs at
a delay angle of 0 is
3 3
m
dc
mL
dc
mL m
m
dm
dc
V
V
V
V
V V
V
V V
GWCET, NAGPUR
51. 51
1
7 2
6
2
6
The normalized average output voltage is
0.5 1 cos
The rms output voltage is found from
3
.
2
dc
n
dm
ac
O rms
V
V
V
V v d t
GWCET, NAGPUR
52. 52
1
7 2
6
2 2
6
1
2
3
3 sin
2 6
3 sin 2
3
4 2
m
O rms
m
O rms
V V t d t
V V
GWCET, NAGPUR
53. 53
Average or DC Output Voltage
of a
3-Phase Semiconverter
for / 3,
and Continuous Output Voltage
GWCET, NAGPUR
54. 54
5
6
2
6 2
For , and continuous output voltage
3
3
. .
2
3 3
1 cos
2
dc ab ac
m
dc
V v d t v d t
V
V
GWCET, NAGPUR
55. 55
1
5 2
6
2
2 2
6 2
1
2
2
0.5 1 cos
RMS value of o/p voltage is calculated by using
the equation
3
. .
2
3 2
3 3 cos
4 3
dc
n
dm
ab ac
O rms
m
O rms
V
V
V
V v d t v d t
V V
GWCET, NAGPUR
56. 56
Three Phase Full Converter
• 3 Phase Fully Controlled Full Wave Bridge
Converter.
• Known as a 6-pulse converter.
• Used in industrial applications up to 120kW
output power.
• Two quadrant operation is possible.
GWCET, NAGPUR
60. 60
• The thyristors are triggered at an interval of
/ 3.
• The frequency of output ripple voltage is 6fS.
• T1 is triggered at t = (/6 + ), T6 is already
conducting when T1 is turned ON.
• During the interval (/6 + ) to (/2 + ),
T1 and T6 conduct together & the output load
voltage is equal to vab = (van – vbn)
GWCET, NAGPUR
61. 61
• T2 is triggered at t = (/2 + ), T6 turns off
naturally as it is reverse biased as soon as T2 is
triggered.
• During the interval (/2 + ) to (5/6 + ), T1
and T2 conduct together & the output load
voltage vO = vac = (van – vcn)
• Thyristors are numbered in the order in which
they are triggered.
• The thyristor triggering sequence is 12, 23,
34, 45, 56, 61, 12, 23, 34, ………
GWCET, NAGPUR
62. 62
0
0
0
We deifine three line neutral voltages
(3 phase voltages) as follows
sin ; Max. Phase Voltage
2
sin sin 120
3
2
sin sin 120
3
sin 240
RN an m m
YN bn m m
BN cn m m
m
v v V t V
v v V t V t
v v V t V t
V t
V
is the peak phase voltage of a wye-connected source.
m
GWCET, NAGPUR
63. 63
The corresponding line-to-line
supply voltages are
3 sin
6
3 sin
2
3 sin
2
RY ab an bn m
YB bc bn cn m
BR ca cn an m
v v v v V t
v v v v V t
v v v v V t
GWCET, NAGPUR
64. 64
To Derive An Expression For The
Average Output Voltage Of
3-phase Full Converter
With Highly Inductive Load
Assuming Continuous And
Constant Load Current
GWCET, NAGPUR
65. 65
2
6
6
. ;
2
3 sin
6
dc O
O dc
O ab m
V V v d t
v v V t
The output load voltage consists of 6 voltage
pulses over a period of 2 radians, Hence the
average output voltage is calculated as
GWCET, NAGPUR
66. 66
2
6
mL
max
3
3 sin .
6
3 3 3
cos cos
Where V 3 Max. line-to-line supply vo
The maximum average dc output voltage is
obtained for a delay angle
ltage
3 3
0,
3
dc m
m mL
dc
m
m m
dm
dc
V V t d t
V V
V
V
V V
V V
L
GWCET, NAGPUR
67. 67
1
2
2
2
6
The normalized average dc output voltage is
cos
The rms value of the output voltage is found from
6
.
2
dc
dcn n
dm
O
O rms
V
V V
V
V v d t
GWCET, NAGPUR
68. 68
1
2
2
2
6
1
2
2
2 2
6
1
2
6
.
2
3
3 sin .
2 6
1 3 3
3 cos2
2 4
ab
O rms
m
O rms
m
O rms
V v d t
V V t d t
V V
GWCET, NAGPUR
69. 69
Three Phase Dual Converters
• For four quadrant operation in many industrial
variable speed dc drives , 3 phase dual
converters are used.
• Used for applications up to 2 mega watt output
power level.
• Dual converter consists of two 3 phase full
converters which are connected in parallel & in
opposite directions across a common load.
GWCET, NAGPUR
73. 73
Outputs of Converters 1 & 2
• During the interval (/6 + 1) to (/2 + 1), the
line to line voltage vab appears across the
output of converter 1 and vbc appears across the
output of converter 2
GWCET, NAGPUR
74. 74
0
0
0
We deifine three line neutral voltages
(3 phase voltages) as follows
sin ;
Max. Phase Voltage
2
sin sin 120
3
2
sin sin 120
3
sin 240
RN an m
m
YN bn m m
BN cn m m
m
v v V t
V
v v V t V t
v v V t V t
V t
GWCET, NAGPUR
75. 75
The corresponding line-to-line
supply voltages are
3 sin
6
3 sin
2
3 sin
2
RY ab an bn m
YB bc bn cn m
BR ca cn an m
v v v v V t
v v v v V t
v v v v V t
GWCET, NAGPUR
76. 76
• If vO1 and vO2 are the output voltages of
converters 1 and 2 respectively, the
instantaneous voltage across the current
limiting inductor during the interval
(/6 + 1) t (/2 + 1) is given by
To obtain an Expression for the
Circulating Current
GWCET, NAGPUR
77. 77
1 2
3 sin sin
6 2
3 cos
6
The circulating current can be calculated by
using the equation
r O O ab bc
r m
r m
v v v v v
v V t t
v V t
GWCET, NAGPUR
78. 78
1
1
6
6
1
max
1
.
1
3 cos .
6
3
sin sin
6
3
t
r r
r
t
r m
r
m
r
r
m
r
r
i t v d t
L
i t V t d t
L
V
i t t
L
V
i
L
GWCET, NAGPUR
80. 80
• There are two different modes of operation.
Circulating current free
(non circulating) mode of operation
Circulating current mode of operation
GWCET, NAGPUR
81. 81
Non Circulating
Current Mode Of Operation
• In this mode of operation only one converter is
switched on at a time
• When the converter 1 is switched on,
For 1 < 900 the converter 1 operates in the
Rectification mode
Vdc is positive, Idc is positive and hence the
average load power Pdc is positive.
• Power flows from ac source to the load
GWCET, NAGPUR
82. 82
• When the converter 1 is on,
For 1 > 900 the converter 1 operates in the
Inversion mode
Vdc is negative, Idc is positive and the average
load power Pdc is negative.
• Power flows from load circuit to ac source.
GWCET, NAGPUR
83. 83
• When the converter 2 is switched on,
For 2 < 900 the converter 2 operates in the
Rectification mode
Vdc is negative, Idc is negative and the average
load power Pdc is positive.
• The output load voltage & load current reverse
when converter 2 is on.
• Power flows from ac source to the load
GWCET, NAGPUR
84. 84
• When the converter 2 is switched on,
For 2 > 900 the converter 2 operates in the
Inversion mode
Vdc is positive, Idc is negative and the average
load power Pdc is negative.
• Power flows from load to the ac source.
• Energy is supplied from the load circuit to the
ac supply.
GWCET, NAGPUR
85. 85
Circulating Current
Mode Of Operation
• Both the converters are switched on at the same
time.
• One converter operates in the rectification
mode while the other operates in the inversion
mode.
• Trigger angles 1 & 2 are adjusted such that
(1 + 2) = 1800
GWCET, NAGPUR
86. 86
• When 1 < 900, converter 1 operates as a
controlled rectifier. 2 is made greater than
900 and converter 2 operates as an Inverter.
• Vdc is positive & Idc is positive and Pdc is
positive.
GWCET, NAGPUR
87. 87
• When 2 < 900, converter 2 operates as a
controlled rectifier. 1 is made greater than
900 and converter 1 operates as an Inverter.
• Vdc is negative & Idc is negative and Pdc is
positive.
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