How can the power factor depend on the current and changing the power factor and what is the effect on the current?

In a limited way, the power factor reflects the quality of the power system. The load on the system is mostly inductive due to the large presence of motors, transformers, welding machines, lighting loads, etc. These devices have a large component of current in the system to maintain magnetizing current. This reactive current component does not participate in active work or power consumption. The actual power in the KW is a part of the KVA (apparent power) that is injected into the system. The ratio of apparent power to this kW is called the power factor.

So you can imagine that the power factor is less, more for a given load. Lower power factor also means the generator and transmission lines carry this additional current. This is for using the system at low efficiency, and if the power factor is improved, the current capacity of the system can serve a much higher load.

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