{"id":1672,"date":"2025-12-03T16:36:33","date_gmt":"2025-12-03T08:36:33","guid":{"rendered":"https:\/\/www.northpwr.cn\/?p=1672"},"modified":"2025-12-03T16:37:20","modified_gmt":"2025-12-03T08:37:20","slug":"the-reason-for-the-heating-up-of-the-high-voltage-switchgear-when-it-is-energized","status":"publish","type":"post","link":"https:\/\/www.northpwr.cn\/cs\/industry-news\/the-reason-for-the-heating-up-of-the-high-voltage-switchgear-when-it-is-energized\/","title":{"rendered":"D\u016fvod zah\u0159\u00edv\u00e1n\u00ed vysokonap\u011b\u0165ov\u00e9ho rozv\u00e1d\u011b\u010de p\u0159i jeho zapnut\u00ed"},"content":{"rendered":"<div class=\"e_richText-63 s_title clearfix response-transition\">\n<p>Po kr\u00e1tk\u00e9m sezn\u00e1men\u00ed s vysokonap\u011b\u0165ovou rozv\u00e1d\u011b\u010dovou technikou a pozn\u00e1n\u00ed d\u016fvod\u016f zah\u0159\u00edv\u00e1n\u00ed vysokonap\u011b\u0165ov\u00e9 rozv\u00e1d\u011b\u010dov\u00e9 techniky p\u0159i jej\u00edm nap\u00e1jen\u00ed \u2013 nev\u00edm, jestli v\u00e1s to bude zaj\u00edmat? V\u011bnujeme se poskytov\u00e1n\u00ed nejkvalitn\u011bj\u0161\u00edch slu\u017eeb, poj\u010fme se na to pod\u00edvat.<\/p>\n<p>(1) Rozd\u00edln\u00e9 kovy maj\u00ed r\u016fzn\u00fd efekt rozta\u017enosti. Koeficient rozta\u017enosti kov\u016f u ocelov\u00fdch \u0161roub\u016f je mnohem men\u0161\u00ed ne\u017e u m\u011bd\u011bn\u00fdch a hlin\u00edkov\u00fdch sb\u011brn\u00fdch li\u0161t, zejm\u00e9na u spoj\u016f za\u0159\u00edzen\u00ed typu \u0161roubov\u00e9ho. P\u0159i zm\u011bn\u011b provozn\u00edho proudu a teploty doch\u00e1z\u00ed k odli\u0161n\u00e9mu stupni rozta\u017enosti a smr\u0161\u0165ov\u00e1n\u00ed hlin\u00edku \u010di m\u011bdi a \u017eeleza, co\u017e zp\u016fsobuje plazen\u00ed, tedy pomal\u00e9 plastick\u00e9 deformaci kovu p\u016fsoben\u00edm nam\u00e1h\u00e1n\u00ed. Proces plazen\u00ed je tak\u00e9 velmi z\u00e1visl\u00fd na teplot\u011b v m\u00edst\u011b spoje. Prakticky bylo prok\u00e1z\u00e1no, \u017ee p\u0159i provozn\u00ed teplot\u011b ve spoji p\u0159esahuj\u00edc\u00ed 80\u00b0C dojde k rozta\u017een\u00ed spojov\u00e9ho kovu kv\u016fli p\u0159eh\u0159\u00e1t\u00ed, co\u017e zp\u016fsob\u00ed posunut\u00ed kontaktu na povrchu, vznik mal\u00e9ho mezeru a oxidaci. Kdy\u017e se provozn\u00ed proud sn\u00ed\u017e\u00ed a teplota se vr\u00e1t\u00ed do p\u016fvodn\u00edho kontaktu, kv\u016fli pokryt\u00ed oxidov\u00e9 vrstvy na kontaktu nen\u00ed mo\u017en\u00e9, aby se kovy p\u0159i p\u016fvodn\u00ed instalaci p\u0159\u00edmo dot\u00fdkaly. Zv\u00fd\u0161en\u00ed kontaktn\u00edho odporu p\u0159i ka\u017ed\u00e9 cyklick\u00e9 zm\u011bn\u011b teploty zvy\u0161uje teplo v dal\u0161\u00edm cyklu, a zv\u00fd\u0161en\u00e1 teplota d\u00e1le zhor\u0161uje provozn\u00ed stav spoje, \u010d\u00edm\u017e vznik\u00e1 za\u010darovan\u00fd kruh.<\/p>\n<p>(2) M\u011b\u0159en\u00e1 data typov\u00e9ho testu jsou obvykle provedena v laborato\u0159i a trvaj\u00ed kr\u00e1tkou dobu, obvykle ne d\u00e9le ne\u017e 8 hodin, nemaj\u00ed kumulativn\u00ed efekt zv\u00fd\u0161en\u00ed teploty a nelze je srovn\u00e1vat s dlouhodob\u00fdm provozem a nep\u0159etr\u017eit\u00fdm zah\u0159\u00edv\u00e1n\u00edm za\u0159\u00edzen\u00ed.<\/p>\n<p>(3) Nevhodn\u00fd tlak upev\u0148ovac\u00edch \u0161roub\u016f v m\u00edst\u011b spoje. N\u011bkte\u0159\u00ed mont\u00e1\u017en\u00edci \u010di \u00fadr\u017eb\u00e1\u0159i si mysl\u00ed, \u017ee \u010d\u00edm pevn\u011bji jsou spojovac\u00ed \u0161rouby uta\u017eeny v konektoru vodi\u010de, t\u00edm l\u00e9pe, ale ve skute\u010dnosti tomu tak nen\u00ed. Zejm\u00e9na u hlin\u00edkov\u00fdch sb\u011brn\u00fdch li\u0161t je pru\u017enostn\u00ed koeficient mal\u00fd; kdy\u017e tlak matice dos\u00e1hne ur\u010dit\u00e9 kritick\u00e9 hodnoty, pokud je pevnost materi\u00e1lu slab\u00e1, a pak se nad\u00e1le nevhodn\u011b zvy\u0161uje tlak, doch\u00e1z\u00ed k \u010d\u00e1ste\u010dn\u00e9 deformaci a vyv\u00fd\u0161en\u00ed kontaktu, ale p\u0159itom se sni\u017euje kontaktov\u00e1 plocha, zvy\u0161uje se kontaktn\u00ed odpor a naru\u0161uje se kontakt vodi\u010de. Vodivost vybran\u00fdch vodi\u010dov\u00fdch materi\u00e1l\u016f nespl\u0148uje po\u017eadavky, v\u011bt\u0161ina z nich pat\u0159\u00ed k nedostate\u010dn\u00e9 \u010distot\u011b surovin vodi\u010d\u016f.<\/p>\n<p>(4) Dal\u0161\u00ed faktory na m\u00edst\u011b, jako je nevhodn\u00fd postup mont\u00e1\u017ee a \u00fadr\u017eby \u2013 nap\u0159\u00edklad p\u0159i zpracov\u00e1n\u00ed, spojov\u00e1n\u00ed a instalaci sb\u011brn\u00e9 li\u0161ty nen\u00ed kontaktov\u00e1 plocha li\u0161ty spr\u00e1vn\u011b um\u00edst\u011bna, je nerovn\u00e1, nehladk\u00e1 a nen\u00ed pou\u017eita speci\u00e1ln\u00ed silikonov\u00e1 maziva atd., co\u017e vedlo k sn\u00ed\u017een\u00ed efektivn\u00ed kontaktov\u00e9 plochy a zv\u00fd\u0161en\u00ed kontaktn\u00edho odporu a zah\u0159\u00edv\u00e1n\u00ed.<\/p>\n<\/div>","protected":false},"excerpt":{"rendered":"<p>Po kr\u00e1tk\u00e9m sezn\u00e1men\u00ed s vysokonap\u011b\u0165ovou rozv\u00e1d\u011b\u010dovou technikou a poj\u010fme se pod\u00edvat na d\u016fvody zah\u0159\u00edv\u00e1n\u00ed vysokonap\u011b\u0165ov\u00e9 rozv\u00e1d\u011b\u010dov\u00e9 techniky p\u0159i jej\u00edm nap\u00e1jen\u00ed. Nev\u00edm, jestli v\u00e1s to bude zaj\u00edmat? Jsme odhodl\u00e1ni poskytovat v\u00e1m slu\u017eby nejvy\u0161\u0161\u00ed kvality, poj\u010fme se na to pod\u00edvat. (1) Vliv rozta\u017enosti [\u2026]<\/p>","protected":false},"author":2,"featured_media":1676,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_seopress_robots_primary_cat":"none","footnotes":""},"categories":[67],"tags":[],"class_list":["post-1672","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-industry-news"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.northpwr.cn\/cs\/wp-json\/wp\/v2\/posts\/1672","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.northpwr.cn\/cs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.northpwr.cn\/cs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.northpwr.cn\/cs\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.northpwr.cn\/cs\/wp-json\/wp\/v2\/comments?post=1672"}],"version-history":[{"count":1,"href":"https:\/\/www.northpwr.cn\/cs\/wp-json\/wp\/v2\/posts\/1672\/revisions"}],"predecessor-version":[{"id":1675,"href":"https:\/\/www.northpwr.cn\/cs\/wp-json\/wp\/v2\/posts\/1672\/revisions\/1675"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.northpwr.cn\/cs\/wp-json\/wp\/v2\/media\/1676"}],"wp:attachment":[{"href":"https:\/\/www.northpwr.cn\/cs\/wp-json\/wp\/v2\/media?parent=1672"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.northpwr.cn\/cs\/wp-json\/wp\/v2\/categories?post=1672"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.northpwr.cn\/cs\/wp-json\/wp\/v2\/tags?post=1672"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}