Liema hummet jisbgħu biex jiżġġmu r-prezz tal-falj tal-kurrent transformers barra?

1. Ricerka u l-Iżloq u l-Kontest
1.1 L-Importanza tal-Current Transformers

Il-current transformers jilgħu ruħhom fl-ivvjaġġar tas-silġ u l-isolazzjoni elettrika. Huma jkonvertixxu s-silġ kbir tas-sistema primarja f'silġ tan-nifs proporzjonali żgħir, li jkun furnit għal instrumenti ta’ misuratura, protezzjoni reġolaturi, u dispositivi awtomatiku. Fis-sistema tal-enerġija, ir-ruħa tal-current transformers hija mhux sustituwelabbli u tħallif direttament ruħa wkida fil-funzjonament sigur u stabil tat-teljana tal-enerġija.

1.2 L-Ambjent Tax-Xogħol Tuffieħ tal-Current Transformers all-Ħalijiet

Il-current transformers all-ħalijiet soliti jisbibu ambjenti elettriki u naturali anormali, skont hawn huwa rata ta’ falliment tagħhom ikun tgħid dawn. Minħabba l-kondizzjonijiet prattika, il-kontrollabilità tal-ambjenti elettriki u naturali hija limitata. Għalhekk, huwa aktar neċessarju biex is-sigurtà tal-kożinazzjoni tagħhom fis-sistema primarja tkun assikurata sabiex tista’ tgħaqqad akk barra mill-ambjent.

1.3 It-Teknoloġija Tradizzjonali Mhux Perfetta tal-Current Transformers all-Ħalijiet

Għal l-kożinazzjoni bejn it-top tal-pila tal-current transformers all-ħalijiet u l-barri tal-ram, is-silġ ta’ kontatt mhux aħjar. Waqt l-operazzjoni all-ħalijiet tal-lanġas, kif niesha l-kożinazzjoni hi b’tajb u fiduża, taffettewa direttament il-kapaċità tas-silġ. Silġ ta’ kontatt żgħir, kontatt mhuwiex aħjar, u reżistanza ta’ kontatt eċċessiva jistgħu jiġu sorgenti ta’ ħalqa. Jekk ma jiġux skoperti u ma jiġux affrontati ftit, jkun jistgħu jidħaqhom it-top tal-pila u l-barr tal-ram magħqud. L-ħalqa eċċessiva u l-ħal ta’ ħalqa waħda ħafna jistgħu jidħaqhom anki l-current transformer all-ħalijiet.

2. Il-Status tal-Falliment tal-Current Transformers fil-Substations ta’ Awtorità Partikulari tal-Providenza tal-Enerġija

Jkollhom kumpluttament ħames substation all-ħalijiet taht l-awtorità ta’ awtorità partikulari tal-providenza tal-enerġija. Minnu, fil-10kV outgoing lines u l-oqsma ta’ xitan tal-transformator prinċipali tal-35kV Substation 1 u Substation 2, hemm 33 current transformers post-type dry-type tal-model LBZW - 10. Il-pile heads huma tipu screw, u l-barri tal-alumini (tal-ram) huma imfissrati fuq is-screw permezz ta’ dwejjet ta’ fuq u tal-lejl. Ikkeltru minn ħalqa fil-pile heads u l-barri tal-alumini (tal-ram) magħquda, u anki midħul ta’ barra tal-alumini u tixrid tal-current transformers qagħad iffrutaw ftit darbiet.

Permezz ta’ analisi statistika tal-falliment u difetti tal-equipment prinċipali tal-Substation 1 fis-sena 2008, 2009, u 2010: Minn ftit tipi ta’ equipment prinċipali, kif huma current transformers, transformatori prinċipali, disjunctors, u voltage transformers, il-proporzjoni tal-falliment tal-current transformers hija 28%, li tkun l-ebda. Dan juri li, taħt l-istess kondizzjonijiet operattivi, il-current transformers huma aktar inclinati għal falliment kemm in-nisa. L-analisi approfondita turi li l-numru tal-falliment fis-sal-u trid huwa relazjonat diretta mal-ħin. Id-dettalji speċifiċi huma mostrati ftit fit-tabella sew.

Minn fit-tabella, tista’ tara intuitivament li l-falliment huma konċentrati fis-silġ tal-inundazzjoni minn Mejju sa Awwissu (speċjalment f’Ġunju). Il-mitla mensili tal-falliment fis-sal-u trid tigi 1.17 darba, li turi li l-akbar kapaċità tas-silġ, aktar inclinati huma l-current transformers għal falliment.

L-analisi approfondita tal-numru ta’ falliment turi li l-fatturi prinċipali tal-falliment huma: minn 2008 sa 2010, 14 falliment kienu causati minn falliment fil-joints tal-current transformers, u 2 falliment kienu causati minn fulmini u fatturi oħra. Iktar minn iz-zewġ kazijiet ta’ dan id-daħan direttament minn fulmini fis-2008 u 2009, il-puntijiet oħra tal-falliment huma fil-kożinazzjonijiet bejn il-pile heads u l-barri tal-alumini (tal-ram).

Il-modi prinċipali tal-għażla tal-falliment huma: ripetuzzjoni ta’ screws u tiswil ta’ dwejjet tal-lejl u washers imxarra; tiswil ta’ barra tal-alumini imxarra; tiswil tal-current transformer (meta l-pile head tkun imxarra u l-test tal-insulation jiġi fail). Sibas, dawn il-modi ma jistgħux elimina funzjonalment dawn il-falliment.

3. Analisi tal-Kausi tal-Falliment tal-Current Transformers u Misures Kontra

Permezz ta’ analisi, huwa meħtieġ li jkun hemm erba’ kausi prinċipali tal-falliment fil-10kV current transformers all-ħalijiet:

3.1 Kausi tal-Equipment

Is-struttura stessa tal-current transformer mhux ragionevoli.

3.2 Kausi Umani

Il-livell tekniku tal-personnel tal-manteniment mhux aħjar, u l-manteniment ta’ kull jorn mhux aħjar.

3.3 Problemi ta’ Mod

Is-soluzzjonijiet tal-falliment permezz ta’ esperjenza, bl-inkluzjoni ta’ modi diretti.

3.4 Fatturi tal-Link

Il-current transformers joperjaw taħt kapaċità tas-silġ eċċessiva għal tid ħafna, u l-substation hija situata f’dinja tal-ġebel umida, skont hawn l-joints huma inclinati għal korozzjoni u ossidazzjoni.

Huwa kkonfermat li l-kaus primarju huwa l-istruttura mhux ragionevoli tal-current transformer stess. Is-silġ ta’ kontatt bejn il-pile head tipu screw u l-barr tal-ram huwa troppo żgħir, li huwa l-kaus prinċipali tal-idħal ta’ barra tal-alumini u t-idħal tal-heat tal-current transformer. L-improvement tal-kożinazzjoni bejn il-pile head tal-current transformer all-ħalijiet u l-barr tal-ram, l-aument ta’ is-silġ ta’ kontatt, u r-reddizzjoni ta’ reżistanza ta’ kontatt saru l-directions ta’ improvement. Ftiek, huwa prevedut li jiddesigned wire clamp biex jagħmel dan.

4. Implementazzjoni Speċifiċa
4.1 Determina l-Specificazzjoni tal-Wire Clamp

Skont l-outer diameter (12mm, coarse thread) tal-pile head tal-10kV current transformer all-ħalijiet tal-Substation 1, customizza double-hole pole-clamping wire clamp mill-manufacturers, bil-model M - 12.

4.2 Installazzjoni u Verifikazzjoni ta’ Prova

Install the improved wire clamp that meets the GB - 2314 - 2008 standard in the department's test area on the test current transformer. It is found that it can be in close contact with the pile head and expand the contact area.

4.3 Full-Substation Test Application

Screw the double-hole copper pole-clamping wire clamp into the screw of the current transformer, and tighten the fixing screw to ensure the contact area and connection firmness, and reduce the contact resistance. Conduct a full-substation test on Substation 1 to improve the connection condition between the pile head of the outdoor current transformer and the copper bar.

5. Effect Inspection

After half a year of actual operation and observation and analysis of installing the double-hole pole-clamping wire clamp on the pile heads of 10kV outdoor current transformers in the entire Substation 1, the following conclusions are drawn:

5.1 Contact Area Improvement

Before improvement, the contact area between the pile head and the copper bar was 2.26cm². After improvement, it is 15cm², and the expansion ratio reaches 563.7%.

5.2 Contact Resistance Reduction

Measured with a loop resistance measuring instrument, the contact resistance when the pile head directly fixes the aluminum bar before improvement is 608μΩ. After improvement (fixed with a double-hole copper pole-clamping wire clamp), it is 460μΩ, and the reduction ratio reaches 24.3%.

5.3 Temperature Reduction

Under the same load (150A), the infrared imaging temperature measurement value before improvement is 52℃, and after improvement, it is 46℃, and the temperature reduction rate is 11.5%.

5.4 Failure Rate Reduction

Track and investigate the improved current transformers. The failure statistics during the flood season (May to August) show that: the total number of failures before improvement is 14 times (an average of 3.67 times per month), and the total number of failures after improvement is 1 time (caused by a lightning strike in June). The number of failures during the flood season has decreased from nearly 1.17 times per month to 0.25 times per month.

After the transformation, except for the failure caused by a lightning strike, no failures such as heat generation and burning out have occurred. The proportion of the number of failures of current transformers among the main primary equipment has decreased to less than 15%. Installing the improved double-hole copper pole-clamping wire clamp on the pile heads of 10kV outdoor current transformers in the entire Substation 1 increases the contact area, reduces the contact resistance, and successfully reduces the failure rate of outdoor current transformers.

Calculated based on a 10kV line being out of power for 12 hours, a current of 200A, and an electricity price of 0.5 yuan, each reduction of one power outage can increase the electricity fee by about more than 20,000 yuan. Ten times can reach more than 200,000 yuan, which not only improves the power supply reliability but also brings huge economic benefits to the enterprise.