Power factor correction unit
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An automatic power factor correction unit is equipment used to improve power factor. By increasing the power factor to near 1, current is reduced in the power system and usually utility charges for electrical power are reduced. A power factor correction unit usually consists of a number of capacitors that are switched by means of contactors. These contactors are controlled by a regulator that measures power factor in an electrical network. To be able to measure 'power factor', the regulator uses a CT (Current transformer) to measure the current in one phase.
Depending on the load and power factor of the network, the power factor controller will switch the necessary blocks of capacitors in steps to make sure the power factor stays above 0.9 or other selected values (usually demanded by the energy supplier).
Legend:
- Reactive Power Control Relay
- Network connection points
- Slow-blow Fuses
- Inrush Limiting Contactors
- Capacitors (single-phase or three-phase units, delta-connection)
- Transformer Suitable voltage transformation to suit control power (contactors, ventilation,...)
