6 INTRODUCTIONAs we know that in three phase supply there are three phases i.e. R Y B, it is necessary that these three phases are in correct order.Phase sequence detection system has been specifically designed keeping in mind an essential point of detection of correct phase.It is useful to connect any machine to the supply.
7 OBJECTIVEThe main purpose of this project is to detect the phase sequence of any machine which works on three phase supply.The other prospect of our topic is to control the supply voltage.To control the system from under voltage and over voltage.
8 BLOCK DIAGRAM OF PHASE SEQUENCE DETECTION ASTABLEMULTIVIBRATORDECADECOUNTERLEDARRAYFLIPFLOPPHASE SEQUENCEDETECTORRYBRYBBLOCK DIAGRAM OF PHASE SEQUENCE DETECTION
9 BLOCK DIAGRAM OF CONTROLLED POWER SUPPLY CONTINUE..BLOCK DIAGRAM OF CONTROLLED POWER SUPPLY
11 ASTABLE MULTIVIBRATOR Astable multivibrator is used to provide clock pulses to the counter.If the frequency is high the LED array ring is glowing too fast so that we can not find that whether the LED is glowing or not.
12 DECADE COUNTER AND LED ARRAYS IC 4017 represents decade counter which is used to run the led’s in a sequence.We are using 20 LED’s, in which 10 LED’s are green and the rest 10 LED’s are red.
13 PHASE SEQUENCE SENSOR & FLIP FLOP In the phase sequence and controlled power supply system the detection of phase occurs by the use of transistor.The property of D- flip flop is- The output is same as the input, means that if input is 1 than, output is also 1.
14 PHASE SEQUENCE DETECTOR A zener diode may function as a voltage regulator by acting as an accessory load, drawing more current from the source if the voltage is too high, and less if it is too low.
15 ABOUT THE PROJECTIt consists of IC4013 which is a D-flip flop and IC4017 which is a decade counter is used to run the LED’s in sequence.There are 20 LED’s , in which 10 LED’s glow in the clockwise direction when the phase sequence is correct and the rest 10 LED’s glow in the anti- clockwise direction when the phase sequence is incorrect.The green LED’s glow when the phase sequence is correct and the red LED’s glow when the phase sequence is incorrect.The decade counter counts 10 LED’s in a sequence.The astable multivibrator section provides clock pulses in 10 to 1000Hz range to the decade counter and the LED array section.The output of any three phase machine is fed to the input of this system. Now in the circuit there is arrangement of two transistor and the out put of the transistor is fed into the IC4013.
17 CONTINUE……..In case of over voltage, the voltage at the non-inverting terminal of op-amp rises but the voltage at inverting terminal remains at the same voltage due to zener diode.This causes relay to energize and disconnect the supply.In case of under voltage, the voltage at the inverting terminal falls below the voltage at the non-inverting terminal.This energizes the relay which disconnects the supply and protects the system from under voltage.