Measure phase angle by using an oscilloscope, Electrical Engineering

Assignment Help:

1. Introduction:

Theory:  Phase angle is defined as the number of degrees separating two sine waves of the same frequency. The Phase shift is defined as any change that occurs in the phase of one quantity, or in the phase difference between two or more quantities.

For infinitely long sinusoids, a change in Θ is the same as a shift in time, such as a time-delay.  If x (t) is delayed (time-shifted) by 1/4   of its cycle, it becomes:

1070_measure phase angle by using an oscilloscope.png

whose "phase" is now  Θ- (Π / 2)  It has been shifted by (Π / 2) radians.

Material Required: Oscilloscope, frequency generator, connecting wires, resistor, capacitor, potentiometer, multimeter.

Description and Aim: To measure phase angle by using an oscilloscope. The phase angle between two waveforms is calculated by ensuring that they are of same frequency. The amplitude can differ for both these waveforms. An input waveform will be passed through circuit which may make some changes in the phase of this waveform. Hence, the phase angle between the input and output waveforms is measured using the oscilloscope where one channel displays the reference waveform and other channel displays the second signal.

2. Method:

Step 1) First, make a circuit using a capacitor and a resistor. The potentiometer can also be used and turn it fully otherwise. The capacitor creates a phase shift in the waveform passing through it.

Step 2) Connect generator to phase angle circuit block. Using an oscilloscope, set generator for a sine wave output 6Vpk-pk at 1000 Hz.

Step 3) Connect channel 1 probe to input of the generator and channel 2 probe to output across C1. Ensure that oscilloscope trigger source control is set to channel 1. Switch from the vertical mode to ALT. Set ground references of both the channel to the graticule line. The phase angle between channel 1 and channel 2 is approximately zero at this moment.

Step 4) Slowly turn the potentiometer R2 completely clockwise. It makes the phase shift to right direction.

Step 5) Switch vertical mode to channel 1 and adjust time base and variable time base controls on oscilloscope so that one cycle of waveform is having exactly 8 divisions.

Step 6) Calculate phase angle between the two waveforms.

3. Results:

Frequency of waveform = 1000 Hz

V(pk-pk) = 6V

No of horizontal divisions for one cycle of waveforms = 8

Measure of one division = 45°

Phase angle  = 8 X 45° /  5  = 360° / 5   = 72°

(how did u get 5 in above line...mention that here)

4. Discussion:

Phase measurement of a waveform using oscilloscope is done. Prime source of error is resolution error, which is reduced by ensuring phase crossings align with ticks of oscilloscope.  If this experiment needs to be repeated for higher frequencies time step has to be properly changed to avoid quantization error.


Related Discussions:- Measure phase angle by using an oscilloscope

Why ce configuration is widely used in amplifier circuits, Q. Why CE config...

Q. Why CE configuration is widely used in amplifier circuits? The main ability of an transistor lies in amplifying weak signals. The transistor cannot alone perform this functi

Explain working of resistance-capacitance coupled amplifiers, Q. Explain wo...

Q. Explain working of Resistance-capacitance coupled Amplifiers? Resistance-capacitance (RC)-coupled  Amplifiers : The following figure illustrates the most widely used method

High pressure gas hazards, High Pressure Gas Hazards When we consider t...

High Pressure Gas Hazards When we consider the dangers of compressed gas in the lab, there are three main sources of danger as follows: 1) Sudden release of high pressure ga

What does the eu do, Execution Unit receives program instruction codes and ...

Execution Unit receives program instruction codes and data from BIU, implements these instructions and store the result in general registers.

Determine vout and the power supplied, Q. An operational amplifier stage is...

Q. An operational amplifier stage is typically represented by the circuit of Figure. For the values given, determine V out and the power supplied by the 2.5-V source.

Advantages and disadvantages of direct coupled coupling, Q. Mention the adv...

Q. Mention the advantages and disadvantages of direct coupled coupling?       Advantages:             1.Simple circuit due to minimum use of resistor             2.Low

Develop the equation of motion, Aloudspeaker is a common electrochemical tr...

Aloudspeaker is a common electrochemical transducer in which vibration is caused by changes in the input current to a coil which, in turn, is coupled to a magnetic structure that c

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd