Power factor correction allows you to calculate active, real, reactive power and phase angle. You will use the equation of a right triangle. So, to calculate angles you need to understand the laws of cosine, sine and tangent. You also need to know the Pythagorean law (c² = a² + b²) to be able to calculate the size of the sides of a triangle. In addition, you also need to know the unit/unit of each type of power. Active power is calculated in units called Volt-Amp-Reactive (VAR). There are several equations for calculating this problem and all of them will be discussed in this article. Now, you have a scientific basis for the problem to be calculated.
Step
Step 1. Calculate the impedance
(Think of it as if the impedance is in the same place as the active power in the figure above.) So to find the impedance, you need the Pythagorean Theorem c² = (a² + b²).
Step 2. Understand that Total Impedance (represented by the variable “Z”) is equal to the root of Real Power squared plus Reactive Power squared
(Z = (60² + 60²)). So, if you plug it into a science calculator, the answer is 84.85Ω (Z = 84.85Ω)
Step 3. Find the phase angle
Now you have the hypotenuse which is the impedance. You also have a side that is real power, while the other side is reactive power. So, to find the measure of an angle, you can use one of the laws mentioned earlier. For example, we use the law of Tangent, which is the opposite side divided by the side (reactive power / real power).
The equation will look like this: (60/60 = 1)
Step 4. Take the inverse of the tangent and get the Phase Angle
The inverse of the tangent is a button on the calculator. Now you take the inverse of the tangent from the previous step to get the phase angle. Your equation should look like this: tan (1) = Phase Angle. Thus, the answer is 45°.
Step 5. Calculate the total current (Amperes)
The unit for electric current is the ampere which is represented by the variable "A". The formula used to calculate current is Voltage (voltage) divided by Impedance, which based on the above example would look like this: 120V/84, 85Ω. Thus, you get an answer of 1,414A. (120V/84, 85Ω = 1,414A).
Step 6. Calculate the Active Power represented by the variable “S”
To calculate it, you need the Pythagorean Theorem because the hypotenuse is an impedance. Remember that the active power is calculated in Volt-Amp units so we can use the formula: Voltage squared divided by total impedance. The equation will look like this: 120V²/84, 85Ω so that the answer is 169, 71VA. (1202/84, 85 = 169, 71)
Step 7. Calculate the Real Power represented by the variable “P”
To calculate the real power, you need to find the current worked out in step four. Real power is calculated in Watts by multiplying the squared current (1, 141²) by the resistance (60Ω) in the electrical circuit. The answer obtained is 78, 11 Watts. Your equation should look like this: 1,414² x 60 = 119.96
Step 8. Calculate Power Factor
To calculate the power factor, you will need the following information: Watts and Volt-Amps. You have calculated both in the previous steps. Your Wattage is 78.11W and Volt-Amp is 169.71VA. The power factor formula (which is represented by the variable Pf) is Watt divided by Volt-Amp. Your equation should look like this: 119, 96/169, 71 = 0.707
You can also present your answer as a percentage by multiplying it by 100 so you get an answer of 70.7% (7.07 x 100)
Warning
- When calculating impedance, you use the inverse tangent function instead of just the regular tangent function in the calculator to get the exact phase angle.
- Here's a basic example of how to calculate the phase angle and power factor. There are more complicated electrical circuits that include capacitive power and higher resistance and reactance.
