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A delta-connected resistive load is connected to a three-phase power system and the total power dissipated by the load is 375 W. What is the power supplied by each phase of the power system assuming that the load is balanced?

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The power supplied by each phase of the power system is approximately 41.67 W.

In a balanced delta-connected resistive load, each resistor in the delta is equal, and the load is symmetrically distributed. When connected to a three-phase power system, the power supplied to each phase can be determined as follows:

Let P_total be the total power dissipated by the load, which is 375 W.

In a balanced three-phase system, the total power (P_total) is given by:

P_total = √3 * V_line * I_line * cos(θ)

where:

√3 is the square root of 3 (approximately 1.732),

V_line is the line voltage,

I_line is the line current, and

cos(θ) is the power factor.

In a delta-connected load, the line voltage (V_line) is the same as the phase voltage (V_phase).

So, for each phase:

P_phase = V_phase * I_line * cos(θ)

To find the power supplied by each phase, we need to determine the line current (I_line) and power factor (cos(θ)).

Since the load is resistive, the power factor (cos(θ)) is 1 (unity) for purely resistive loads.

Therefore, for each phase:

P_phase = V_phase * I_line * 1

P_phase = V_phase * I_line

Now, we need to determine the line current (I_line).

The total power (P_total) is given as 375 W. In a balanced three-phase system, the total power is equally distributed among the three phases. Therefore, the power supplied by each phase (P_phase) is one-third of the total power:

P_phase = P_total / 3

P_phase = 375 W / 3

P_phase = 125 W

Now, we have the power supplied by each phase (P_phase), and we know that P_phase = V_phase * I_line. Since the load is resistive, the power factor (cos(θ)) is 1, and we can assume the line voltage (V_phase) is constant for each phase.

Therefore, for each phase:

V_phase * I_line = 125 W

Since V_phase is the same for each phase, we can say:

V_phase * (I_line_phase1 + I_line_phase2 + I_line_phase3) = 125 W

For a balanced load, the line currents are equal in magnitude and 120 degrees apart in phase.

Let's assume the line current as I_line. Then:

I_line_phase1 + I_line_phase2 + I_line_phase3 = 3 * I_line

So, we can rewrite the equation as:

V_phase * 3 * I_line = 125 W

Now, we can solve for I_line:

I_line = 125 W / (3 * V_phase)

Finally, to find the power supplied by each phase (P_phase), we can substitute the value of I_line:

P_phase = V_phase * I_line

P_phase = V_phase * (125 W / (3 * V_phase))

P_phase = 125 W / 3

Therefore, the power supplied by each phase of the power system is approximately 41.67 W.

User Abdullah Al Fahad
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