Upfc ppt
- 1. UPFC, UNIFIED POWER FACTOR CONTROL Under the Guidance of Submitted by Project Title
- 2. ABSTARCT • The time lag between the zero voltage pulse and zero current pul se duly generated by suitable operational amplifier circuits are fe d to two interrupt pins of the microcontroller where the program takes over to calculate the time difference between the voltage a nd current both for inductive load and capacitive load. • The time difference is calculated to display the leading power fac tor or the lagging power factor based on which appropriate num ber of opto-isolators triggers the back to back SCRs to switch eith er 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 ag ainst the voltage to display the power factor. • The microcontroller used in the project is of 8051 family which is of 8 bit.
- 4. MICROCONTROLLER (AT89S52/AT89C51) SCR OPTO-ISOLATOR LCD CURRENT TRANSFORMER INDUCTIVE CHOKE SHUNT CAPACITOR PUSH BUTTONS LED 1N4007 / 1N4148 RESISTOR CAPACITOR HARDWARE COMPONENTS
- 5. POWER SUPPLY 230 V AC 50 Hz 5V DC 12V step down transformer Filter(470µf) 5v RegulatorBridge rectifier
- 6. MICROCONTROLLER • It is a smaller computer • Has on-chip RAM, ROM, I/O ports... RAM ROM I/O Po rt Timer Serial COM Port Microcontroller CPU A single chip
- 7. INTERNAL STRUCTURE OF A MICRO CONTROLLER-AT89S5 2/51 CPU On-chip RAM On-chip ROM for program code 4 I/O Ports Timer 0 Serial Port OSC Interrup t Contro l External interrupts Timer 1 Timer/Counter Bus Con trol TxD RxDP0 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
- 10. SCR • A Silicon Controlled Rectifier (or Semiconductor Cont rolled Rectifier) is a four layer solid state device that c ontrols current flow • An SCR can be seen as a conventional rectifier contro lled by a gate signal • It is a 4-layered 3-terminal device • When the gate to cathode voltage exceeds a certain t hreshold, the device turns 'on' and conducts current
- 11. Contd.. • The operation of a SCR can be understood in terms o f 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 li ght doesn’t fall on triac so the triac is off means the cu rrent does not flow through the triac. • When logic 1 is given as input to the LED then light em itted by LED falls on triac so it starts conducting i.e., n ow 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 ±1.0VD C 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 charact ers per line by 2 lines, respectively. The standard is referred to as HD44780U, which refers to t he controller chip which receives data from an external sourc e (and communicates directly with the LCD.
- 16. 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-tim e kernels, debuggers, simulators, integrated environments, evaluation b oards, 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 obje ct code. Desktop compilers produce an output object code for the under lying 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 (unde rlying microprocessor in the computer). • For example compilers for Dos platform is different from the Com pilers for Unix platform So if one wants to define a compiler then compiler is a program that translates source code into object code.