The document discusses various power electronics applications including energy storage elements like inductors and capacitors, uninterruptible power supplies (UPS), and switch mode power supplies (SMPS). It describes the basic working principles of inductors, capacitors, different types of UPS systems including static and rotary, and various SMPS topologies such as forward, flyback, non-isolated, and isolated converter modes. Key applications and components of these power electronic circuits are explained in detail across multiple pages.
Electrical fault is the deviation of voltages and currents from nominal values or states. Under normal operating conditions, power system equipment or lines carry normal voltages and currents which results in a safer operation of the system.
Electrical fault is the deviation of voltages and currents from nominal values or states. Under normal operating conditions, power system equipment or lines carry normal voltages and currents which results in a safer operation of the system.
Inter Connected Power System(Turbine Speed Governing Mechanism)Raviraj solanki
Inter Connected Power SystemTOPIC : Turbine Speed Governing Mechanism
Introduction
Turbine Speed Governing Mechanism
Mathematical Modeling
Adjustment Of Governor Characteristics
The speed governing system consists of the following parts .
Speed governor
Linkage mechanism
Hydraulic amplifier
Speed changer
The electricity supply industry is undergoing a profound transformation worldwide. Market forces, scarcer natural resources, and an ever-increasing demand for electricity are some of the drivers responsible for such unprecedented change. Against this background of rapid evolution, the expansion programs of many utilities are being thwarted by a variety of well-founded, environment, land-use, and regulatory pressures that prevent the licensing and building of new transmission lines and electricity generating plants.
Part of Lecture series on EEE-413, Electrical Drives (DC Drives) delivered by me to students of VIII Semester B.E. (Electrical), Session 2018-19.
Z. H. College of Engg. & Technology, Aligarh Muslim University, Aligarh.
Missing materials will be uploaded shortly.
Please comment and feel free to ask anything related. Thanks!
three level diode clamp inverter. that converts any type of DC ( rectified, PV cell, battery etc.) to AC supply. we made by mosfet and ardiuno . in this ppt we present the Simulink model of a three-level inverter and the hardware presentation of the inverter.
These slides are all about Phasor Measurement Units (PMUs). An introduction to PMU is presented as a preliminary knowledge for the course 'Distribution Generation and Smart Grid'. Your valuable suggestions are welcome.
Inter Connected Power System(Turbine Speed Governing Mechanism)Raviraj solanki
Inter Connected Power SystemTOPIC : Turbine Speed Governing Mechanism
Introduction
Turbine Speed Governing Mechanism
Mathematical Modeling
Adjustment Of Governor Characteristics
The speed governing system consists of the following parts .
Speed governor
Linkage mechanism
Hydraulic amplifier
Speed changer
The electricity supply industry is undergoing a profound transformation worldwide. Market forces, scarcer natural resources, and an ever-increasing demand for electricity are some of the drivers responsible for such unprecedented change. Against this background of rapid evolution, the expansion programs of many utilities are being thwarted by a variety of well-founded, environment, land-use, and regulatory pressures that prevent the licensing and building of new transmission lines and electricity generating plants.
Part of Lecture series on EEE-413, Electrical Drives (DC Drives) delivered by me to students of VIII Semester B.E. (Electrical), Session 2018-19.
Z. H. College of Engg. & Technology, Aligarh Muslim University, Aligarh.
Missing materials will be uploaded shortly.
Please comment and feel free to ask anything related. Thanks!
three level diode clamp inverter. that converts any type of DC ( rectified, PV cell, battery etc.) to AC supply. we made by mosfet and ardiuno . in this ppt we present the Simulink model of a three-level inverter and the hardware presentation of the inverter.
These slides are all about Phasor Measurement Units (PMUs). An introduction to PMU is presented as a preliminary knowledge for the course 'Distribution Generation and Smart Grid'. Your valuable suggestions are welcome.
Different types of transistors and their functionselprocus
This article discusses about types of transistors and basic applications.Common types of transistor are BJT, FET, HBT, Darlington, Schottky, JFET, Diffusion
the ratio of the actual electrical power dissipated by an AC circuit to the product of the r.m.s. values of current and voltage. The difference between the two is caused by reactance in the circuit and represents power that does no useful work.
Research Inventy : International Journal of Engineering and Scienceinventy
Research Inventy : International Journal of Engineering and Science
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
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
100 watt inverter using IC CD4047 and MOSFET IRF540
CD 4047 is a low power CMOS astable/monostable multivibrator IC. Here it is wired as an astable multivibrator producing two pulse trains of 0.01s which are 180 degrees out of phase at the pins 10 and 11 of the IC. Pin 10 is connected to the gate of Q1 and pin 11 is connected to the gate of Q2. Resistors R3 and R4 prevents the loading of the IC by the respective MOSFETs. When pin 10 is high Q1 conducts and current flows through the upper half of the transformer primary which accounts for the positive half of the output AC voltage. When pin 11 is high Q2 conducts and current flows through the lower half of the transformer primary in opposite direction and it accounts for the negative half of the output AC voltage.
This article speaks about the different energy domains, sensors, actuation techniques, transduction techniques, fabrication materials, physical strength requirements, substrate materials and De Vries formula used in MEMS technology.
This article discusses MEMS, i.e. Micro-Electro Mechanical Systems.
It gives a rudimentry idea of MEMS technology, its block diagram, applications, advantages and disadvantages. It also gives a brief idea on the working principle of MEMS devices.
Basic concept and techniques of Flow measurement are described.
Bernoulli's Principle, Hagen Poiseuille Law, Coanda and Coriolis Effect are described..
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.
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.
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.
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.
2. Contents:
Energy Storage Elements
Uninterruptible Power Supply (UPS)
Switch Mode Power Supply (SMPS)
2
3. Energy Storage Elements: Inductors & Capacitors
Inductors and Capacitors are the fundamental energy storage elements.
These are the essential basic components to build any power electronics circuit.
3
4. Inductors:
Inductance is the name given to the property of a circuit whereby there is an e.m.f.
induced into the circuit by the change of flux linkages produced by a current change.
When the e.m.f. is induced in the same circuit as that in which the current is changing,
the property is called self-inductance(L) .
When the e.m.f. is induced in a circuit by a change of flux due to current changing in
an adjacent circuit, the property is called mutual inductance(M) .
Inductors store the electrical energy in the form of electro magnetic field.
The unit of inductance is the Henry (H) .
Henry(H): A circuit has an inductance of one Henry when an e.m.f. of one Volt is
induced in it by a current changing at the rate of one Ampere per second.
𝑉 = 𝐿 𝑑𝑖 𝑑𝑡
where V = voltage across Inductor in Volts; L = Inductance in henry; i = Current
through the inductor in Ampere.
4
5. Inductors:
The current through an inductor cannot change instantaneously.
The voltage across the inductor changes instantaneously from positive to negative
when we switch from storing energy in the inductor to removing energy from the
inductor. ( i.e. the di/dt is changing from positive to negative)
The converse of the equation is
𝐼 = 1 𝐿 𝑉𝑑𝑡 + 𝐼𝑖𝑛𝑖𝑡𝑖𝑎𝑙
It is used to find the inductor current when we know the voltage across the inductor.
5
6. Capacitors:
A capacitor is an electrical device that is used to store electrical energy.
Next to the resistor, the capacitor is the most commonly encountered component in
electrical circuits.
For example, capacitors are used to smooth rectified AC outputs, they are used in
telecommunication equipment—such as radio receivers—for tuning to the required
frequency, they are used in time delay circuits, in electrical filters, in oscillator circuits,
and in magnetic resonance imaging (MRI) in medical body scanners, to name but a few
practical applications.
Capacitors store electrical energy in the form of electro static field.
Unit of capacitance is Farad (F).
The current waveform of the filter capacitor of a switching power supply is typically a
saw tooth waveform.
The change in voltage in the output waveform is called as ripple voltage.
The goal of the capacitor is to limit this ripple voltage.
6
7. Capacitors:
𝑄 = 𝐶𝑉
Q = Charge; C = Capacitance in Farad; V = Voltage across Capacitor in volts.
A Capacitor is one farad if storing one coulomb of charge creates one volt.
𝑉 = 1 𝐶 𝑖𝑑𝑡 + 𝑉𝑖𝑛𝑖𝑡𝑖𝑎𝑙 ≡ 𝐼 = 𝐶 𝑑𝑉 𝑑𝑡
We can control the ripple voltage by controlling two variables. i.e. by increasing the
capacitance (C) or by decreasing dt.
One of the major advantage of the Switching Power Supplies is that we can make dt very
small by increasing the switching frequency.
It allows the value of C also be very small.
7
8. Uninterruptable Power Supply (UPS)
A Uninterruptible Power Supply (UPS) is a device that maintains a continuous supply
of electric power to the equipment by supplying power from a separate source when
the main power supply is not available.
The UPS is normally inserted between the commercial utility mains and the critical
loads.
When a power failure occurs, the UPS will immediately switch from utility power to
its own power source.
The Uninterruptible Power Supply (UPS) is used in applications where loss of the
mains supply could be disastrous, like hospital operating theatres or intensive care
units.
8
10. Types of UPS
UPS systems are generally classified as
1. Static UPS systems, which use power electronic converters with semiconductor devices.
2. Rotary (or dynamic) UPS systems, which use electromechanical engines such as motors
and generators.
3. The combination of both static and rotary UPS systems is often called Hybrid UPS
systems.
10
11. Static UPS
Static Uninterruptible Power Supply systems are based on power electronic devices.
The continuous development of devices like IGBTs allows high frequency operation,
which results in a fast transient response and low total harmonic distortion (THD) in
the output voltage.
Solid state (Static) UPS system consists of several major elements like Rectifier &
Battery charger, inverter, static transfer switch, battery bank.
All UPS systems use an internal battery that produces AC power via an inverter.
How and when this inverter comes into play largely determines the effectiveness of the
UPS.
All UPS systems have at least one large, low-frequency, magnetic component, usually
a transformer. In early days these transformers are large and heavy. Now a days smaller
size, less expensive high frequency magnetics are used.
The main advantages of higher frequencies are that acoustic noise can be reduced, and
flicker components become smaller.
11
12. Static UPS
According to the international standards, Static Uninterruptible Power Supply systems
can be classified into three main categories:
1. Off-line UPS
2. On-line UPS
3. Line Interactive UPS
12
13. Off line and On line Static UPS
Off Line Static UPS
In the case of the off-line system, in normal operation power is supplied directly from
AC mains.
In the event of mains failure, a transfer switch disconnects the power line and connects
the inverter to the load.
When the mains power is restored, the load is reconnected to the power line.
On Line Static UPS
In the case of on-line systems, the rectifier-inverter combination supplies the load
power from the AC mains during normal operation.
In the event of mains failure, the battery automatically supplies the dc link to the
inverter and there is no time delay involved.
When the rectifier-inverter system fail, the load could be transferred to ac mains using
a transfer switch.
13
16. Line Interactive Static UPS
In line interactive UPS system, when the mains supply is present, the static switch is
ON.
The static switch connects load to mains supply through inductor L.
The batteries are charged through the charger block.
When main power supply is turned off, the mains static switch is open.
Consequently the inverter turns ON and provides power to the load.
When the main power is available, the Charger/Inverter block operates as a charger and
when the main supply is not available it works as an Inverter.
16
18. Switch Mode Power Supply (SMPS)
SMPS stands for switched mode power supply. It is an electronic device in which
energy conversion and regulation is provided by power semiconductors that are
continuously switching with high frequency between "on" and "off" states. An output
parameter (usually output voltage) is controlled by varying duty cycle, frequency or a
phase shift of these transitions.
D.C. to D.C. converters and D.C. to A.C. Converters belong to the category of
Switched Mode Power Supplies (SMPS).
The input D.C. Supply is chopped at a higher frequency around 15 to 50 kHz using an
active device like the BJT, power MOSFET or SCR and the converter transformer.
The size of the ferrite core reduces inversely with the frequency.
18
19. Switch Mode Power Supply (SMPS)
AC power first passes through fuses and a line filter.
Then it is rectified by a full-wave bridge rectifier.
The rectified voltage is next applied to the power factor correction (PFC) pre-regulator
followed by the downstream DC-DC converter(s).
19
20. Switch Mode Power Supply (SMPS)
If we see as a black box with two input terminals and two output terminals, the SMPS
is identical to Linear power supply.
The linear regulator regulates a continuous flow of current from the input to load in
order to maintain a constant load voltage.
The SMPS regulates the current flow by chopping up the input voltage and controlling
the average current by controlling duty cycle.
The pulse width modulated SMPS are classified into two types based on the basic
principle of operation.
They are
(1) Forward Mode Switching Regulators (or) Forward Mode SMPS
(2) Fly-back Mode Switching Regulators (or) Fly back Mode SMPS
20
23. DC to DC Converter SMPS 23
DC to DC Converter SMPS Working Principle.
High – voltage DC power is directed obtained from DC power source.
At an extremely high switching speed usually in the range of 15 KHz to 50 KHz.
And then it’s fed to a step-down transformer that is comparable to the weight & size of
a transformer unit of 50Hz.
The output of the step down transformer is then further provided to the rectifier.
This filtered & rectified output DC power is utilized as a source for loads & a sample
of this output power is used as a feedback for controlling the output voltage.
The ON time of the oscillator is controlled with this feedback voltage, & a closed-loop
regulator is formed.
24. DC to DC Converter SMPS 24
The output of the smps is regulated by means of PWM (Pulse-Width-Modulation).
As given in the circuit, the switch can be driven by the PWM-oscillator, such that the
power delivered to the step-down transformer is controlled indirectly, & hence, the
output is controlled by the pulse-width-modulation, as this pulse-width signal & the
output-voltage are inversely related to each other.
If the duty cycle is 50%, the maximum power is transported through the step-down
transformer & if duty cycle decreases, the power transferred will also decrease by
decreasing the dissipation of power.
26. AC to DC Converter SMPS 26
There is an AC input in an AC to DC converter SMPS.
It is converted into DC by rectification process using a rectifier & filter.
This unregulated DC voltage is fed to the large-filter capacitor or Power Factor
Correction (PFC) circuits for correction of power factor as it is affected.
This is because around voltage peaks, a short current is drawn through the rectifier,
these current pulses have appreciably high-frequency energy which causes the power
factor to decrease.
Instead of direct DC power supply, here AC input is used.
Conversion of AC into DC & switching is done by using a power ‘MOSFET’ amplifier
with which very high gain can be obtained.
MOSFET transistor has low on-resistance & can withstand high current.
The switching-frequency is chosen such that it must be placed inaudible to normal
human beings (mostly above 20KHz) & switching action is controlled by a feedback
using the PWM-oscillator.
27. AC to DC Converter SMPS 27
The AC voltage is again fed to the output transformer. The output of this transformer is
then rectified & smoothed by using the output rectifier & filter.
In order to control the output voltage a feedback circuit is used by comparing it with
the reference voltage.
28. Forward Mode Switching Regulators SMPS
Forward Mode SMPS form a large family of switching power supply topologies.
They can be identified by an L-C filter just after the power switch or after the output
rectifier on the secondary of a transformer.
A form of the forward-mode regulator is buck regulator.
In this category, the power switch is placed directly between the input voltage and the
Inductor.
In between the power switch and the filter section (Inductor) there may be a
transformer for stepping up or down the input voltage as in transformer-isolated
forward regulators.
When the switch is turned-on the load current passes from the input source, through the
inductor to the load, and back again through the return lines to the input source.
At this moment the diode is reverse biased.
28
30. When the switch is turned-off, the inductor still expects current to flow through it.
The former current path through the input source is open-circuited at this moment.
So the free wheeling diode starts to conduct and maintain a closed current loop through
the load.
When the switch turns on again, the voltage stored in the inductor reverse biases the
freewheeling diode.
In summary, the forward current is always flowing through the inductor and thus these
supplies named as forward mode switching regulators.
The amount of energy being delivered to the load is determined by duty cycle of the
switch.
Duty cycle is defined as 𝐷 = 𝑇𝑜𝑛 𝑇𝑜𝑛 + 𝑇𝑜𝑓𝑓
For forward mode switching regulators the value of duty cycle is in between 5% and
95%
30
31. Fly back Mode Switching Regulators SMPS
Very low output power of less than 100W (watts)
This type of SMPS use the same four basic components (L, D, Switch, C) as that of
forward mode switching regulators, but the they are rearranged.
Here the Inductor is placed directly between the input voltage source and the power
switch.
When the switch is turned On, current is being drawn through the inductor.
It causes energy to be stored in the inductor.
When the switch is turned-off, the current cannot change the direction instantaneously
and it tries to flow in the same direction as before.
Thus the inductor voltage reverses (or flies back).
Thus the diode turns on and the energy from the inductor stores in the capacitor.
Since the inductor voltage flies back above the input voltage , the voltage that appears
on the output capacitor is higher than the input voltage.
31
33. The only storage for the load is the output filter capacitor.
It makes the output ripple voltage of fly back converters worse than their forward-
mode regulators.
Due to the restriction of the time required to empty the inductor’s flux into the output
capacitor, the duty cycle is limited to 0-50% (the forward mode switching regulator
duty cycle is in between 5 - 95%)
Based on the presence of transformer in the circuit, the SMPS is classified as follows:
(1) Non-transformer-Isolated Switching Power Supply Topologies
(2) Transformer-Isolated Switching Power Supply Topologies
33
34. Non-transformer-Isolated Switching Power
Supply Topology SMPS
The non-transformer-isolated type of SMPS are easy to understand.
They are used when some external component provides the DC isolation or protection
in place of the switching supply.
These external components are usually 50-60 Hz transformers or isolated bulk power
supplies.
Typically they are used in local board-level voltage regulation.
In these topologies, only the semiconductors provide the DC isolation from the input to
the output. Failure of the switch leads to catastrophic failure.
Some of the non-transformer-isolated topologies are:
1. Buck regulator
2. Boost regulator
3. Buck-boost regulator
34
35. Transformer-Isolated Switching Power Supply
Topology (SMPS)
Power Supplies that are intended to run directly from the AC source (offline power
supplies) require a transformer to isolate the load side from AC lines.
Transformers can also be used in power supplies where isolation is required for other
reasons such as medical equipment use.
Some of the transformer-isolated topologies are
1. Fly back regulator
2. Push-pull regulator
3. Half-Bridge regulator
4. Full-Bridge regulator
35
36. References:
Power Electronics A to Z: ANALOG CIRCUIT DESIGN BASICS
Power Electronics A to Z: UNINTERRUPTIBLE POWER SUPPLY [UPS]
Power Electronics A to Z: SWITCH MODE POWER SUPPLY [SMPS]
36