2. Introduction
The main aim of this project is to use solar energy for
street light of our collage at night. Solar energy is
converted to electrical energy by photo-voltaic(PV)
cells. This energy is stored in batteries during day time
for the utilization purpose whenever required.
A solar inverter, or PV inverter, converts the direct
current (DC) output of a photovoltaic solar panel into a
utility frequency alternating current (AC) that can be
fed into a commercial electrical grid or used by a local,
off-line electrical network.
4. Solar inverters may be classified
into three broad types
Stand-alone inverters
Grid-tie inverters
Battery backup inverters
5. Stand-Alone Inverters
It is used in isolated systems.
The inverter draws its DC energy from batteries charged by
photovoltaic arrays.
Many stand-alone inverters also incorporate integral battery
chargers to replenish the battery from an AC source.
Normally these do not interface in any way with the utility
grid.
It does not required to have anti-islanding protection.
6. Grid-Tie Inverters
It match phase with a utility-supplied sine wave.
Grid-tie inverters are designed to shut down
automatically upon loss of utility supply.
They do not provide backup power during utility
outages.
Grid tie inverter converts DC power produced by
PV array to AC power.
7. Battery Backup Inverters
These are special inverters which are designed to draw
energy from a battery.
It manage the battery charge via an on board charger,
and export excess energy to the utility grid.
These inverters are capable of supplying AC energy to
selected loads during a utility outage
The battery backup inverters are also required to be
installed with an anti-islanding protection.
9. Battery
An electrical battery is a combination of one or
more electrochemical cells, used to convert
stored chemical energy into electrical energy.
The battery has become a common power source
for many household, robotics and industrial
applications.
Larger batteries provide standby power for
telephone exchanges or computer data centers
10. PWM Inverter IC
The PWM Inverter is used to develop the PWM
pulses based on a fixed frequency using common
oscillator.
The IC SG3524 operates at a fixed frequency, the
oscillation frequency is determined by one timing
resistor RT and one timing capacitor CT.
The SG3524 contains an inbuilt 5V regulator that
supplies as a reference voltage, also providing the
SG3524 internal regulator control circuitry.
11. PWM Inverter IC
Comparator provides a linear control of the
output pulse width (duration) by the error
amplifier.
The resultant PWM pulse from the comparator is
passed to the corresponding output pass
transistor (Q1, Q2 refer block diagram) using the
pulse steering flip flop, which is synchronously
toggled by the oscillator output.
12. MOSFET(IRF 510)
The metal–oxide–semiconductor field-effect transistor
(MOSFET, MOS-FET, or MOS FET) is a device used for
amplifying or switching electronic signals.
The basic principle of the device a voltage on the
oxide-insulated gate electrode can induce a conducting
channel between the two other contacts called source
and drain.
It is by far the most common transistor in both digital
and analog circuits, though the bipolar junction
transistor was at one time much more common.
13. BC547 (NPN –Transistor)
The BC547 transistor is an NPN Epitaxial Silicon
Transistor.
It is used in general-purpose switching and
amplification BC847/BC547 series 45 V, 100 mA
NPN general-purpose transistors.
The ratio of two currents (Ic/Ib) is called the DC
Current Gain of the device and is given the symbol
of hfe or nowadays Beta, (β).
14. BC547 (NPN –Transistor)
The current gain from the emitter to the collector terminal, Ic/Ie, is called Alpha,
(α), and is a function of the transistor itself
15. Solar Panel
Solar panel refers to a panel
designed to absorb the sun's rays as
a source of energy for generating
electricity.
Solar Panel is an array of Several
solar cells (Photovoltaic cells).
The arrays can be formed by
connecting them in parallel or
series connection depending upon
the energy required.
16. Working of Solar Panel and
Inverter
Expose the cell to light, and the energy from each photon (light
particle) hitting the silicon, will liberate an electron and a
corresponding hole.
If this happens within range of the electric field’s influence, the
electrons will be sent to the N side and the holes to the P one,
resulting in yet further disruption of electrical neutrality.
This flow of electrons is a current; the electrical field in the cell
causes a voltage and the product of these two is power.
The solar energy is stored in the battery from Photo-Voltaic cells.
17. Working of Solar Panel and
Inverter
• This stored energy of the battery is converted to AC
supply of 50Hz frequency using PWM inverter IC with
MOSFET gate driver IC to the driver MOSFET bridge
and step-up the voltage by a transformer.
18. Needs Of Solar Power
Electricity rate has hiked in last four years.
We need to focus on alternate option because
of environmental concerns.
It has several advantages over other forms of
electricity generation.
19. About The Inverter
This energy generated by the panel, in the form of direct
current (DC), is transmitted to the inverter. The job of the
inverter is to convert the DC power the solar panel has
generated to alternating current (AC) that is transmitted on
the grid. The inverter converts DC to AC by using two
switches which convert the positive only DC power to an
alternating positive to negative AC power.
The inverter will then step up the voltage from 12 volts to
220volts, which is the voltage used throughout the street
light. This conversion of voltage is what allows a 12 volt DC
solar polar to be tied into a 220 volt AC.
20. Advantage
High efficiency and outstanding energy harvest in
a small modular design.
Ease of installation to save time and money.
Is compatible with other GT Series models to
customize the inverters to the array.
Central and micro inverters can be up to 95%
efficient.
21. Disadvantage
Central inverters is difficult to do properly and is usually
the hardest part of designing a solar array.
For central inverter, the output from your whole array
can drop significantly, if any one of the panel is shaded.
Another weakness of a central inverter is that you
won’t be able to monitor how each individual panel is
performing.
Micro inverters are more expensive.
22. Applications
Can use Solar Inverter for domestic
application.
It can be plugs in your house for your TV,
computer, and other wired products.
Can use Solar Power Inverters For Industrial
Application.
23. Conclusion
• Inverters are usually about 95% efficient.
Inverters play a significant role in providing
alternate current supplies at the times of
crucial power requirements. The primary use
of solar inverters is to convert direct current to
alternating current through an electrical
switching process.