The document discusses DC-DC power conversion using choppers. It describes step-down, step-up, and buck-boost chopper circuits. Step-down choppers, also called buck converters, produce a lower output voltage than the input voltage. Step-up choppers, also called boost converters, produce a higher output voltage than the input voltage. Buck-boost choppers can produce either higher or lower output voltages depending on duty cycle. Choppers are used in applications like DC motor drives and switch-mode power supplies to efficiently convert DC voltages.
A detailed step-by-step procedure for the design of a buck converter. Different active and passive components are selected as per the requirement specified in the design problem.
A detailed step-by-step procedure for the design of a buck converter. Different active and passive components are selected as per the requirement specified in the design problem.
It is based on current transformer description
It's working and applications are present in it ,it also includes videos of it's windings and it's inrush ability of transformer, and also about instrument transformer and it's working with applications.Current transformers are used-in measuring high currents and connected with it in parallel to it
Design and Simulation of Power Factor Correction Boost Converter using Hyster...ijtsrd
Nowadays various power converters like AC DC or DC DC are widely used due to their flexible output voltage and high efficiency. But these converters take the current in the form of pulses from the utility grid so that the high Total Harmonic Distortion THD and poor Power Factor PF are the major disadvantages of these converters. Hence there is a continuous need for PF improvement and reduction of line current harmonics. The most popular topology for Active Power Factor Correction APFC is a boost converter as it draws continuous input current. This input current can be manipulated by Hysteresis control technique. The boost converter can perform this type of active power factor correction in many discontinuous and continuous modes. The design and simulation of boost converter with power factor correction in continuous conduction mode is represented by using MATLAB SIMULINK software. Yu Yu Khin | Yan Aung Oo "Design and Simulation of Power Factor Correction Boost Converter using Hysteresis Control" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-5 , August 2019, URL: https://www.ijtsrd.com/papers/ijtsrd27905.pdfPaper URL: https://www.ijtsrd.com/engineering/electrical-engineering/27905/design-and-simulation-of-power-factor-correction-boost-converter-using-hysteresis-control/yu-yu-khin
SWICTH GEAR AND PROTECTION (2170906)
DISTANCE RELAY
• There are mainly Three types of distance relay
1) Impedance Relay
2) Reactance Relay
3) Mho Relay
It is based on current transformer description
It's working and applications are present in it ,it also includes videos of it's windings and it's inrush ability of transformer, and also about instrument transformer and it's working with applications.Current transformers are used-in measuring high currents and connected with it in parallel to it
Design and Simulation of Power Factor Correction Boost Converter using Hyster...ijtsrd
Nowadays various power converters like AC DC or DC DC are widely used due to their flexible output voltage and high efficiency. But these converters take the current in the form of pulses from the utility grid so that the high Total Harmonic Distortion THD and poor Power Factor PF are the major disadvantages of these converters. Hence there is a continuous need for PF improvement and reduction of line current harmonics. The most popular topology for Active Power Factor Correction APFC is a boost converter as it draws continuous input current. This input current can be manipulated by Hysteresis control technique. The boost converter can perform this type of active power factor correction in many discontinuous and continuous modes. The design and simulation of boost converter with power factor correction in continuous conduction mode is represented by using MATLAB SIMULINK software. Yu Yu Khin | Yan Aung Oo "Design and Simulation of Power Factor Correction Boost Converter using Hysteresis Control" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-5 , August 2019, URL: https://www.ijtsrd.com/papers/ijtsrd27905.pdfPaper URL: https://www.ijtsrd.com/engineering/electrical-engineering/27905/design-and-simulation-of-power-factor-correction-boost-converter-using-hysteresis-control/yu-yu-khin
SWICTH GEAR AND PROTECTION (2170906)
DISTANCE RELAY
• There are mainly Three types of distance relay
1) Impedance Relay
2) Reactance Relay
3) Mho Relay
ER Publication,
IJETR, IJMCTR,
Journals,
International Journals,
High Impact Journals,
Monthly Journal,
Good quality Journals,
Research,
Research Papers,
Research Article,
Free Journals, Open access Journals,
erpublication.org,
Engineering Journal,
Science Journals,
Research Inventy : International Journal of Engineering and Science is published by the group of young academic and industrial researchers with 12 Issues per year. It is an online as well as print version open access journal that provides rapid publication (monthly) of articles in all areas of the subject such as: civil, mechanical, chemical, electronic and computer engineering as well as production and information technology. The Journal welcomes the submission of manuscripts that meet the general criteria of significance and scientific excellence. Papers will be published by rapid process within 20 days after acceptance and peer review process takes only 7 days. All articles published in Research Inventy will be peer-reviewed.
Research Inventy : International Journal of Engineering and Science is published by the group of young academic and industrial researchers with 12 Issues per year. It is an online as well as print version open access journal that provides rapid publication (monthly) of articles in all areas of the subject such as: civil, mechanical, chemical, electronic and computer engineering as well as production and information technology. The Journal welcomes the submission of manuscripts that meet the general criteria of significance and scientific excellence. Papers will be published by rapid process within 20 days after acceptance and peer review process takes only 7 days. All articles published in Research Inventy will be peer-reviewed.
Research Inventy : International Journal of Engineering and Science is published by the group of young academic and industrial researchers with 12 Issues per year. It is an online as well as print version open access journal that provides rapid publication (monthly) of articles in all areas of the subject such as: civil, mechanical, chemical, electronic and computer engineering as well as production and information technology. The Journal welcomes the submission of manuscripts that meet the general criteria of significance and scientific excellence. Papers will be published by rapid process within 20 days after acceptance and peer review process takes only 7 days. All articles published in Research Inventy will be peer-reviewed.
The presentation consists of the detailed explanation on the topic of Converters, specifically on the rectifiers, different types of rectifiers ( Half-wave, full-wave and bridge ) configuration. The advantages and disadvantages of rectifiers and their applications
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.
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.
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.
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.
NO1 Uk best vashikaran specialist in delhi vashikaran baba near me online vas...Amil Baba Dawood bangali
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Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
ML for identifying fraud using open blockchain data.pptx
DC-DC power processing
1. Power Electronics
EE 368 Lecture-5
These slides are compiled from the material collected from the text book and web resources:
DC to DC Power
processing DC Choppers
3. DC Choppers
A chopper is a device that converts fixed DC input to a
variable DC output voltage directly.
DC-dc converters are used to convert unregulated
dc voltage to regulated or variable dc voltage at the
output.
In other words
There are several dc-dc converter topologies,
the most common ones being buck converter,
boost converter, and buck-boost converter.
Application
Used in switch-mode dc power supplies
Used in dc motor drive.
In dc motor control applications, they are called chopper-
controlled drives
TIDA-00349 Uniquely Efficient Isolated DC/DC Converter for Ultra-
Low Power and Low Power Applications Reference Design Board
Image
4. DC Choppers
Want to change the motor
RPM
Efficient DC to DC power
conversion
Will it reduce
RPM Efficiently ?
Want to reduce intensity of light
11. Problem
Electrical Motor is a varying electrical load
• A motor needs a lot more power at startup that it does when running.
• Strip motor Winding create almost a short circuit to the source
• A series resistance is used in starter circuits at starter-up and gradually removed
when it reaches to max RPM at the load.
• Motors also draw a lot more power when it run at full load.
Solution: A variable DC power supply
12. DC Choppers
Manual in series resistance
to control current by
resducing voltages Using PWM to
control
Voltage/Current
13. DC Choppers
Need a process that convert
FIXED DC source power
efficiently into VARIABLE DC
power that is required by
the LOAD.
Answer: DC-DC choppers circuits
will perform the job.
14. DC Choppers
The chopper will produce higher voltage at the load than the input supply voltage.
Two types of DC to DC conversions:
The chopper will produce lower voltages from the input supply voltages:
Step down or BUCK CONVERTER
Step up or BOOST CONVERTER
BUCK CONVERTER
BOOST CONVERTER
BUCK-BOOST CONVERTER
The chopper will produce lower/higher voltage at the load than the supply voltage.
16. DC Choppers
Step Down Chopper with Resistive Load (Buck Converter)
V
i0
V0
Chopper
R
+
When Switch is ON, the source voltages appear across the load
When Switch is OFF zero voltages appear across the load
SW = ON Vo = Vs
SW = OFF Vo = zero
SW
Because of DC input to the switch, forced commutation is
required to turn OFF the power supply to the load
IGBT can be used as a SWITCH with forced commutation
circuitry
17. DC Choppers
Step Down Chopper with Resistive Load (Buck Converter)
Vdc
v0
V
V/R
i0
Idc
t
t
tON
T
tOFF
Switching of IGBT
ON
OFF
verage value of output or load voltage.
verage value of output or load current.
Time interval for which SCR conducts.
Time interval for which SCR is OFF.
Period of switching
dc
dc
ON
OFF
ON OFF
V A
I A
t
t
T t t
or chopping period.
1
Freq. of chopper switching or chopping freq.f
T
Circuit Analysis
18. DC Choppers
Step Down Chopper with Resistive Load (Buck Converter)
Vdc
v0
V
V/R
i0
Idc
t
t
tON
T
tOFF
Switching of IGBT
ON
OFF
Average Output Voltage
.
duty cycle
ON
dc
ON OFF
ON
dc
ON
t
V V
t t
t
V V V d
T
t
but d
t
T
Circuit Analysis
Average Output Current
19. DC Choppers
Step Down Chopper with Resistive Load (Buck Converter)
2
0
2
But during ,
Therefore RMS output voltage
1
.
.
ON
ON o
t
O
ON
O ON
O
t v V
V V dt
T
tV
V t V
T T
V d V
2
2
Output power
But
Output power
O O O
O
O
O
O
O
P V I
V
I
R
V
P
R
dV
P
R
Circuit Analysis
RMS value of output voltage:
20. DC Choppers
Step Down Chopper with Resistive Load (Buck Converter)
Vdc
v0
V
V/R
i0
Idc
t
t
tON
T
tOFF
Example:
A Chopper circuit is operating on Time Ratio Control (TRC)
at a frequency of 2 kHz on a 460 V supply. If the load
voltage is 350 volts, calculate the conduction period of the
thyristor in each cycle.
Given: Vin =460 v, Vout = 360 v, f = 2000 Hz
T = 1/f = 1/2000 = 0.5 m sec
Vout = T on/ Time period x Vin
Conduction period of thyristor
Ton = (T x Vout)/Vin
(0.5 x 350) / 460 x 1000 = 0.38 m sec
21. DC Choppers
Step Down Chopper with Resistive Load (Buck Converter)
A dc chopper has a resistive load of 20 Ω and input voltage VS = 220V.
When chopper is ON, its voltage drop is 1.5 volts and chopping
frequency is 10 kHz. If the duty cycle is 80%, determine the average
output voltage and the chopper on time.
Example:
Find:
1. Output average voltage and current
2. Output RMS voltage and current
3. Output power
22. DC Choppers
Step Down Chopper with Resistive Load
(Buck Converter)
Transistor Switch ‘on’ Period
Transistor Switch ‘off’ Period
23. DC Choppers
when the switching transistor is switched on, it is
supplying the load with current.
Initially current flow to the load is restricted as
energy is also being stored in L1, therefore the
current in the load and the charge on C1 builds up
gradually during the ‘on’ period.
Throughout the ON period, there will be a large
positive voltage on D1 cathode and so the diode will
be reverse biased and play no role during ON period
Transistor Switch ‘on’ Period
24. Transistor switched off: the energy stored in the magnetic field
around L1 is released back into the circuit.
The voltage across the inductor (the back e.m.f.) is now in reverse
polarity to the voltage across L1 during the ‘on’ period, and sufficient
stored energy is available in the collapsing magnetic field to keep
current flowing for at least part of the time when the transistor switch
is OFF.:
Transistor Switch ‘off’ Period
The back e.m.f. from L1 now causes current to flow around the circuit via the load and D1, which is now
forward biased.
Once the inductor has returned a large part of its stored energy to the circuit and the load voltage begins to
fall, the charge stored in C1 becomes the main source of current, keeping current flowing through the load
until the next ‘ON’ period begins.
The overall effect of this is that, instead of a large square wave appearing across the load, there remains
only a ripple waveform, i.e. a small amplitude, high frequency triangular wave with a DC level of
VOUT = VIN x (On time of switching waveform (tON) /time periodic of switching
waveform( T))
26. DC Choppers
STEP-UP OR BOOST CONVERTER (Circuit converts Low input voltage to High output Voltages)
• Electrical motors used in driving electric automobiles require much higher voltages,
in the region of 500V, that could be supplied by a battery alone
• Voltage keep dropping with time as it is consumed by the load over longer
period of time.
Sources:
Batteries Rectified DC from AC mains supply
DC from solar panels Fuel cells *
Dynamos DC generators.
Input Sources for boost Converter
* A fuel cell produces electricity through a chemical reaction
27. DC Choppers
Boost Converter Basic Circuit:
Same components as they were
used in Buck converter except that
their positions have been rearranged.
MOSFET or BJT can be used as
a SWITCH
Basic Principle
1. High frequency applied to the
gate of the MOSFET, it will
behave as short path.
2. With no gate pulse applied to
MOSFET it will become open
path. Behavior of an Inductor
Step-up DC Choppers
28. DC Choppers
Boost Converter
• There is virtually no current flowing in the remainder of the circuit as the combination of D1, C1
and the load represent a much higher impedance than the path directly through the heavily
conducting MOSFET.
Boost converter Operation (At Switch ON)
• At start high frequency square wave are applied to the
MOSFET gate (Virtual ON condition for the switch).
• During this time MOSFET conducts, placing a short
circuit from the right hand side of L1 to the negative
input supply terminal.
• During this period current flows between the positive
and negative supply terminals through L1, which stores
energy in its magnetic field.
29. DC Choppers
Boost Converter
Current path during the low period of the switching square
wave cycle.
As the MOSFET is rapidly turned off the sudden drop in
current causes L1 to produce a back e.m.f. in the opposite
polarity to the voltage across L1 during the on period, to
keep current flowing.
This results in two voltages, the supply voltage VIN and the back e.m.f.(VL) across L1 in series with each
other.
This higher voltage (VIN +VL), with no current path through the MOSFET will move forward through D1
and will charges up the capacitor C1
This VIN +VL w[ll both togeater will appear across the load.
This mean the output voltage is Boosted
30. DC Choppers
Boost Converter
The theoretical DC output voltage is determined by the
input voltage (VIN) divided by 1 minus the duty cycle (D)
of the switching waveform, which will be some figure
between 0 and 1 (corresponding to 0 to 100%) and
therefore can be determined using the following formula:
Vout = Vin / 1-DExample:
If the switching square wave has a period of 10µs, the input voltage is 9V and the ON is half of
the periodic time, i.e. 5µs, then the output voltage will be:
VOUT = 9/(1- 0.5) = 9/0.5 = 18V (minus output diode voltage drop)
if the duty cycle increased from 0.5 to 0.99 the output voltage produced would be:
VOUT = 9/(1- 0.99) = 9/0.01 = 900V
32. Frequency Modulation
Angle Modulation is the process in which the frequency or the phase of the
carrier varies according to the message signal.
Frequency Modulation divided into:
Amplitude Modulation
Phase shift modulation.
Time Duration or Pulse Width modulation.
Frequency Modulation is the process of varying the frequency of the carrier
signal linearly with the message signal.
Phase Modulation is the process of varying the phase of the carrier signal
linearly with the message signal.
33. Amplitude Modulation
Frequency Modulation
Amplitude modulation or AM is the method of
varying the instantaneous amplitude of carrier
signal accordingly with instantaneous
amplitude of message (subject) signal.
34. Frequency Modulation
Phase:
Phase is the position
of a point in time (an
instant) on a waveform
cycle.
Phase modulation
PM or Phase modulation
is the process of varying
the instantaneous phase
of Carrier signal
accordingly with
instantaneous amplitude
of message signal
39. Average voltages in one Cycle
%100
Period
TimeOn
CycleDuty
LHavg VDVDV 1
*In general analysis, VL is taken as zero volts for
simplicity.
Duty Cycle is
determined by:
*Average value of a
signal can be found as:
Period (T)
Duty
Cycle (D)VL
VH
On Off
0
1
( )
T
y f t dt
T
Frequency Modulation
Original formula for Vo
40. Pulse Width Modulation
There are many different ways to control the
speed of DC motors but one very simple and
easy way is to use Pulse Width Modulation.
Power Electronics vision:
Pulse width modulation is
basically a square wave
with a varying width
reference to amplitude of
the original signal.
41. 41
PWM: Pulse Width Modulation with reference
• Signal is compared to a sawtooth wave producing a pulse width
proportional to amplitude
• Reference crossing the data signal above, digital pule goes low.
• Reference crossing the data signal below, digital pule goes high.
42. LHavg VDVDV 1
Pulse Width Modulation with no reference signal
Assuming: VL is taken as zero volts for simplicity.
43. By changing the MOSFET switch turning ON
and OFF time, the stored energy in the
circuit inductor and the charge in the
capacitor iis controlled in-turn the output
average of a BUCK/ BOOST is regulated.
PWM control the output average
voltage of the BUCK/BOOST
converter
44. Design of PWM Generator:
To generate a 50 percent duty cycle, the 555 timer has to work in a-stable
mode.
By connecting diode, D1 between the trigger input and the discharge input,
the timing capacitor would charge up directly through resistor R1 only, as
resistor R2 is effectively shorted out by the diode.
The capacitor discharges as normal through resistor, R2. The previous
charging time of t1 = 0.693(R1 + R2) C is modified to take account of this
new charging circuit and is given as: 0.693(R1.C). The duty cycle is therefore
given as D = R1 / (R1 + R2). Then to generate a duty cycle of more than 50%,
resistor R1 needs to be equal to resistor R2.
PWM Generator
Ref: P.Sathya1, Dr.R.Natarajan 2
45. Applications
• Automotive applications
• Power amplifier applications
• Adaptive control applications
• Solar Battery power systems
• Consumer Electronics
• Communication Applications
Advantages
• Gives the high output voltage
• Low operating duty cycles
• Lower voltage on MOSFET
46. By combining these two regulator designs it is possible to have a regulator
circuit that can cope with a wide range of input voltages both higher or lower
than that needed by the circuit. Fortunately both buck and boost converters
use very similar components; they just need to be re-arranged, depending on
the level of the input voltage.
Buck and Boost Converters Combined
the common components of the buck and boost circuits are combined. A control
unit is added, which senses the level of input voltage, then selects the appropriate
circuit action. (Note that in the examples in this section the transistors are shown
as MOSFETs, commonly used in high frequency power converters, and the diodes
shown as Schottky types. These diodes have a low forward junction voltage when
conducting, and are able to switch at high speeds).
48. Operation as a Buck Converter
During Tr1 ‘OFF’ Period
Operation as a Buck Converter
During Tr1 ‘ON’ Period
Buck-Boost Converter
Buck Converter
Buck Converter Tr1 Tr2
Supplying source voltages to
load while storing energy in
inductor
ON OFF
Inductor become source to
provide power to the load, while
the main source is disconnected
OFF OFF
49. Buck-Boost Converter
Operation as a Boost Converter
Operation as a Boost
Converter During Tr2 ‘on’
Period
Operation as a Boost
Converter During Tr2 ‘off’
Period
Boost Converter Tr1 Tr2
Using source voltages to storing
energy in inductor
ON ON
Inductor plus the main source is
used to provide power to the
load
Vo = Vin + VL+ Vc
ON OFF
50. Type Laminated lithium-ion battery
Voltage 403.2V [1]
Nominal voltage 360V [2]
Total capacity 24 kWh [2] (16 kWh available, 67% DoD [3], 21 kWh
declared [4])
Power output Over 90 kW
EV Battery Specs
51. Introduction
Converter classification
Electric vehicle (EV) power supply systems to convert high voltage battery power to conventional 12Vdc,
24Vdc, or 28Vdc
Multi Quadrant DC-DC Converters
DC-DC converters in an EV may be classified into unidirectional and bidirectional converters
Unidirectional converters are used to supply power to various onboard loads such as
sensors, controls, entertainment and safety equipment.
Bidirectional DC-DC converters are used where regenerative braking is required.
During regenerative braking the power flows back to the voltage bus to recharge the
batteries.
52. Four Quadrant Operation of any drives or DC Motor means that the machine operates
in four quadrants. ...
A motor operates in two modes – Motoring and Braking. Amotor drive capable of
operating in both directions of rotation and of producing both motoring and regeneration
is called a Four Quadrant variable speed drive
Multi Quadrant DC-DC Converters
53. DC MOTOR FACTS
Direction of rotation of a DC Motor can be
reverse by changing supply voltage polarity.
By rotating the rotor of DC motor it produce power
54. Four Quadrant Operation of any drives or DC Motor means that the machine
operates in four quadrants.
Forward Braking
Forward motoring
Reverse motoring
Reverse braking.
Four Quadrant Operation of DC Motor
A motor operates in two modes –Motoring and Braking. A motor drive capable of operating in
both directions of rotation and of producing both motoring and regeneration is called a Four
Quadrant variable speed drive.
55. According to direction of
output voltage and current
Semiconductors devices used
in chopper circuit are
unidirectional.
56. Four quadrant converters. (Forward motoring)
The directions of Io and Vo marked in the figure is taken as positive
direction output voltage (Vo) and output current (Io) follows the direction
as marked in figures then the chopper operation will be restricted in the
first quadrant of Vo - Io plane.