Design and programing of Relay Menu

Interfacing LCD And Keyboard

Design and Simulation of ZCD

Design and Simulation of Measurement of Voltage Magnitude

8

80

100

100

7

40

90

100

0 0

35

85

5

40

75

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27TH JAN 15TH FEB 1ST MAR 15TH MAR

PROJECT PROGRESS

PF V and I MHO Total

• Interfacing of LCD.

• Interfacing of Keyboard.

• ON/OFF Control.

• Reset.

• Menu.

• UP/DOWN/LEFT/RIGHT for navigation.

• Menu Consist of

• MTA Setting.

• Zone 1, Zone 2, Zone 3 impedance setting.

4/14/2014Electrical Department PES University

• Zero crossing detector(ZCD) is a voltage comparator that switches the output between +Vsat and –Vsat when the input crosses zero reference voltage.

• Working of ZCD can be easily understood if you know the working of a basic op amp comparator.

• In ZCD, we are setting one of the inputs as zero i.e. zero reference voltage.

• The output is driven into –Vsat when the input signal passes through zero to positive direction.

• Conversely, when input signal passes through zero to negative direction, the output switches to +Vsat.

4/14/2014Electrical Department PES University

4/14/2014Electrical Department PES University

Multisim 13 VBB StudioProteus 8

4/14/2014Electrical Department PES University

4/14/2014Electrical Department PES University

4/14/2014Electrical Department PES University

• Output wave from ZCD for Current input is square wave with 50Hz frequency

• Output wave from ZCD for Voltage input is square wave with 50Hz frequency

• Output magnitude of ZCD is equal to VCC (3.56v, 5v, 12v)

4/14/2014Electrical Department PES University

• Current sensor is used to get corresponding voltage output and wave.

• From the output wave we will get current zero crossing and magnitude.

4/14/2014Electrical Department PES University

• High voltage is converted into low voltage by step down transformer.

• Analog voltage converted into Digital by ADC.

• Voltage magnitude is found by sampled digital value.

4/14/2014Electrical Department PES University

• From the ZCD we will get square wave for current and voltage zero crossing.

• The time gap between this 2 output wave of ZCD is found.

• From the time interval Power factor is calculated.

4/14/2014Electrical Department PES University