TWO PHASE BLDC MOTOR SPEED CONTROL USING FUZZY

TWO PHASE BLDC MOTOR SPEED CONTROL USING FUZZY LOGIC CONTROL Submitted By

Introduction Fuzzy controllers are very simple conceptually. They consist of an input stage, a processing stage, and an output stage. The project shall be using a microcontroller with a set of switches or a matrix key pad to define the speed of the BLDC in percentage of its rated speed being displayed in a LCD display. The output from the microcontroller drives the motor through a driver circuit. PWM (Pulse Width Modulation) wave can be used to control the speed of the motor. Here the average voltage given or the average current flowing through the motor will change depending on the ON and OFF time of the pulses controlling the speed of the motor.

EMBEDDED SYSTEMS Definition for : - EMBEDDED SYSTEMS Ø A combination of hardware and software which together form a component of a larger machine. Ø An example of an embedded system is a microprocessor that controls an automobile engine. Ø An embedded system is designed to run on its own without human intervention, and may be required to respond to events in real time.

EMBEDDED SYSTEMS

Contents Introduction Block diagram Hardware requirements Power supply Opto isolator Hall sensor Bldc motor Schematic diagram Working of the project Advantages Applications Conclusion

BLOCK DIAGRAM

Hardware requirements TRANSFORMER (230 – 12 V AC) VOLTAGE REGULATOR (LM 7805) MICROCONTROLLER (AT 89 S 52/AT 89 C 51) PUSH BUTTONS LCD 1 N 4007 LED RESISTOR CAPACITOR MC 2 TE OPTO ISOLATOR HALLSENSOR BLDC MOTOR BC 547

Hardware Components description 1. 230 V AC 50 Hz 2. Using In 4007 as Bridge rectifier 12 V step down transformer 3. Capacitors Filter(470µf) 4. 5 v Regulator 5. Relay

6. Push Buttons 8. IR LED 7. OPTO-ISOLATOR

9. RESISTOR 10. LED

11. Capacitor 12. PHOTODIODES 13. MOSFET

Power supply

Description of power supply ØThe circuit uses standard power supply comprising of a step-down transformer from 230 v to 12 v and 4 diodes forming a Bridge Rectifier that delivers pulsating dc which is then filtered by an electrolytic capacitor of about 470 microf to 100 micro. F. ØThe filtered dc being un regulated IC LM 7805 is used to get 5 v constant at its pin no 3 irrespective of input dc varying from 9 v to 14 v. ØThe regulated 5 volts dc is further filtered by a small electrolytic capacitor of 10 micro f for any noise so generated by the circuit. ØOne LED is connected of this 5 v point in series with a resistor of 330 ohms to the ground i. e. negative voltage to indicate 5 v power supply availability.

Block diagram of mc External interrupts Interrup t Control On-chip ROM for program code Timer/Counter On-chip RAM Timer 1 Timer 0 CPU OSC Bus Control 4 I/O Ports P 0 P 1 P 2 P 3 Address/Data Serial Port Tx. D Rx. D Counter Inputs

Microcontroller(at 89 s 52) • • Compatible with MCS®-51 Products • • 8 K Bytes of In-System Programmable (ISP) Flash Memory • – Endurance: 10, 000 Write/Erase Cycles • • 4. 0 V to 5. 5 V Operating Range • • Fully Static Operation: 0 Hz to 33 MHz • • Three-level Program Memory Lock • • 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 o • Fast Programming Time

PIN DIAGRAM OF AT 89 S 52

Opto-isolator ØOpto coupler is a 6 pin IC. It is a combination of 1 LED and a transistor ØPin 6 of transistor is not generally used and when light falls on the Base-Emitter junction then it switches and pin 5 goes to zero. IR LED An IR LED, also known as IR transmitter, is a special purpose LED that transmits infrared rays in the range of 760 nm wavelength. They, along with IR receivers, are commonly used as sensors.

PHOTODIODES In this mode the diode is often reverse biased, dramatically reducing the response time at the expense of increased noise. The reverse bias induces only a small amount of current (known as saturation or back current) along its direction while the photocurrent remains virtually the same. MOSFET The metal–oxide–semiconductor field-effect transistor (MOSFET, MOS-FET, or MOS FET) is a device used for amplifying or switching electronic signals. The channel can be of n-type or p-type and is accordingly called an n. MOSFET or a p. MOSFET.

BLDC motors Brushless DC motors also known as electronically commutated motors are synchronous electric motor powered by direct current(DC) electricity and having electronic commutation systems, rather than mechanical commutator and brushes. A BLDC motor has permanent magnets which rotate and a fixed armature, eliminating the problems of connecting current to the moving armature.

BLDC motors develop maximum torque when stationary and have linearly decreasing torque with increasing speed as shown in the adjacent

LIQUID CRYSTAL DISPLAY (LCD) ØMost common LCDs connected to the microcontrollers are 16 x 2 and 20 x 2 displays. ØThis means 16 characters per line by 2 lines and 20 characters per line by 2 lines, respectively. ØThe standard is referred to as HD 44780 U, which refers to the controller chip which receives data from an external source (and communicates directly with the LCD.

LCD BACKGROUND ØIf 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) ØThe three control lines are referred to as EN, RS, and RW ØEN=Enable (used to tell the LCD that you are sending it data) ØRS=Register Select (When RS is low (0), data is treated as a command) (When RS is High(1), data being sent is text data ) ØR/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)

BIBILOGRAPHY Ø “The 8051 Microcontroller and Embedded systems” by Muhammad Ali Mazidi and Janice Gillispie Mazidi , Pearson Education. Ø ATMEL 89 S 52 Data Sheets. • www. atmel. com • www. beyondlogic. org • www. wikipedia. org • www. howstuffworks. com • www. alldatasheets. com

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