what is power factor in electricity?
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Imagine voltage and current flowing down a wire. In a purely resistive load the Voltage is in the vertical axis and the current is in the horizontal axis, such that if your where to draw it, it would resemble a string of beads (AC system). When Voltage is zero, current is zero. When Voltage is maximum, current is maximum.
The total volume inside of each bead is the power dissipated in the resistive load.
In a reactive load such as a motor, the winding inductance causes the current to rotate off the 90 degree and the string of beads is now kinda oval or squashed. The volume inside the oval is reduced. Power dissipated in the load is reduced.
The Power Factor (PF) represents the amount of squashy relative to a perfect bead. It’s a ratio so it has no units.
It is important to consider PF because to dissipate 600W into a reactive load vs dissipating 600W into a resistive load requires more power from the source.
Another problem is the current can rotate so much that it become in-phase with the voltage. The area of the bead drops to zero and no power is imparted into the load. This is used by inductors in blocking high frequency signals such as in speaker crossovers. But the voltage and current sum in phase and create a peak and this can exceed breakdown voltages in components or wire sheathing.
Finally something with a large Power Factor will also mean a large inrush current before the reluctance fields reach equilibrium, and this can exceed systems’ specs at startup.
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