1. EXPERT SYSTEMS AND SOLUTIONS
Email: expertsyssol@gmail.com
expertsyssol@yahoo.com
Cell: 9952749533
www.researchprojects.info
PAIYANOOR, OMR, CHENNAI
Call For Research Projects Final
year students of B.E in EEE, ECE,
EI, M.E (Power Systems), M.E
(Applied Electronics), M.E (Power
Electronics)
Ph.D Electrical and Electronics.
Students can assemble their hardware in our
Research labs. Experts will be guiding the
projects.

2. MICROCONTROLLER BASED PWM INVERTER
Under the guidance:
Mr.P.PONSANKER.M.E.,
LECTURER,
DEPARTMENT OF EEE
DSEC.
PRESENTED BY:
K.SARAVANAN.
K.MEHANATHAN.
J.KAVIARASAN.
A.SUHAILRASEED.

3. Abstract
Microcontroller based PWM inverter is the recent
technique in which output voltage produced by the
inverter is easily controlled.In this circuit five
MOSFET’s used for high speed switching purpose alone
with eight diodes. Here four diodes used as freewheeling
diode and remaining four diodes connected across the
MOSFET.
Single pulse gating signals are generated by
microcontroller.The microcontroller is programmed
using keil micro vision2 and ISPRO vision3(serial
programmer). Atmel 89c52 is used for generation of
gating pulses.

4. This pulse width modulation technique is very much useful
for the reduction of harmonics in the inverter output voltage.
The pulses are produced directly by the microcontroller
through it’s programing. The width of the pulses are easily
varied by the program.
Keil software is used for checking and debugging the
program of the controller. ISPRO software is used for store
the program in microcontroller with the help of computer.
Simulation of single phase and three phase inverter is done by
using MATLAB simulation software. After simulation
process a necessary hardware for single phase inverter is to
be produced.

5. INVERTER
An inverter is a circuit which converts a D.C power into an
A.C power at desired output voltage and frequency
This conversion can be achieved by controlled turn-on and
turn-off devices like BJT,MOSFET and IGBT.
For low and medium power outputs the above devices
were used.
The output waveform produced by the inverter should be
sinusoidal.

6. • The commonly used PWM control techniques are:
• (a) Single-pulse width modulation (SPWM)
• (b) Multiple-pulse width modulation (MPWM)
• (c) Sinusoidal pulse width modulation (sin PWM)
(a) Single-pulse width modulation:
In single-pulse width modulation control, there is only one
pulse per half-cycle and the width of the pulse is varied to
control the inverter output voltage. The generation of gating
signals and output voltage of single phase full bridge
inverter is shown in Fig

8. (a) Multiple pulse-width modulation:
In this method of pulse width modulation, the harmonic content can be
reduced using several pulses in each half-cycle of output voltage. By
comparing a reference signal with a triangular carrier wave, the gating
signals are generated for turning-on and turning-off of a thyristor, as
shown in Fig

10. Sinusoidal pulse width modulation :
In this method of modulation, several pulses per
half-cycle are used as in the case of multiple pulse
width modulation. Instead of maintaining the
width of all pulses the same as in the case of
multiple pulse modulation, width of each pulse is
varied proportional to the amplitude of a sine-
wave evaluated at the centre of the same pulse. By
comparing a sinusoidal refence signal with a
triangular carrier wave of frequency, fc, the gating
signals are generated, as shown in Fig

12. Single phase five level inverter
PWM inverter can control their output voltage and
frequency. and also they reduce the harmonic
components in load currents. The approach in these
project also have lot of merits such as an improved output
waveform, smaller size and low cost In single-phase
three-level inverter output has three values: zero,
positive, and negative supply dc voltage level. Therefore,
the harmonic components of their output voltage are
determined by carrier frequency and switching functions.
Moreover, the harmonic reduction of them is limited to
certain degree. The developed a single-phase five-level
PWM inverter has an output voltage with five levels, they
are
1.Zero,
2.Half Positive,
3.Full Positive,
4. Half Negative,
5.Full Negative supply dc voltage levels and hence
called single-phase five-level PWM inverter.

17. (a) State 1: +(Vd/2)-Q1-R-L-Q4-(-Vd/2), output
voltage positive (Vo=Vd) and direction of load current
is negative (Io= (+)).
(b) State 2: (-Vd/2)-D1-R-L-D4- (+Vd/2), output
voltage positive (Vo =Vd) and direction of load current
is negative (Io= (-)).
(c) State 3: +(Vd/2)-D5-Q5-D8-L-R-Q4, output voltage
positive (Vo = Vd/2) and direction of load current is
negative (Io= (+)).
(d) State 4: -(Vd/2)-D4-L-R-D6-Q5-D7- (+Vd/2), output
voltage positive (Vo =Vd/2) and direction of load
current is negative (Io= (-)).
(e) State 5: L-Q4-D3-R -L, output voltage positive (Vo
= 0) and direction of load current is negative (Io= (+)).

19. (f) State 6: L-R-Q3-D4-L, output voltage positive (Vo=
0) and direction of load current is negative (Io=(-)).
(g) State 7: -(Vd/2-D5-Q5-D8-R-L-D2- (+Vd/2), output
voltage positive (Vo = -Vd/2) and direction of load
current is negative (Io= (+)).
(h) State 8: +(Vd/2)-Q2-L-R-D6-Q5-D7- (-Vd/2), output
voltage positive (Vo = -Vd/2) and direction of load
current is negative (Io= (-)).
(i) State 9: -(Vd/2)-D3-R-L-D2- (+Vd/2), output voltage
positive (Vo = -Vd) and direction of load current is
negative (Io= (+)).
(j) State 10: +(Vd/2)-Q2-L-R-Q3- (-Vd/2), output
voltage positive (Vo =-Vd) and direction of load current
is negative
(Io= (-)).

20. Keil microvision2
What's New in µVision3
µVision3 adds many new features to the
Editor like Text Templates, Quick
Function Navigation, Syntax Coloring
with brace highlighting, Configuration
Wizard for dialog based startup and
debugger setup. µVision3 is fully
compatible to µVision2 and can be used
in parallel with µVision2.

21. What is µVision3?
µVision3 is an IDE (Integrated Development
Environment) that helps you write, compile,
and debug embedded programs. It
encapsulates the following components:
A project manager.
A make facility.
Tool configuration.
Editor.
A powerful debugger.

22. To help you get started, several example programs
(located in the C51Examples,
C251Examples, C166Examples, and
ARM...Examples) are provided.
HELLO is a simple program that prints the string "Hello
World" using the Serial Interface.
MEASURE is a data acquisition system for analog and
digital systems.
TRAFFIC is a traffic light controller with the RTX Tiny
operating system.
SIEVE is the SIEVE Benchmark.
DHRY is the Dhrystone Benchmark.
WHETS is the Single-Precision Whetstone Benchmark.

23. Additional example programs not listed
here are provided for each device
architecture.
Building an Application in µVision2
To build (compile, assemble, and link)
an application in µVision2, you must:
1.Select Project - Open Project (for
example, C166EXAMPLESHELLO
HELLO.UV2).
2.Select Project - Rebuild all target files
or Build target.
µVision2 compiles, assembles, and links
the files in your project.

24. Creating Your Own Application in
µVision2
To create a new project in µVision2, you
must:
1. Select Project - New Project.
2. Select a directory and enter the name of the
project file.
3. Select Project - Select Device and select an
8051, 251, or C16x/ST10 device from the
Device Database™.
4. Create source files to add to the project.
5. Select Project - Targets, Groups, Files.
Add/Files, select Source Group1, and add the
source files to the project.

25. Debugging an Application in µVision2
To debug an application created using µVision2,
you must:
1.Select Debug - Start/Stop Debug Session.
2.Use the Step toolbar buttons to single-step
through your program. You may enter G, main
in the Output Window to execute to the main C
function.
3.Open the Serial Window using the Serial #1
button on the toolbar.
Debug your program using standard options like
Step, Go, Break, and so on.

26. CONCLUSION
Single-phase five-level PWM inverter to reduce the harmonic
components of output voltage and load current. The
operational principles and the switching functions are
analyzed in detail. The controller is also designed for the
single-phase five-level PWM inverter to keep the output
voltage being sinusoidal and have high dynamic performance
even in the cases of load variations and also the single-phase
five-level PWM inverter has been compared with a single-
phase three-level PWM inverter. The simulation results show
that Total harmonic distortion of the five-level inverter is
considerably alleviated.