Power Factor Correction and Harmonic Filtering

Power Factor Correction: Why?

When we have power flowing in electrical circuits, we can have three modes of current flow:

  • Current in phase with the voltage when the load is resistive (eg. electric heating element),
  • Current leading the voltage when the load is capacitive (eg. Compensation capacitors)
  • Current lagging the voltage when the load is inductive (eg. Induction motor)

The portion of the current in phase with the voltage is responsible for real power flow and the component which is out of phase with the voltage is responsible for reactive power.  The smaller the reactive power component, the better (i.e. closer to unity) the power factor of the installation is.

The utility gives a cheaper tariff for consumers who keep their reactive power as low as possible and therefore, any large consumer can benefit from a cheaper electricity tariff by keeping the power factor as close to unity as possible.

Power Factor Correction: How?

By installing a capacitor bank it is possible to reduce the reactive power absorbed by the inductive loads in the system and consequently the power factor improves.  It is suitable to have the power factor (cosφ) a little in excess of 0.95 to benefit from a cheaper electricity rate. cosφ must not be too close to unity, to avoid the capacitive working of the electrical system.

The choice of the correct power factor correction equipment depends on the type of loads present and by their way of working. The choice is between CENTRAL COMPENSATION and INDIVIDUAL COMPENSATION.

  • Individual compensation: power factor correction is sited at each single load (eg. motor terminals).
  • Central compensation: we install only one bank of capacitors to a main power distribution station or substation.

Renergy Limited can monitor your electricity demand and custom design a power factor correction solution for your needs which ensures the quickest pay-back and optimum reliability.  We work with top class manufacturers with over 30 years of experience in the manufacturing of capacitors and PFC units.  All units are CE marked and manufacturing is ISO9001. ISO14001 and OHSAS18001 certified.