{"id":714,"date":"2013-05-08T06:44:09","date_gmt":"2013-05-08T11:44:09","guid":{"rendered":"http:\/\/electricsaver1200.com\/blog\/?p=714"},"modified":"2017-02-25T14:30:49","modified_gmt":"2017-02-25T19:30:49","slug":"improve-power-factor-with-pfc-equipment","status":"publish","type":"post","link":"http:\/\/www.electricsaver1200.com\/blog\/improve-power-factor-with-pfc-equipment\/","title":{"rendered":"Improve Power Factor with PFC Equipment"},"content":{"rendered":"

\"\"Power Factor Correction<\/strong>
\nTransmission and distribution of electrical energy brings in the question of power factor improvement with the use of pfc equipments. Most of the loads are inductive hence giving a lagging power factor. A lagging power factor causes an increase in current. The increased current causes more power losses of active power. It is essential to have a power factor close to unity.
\nPower factor of an alternating circuit is the ratio of real power to the apparent power or the cosine of the angle between current and voltage of an alternating current circuit. Power factor is the ratio between resistances to the impedance of an AC circuit. There is a phase difference between current and voltage. The current lags behind the voltage in an inductive circuit while in a capacitive circuit the current leads the voltage.
\nThe value of the power factor is never more than one. It is good practice to attach the word leading or lagging when describing power factor.<\/p>\n

\"\"Demerits of low power factor<\/strong>
\nIncrease in the kVA rating of an equipment. A small power factor will mean a larger kVA rating of the equipment. This makes the equipment expensive and larger.
\nLow power factor means greater conductor size of the equipment
\nIt causes larger copper losses. This causes low efficiency
\nIt causes more voltage drop in transmission lines, transformers and alternators. This results in poor voltage regulation.
\nLow power factor results in a low handling capacity of the system.<\/p>\n

Causes of low power factor<\/strong>
\nMost ac motors are induction type. Induction type motors always have a lagging power factor. The motors work at very small power factors.
\nElectric discharge lamps, arc lamps and industrial heating furnaces work at very low power factors.
\nThere is varying load on a power system. The load is high in the morning\/evening and low during the rest of the day. At low loads, the voltage increases thus increasing the magnetization current. This leads to a low power factor.<\/p>\n

PFC Equipment<\/strong>
\nImprovement of low power factor is by the use of the following equipment.<\/p>\n

Static capacitors<\/strong>
\nPower factor correction is by connecting static capacitors in parallel with the equipment causing low power factor. The capacitors draw a leading current. They also neutralize the reactive component of the load current. Capacitor connection is by either in star or delta method.<\/p>\n

The static capacitors require little maintenance, and they have low losses.<\/p>\n