Mai suna Voltage Surge?

Maa shi Voltage Surge?

Takaitaccen

Voltage surge tana da ita ce yawan tsarin kwaikwayo na voltage wanda ya fi kusa da jirgin abincin kamar gida. Overvoltages a gasar kwaikwayon sun haɗa ne saboda yawan tsari daga ɗaya zuwa ɗaya ko daga ɗaya zuwa ground. Voltage surges suna cikin duwatsu na biyu na mafi girma: internal da external voltages.

Abun hawa Voltage Surges

Overvoltages a gasar kwaikwayon zai iya faruwa saboda matsalolin da suka faruwa a cikin ko saboda matsalolin atmospheric. Daga masu asalin overvoltages, voltage surges suna cikin duwatsu na biyu na mafi girma:

• Internal Overvoltage

• External Overvoltage

Internal Overvoltage

Idan voltage a cikin gasar kwaikwayo ya fi kusa da tsari ta da yake, ana kiran shi a matsayin internal overvoltage. Internal overvoltages suna cikin transient, dynamic, ko stationary. Idan overvoltage wave ya kasance transient, frequency ta ba na nufin da frequency ta system daidai, kuma ya kasance waɗannan kofin daɗi.

Transient overvoltages suna faruwa saboda amfani da circuit breakers a lokacin switching of inductive ko capacitive loads. Suna faruwa kuma idan an rarrabe current da yawa ko idan ɗaya maimakon phase da insulated neutral ya kasance grounded.

Dynamic overvoltages suna faruwa a frequency ta system daidai kuma sun kasance waɗannan kofin daɗi. Suna faruwa idan generator ya kasance disconnected ko idan babban baki ɗaya na load ya kasance shed.

Stationary overvoltages suna faruwa a frequency ta system kuma sun kasance waɗannan lokaci mai tsawo, musamman kafin ya kasance ɗaya lafiya. Wadannan overvoltages suna faruwa idan earth fault a ɗaya line ya kasance waɗannan lokaci mai tsawo. Suna faruwa kuma idan neutral ya kasance grounded through an arc suppression coil, wanda ya faɗa overvoltage a healthy phases.

Waɗannan internal overvoltages suna iya kusa da uku zuwa bude da tsari ta normal phase - to - neutral peak voltage ta system. Amma, don abincin da suka samu insulation masu kyau, suna da sauri mai yawa.

Internal overvoltages suna faruwa saboda wasu abubuwa:

• Switching Operation on Unloaded Line: A lokacin switching operations, idan line ya kasance connected zuwa voltage source, travelling waves sun faruwa. Waɗannan waves sun charge line na kusa. A lokacin disconnection, voltage ta waves sun iya kusa zuwa magnitude ba ta kasance twice the supply voltage.

• Sudden Opening of Load Line: Idan load a line ya kasance removed, transient voltage of value e = iz0 sun faruwa. Haka, i ya nufin instantaneous value of the current a lokacin line opening, and (z0) ya nufin natural or surge impedance of the line. Transient overvoltage on the line ba na nufin da line voltage. Saboda haka, low - voltage transmission system ya kasance likely to experience overvoltages of the same magnitude da high - voltage system.

• Insulation Failure: Insulation breakdown between the line and the earth ana faruwa. Idan insulation ya kasance fail, potential at the fault point ya kasance drop from its maximum value to zero. Wannan ya faɗa negative voltage wave with a very steep front, in the form of surges, which propagate in both directions.

External Overvoltages

Overvoltages caused by atmospheric discharges, such as static discharges or lightning strokes, suna kiran shi a matsayin external overvoltages. External overvoltages suna faɗa stress significant a cikin insulation ta electrical equipment. Intensity of these voltages suna yawan da nature ta lightning event.

Intensity of lightning suna neman da yadda directly power line ya kasance struck. Yana iya kasance directly by the main discharge, directly by a branch or streamer, or due to induction from a lightning flash passing close to but not touching the line.

Installations a cikin gasar kwaikwayon suna cikin duwatsu na biyu. Ɗaya na biyu shine electrically exposed, meaning apparatus ya kasance directly subjected to overvoltages of atmospheric origin. Ɗaya na biyu shine electrically non - exposed and thus not affected by this type of overvoltage.