Concept explainers
The missing values.
Explanation of Solution
The given values are shown in below table:
Alternator (A) | Load 1 (L1) | Load 2 (L2) | Load 2 (L2) | ||||
480 | |||||||
P |
Refer to the circuit shown in Figure 7-21, all the both loads L1, L2, and L3 are connected to the alternator. Thus, the line voltages are equal.
Consider load 3:
Here, the load 3 is made by 3 capacitors and uses wye connection. In wye connection, the line voltage is equal to
Thus,
Calculate the phase current of the load 3
In wye connection, the phase current
Thus,
Here, the load 3 is pure capacitive, the voltage and current are 90° out of phase with each other. Thus, the power factor becomes zero.
Calculate the reactive power of load 3
Consider load 2:
Here, the load 2 is made by 3 inductors and uses delta connection. In delta connection, the line voltage is equal to phase voltage.
Calculate the phase current of the load 2
Calculate the line current of the load 2
Calculate the inductive power of load 2
Consider load 1:
Here, the load 1 is made by 3 resistors and uses wye connection. In wye connection, the line voltage is equal to
Thus,
Calculate the phase current of the load 1
Here, the load 1 is made by 3 resistors and uses wye connection. In wye connection, the line current is equal to phase current.
Calculate the resistive power of load 1
Consider the alternator:
Since, the alternator is connected to the loads such as resistive
Calculate the total current supplied by the alternator to the RLC circuit.
Here, the alternator uses wye connection. In wye connection, the line current is equal to phase current.
In wye connection, the line voltage is equal to
Thus,
Calculate the apparent power of alternator
Thus, the all missing values are calculated and shown in below table:
Alternator (A) | Load 1 (L1) | Load 2 (L2) | Load 2 (L2) | ||||
277.13 | 277.13 | 480 | 277.13 | ||||
33.49 | 23.09 | 30 | 27.71 | ||||
480 | 480 | 480 | 480 | ||||
33.49 | 23.09 | 51.96 | 27.71 | ||||
VA | 27843.06 | ||||||
P | 33255.36 | 43198.73 | 23040.16 |
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Chapter 7 Solutions
Electrical Transformers and Rotating Machines
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