Tsunonin Amurka na Standards: Dukkan da aka Yi wa IEE-Business da Chinese Switchgear Standards

Daga da IEEE Std C37.20.9™ yana bayyana abubuwan da za su dacewa, kuma masu shirya da kuma tattalin gida na gas-gabas (MEGIS) wadanda suna amfani da gas da kisan kasa mai yawa a cikin hanyoyi a kan kasa da kasa zuwa 52 kV. Wannan ya haɗa da, amma ba tare da, fadin daɗi, koguna, bushings, busbars, instrument transformers, cable terminations, meters, da kuma control/protection relays. A nan daɗinsu, wasu ko duk fitaccen mafi girman hanyar da suke da gas da kisan kasa. Daga daɗin yana ci gaba da tattalin gida da ke kan da take da kai.

A tarihin, babban nau'in daɗin da aka yi a tattalin arziki na Amurka shine daɗin da ke kan da hanyoyi. Don hanyoyin daɗin da ke kan da tsawon kasa, ana iya amfani da American-style pad-mounted transformers, inda mutanen hanyoyin da suke da kasa da koguna da kasa da kusa da transformer core da windings a cikin tank da ke kan da oil da kisan kasa, ko kuma daɗin da ke kan da hanyoyi. Saboda haka, an samun daɗin da ke kan da gas a Amurka ne da rike.

Bayan an samu daɗin da ke kan da gas a tattalin arziki na Amurka daga European manufacturers kamar ABB da Schneider Electric, masu sallama sun hana amincewa da kuma samun wannan fasahar. Saboda haka, standard na IEEE don daɗin da ke kan da gas an yi shi a lokacin da ta fiye da kuma an ruwaito a shekarar 2019. Wannan standard yana da nasara da IEC standards, amma an yi tasiri ga parametere, kudin, da kuma abubuwan da za su shirya don zama da standard na IEEE C37.20.2 da sauran standards na IEEE, musamman don tabbatar da abubuwan da za su shirya don safety requirements na IEEE.

1. Farkon Inganci don Samun

a) Tsayin lafiya: maximum +40 °C; masu kyau a ranar 24 da ba biyo +35 °C; minimum –5 °C.
b) Kasa: ba biyo 3,300 feet (1,000 meters).
c) Rating na protection enclosure: NEMA 250 Type 1 (IP20) don tattalin gida; Type 3R (IP24) don tattalin gida.

Idan kana nemi GB/T 11022, daɗin da ke kan da tattalin gida na China suna kula da uku farkon inganci: –5 °C, –15 °C, da –25 °C. Tsayin lafiyar da ke minima a IEEE C37.20.9 don daɗin da ke kan da gas (–5 °C) yana da maƙa daidai da tsayin lafiyar da ke minima a IEEE C37.20.2 don daɗin da ke kan da hanyoyi (–30 °C). Saboda haka, daɗin da ke kan da gas da ke dace da standards na China zai iya tabbata da abubuwan da za su shirya a IEEE C37.20.9.

Tafel 1 a nan yana nuna abubuwan da za su shirya a IEEE C37.20.9 don rated voltage, power-frequency withstand voltage, da lightning impulse withstand voltage don daɗin da ke kan da gas.

Tafel 1 – Insulation Voltage Ratings for Gas-Insulated Switchgear per IEEE C37.20.9

Duk da na iya a kan standard American kuma China suna bambanta. Saboda haka, gas-insulated switchgear (GIS) ya kamata a tabbatar da abubuwa na power-frequency withstand voltage da rated lightning impulse withstand voltage wadda ake bayyana a cikin standard IEEE. Misali, GIS cabinet na 12 kV wanda ake tsara ta a kan standard Chinese zai iya tabbatar da abubuwan da ake magana game da 4.76 kV class a kan standard Amurka, amma GIS cabinet na 24 kV daga China zai iya tabbatar da abubuwan da ake magana game da 27 kV.

IEEE Std 386™-2016 tattauna abubuwan da suka fi yawa don separable insulated connectors wadanda ake amfani da su a cikin distribution systems na 2.5 kV zuwa 35 kV—wanda ake kira "American-style elbow connector" standard. Wannan connectors suna amfani da su sosai a kan equipment na U.S. standard kamar pad-mounted transformers da cable distribution boxes. Bambanta, Chinese gas-insulated switchgear tana amfani da cable bushings da plugs wadanda suka tabbatar da EN 50181. Standard IEEE na gas-insulated switchgear tana bayyana abubuwan da suka fi yawa don dielectric test don various types of cable termination accessories.

2 Rated Current
Abubuwan da suka fi yawa don rated continuous current na main busbars a kan IEEE gas-insulated switchgear (MEGIS) sun haɗa shi 200 A, 600 A, 1200 A, 2000 A, 2500 A, 3000 A, da 4000 A—wadanda sun bambanta da ratings na Chinese common kamar 630 A, 1250 A, da 3150 A.

3 Rated Frequency
Standard IEEE tattaune rated frequency na 60 Hz, amma standard frequency na China shine 50 Hz. Yawan 60 Hz shine mafi yawan ƙarfin jirgin ruwa da short-circuit breaking performance. Daga baya ta GB/T 11022, don switchgear da controlgear na 50 Hz ko 60 Hz—idana ba a kasance ferromagnetic components a nan current-carrying parts—idana a samu temperature rise a 50 Hz ya kai 95% na maximum allowable limit, wannan equipment za a ce ta tabbatar da abubuwan na biyu frequencies, idana 60 Hz temperature rise requirement.

Amma, saboda babban heat dissipation a kan gas-insulated switchgear da thermal margin na musamman, design improvements ana bukata don tabbatar da 60 Hz requirements. Products wadanda suka tattara 1.1× rated current temperature rise test a kan standard Chinese zai iya tabbatar da 60 Hz requirement.

4 Rated Short-Time Withstand Current and Rated Peak Withstand Current
Abubuwan da suka fi yawa don short-time withstand current na IEEE gas-insulated switchgear suna nuna a Table 3. Bambanta da Chinese standards, wanda suka bayyana short-circuit duration na 3 s ko 4 s, standard IEEE tattaune short-circuit duration na 2 seconds.

Karin, saboda system IEEE tana yi ita a 60 Hz (bambanta da 50 Hz), rated peak withstand current tattaune 2.6 times na rated short-time withstand current. Misali, rated short-time withstand current na 31.5 kA tana nufin rated peak withstand current na 82 kA—miliyan 80 kA wanda ake amfani da shi a China. Don tabbatar da electrodynamic forces wadanda ake gina game da peak short-circuit currents, contact pressure da mechanical strength na components kamar contacts tana buƙata.

Table 2 – Recommended Short-Time Withstand Current Ratings for IEEE Gas-Insulated Switchgear