Question

A single-phase motor is modeled as a resistor $R$ in series with an inductor $L$ as shown in Eigure P3.121. The capacitor corrects the power factor between terminals $a$ and $b$ to unity. Assume the meters shown are ideal and $f=50 \mathrm{~Hz}$, $V=220 \mathrm{Vrms}, I=20 \mathrm{~A} \mathrm{rms}$, and $I_1=25 \mathrm{~A} \mathrm{rms}$. Find the capacitor value. Figure P3.121 

   A single-phase motor is modeled as a resistor $R$ in series with an inductor $L$ as shown in Eigure P3.121. The capacitor corrects the power factor between terminals $a$ and $b$ to unity. Assume the meters shown are ideal and $f=50 \mathrm{~Hz}$, $V=220 \mathrm{Vrms}, I=20 \mathrm{~A} \mathrm{rms}$, and $I_1=25 \mathrm{~A} \mathrm{rms}$. Find the capacitor value.
Figure P3.121
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Principles and Applications of Electrical Engineering
Principles and Applications of Electrical Engineering
Giorgio Rizzoni,… 7th Edition
Chapter 3, Problem 121 ↓
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A single-phase motor is modeled as a resistor $R$ in series with an inductor $L$ as shown in Eigure P3.121. The capacitor corrects the power factor between terminals $a$ and $b$ to unity. Assume the meters shown are ideal and $f=50 \mathrm{~Hz}$, $V=220 \mathrm{Vrms}, I=20 \mathrm{~A} \mathrm{rms}$, and $I_1=25 \mathrm{~A} \mathrm{rms}$. Find the capacitor value. Figure P3.121
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Transcript

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00:01 I can write the value of theta m as minus 10 inverse 8 by 6 which is equal to minus 53 .13 degree.
00:11 Here theta m minus theta a is equal to 90 degree.
00:15 So theta a is equal to minus 53 .13 .13 degree minus 90 degree which is equal to minus 143 .13 .13 degree...
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