In a power triangle, the power factor angle (also known as the phase angle) is the angle between the voltage (V) and the current (I) phasors. It represents the phase difference between the two quantities and indicates whether the load is predominantly resistive, inductive, or capacitive.
To calculate the power factor angle in a power triangle, you'll need to know the real power (P) and apparent power (S) of the electrical system. The real power is the actual power consumed by the load, while the apparent power is the total power supplied by the source to the load, considering both real and reactive power.
The power factor angle (θ) can be calculated using the following formula:
θ = cos^(-1)(P / S)
Where:
θ is the power factor angle in radians.
cos^(-1) is the inverse cosine function.
Here are the steps to find the power factor angle:
Step 1: Determine the real power (P) and apparent power (S) from the power triangle or the power measurements of the system.
Step 2: Divide the real power (P) by the apparent power (S).
Step 3: Take the inverse cosine (cos^(-1)) of the result from Step 2. This will give you the power factor angle in radians.
Step 4: If you need the power factor angle in degrees, convert the radians value to degrees by multiplying it by 180/π (approximately 57.3 degrees).
Keep in mind that the power factor angle can be positive for a capacitive load and negative for an inductive load. A positive angle indicates that the current leads the voltage, while a negative angle indicates that the current lags the voltage. A purely resistive load will have a power factor angle of 0, meaning the voltage and current are in phase with each other.