Page 275 - L . V S W I T C H G E A R

intelligent
Power factor

To discourage energy wastage, some ƉŽǁĞƌ ĨĂĐƚŽƌ ĐŽƌƌĞĐƟŽŶ ŶĞĞĚƐ ĐŚĂŶŐĞ
ĞůĞĐƚƌŝĐŝƚLJ ĚŝƐƚƌŝďƵƟŽŶ ĐŽŵƉĂŶŝĞƐ ƉĞ- ĨƌĞƋƵĞŶƚůLJ͘ ƵƚŽŵĂƟĐ ĐĂƉĂĐŝƚŽƌ ƐLJƐƚĞŵƐ
nalize consumers with a power factor ĂƌĞ ƐƵŝƚĂďůĞ ĨŽƌ ƐƵĐŚ ĨĂĐŝůŝƟĞƐ͖ ƐƵĐŚ ƐLJƐ-
ƚŚĂƚ ŝƐ ďĞůŽǁ Ă ƐƉĞĐŝĮĞĚ ǀĂůƵĞ͕ ĂŶĚ ŽīĞƌ tems prevent both over- and under-cor-
ĂŶ ŝŶĐĞŶƟǀĞ ƚŽ ĐŽŶƐƵŵĞƌƐ ǁŝƚŚ Ă ŐŽŽĚ ƌĞĐƟŽŶ͘
ƉŽǁĞƌ ĨĂĐƚŽƌ ;ƵƐƵĂůůLJ ĂďŽǀĞ Ϭ͘ϵϱͿ͘ dŚŝƐ >ĂƌŐĞ ŝŶĚƵĐƟǀĞ ůŽĂĚƐ ƐƵĐŚ ĂƐ Žŝů ĚƌŝůůŝŶŐ
encourages consumers to install power rigs, wind turbines, large motors, arc
ĨĂĐƚŽƌ ĐŽƌƌĞĐƟŽŶ ĞƋƵŝƉŵĞŶƚ ŝŶ ƚŚĞŝƌ furnaces, and auto crushers have dy-
ĞůĞĐƚƌŝĐĂů ƐLJƐƚĞŵƐ͘ ĞŶĞĮƚƐ ŽĨ ĂĚĚŝŶŐ ŶĂŵŝĐ ůŽĂĚ ĐŚĂƌĂĐƚĞƌŝƐƟĐƐ͘ ^ƵĐŚ ůĂƌŐĞ
ƉŽǁĞƌ ĨĂĐƚŽƌ ĐŽƌƌĞĐƟŽŶ ĐĂƉĂĐŝƚŽƌƐ ƚŽ ĚLJŶĂŵŝĐ ůŽĂĚƐ ĚĞŵĂŶĚ ƐŽƉŚŝƐƟĐĂƚĞĚ
electricity networks include reduced ĂƵƚŽŵĂƟĐ ĐĂƉĂĐŝƚŽƌ ƐLJƐƚĞŵƐ ǁŝƚŚ ĨĂƐƚ
losses, improved voltage, increased sys- ƌĞƐƉŽŶƐĞ ĐĂƉĂďŝůŝƟĞƐ͘ dƌĂŶƐŝĞŶƚͲĨƌĞĞ
ƚĞŵ ĐĂƉĂĐŝƚLJ͕ ĂŶĚ͕ ĂƐ ŵĞŶƟŽŶĞĚ ĂďŽǀĞ͕ ĂƵƚŽŵĂƟĐ ĐĂƉĂĐŝƚŽƌ ďĂŶŬƐ ĂƌĞ ƵƐĞĚ
reduced electricity bills. ĨŽƌ ƉŽǁĞƌ ĨĂĐƚŽƌ ĐŽƌƌĞĐƟŽŶ ŝŶ ĂƉƉůŝĐĂ-
<ĞLJ ǀĂƌŝĂďůĞƐ ƚŽ ĐŽŶƐŝĚĞƌ ǁŚĞŶ ƐĞůĞĐƟŶŐ ƟŽŶƐ ǁŚĞƌĞ ůĂƌŐĞ ŝŶĚƵĐƟǀĞ ůŽĂĚƐ ĂƌĞ
ĐĂƉĂĐŝƚŽƌƐ ĨŽƌ ƉŽǁĞƌ ĨĂĐƚŽƌ ĐŽƌƌĞĐƟŽŶ ŝŶǀŽůǀĞĚ͘ ,ĂƌŵŽŶŝĐƐ ĐĂŶ ƐŝŐŶŝĮĐĂŶƚůLJ
include load type, load constancy, load reduce the life of these capacitor banks.
ƐŝnjĞ͕ ůŽĂĚ ĐĂƉĂĐŝƚLJ͕ ŵĞƚŚŽĚ ŽĨ ƵƟůŝƚLJ For loads that produce harmonics, a
ďŝůůŝŶŐ͕ ĂŶĚ ůŽĂĚ ƐƚĂƌƟŶŐ ŵĞƚŚŽĚƐ͘ ŚĂƌŵŽŶŝĐ ĮůƚĞƌ ƐŚŽƵůĚ ďĞ ĂĚĚĞĚ͘ dŚŝƐ
WŽǁĞƌ ĨĂĐƚŽƌ ĐŽƌƌĞĐƟŽŶ ĐĂƉĂĐŝƚŽƌƐ ĂƌĞ ĮůƚĞƌ ƌĞŵŽǀĞƐ ƵŶǁĂŶƚĞĚ ŚĂƌŵŽŶŝĐ ĨƌĞ-
usually installed as banks of capacitors quencies from the electrical system.
ǁŚĞŶ ƐƵďƐƚĂƟŽŶƐ Žƌ ůĂƌŐĞ ĨĂĐŝůŝƟĞƐ ĂƌĞ
involved. In the case of sinusoidal or
linear loads, they can be installed as in-
p
dividual capacitors. Individual capacitors
nd do not
are easy to install or replace, and do not
ƉĂĐŝƚŽƌ
ƌĞƋƵŝƌĞ ƐĞƉĂƌĂƚĞ ƐǁŝƚĐŚŝŶŐ͘ ĂƉĂĐŝƚŽƌ
ƌ ŚĂŶĚ͕
ďĂŶŬ ŝŶƐƚĂůůĂƟŽŶƐ͕ ŽŶ ƚŚĞ ŽƚŚĞƌ ŚĂŶĚ͕
ŚĂǀĞ ůŽǁĞƌ ĐŽƐƚ ƉĞƌ Ŭs Z͕ ĂŶĚ ƉƌŽǀŝĚĞ
ƉƌŽǀŝĚĞ
ĐĂƉĂĐ-
ĞdžĂĐƚ ƉŽǁĞƌ ĨĂĐƚŽƌ ĐŽƌƌĞĐƟŽŶ ĐĂƉĂĐ-
ŝŶŐ ƐLJƐ-
ŝƚĂŶĐĞ ǁŚĞŶ ĂƵƚŽŵĂƟĐ ƐǁŝƚĐŚŝŶŐ ƐLJƐ-
tems are used.
Depending on the needs of a substa-
substa-
ŵĂƟĐĂůůLJ
ƟŽŶ Žƌ Ă ĨĂĐŝůŝƚLJ͕ ĮdžĞĚ Žƌ ĂƵƚŽŵĂƟĐĂůůLJ
be in-
switched capacitor banks can be in-
ĂƉĂĐŝƚŽƌ
ƐƚĂůůĞĚ͘ ĮdžĞĚ ƉŽǁĞƌ ĨĂĐƚŽƌ ĐĂƉĂĐŝƚŽƌ
bank can be switched on
ǁŚĞŶ ƚŚĞ ŝŶĚƵĐƟǀĞ ůŽĂĚ ŝƐ
ŽŶ͕ ĂŶĚ ƐǁŝƚĐŚĞĚ Žī ǁŚĞŶ
ƚŚĞ ŝŶĚŝǀŝĚƵĂů ůŽĂĚ ŝƐ Žī͘
Such capacitors are en-
ergized only when power
ĨĂĐƚŽƌ ĐŽƌƌĞĐƟŽŶ ŝƐ ŶĞĞĚĞĚ͘
/Ŷ ĨĂĐŝůŝƟĞƐ ǁŝƚŚ ŵƵůƟƉůĞ
ůŽĂĚƐ͕ ůŽĂĚ ĐŽŶĚŝƟŽŶƐ ĂŶĚ

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