Tuesday, June 2, 2015

Day 24 05/28/2015 Signals with Multiple Frequency Components

Class Note





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Circuit build

Pre-Lab
 This lab today is to aply different signals with multiple frequency components. The circuit consisted of 1kohm and series with and capacitor and also parallel to another 1kohm resistors

In the prelab we calculate the magnitude that response to the circuit. we know the s = jw and we simply it to get 1 / (RCS +2)
We first created a custom waveform 20(sin(1000πt)+sin(2000πt)+sin(20,000πt)) and sinusoidal sweep function.


20(sin(1000πt)+sin(2000πt)+sin(20,000πt)) function
At this graph we can see the high frequency part is more suppressed than the low frequency part.


500 Hz


1000 Hz


10,000 Hz


sinusoidal sweep
This one we see that frequency is being suppressed more .


Also being suppressed a lot here


As what we know from handout when the lower frequencies, the capacitor has infinite impedance, the circuit becomes a simple voltage divider which will simply divide income voltage half.

w = 0 => Vout/ vin = 1/2

However right now we were playing a high frequencies, but we didn't get our Independence to zero . our capacitor didn't act like short circuit. 

w = infinite => Vout/Vin =0

Summary: what I learned today is how frequency response. The frequency response the circuit is determined by the depend on the transfer function H(w) . The frequency dependent ratio of a phasor output to phasor input . 

Important function:




Day 23 05/26/2015 (Missed day the only day miss the class...) ( Data from classmate)


Today they supplied the AC supply to a resistor in series to inductor and resistor.
They do this lab to show the use of apparent power and power factor to quantify the AC power delivers to the load.


They first detail list all the components and the result of their pre-lab
The result of their resistance in series is changed each time.

10 ohm


47 ohm.


1000 ohm


Circuit.

This lab new required to include a capacitor in parallel with load. This can get the voltage being measured to be more in phase.

10Ω

47Ω

100Ω

This lab I learned the apparent power and power factor. we can see that the power is product the rms values of voltage and current and is in unit of voltage amperes. I see the power are cosine phase different between voltage and current. No cosine seems to be found. This lab kind help me able to calculate th AC power delivers to the load.