Hello everyone,
This is from a lab which we recently preformed at school and I'm confused about a few parts.
The first question relates to the first figure. (See figure attached)
When we preformed Experiment 2 and observed the current and voltage waveforms on the scope the current waveform was nonsinusoidal, but I'm not entirely sure why.
Is it because the current going through the core shunt branch is about 4050% of the rated current? Could this be why it's magnitude is almost 50%?
My second question relates to power and efficiency. (See second figure attached)
The first thing I am unsure of is how I calculated the stator copper losses.
I wrote,
\(P_{cu}(S) = 3I^{2}R_{s} = 23.97W\)
but I can't see to reproduce that number.
I was confused if I should use the \(R_{s}\) I calculated in the first part of the experiment(See first figure) or if I should calculate the value of \(R_{s}\) again using the table at the top of the second figure.
(i.e. \(R_{s} = \frac{V_{s}}{I_{s}} = \frac{117.7V}{0.88A}\)
Can someone clarify?
After this is sorted out we are asked to verify and confirm the above readings for the power, and thus the efficiency.
I attempted to calculate the rotor and stator losses using the values found in the first figure attached.
Note that we also have the rotational losses estimated in the second figure attached.
Are the calculations I've made for the rotor and stator losses correct? If so, how I reproduce the power and efficiency I've measured?
Thanks again!
This is from a lab which we recently preformed at school and I'm confused about a few parts.
The first question relates to the first figure. (See figure attached)
When we preformed Experiment 2 and observed the current and voltage waveforms on the scope the current waveform was nonsinusoidal, but I'm not entirely sure why.
Is it because the current going through the core shunt branch is about 4050% of the rated current? Could this be why it's magnitude is almost 50%?
My second question relates to power and efficiency. (See second figure attached)
The first thing I am unsure of is how I calculated the stator copper losses.
I wrote,
\(P_{cu}(S) = 3I^{2}R_{s} = 23.97W\)
but I can't see to reproduce that number.
I was confused if I should use the \(R_{s}\) I calculated in the first part of the experiment(See first figure) or if I should calculate the value of \(R_{s}\) again using the table at the top of the second figure.
(i.e. \(R_{s} = \frac{V_{s}}{I_{s}} = \frac{117.7V}{0.88A}\)
Can someone clarify?
After this is sorted out we are asked to verify and confirm the above readings for the power, and thus the efficiency.
I attempted to calculate the rotor and stator losses using the values found in the first figure attached.
Note that we also have the rotational losses estimated in the second figure attached.
Are the calculations I've made for the rotor and stator losses correct? If so, how I reproduce the power and efficiency I've measured?
Thanks again!
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