Txoj cai ntawm Switching Power Supply Surge Protection
Surge Protective Device (SPD), tseem hu ua Surge Protector, yog ib qho khoom siv tiv thaiv uas tsis yog siv nyob rau hauv cov tshuab nyob kom txwv tsis pub dhau qhov hluav taws xob dhau mus thiab qhia tawm qhov hluav taws xob tam sim no. Nws yog siv los tiv thaiv hluav taws xob lossis hluav taws xob uas tsis tshua muaj hluav taws xob tiv thaiv qib los ntawm xob laim ntaus, electromagnetic pulses lossis kev ua haujlwm overvoltage puas. Nyob rau hauv xyoo tas los no, hluav taws xob cov ntaub ntawv xov xwm (xws li TV, xov tooj, kev sib txuas lus, computer network, thiab lwm yam) tau tsim sai heev, thiab cov khoom siv hluav taws xob ntau tau tshwm sim thiab nrov. Cov hom tshuab thiab cov cuab yeej siv no feem ntau kim thiab tseem ceeb, nrog rau kev ua haujlwm tsis tshua muaj hluav taws xob thiab tiv taus qhov hluav taws xob, ua rau lawv muaj kev cuam tshuam rau xob laim hluav taws xob pulses. Yog li, SPD yuav tsum tau siv rau kev tiv thaiv overvoltage.
Lub hauv paus ntsiab lus ua haujlwm ntawm SPD
Lub surge protector yog tsim rau kev tiv thaiv ntawm 220/380V low-voltage fais fab mov thiab yog ib tug nonlinear tivthaiv. Raws li IEC cov qauv, lub surge protector yog ib qho cuab yeej siv los tswj cov overvoltage thiab overcurrent ntawm cov kab sib kis. Lub hauv paus yuav tsum tau rau ib tug surge protector los ua ib tug tiv thaiv lub luag hauj lwm yog kom tiv taus lub teeb pom kev zoo tam sim no thiab zoo tua hluav taws xob zaus tam sim no generated tom qab lub xob laim ntws los ntawm lub siab tshaj plaws clamping voltage ntawm lub surge. Nws txwv qhov tam sim no overvoltage uas nkag mus rau hauv txoj kab hluav taws xob lossis cov teeb liab xa mus rau qhov hluav taws xob ntau yam uas cov khoom siv lossis lub kaw lus tuaj yeem tiv taus, lossis tso tawm hluav taws xob muaj zog rau hauv av los tiv thaiv cov cuab yeej tiv thaiv lossis kev puas tsuaj los ntawm kev cuam tshuam.
Hom thiab cov qauv ntawm surge protectors sib txawv raws li lawv cov kev siv sib txawv, tab sis lawv muaj tsawg kawg yog ib qho kev txwv tsis pub muaj hluav taws xob. Feem ntau siv surge protectors muaj xws li MOVs (MetalOxideVaristors) thiab gas paug hlab. Cov hluav taws xob muaj zog muaj zog thiab tsis tuaj yeem nres. Vim li no, lub tswv yim los tiv thaiv cov khoom siv hluav taws xob tsis zoo los ntawm kev puas tsuaj yog los hloov cov surge ntawm cov khoom siv thiab ces ntws mus rau hauv av.
Lub surge protector MOV muaj peb ntu: cov khoom siv hlau oxide nyob rau hauv nruab nrab, txuas nrog ob lub semiconductors rau lub hwj chim mov thiab hauv av xaim. Thaum qhov tshwm sim tshwm sim, MOV tam sim ua nrog lub sijhawm teb ntawm 1-3 nanoseconds. Lub "V" hauv MOV yog rheostat. Thaum lub sijhawm teb, qhov kev tawm tsam ntawm MOV poob los ntawm nws cov nqi siab tshaj plaws mus rau yuav luag xoom ohms, thiab overcurrent ntws mus rau hauv av los ntawm MOV. Cov cuab yeej tiv thaiv hluav taws xob txuas ntxiv ua haujlwm ntawm qhov kev ua haujlwm ib txwm muaj. Nws cov khoom siv hluav taws xob semiconductor muaj cov cuab yeej hloov pauv hloov nrog qhov hloov pauv voltage. Thaum qhov hluav taws xob poob qis dua tus nqi tshwj xeeb, kev txav ntawm cov hluav taws xob hauv ib lub semiconductor ua rau muaj kev tiv thaiv siab. Ntawm qhov tsis sib xws, thaum qhov hluav taws xob ntau tshaj qhov tshwj xeeb no, cov lus tsa suab ntawm cov hluav taws xob yuav hloov, thiab cov khoom siv hluav taws xob yuav txo qis rau zero ohms. Qhov voltage yog qhov qub, thiab lub zog tiv thaiv MOV tsis ua haujlwm ntawm sab, tsis cuam tshuam rau cov kab hluav taws xob.
Qhov taw qhia rau qhov zoo thiab qhov tsis zoo ntawm surge tiv thaiv cov cuab yeej (MOVs):
(1) Clamping voltage: sawv cev rau tus nqi hluav taws xob uas yuav ua rau MOV txuas rau hauv av xaim. Qhov qis dua qhov clamping voltage, qhov kev tiv thaiv zoo dua.
(2) Lub zog nqus / dissipation muaj peev xwm: Qhov nominal tus nqi sawv cev ntau npaum li cas lub zog tiv thaiv tuaj yeem nqus tau ua ntej raug hlawv, hauv joules. Tus nqi siab dua, qhov kev tiv thaiv zoo dua.
(3) Lub sij hawm teb: Cov tiv thaiv hluav taws xob tsis cuam tshuam tam sim ntawd, thiab yuav muaj kev ncua me ntsis hauv lawv cov lus teb rau kev nce siab.
Lwm cov cuab yeej tiv thaiv kev tiv thaiv kev kub ntxhov yog lub raj xa hluav taws xob. Cov roj tso tawm cov raj no muaj qhov ua haujlwm zoo ib yam li MOVs, txav dhau tam sim no los ntawm cov xaim nyob rau hauv av xaim, thiab ua tiav txoj haujlwm no los ntawm kev siv cov roj inert ua tus neeg xyuas pib ntawm ob lub xov hlau. Thaum qhov hluav taws xob nyob rau hauv ib qho tshwj xeeb, qhov sib xyaw ntawm cov roj txiav txim siab tias nws yog tus neeg xyuas pib tsis zoo. Yog hais tias qhov hluav taws xob surges thiab tshaj qhov no, lub zog ntawm tam sim no yuav txaus ionize cov roj, ua rau cov pa tawm tube yog ib tug zoo heev conductor. Nws yuav ua tam sim no rau hauv av xaim kom txog thaum qhov hluav taws xob rov qab mus rau qib qub, thiab tom qab ntawd dhau los ua tus neeg xyuas pib tsis raug.
