Hi all

Can anyone possibly explain what the differences between the following are:

Voltage stabilizers
Voltage regulation
Power factor correction units?

We run a large fabrication shop with five large welders and other power consuming devices.
From what I understand above, the power factor correction units, using capacitors even out the sin wave between reactive and active current flow.
Voltage regulators give one a even (constant current) similar to stabilizers.

But, in a factory (or shop, or even common household) one will be better or more suited than the other.

Anyone able to explain in layman's terms what the difference is?