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One is for motors that have to be kept turning but have loads on them for short time periods. Drilll presses are one example. There are circuits to correct the power factor during no load conditions.
The other is industrial where a capacitor is placed across the line at the input to the building. The factor is rarely corrected more than to 0.8 because of the circulating currents produce losses. For very big applications the capacitor bank is replaced by a rotating machine without a load and whose field coil has a controlled magnitude and phase of current.