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Power factor intelligent
Principles and technologLJ of power factor
correcƟon (PFC) capacitors.
DŽƐƚ ĞůĞĐƚƌŝĐĂů ůŽĂĚƐ͕ ŝŶĐůƵĚŝŶŐ ƚƌĂŶƐ- ĂƌĞ ƵƟůŝnjŝŶŐ ƉŽǁĞƌ ĞĸĐŝĞŶƚůLJ͕ ǁŚŝůĞ
ĨŽƌŵĞƌƐ͕ ǁĞůĚŝŶŐ ƐĞƚƐ͕ ŝŶĚƵĐƟŽŶ a low power factor indicates that the
ŵŽƚŽƌƐ͕ ĂŶĚ ŝŶĚƵĐƟŽŶ ĨƵƌŶĂĐĞƐ ĂƌĞ ĐŽŶŶĞĐƚĞĚ ĞůĞĐƚƌŝĐĂů ůŽĂĚƐ ĂƌĞ ƵƟůŝnjŝŶŐ
ŝŶĚƵĐƟǀĞ͘ /ŶĚƵĐƟǀĞ ůŽĂĚƐ ƌĞƋƵŝƌĞ ďŽƚŚ ƉŽǁĞƌ ŝŶĞĸĐŝĞŶƚůLJ͘ ƉŽŽƌ ƉŽǁĞƌ ĨĂĐ-
working power, usually measured in ƚŽƌ ƌĞƐƵůƚƐ ŝŶ ƐŝŐŶŝĮĐĂŶƚ ĞŶĞƌŐLJ ǁĂƐƚ-
ŬŝůŽǁĂƩƐ ;ŬtͿ͕ ĂŶĚ ƌĞĂĐƟǀĞ ƉŽǁĞƌ͕ age, and decreases the capacity of the
usually measured in kilo-volt-am- electrical system. It can be caused by a
ƉĞƌĞƐͲƌĞĂĐƟǀĞ ;Ŭs ZͿ͕ ƚŽ ŽƉĞƌĂƚĞ͘ dŚĞ ƉŚĂƐĞ ĚŝīĞƌĞŶĐĞ ďĞƚǁĞĞŶ ĐƵƌƌĞŶƚ ĂŶĚ
working power is used for performing voltage at the terminals of an electrical
ƚŚĞ ĂĐƚƵĂů ǁŽƌŬ͕ ǁŚŝůĞ ƌĞĂĐƟǀĞ ƉŽǁĞƌ load or a distorted current waveform.
ŝƐ ƵƐĞĚ ĨŽƌ ƐƵƐƚĂŝŶŝŶŐ ƚŚĞ ŵĂŐŶĞƟĐ
ĮĞůĚ ƌĞƋƵŝƌĞĚ ďLJ ŝŶĚƵĐƟǀĞ ůŽĂĚƐ͘
When combined, working power and
ƌĞĂĐƟǀĞ ƉŽǁĞƌ ĨŽƌŵ ĂƉƉĂƌĞŶƚ ƉŽǁĞƌ͕
usually measured in kilovolt-amperes
;Ŭs Ϳ͘
WŽǁĞƌ ĨĂĐƚŽƌ ŝƐ Ă ŵĞĂƐƵƌĞ ŽĨ ƚŚĞ Ğĸ-
ciency with which electrical loads con-
vert electrical power into useful work.
/ƚ ŝƐ Ă ƌĂƟŽ ŽĨ ƵƐĞĨƵů ƉŽǁĞƌ ;ǁŽƌŬŝŶŐ
power) to the total power (apparent
ƉŽǁĞƌͿ ƐƵƉƉůŝĞĚ͘ ŚŝŐŚ ƉŽǁĞƌ ĨĂĐƚŽƌ
is an indicator that the electrical loads
Power Factor CorrecƟon SoluƟons
ƉŽŽƌ ƉŽǁĞƌ ĨĂĐƚŽƌ ĚƵĞ ƚŽ ŝŶĚƵĐƟŽŶ ĐŽŵƉĞŶƐĂƚĞ ƚŚĞ ůĂŐŐŝŶŐ ĐƵƌƌĞŶƚ͘ WŽǁĞƌ
motors, transformers, and other induc- ĨĂĐƚŽƌ ĐŽƌƌĞĐƟŽŶ ĐĂƉĂĐŝƚŽƌƐ ĂƌĞ ĚĞ-
ƟǀĞ ůŽĂĚƐ ŝƐ ĐŽƌƌĞĐƚĞĚ ďLJ ĐŽŶŶĞĐƟŶŐ signed to ensure that the power factor
suitable capacitors. On the other hand, ŝƐ ĂƐ ĐůŽƐĞ ƚŽ ƵŶŝƚLJ ĂƐ ƉŽƐƐŝďůĞ͘ ůƚŚŽƵŐŚ
a poor power factor that is caused by ƉŽǁĞƌ ĨĂĐƚŽƌ ĐŽƌƌĞĐƟŽŶ ĐĂƉĂĐŝƚŽƌƐ ĐĂŶ
distorted current waveform is corrected considerably reduce the burden caused
ďLJ ĂĚĚŝŶŐ ŚĂƌŵŽŶŝĐ ĮůƚĞƌƐ͘ dŚĞ ƉƌŽĐĞƐƐ ďLJ ĂŶ ŝŶĚƵĐƟǀĞ ůŽĂĚ ŽŶ ƚŚĞ ƐƵƉƉůLJ͕ ƚŚĞLJ
ŽĨ ĐƌĞĂƟŶŐ ƚŚĞ ŵĂŐŶĞƟĐ ĮĞůĚ ƌĞƋƵŝƌĞĚ ĚŽ ŶŽƚ ĂīĞĐƚ ƚŚĞ ŽƉĞƌĂƟŽŶ ŽĨ ƚŚĞ ůŽĂĚ͘
ďLJ ĂŶ ŝŶĚƵĐƟǀĞ ůŽĂĚ ĐĂƵƐĞƐ Ă ƉŚĂƐĞ LJ ŶĞƵƚƌĂůŝnjŝŶŐ ƚŚĞ ŵĂŐŶĞƟnjŝŶŐ ĐƵƌƌĞŶƚ͕
ĚŝīĞƌĞŶĐĞ ďĞƚǁĞĞŶ ƚŚĞ ǀŽůƚĂŐĞ ĂŶĚ ƚŚĞ capacitors help to cut losses in the elec-
ĐƵƌƌĞŶƚ͘ ĐĂƉĂĐŝƚŽƌ ĐŽƌƌĞĐƚƐ ƚŚĞ ƉŽǁĞƌ ƚƌŝĐĂů ĚŝƐƚƌŝďƵƟŽŶ ƐLJƐƚĞŵ͕ ĂŶĚ ƌĞĚƵĐĞ
factor by providing a leading current to the electricity bill.
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