1. UPFC, UNIFIED POWER FACTOR CONTROL
Project Title
UPFC, UNIFIED POWER FACTOR CONTROL
Under the Guidance of
Submitted by

2. ABSTARCT
The time lag between the zero voltage pulse and zero current pulse duly generated by suitable operational amplifier circuits are fed to two interrupt pins of the microcontroller where the program takes over to calculate the time difference between the voltage and current both for inductive load and capacitive load.
The time difference is calculated to display the leading power factor or the lagging power factor based on which appropriate number of opto-isolators triggers the back to back SCRs to switch either capacitor or inductor depending on the requirement.
This is achieved by using a set of capacitors and inductor forming as load whose current is sensed by a CT for further processing against the voltage to display the power factor.
The microcontroller used in the project is of 8051 family which is of 8 bit.

3. PROJECT BLOCK DIAGRAM

4. HARDWARE COMPONENTS MICROCONTROLLER (AT89S52/AT89C51) SCR
OPTO-ISOLATOR
LCD
CURRENT TRANSFORMER
INDUCTIVE CHOKE
SHUNT CAPACITOR
PUSH BUTTONS
LED
1N4007 / 1N4148
RESISTOR
CAPACITOR

5. POWER SUPPLY Bridge rectifier 5v Regulator 230 V AC 50 Hz 5V DC
Filter(470µf)
12V step down
transformer

6. It is a smaller computer Has on-chip RAM, ROM, I/O ports...
MICROCONTROLLER
It is a smaller computer
Has on-chip RAM, ROM, I/O ports...
RAM
ROM
I/O Port
Timer
Serial COM Port
Microcontroller
CPU
A single chip

7. INTERNAL STRUCTURE OF A MICRO CONTROLLER-AT89S52/51
CPU
On-chip RAM
On-chip ROM for program code
4 I/O Ports
Timer 0
Serial Port
OSC
Interrupt Control
External interrupts
Timer 1
Timer/Counter
Bus Control
TxD RxD
P0 P1 P2 P3
Address/Data
Counter Inputs

8. Features of AT89S51/52 Compatible with MCS®-51 Products
8K Bytes of In-System Programmable (ISP) Flash Memory
Endurance: 10,000 Write/Erase Cycles
4.0V to 5.5V Operating Range
Fully Static Operation: 0 Hz to 33 MHz
256 x 8-bit Internal RAM
32 Programmable I/O Lines
Three 16-bit Timer/Counters
Eight Interrupt Sources
Full Duplex UART Serial Channel
Interrupt Recovery from Power-down Mode
Watchdog Timer
Dual Data Pointer

9. Pin Description

10. SCR
A Silicon Controlled Rectifier (or Semiconductor Controlled Rectifier) is a four layer solid state device that controls current flow
An SCR can be seen as a conventional rectifier controlled by a gate signal
It is a 4-layered 3-terminal device
When the gate to cathode voltage exceeds a certain threshold, the device turns 'on' and conducts current

11. Contd..
The operation of a SCR can be understood in terms of a pair of tightly coupled Bipolar Junction Transistors
SCR has three states:
Reverse blocking mode, forward blocking mode, and forward conducting mode

12. Optocoupler
Opto coupler is a 6 pin IC. It is a combination of 1 LED and a traic. Pin 5 is not generally used and when light falls on the triac then it switches ON the triac.

13. Contd..
When logic zero is given as input to the LED then the light doesn’t fall on triac so the triac is off means the current does not flow through the triac.
When logic 1 is given as input to the LED then light emitted by LED falls on triac so it starts conducting i.e., now there will be current flowing through the triac.

14. QUAD VOLTAGE COMPARATOR LM339
FEATURES
● Wide single supply voltage range 2.0VDC TO 36VDC or dual supplies ±1.0VDC to ±18VDC
● Very low supply current drain (0.8㎃) independent
of supply voltage (1.0㎽/comparator at 5.0VDC)
● Low input biasing current 25㎁
● Low input offset current ±5㎁ and offset voltage
● Input common-mode voltage range includes ground
● Differential input voltage range equal to the power
supply voltage
● Low output 250㎷ at 4㎃ saturation voltage
● Output voltage compatible with TTL, DTL, ECL, MOS
and CMOS logic system
● Moisture Sensitivity Level 3

15. LIQUID CRYSTAL DISPLAY (LCD)
Most common LCDs connected to the microcontrollers are 16x2 and 20x2 displays.
This means 16 characters per line by 2 lines and 20 characters per line by 2 lines, respectively.
The standard is referred to as HD44780U, which refers to the controller chip which receives data from an external source (and communicates directly with the LCD.

16. If an 8-bit data bus is used the LCD will require 11 data lines
LCD BACKGROUND
If an 8-bit data bus is used the LCD will require 11 data lines
(3 control lines plus the 8 lines for the data bus)
The three control lines are referred to as EN, RS, and RW
EN=Enable (used to tell the LCD that you are sending it data)
RS=Register Select (When RS is low (0), data is treated as a command)
(When RS is High(1), data being sent is text data )
R/W=Read/Write (When RW is low (0), the data written to the LCD)
(When RW is low (0), the data reading to the LCD)

17. Soft ware Requirements
Keil an ARM Company makes C compilers, macro assemblers, real-time kernels, debuggers, simulators, integrated environments, evaluation boards, and emulators for ARM7/ARM9/Cortex-M3, XC16x/C16x/ST10, 251, and 8051 MCU families.
Compilers are programs used to convert a High Level Language to object code. Desktop compilers produce an output object code for the underlying microprocessor, but not for other microprocessors.

18. i.e the programs written in one of the HLL like ‘C’ will compile the code to run on the system for a particular processor like x86 (underlying microprocessor in the computer).
For example compilers for Dos platform is different from the Compilers for Unix platform  So if one wants to define a compiler then compiler is a program that translates source code into object code.

19. QUERIES ?

20. THANKYOU