Questions tagged [phasor]
The phasor tag has no summary.
183 questions
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I thought I understood electrical impedance. But apparently I don't
I've been an EE for a long time, and I thought I had a thorough understanding of impedance. I also know how to perform calculations using complex numbers, phasors, etc. But today I took a deeper dive ...
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2
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What is fault of this solution?
Correct answer is
V1 = 78 - j104
V2 = 72 + j104
V3 = 150 - j130
Q) Find the Voltage by mesh analysis
- 21
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1
answer
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Angle between line voltage and current, in power measurement using 2 wattmeters
After drawing all the phasors for an exercise involving power measurement in a balanced 3-phase AC circuit using two wattmeters, it becomes apparent that there is an angle of
\$ 30^\circ \pm \phi \$
...
- 75
0
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2
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Why initial condition is ignored in case of phasor integration?
Consider the following question from the book "Fundamentals of Electric Circuits" by Alexander and Sadiku:
It is solved in solution in this way:
But I can solve in a different way:
$$
v(t) ...
- 443
6
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2
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419
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Phase shift of a phase shifter circuit from "The art of Electronics"
In the book "The Art of Electronics" a phase shifter circuit is presented page 89:
The phase shift of the output voltage is defined as 2·atan(ωRC). When I calculate the phase I always get 1/(...
- 177
2
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3
answers
379
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How to Express a Complex Voltage Solution in the Time Domain
On mathforengineers.com/Problem2, I found the following problem:
So, the problem is to find the magnitude and phase shift of the voltage \$v_o\$.
I solved this on my own and got the same result as ...
0
votes
0
answers
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Space domain and phasor domain super-imposition in case of a 2 pole AC machine
I have been undergoing several doubts about the space-time relationship in an AC rotating machine but recently , I convinced myself that, due to the production of the RMF (rotating magnetic field ) , ...
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3
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Why do we need phasors for analysing signals and systems?
Phasor includes a real part as well as an imaginary part, in real domain the intuition is more clear, i.e we can use vectors instead to represent things, but to imagine a signal in a complex domain ...
- 109
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1
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AC Circuit Analysis: Mixing Complex and Real Voltages in KVL Equations
I'm doing this exercise (Exercise 7.21 in Fundamentals of Physics II by R. Shankar). It wants me to evaluate a circuit with an AC source series with DC source series with two parallel impedances. ...
3
votes
3
answers
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Why does phasor multiplication produce a different result with actual sine multiplication?
I thought phasors were shortcuts to the Euler's formula when dealing with sine functions.
For example,
$$\begin{align}\cos(t+a)+\cos(t+b)&=Re\{e^{j(t+a)}+e^{j(t+b)}\}\\
&=Re\{e^{jt}[(\cos a + \...
- 133
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AC Phasor Angles in Complex Number Analysis
I'm not sure if this problem is unique to me, but it's been breaking my brain for the past few months. While assuming phasor angles for AC circuit analysis using complex numbers, my teacher said that ...
0
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1
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When can we apply phasor analysis to an \$RLC\$ circuit?
This answer of mine shows that not every \$RLC\$ circuit reaches sinusoidal steady state at input frequency.
A well-known theorem states that:
If all natural frequencies of a uniquely solvable LTI ...
- 163
2
votes
4
answers
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How can I mathematically show that multiplication of j will cause a phase shift?
I have a simple question that I cannot seem to wrap my head around.
let's say I have a function Asin(wt), if I multiply a '-j' by this function to get:
-jAsin(w*t), I have been told that this is ...
- 548
0
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4
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AC Circuit Analysis - Mesh Analysis With Unknown Impedance Value
I attempted the problem below using mesh analysis, but I'm struggling to figure out how to solve and find the impedance Z. I feel like I'm forgetting something very basic, but I can't figure out what ...
- 103
1
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1
answer
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Why is clockwise KVL done like this?
My task is to find voltage across the resistor of this circuit where all the 4 components are connected in series with each other.
The given information are : V1 (t) = 100 * sin(100 * t) V, R = 100 ...
- 153