Given the circuit in Fig. 11.80, find Io and the overall complex power supplied.
Calculate the current
Answer to Problem 61P
The current
Explanation of Solution
Given data:
Refer to Figure 11.80 in the textbook.
The current
For load A,
The apparent power
The power factor
For load B,
The real power
The real power
For load C,
The real power
The power factor
Formula used:
Write the expression to find the complex power.
Here,
Write the expression to find the power factor
Here,
Write the expression to find the real power.
Write the expression to find the reactive power.
Write the expression to find the output voltage.
Calculation:
The given Figure 11.80 is redrawn as shown in Figure 1.
For load A:
Substitute
Substitute
Substitute
Substitute
As the power factor is leading, the load is capacitive. Therefore, the equation becomes,
For load B:
Substitute
As the load is capacitive, the power factor is leading. Therefore, the equation becomes,
For load C:
Substitute
Substitute
Rearrange the equation as follows,
Substitute
Substitute
In Figure 1, the load B and load C are connected in series. Therefore,
Substitute
The modified Figure is shown in Figure 2.
Substitute
Substitute
Apply Kirchhoff’s current law in Figure 2 to find the current
Substitute
Convert the equation from rectangular to polar form.
The overall complex power supplied by the source is,
Substitute
Conclusion:
Thus, the current
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Chapter 11 Solutions
Fundamentals of Electric Circuits
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