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intelligent
Power factor
Power factor
In the Įrst we must know some edž- S сP +ũQ
pressions: AcƟve power: It’s the totallLJ PсPф90
power used in the electrical circuit QLсQLф90
resistance. QcсQcф-90
ReacƟve power: It’s absorbing or back- Cos ʔ сP/S
ing power bLJ coils or capacitance. Power factor с acƟve power / ap-
Apparent power: It’s the total power parent power
which used to feed the electrical cir-
cuit.
Edžist two categories of alternaƟng ac sLJstem loads:
ResisƟve Loads:
It’s the devices which consist of resistance only , the
ĂďƐŽƌďŝŶŐ ĐƵƌƌĞŶƚ ĐŽŶǀĞƌƚĞĚ ƚŽ ƚŚĞƌŵĂů Žƌ ůŝŐŚƟŶŐ
ǁŚŝĐŚ ƚŚĞ ǀŽůƚĂŐĞ ŝƐ ĐŽŶƐƚĂŶƚ ƐŽ ƚŚĞ ĂĐƟǀĞ ƉŽǁĞƌ с
the apparent power , in this case the power factor = 1
and the current and the voltage in the same phase .
InducƟve Loads:
ůů ŽĨ ŵŽƚŽƌ ĂŶĚ ƚŚĞ ƚƌĂŶƐĨŽƌŵĞƌƐ ĚĞƉĞŶĚ ŽĨ ƚŚĞ
DĂŐŶĞƟĐ ĐŚĂŶŐŝŶŐ ŶŽƚ ƚŚĞ ƉĞƌŵĂŶĞŶƚ͘
The necessary electric current to this purpose not
ĨƵůůLJ ƵƐĞĚ ͕ ĂŌĞƌ ƉƌŽĚƵĐŝŶŐ ƚŚĞ ŵĂŐŶĞƚ ƚŚĞ ĐƵƌƌĞŶƚ WhLJ improve power factor?
ďĂĐŬ ƚŽ ƚŚĞ ĞůĞĐƚƌŝĐ ƉƌŽĚƵĐƟŽŶ ƐƚĂƟŽŶ ĂŶĚ ĐĂůůĞĚ dŚĞ ďĞŶĞĮƚƐ ƚŚĂƚ ĐĂŶ ďĞ ĂĐŚŝĞǀĞĚ ďLJ ĂƉƉůLJŝŶŐ ƚŚĞ
;ZĞĂĐƟǀĞ WŽǁĞƌͿ ĂŶĚ ƚŚĞ ĐƵƌƌĞŶƚ ƚŚĂƚ ĐĂƌƌŝĞƐ ŽƵƚ ŝƚƐ ŽƌƌĞĐƚ ƉŽǁĞƌ ĨĂĐƚŽƌ ĐŽƌƌĞĐƟŽŶ ŝƐ͗
ǁŽƌŬ ĂŶĚ ŝƐ ĨƵůůLJ ƵƟůŝnjĞĚ ŝƐ ĐĂůůĞĚ ĂĐƟǀĞ ƉŽǁĞƌ ͘ ŽƐʔ
͗ dŽƚĂů ĚŝƌĞĐƟŽŶĂů Žƌ ƌĂƟŽ ďĞƚǁĞĞŶ ďŽƚŚ ĂĐƟǀĞ ĂŶĚ ŶǀŝƌŽŶŵĞŶƚĂů ďĞŶĞĮƚ͘ ZĞĚƵĐƟŽŶ ŽĨ ƉŽǁĞƌ
ƌĞĂĐƟǀĞ ƉŽǁĞƌ ƚŽ ƉƌŽĚƵĐĞ ƚŚĞ ĂƉƉĂƌĞŶƚ ƉŽǁĞƌ͘ ŽŶƐƵŵƉƟŽŶ ĚƵĞ ƚŽ ŝŵƉƌŽǀĞĚ ĞŶĞƌŐLJ ĞĸĐŝĞŶĐLJ͘
ZĞĚƵĐĞĚ ƉŽǁĞƌ ĐŽŶƐƵŵƉƟŽŶ ŵĞĂŶƐ ůĞƐƐ ŐƌĞĞŶŚŽƵƐĞ
To improvement ŐĂƐ ĞŵŝƐƐŝŽŶƐ ĂŶĚ ĨŽƐƐŝů ĨƵĞů ĚĞƉůĞƟŽŶ ďLJ ƉŽǁĞƌ
ƐƚĂƟŽŶƐ͘
the power factor : ZĞĚƵĐƟŽŶ ŽĨ ĞůĞĐƚƌŝĐŝƚLJ ďŝůůƐ
džƚƌĂ Ŭs ĂǀĂŝůĂďůĞ ĨƌŽŵ ƚŚĞ ĞdžŝƐƟŶŐ ƐƵƉƉůLJ
dŚĞ ĐĂƉĂĐŝƚĂŶĐĞ ŝƐ ƚŚĞ ŵŽƐƚ ƉƌĂĐƟĐĂů ĂŶĚ ĞĐŽŶŽŵŝ- ZĞĚƵĐƟŽŶ ŽĨ /ϮZ ůŽƐƐĞƐ ŝŶ ƚƌĂŶƐĨŽƌŵĞƌƐ ĂŶĚ ĚŝƐƚƌŝďƵ-
ĐĂůůLJ ǀŝĂďůĞ ĚĞǀŝĐĞ ƚŽ ŝŵƉƌŽǀĞ ŝƚ ͕ ƌĞĂĐƟǀĞ ƉŽǁĞƌ Žƌ ƟŽŶ ĞƋƵŝƉŵĞŶƚ
ŝŶĚƵĐƟǀĞ ƉŽǁĞƌ ƉƌŽĚƵĐĞĚ ĨƌŽŵ ƚŚĞ ŝŶĚƵĐƟǀĞ ůŽĂĚƐ ZĞĚƵĐƟŽŶ ŽĨ ǀŽůƚĂŐĞ ĚƌŽƉƐ ŝŶ ůŽŶŐ ĐĂďůĞƐ͘
, the capacitance produce a completely opposite džƚĞŶĚĞĚ ĞƋƵŝƉŵĞŶƚ ůŝĨĞ ʹ ZĞĚƵĐĞĚ
ƉŽǁĞƌ ĨŽƌ ƚŚĞŝƌ ĚĞĐĂLJ ͕ ĂŶĚ ĐĂůůĞĚ ĐĂƉĂĐŝƟǀĞ ƌĞĂĐƟǀĞ electrical burden on cables and
ƉŽǁĞƌ ͘ dŽ ƉƌĞǀĞŶƚ ƉĂƐƐ ƚŚĞ ƌĞĂĐƟǀĞ ĐƵƌƌĞŶƚ ďĞƚǁĞĞŶ electrical components.
ƚŚĞ ůŝŶĞƐ ďĞƚǁĞĞŶ ůŽĂĚ ĂŶĚ ƉŽǁĞƌ ƐƚĂƟŽŶ ͕ ĐŽŶŶĞĐƚ
the capacitance in series with the load as a storage
ĚĞǀŝĐĞ ĨŽƌ ƚŚĞ ƌĞĂĐƟǀĞ ĐƵƌƌĞŶƚ ͕ ƚŚĞ ƌĞĂĐƟǀĞ ĐƵƌƌĞŶƚ
ŝŶ ĐŽŶŶĞĐƟŽŶ ůŽĂĚ ĚŽŶ͛ƚ ďĂĐŬ ƚŽ ƉŽǁĞƌ ƐƚĂƟŽŶ ďƵƚ
to capacitance and trading between the capacitance
and load .
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