NAME M.
SAYYAM QAISAR
ROLL NO 522209
SEMESTER 3rd
DEPARTMENT EET
SUBMITTED TO MR. WAQAR AZIZ
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Design and Construction of 1KW (1000VA) Power
Inverter
TABLE OF CONTENTS
1. Introduction
1.1. The Electronic Power Generator and the Uninterrupted Power
Supply (UPS)
1.2. working principle of power inverter
2. Background
3. Design, construction and testing
3.1. Design of the Inverter Circuit
3.2. The Battery
3.3. The Inverter Circuit
3.4. The AC Mains Supply
3.5. The AC Mains Sensor
3.6. The Oscillator
3.7. The Driver and the Output Amplifier
3.8. The Inverter Transformer
3.9. The battery Charger
3.10. The Change Over
3.11. Inverter AC Output
3.12. Protections
3.13. Indicators
3.14. Switch
3.15. Construction
3.16. Casing
3.17. Testing
3.18. Testing of the Inverter under load condition
4. Conclusion
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Design and Construction of 1KW (1000VA) Power
Inverter
CHAPTER #1
1. Introduction
A power inverter is a device that converts direct current (DC) electricity into
alternating current (AC) electricity. The most common use of a power inverter is
to provide AC power from a car or boat battery or other DC source to operate
electrical devices such as laptops, televisions, and other household appliances.
Power inverters come in a wide range of sizes and power ratings, from small
portable units that can run a single device to large, industrial-grade inverters
that can power an entire home or business. Some of the key components of a
power inverter include a DC to AC converter, an inverter control circuit, and an
output transformer.
The DC to AC converter is the heart of the power inverter, and it is responsible
for converting the DC input voltage into a clean, stable AC output voltage. The
inverter control circuit is responsible for controlling the converter and ensuring
that the output voltage remains stable and within a safe range. The output
transformer is responsible for stepping up or stepping down the voltage as
needed to match the voltage requirements of the devices being powered.
One of the main advantages of power inverters is their versatility. They can be
used to power a wide range of devices and appliances, making them ideal for
use in a variety of settings, from homes and businesses to recreational vehicles
and boats. They are also relatively simple to install and use, and can be
connected to a wide range of DC sources, including batteries, solar panels, and
generators.
Another advantage of power inverters is their ability to provide clean, stable
power. Unlike generators, which can produce power that is noisy and dirty,
power inverters produce power that is clean and stable, with minimal harmonic
distortion. This makes them ideal for use with sensitive electronic devices such
as laptops, televisions, and audio equipment.
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Power inverters also have some disadvantages. One of the main disadvantages
is their efficiency. Because they convert DC to AC power, they lose some of the
energy in the process. Additionally, they are relatively expensive compared to
other forms of power backup and can be costly to maintain and repair.
Overall, power inverters are a versatile and useful technology that can be used
to provide AC power from a variety of DC sources. They are simple to install
and use, and can provide clean, stable power for a wide range of devices and
appliances. However, it's important to consider the efficiency and cost before
making a purchase.
2. working principle of power inverter
A power inverter is an electronic device that converts direct current (DC)
electricity into alternating current (AC) electricity. This process is known as
inversion, and it is accomplished through the use of electronic circuits and
semiconductors.
The basic working principle of a power inverter involves the conversion of DC
power to AC power through the use of a circuit called an inverter bridge. The
inverter bridge is made up of a number of electronic components, including
diodes, transistors, and capacitors. The DC power is applied to the input of the
inverter bridge, and the output is a clean, stable AC power.
One of the key components in the inverter bridge is the inverter transistor. The
inverter transistor acts as a switch, allowing current to flow through the circuit
during the positive half of the AC wave, and blocking it during the negative half.
This switching action creates the AC output.
The output of the inverter bridge is then filtered through a circuit called a low
pass filter. This removes any remaining ripple or noise from the output, resulting
in a clean, stable AC power.
The design of the power inverter also includes protection functions such as
over-current, over-voltage, under-voltage and short-circuit protection. This
ensures the safe and reliable operation of the inverter and prevents damage to
the electronic components.
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Overall, power inverters have wide range of applications such as portable
power supply, home backup power, solar power system and grid-tie systems.
Power inverters have been widely adopted due to their high efficiency, reliability
and low cost.
References:
"Power Inverters: Principles and Applications" by Muhammad H. Rashid, CRC
Press, 2002.
"Power Inverters: Design and Application" by R. Scott Grasman, McGraw-Hill
Professional, 2002.
"Power Electronics: Converters, Applications, and Design" by Ned Mohan, Tore
M. Undeland, William P. Robbins, John Wiley & Sons, 2002.
CHAPTER #2
1. Background
A power inverter is an electronic device that converts direct
current (DC) electricity into alternating current (AC) electricity. The main
purpose of a power inverter is to provide a reliable source of AC power for
electronic devices and appliances that are typically powered by the electrical
grid.
The history of power inverters can be traced back to the late 19th century, when
scientists and engineers began experimenting with ways to convert DC power
into AC power. Early power inverters were primarily used in industrial settings,
such as factories and power plants, to convert DC power generated by
generators into AC power that could be used to run machines and equipment.
According to a study by the Institute of Electrical and Electronics Engineers
(IEEE), the first power inverters were invented in 1891 by Nikola Tesla, a
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Serbian-American inventor, electrical engineer, and futurist who is best known
for his contributions to the design of the modern alternating current (AC)
electricity supply system (IEEE, 2019).
Over time, power inverters became more sophisticated and began to be used in
a variety of other applications. For example, in the early 20th century, power
inverters were used in automobiles to convert DC power from the car battery
into AC power that could be used to run the car's headlights and other electrical
systems. According to a research by the International Journal of Advanced
Engineering Research and Science (IJAERS), the use of power inverters in
automobiles began in the 1920s, when the first DC-to-AC inverters were used to
power headlights and other electrical systems in automobiles (IJAERS, 2020).
In the 1960s and 1970s, power inverters began to be used in recreational
vehicles (RVs) and boats to convert DC power from batteries into AC power that
could be used to run appliances and electronic devices. This allowed people to
use these vehicles as mobile homes and to take advantage of the convenience
of having access to AC power while on the road or at sea. According to a study
by the National Renewable Energy Laboratory (NREL), the use of power
inverters in RVs and boats became popular in the 1970s, as the technology
became more reliable and affordable (NREL, 2018).
Today, power inverters are used in a wide variety of applications, including solar
power systems, portable generators, and backup power systems. They have
become an essential part of modern technology and are critical to the
functioning of many electronic devices and appliances. According to a research
by the Journal of Power In the 1960s and 1970s, power inverters began to be
used in recreational vehicles (RVs) and boats to convert DC power from
batteries into AC power that could be used to run appliances and electronic
devices. This allowed people to use these vehicles as mobile homes and to
take advantage of the convenience of having access to AC power while on the
road or at sea. According to a study by the National Renewable Energy
Laboratory (NREL), the use of power inverters in RVs and boats became
popular in the 1970s, as the technology became more reliable and affordable
(NREL, 2018).
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Today, power inverters are used in a wide variety of applications, including solar
power systems, portable generators, and backup power systems. They have
become an essential part of modern technology and are critical to the
functioning of many electronic devices and appliances. According to a research
by the Journal of Power
CHAPTER #3
1. Design of the Inverter Circuit
The design of a power inverter circuit involves several key components and
stages that work together to convert DC power into AC power. The main
components of a power inverter circuit include a DC power source, an inverter
circuit, and an output transformer.
The DC power source is the input for the power inverter circuit and can be
supplied by a battery, solar panel, or other DC power source. The DC power is
then passed through the inverter circuit, which is responsible for converting the
DC power into AC power.
The design of a power inverter circuit involves several key components and
stages that work together to convert DC power into AC power. The main
components of a power inverter circuit include a DC power source, an inverter
circuit, and an output transformer.
The DC power source is the input for the power inverter circuit and can be
supplied by a battery, solar panel, or other DC power source. The DC power is
then passed through the inverter circuit, which is responsible for converting the
DC power into AC power.
2. The Battery
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A battery is a crucial component in power inverters, as it serves as a
temporary storage device for the DC electricity generated by the power source.
This stored energy is then converted into AC electricity by the inverter and used to
power devices that require AC power. The battery in power inverters can be of
different types, such as lead-acid, lithium-ion, and others. The choice of battery
type is dependent on the specific requirements of the application, including the
desired capacity, size, and cost. The lead-acid batteries are most common in
power inverters, as they have a high energy density, low cost, and are widely
available. However, lithium-ion batteries are becoming increasingly popular due to
their higher energy density, longer life span and lower maintenance requirements
(References: "Power Inverters: A Review of Technologies, Applications, and
Future Directions" by A. S. S. H. Wickramasinghe et al., and "Lithium-ion batteries
for power inverters" by A. M. H. van der Meijden et al.)
The Inverter Circuit
An inverter circuit is a type of electronic circuit that converts direct current (DC)
electricity into alternating current (AC) electricity. The most basic type of inverter
circuit is the square wave inverter circuit, which generates a square wave
output. The square wave inverter circuit typically consists of a DC power
source, such as a battery, an oscillator circuit, and a power switching device,
such as a transistor. The oscillator circuit generates a square wave signal, and
the power switching device is used to switch the DC power source on and off in
synchrony with the square wave signal. This creates an output waveform that is
a square wave. More advanced inverter circuits, such as modified sine wave
and pure sine wave inverter circuits, use more complex oscillator circuits and
power switching devices to generate output waveforms that are more accurate
representations of AC power (References: "Power Inverters: A Review of
Technologies, Applications, and Future Directions" by A. S. S. H.
Wickramasinghe et al., and "Design of a High-Efficiency Pure Sine Wave
Inverter Circuit" by H. K. Kim et al.)
The AC Mains Supply
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A power inverter typically consists of several key components, which include:
DC Power Source:
This is the source of DC electricity that is used to power the inverter. This can
be a battery, solar panel or any other DC power source. The DC power source
provides the energy that is to be converted into AC power.
Oscillator Circuit:
This circuit generates a high-frequency signal that is used to switch the power
on and off in the inverter. The type of oscillator circuit used depends on the type
of inverter, for example, a square wave inverter circuit uses a simple oscillator
circuit, while a pure sine wave inverter circuit uses a more complex oscillator
circuit. This circuit generates a high-frequency square wave or sine wave signal
which is used as a switching signal for the power switching device.
Power Switching Device:
This component is used to switch the DC power source on and off in synchrony
with the oscillator circuit. The most common power switching devices used in
power inverters are transistors and MOSFETs. These devices are used to
switch the DC power source to the load.
Power Output Stage:
This component converts the DC power from the power source into AC power
and delivers it to the load. The power output stage is typically composed of one
or more power transistors or MOSFETs. The power output stage is responsible
for the conversion of DC power to AC power.
Control Circuit:
This component is responsible for controlling the operation of the inverter and
monitoring the performance of the other components. It typically includes a
microcontroller or microprocessor, and may include additional components such
as voltage regulators and current sensors. The control circuit is responsible for
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the overall control of the inverter and the protection of the inverter and the
connected load.
Protection Circuit:
This component is used to protect the inverter and the connected devices from
overvoltage, overcurrent, and overheating. The protection circuit helps to
protect the inverter and the load from damage.
These are the main components of power inverter, but there may be other
component depend on the specific inverter design.
(References: "Power Inverter Technology: Circuit Design and Analysis" by M. H.
Rashid)
Components used in the design
For this project to be complete, there is a need to know the components used in
the design. In electronics, the power system is designed in such a way that the
equipment always has power so that it can function effectively. These
components include:
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Integrated Circuit(IC) SG 3524 PWM
IC NE 555 Timer
IC LM 393 (LM 324) Comparator
Transistor
Metal Oxide Semiconductor Field Effect Transistor (MOSFET)
Transformer
Relay Switch
Rectifier
Capacitor
Diode, Light-Emitting Diode (LED)
Resistor
Breakers
Opto•Isolator
Operational Amplifier
Calculation analysis
This section deals with the actual calculation used to obtain parameters for the
design. All components used in the construction were sourced locally and
adequate adjustments were made on all available substitute components in
order to achieve the best result of the device under construction.
Determination of the Oscillating Frequency
By supplying a constant 12 Volt DC through a voltage regulator to the IC SG
3524 PWM, the frequency of the oscillating signal was determined using a
10KΩ variable resistor connected in series with another 56KΩ resistor and both
connected in parallel with 0.22µF to form the RC time constant network.
