目錄TOC\o"1-5"\h\z低壓短路電流計(jì)算 21、 三相短路電流周期分量計(jì)算 22、 三相短路沖擊電流計(jì)算 23、 三相短路電流第一周期（0.02S）全短路電流有效值計(jì)算 34、 電動(dòng)機(jī)品閘管裝置對(duì)短路電流的影響 3配電變壓器出口側(cè)總斷路器的短路校驗(yàn) 141、 額定短路分?jǐn)嗄芰Γ↖cn）的校驗(yàn) 142、 額定短路接通能力（Icm）的校驗(yàn) 153、 額定短時(shí)耐受電流（Icw）的校驗(yàn) 16低壓短路電流計(jì)算1、三相短路電流周期分量計(jì)算三相短路電流周期分量按下式計(jì)算：'z' Rm^式中IZ’’? 三相短路電流周期分量有效值，KA；Up 低壓網(wǎng)絡(luò)平均額定線電壓，Up取400V；Z 每相總阻抗,m。；￡R 每相總電阻,m。；￡X￡ 每相總電抗,m。。低壓網(wǎng)絡(luò)一般以三相短路電流為最大，與中性點(diǎn)是否接地?zé)o關(guān)。2、三相短路沖擊電流計(jì)算電源供給的短路沖擊電流值，按下式計(jì)算：— — 001 0_01 —i=、：2*1-+⑵'，*eTa=、⑵"(1+eTa)=v'2*Kch*'" (1-2)chx Z Z Z Z式中ichx 三相短路沖擊電流，KA；<21" 三相短路電流周期分量的峰值，KA；Z顯*',，e一* 三相短路電流非周期分量，KA；Z0.01 三相短路電流沖擊系數(shù)；Kch=1+e-TaJ0J01e-Ta 三相短路電流非周期分量衰減系數(shù)；…X￡ 314R? 三相短路電流非周期分量衰減時(shí)間常數(shù)，S。如果電路內(nèi)只有電抗(R￡=0)，則Ta=8,Kch=2，即短路電流非周期分量不衰減。如果電路內(nèi)只有電阻(X￡=0)，則Ta=0，Kch=1，即非周期分量根本不發(fā)生。由此可見，Kch在1?2之間。3、 三相短路電流第一周期(0.02S)全短路電流有效值計(jì)算電源供給的全短路電流最大有效值：當(dāng)Kch>1.3時(shí)，按下式計(jì)算Ix=匕”*J1+2(K內(nèi)-1)2 (1-3)當(dāng)Kch^1.3時(shí)，按下式計(jì)算比較精確I入=Iz”*J1+50Ta (1-4)以上兩式Lhx 全短路電流的有效值，KA；Iz” 三相短路電流周期分量的有效值，KA；Kch 三相短路電流的沖擊系數(shù)；Ta 三相短路電流非周期分量衰減的時(shí)間常數(shù)，(S)。如果配電變壓器高壓側(cè)電源容量為無窮大，而在變壓器低壓側(cè)出口發(fā)生三相短路，這時(shí)短路回路阻抗，僅為變壓器自身的阻抗。SC(B)9、SC(B)10、S9、S10型變壓器的電阻Rb、電抗Xb值見后表1-1~表1-6。三相短路電流沖擊系數(shù)Kch見表1-7?表1-12。三相短路電流的周期分量Iz”、沖擊電流Ichx、全短路電流的有效值Ichx見表1-13?表1-18。4、 電動(dòng)機(jī)品閘管裝置對(duì)短路電流的影響一般只考慮距短路點(diǎn)近處的電動(dòng)機(jī)、品閘管裝置的影響，距短路點(diǎn)遠(yuǎn)處的電動(dòng)機(jī)、品閘管裝置可忽略不計(jì)。(1)電動(dòng)機(jī)對(duì)短路電流的影響

電動(dòng)機(jī)反饋的沖擊電流值，按下式計(jì)算:"6%人 (1-5)式中ichd 電動(dòng)機(jī)反饋的三相短路沖擊電流值，KA；Kchd 電動(dòng)機(jī)短路沖擊系數(shù)，一般為0.8?1.28，簡(jiǎn)化計(jì)算可取1；Ied 電動(dòng)機(jī)額定總電流，KA。電動(dòng)機(jī)反饋的全電流的有效值，按下式計(jì)算：彼E (1-6)式中Kchd、Ld 見上所述。(2)品閘管裝置對(duì)短路電流的影響品閘管裝置反饋的沖擊電流值，按下式計(jì)算:(1-(1-7)chG—Up式中ichG 品閘管裝置反饋的三相短路電流沖擊值，KA；Pe￡ 品閘管裝置供電的直流電動(dòng)機(jī)總功率，KW；Up 低壓網(wǎng)絡(luò)平均額定線電壓，V，一般為400V。(1-(1-8)chG chded式中膈、Ld見上所述。式中膈、Ld見上所述。1附表：變壓器的電阻Rb、電抗Xb表1-1：SC(B)9型變壓器10(11,10.5,6.3,6)±5%或±2x2.5%/0.4KVD,yn11,Y.yn0的阻抗序號(hào)型號(hào)變壓器容量Se(KVA)UkPkRX(%)(KW)(mQ)1SC9-315/1031543.15.0020.922SC9-400/1040043.63.6016.403SCB9-500/1050044.32.7513.094SCB9-630/1063045.42.1810.395SCB9-630/1063065.62.2615.406SCB9-800/1080066.61.6512.117SCB9-1000/10100067.61.229.688SCB9-1250/10125069.10.937.749SCB9-1600/1016006110.696.0410SCB9-2000/102000613.30.534.8311SCB9-2500/102500615.80.403.86注:根據(jù)順特電氣資料表1-2：SC(B)10型變壓器10(11，10.5,6.3,6)±5%或±2x2.5%/0.4KV D,yn11,Y.yn0的阻抗序號(hào)型號(hào)變壓器容量Se(KVA)UkPkRX(%)(KW)(mQ)1SC10-315/1031543.034.8920.902SC10-400/1040043.483.4816.373SCB10-500/1050044.262.7313.094SCB10-630/1063045.122.0610.375SCB10-630/1063065.202.1015.386SCB10-800/1080066.061.5212.107SCB10-1000/10100067.091.139.678SCB10-1250/10125068.460.877.739SCB10-1600/101600610.200.646.0310SCB10-2000/102000612.600.504.8311SCB10-2500/102500615.000.383.86注:根據(jù)順特電氣資料

序號(hào)型號(hào)變壓器容量SeUkPkRX（KVA）（%）（KW）(mQ)1S9-315/1031543.455.5621.072S9-400/1040044.204.2016.543S9-500/1050044.953.1713.194S9-630/1063055.802.3412.915S9-800/1080057.501.8810.176S9-1000/10100059.201.478.137S9-1250/101250511.001.136.508S9-1600/101600614.000.886.069S9-2000/102000618.000.724.8510S9-2500/102500622.500.583.88表1-3：S9型變壓器10(11,10.5,6.3,6)±5%/0.4KVD,yn11的阻抗注:根據(jù)福變電氣資料表1-4： S9型變壓器10(11,10.5,6.3,6)±5%/0.4KVY.yn0的阻抗序號(hào)型號(hào)變壓器容量SeUkPkRX（KVA）（%）（KW）（mQ）1S9-315/1031543.655.8921.152S9-400/1040044.304.3016.573S9-500/1050045.103.2613.214S9-630/106304.56.202.5011.705S9-800/108004.57.501.889.196S9-1000/1010004.510.301.657.397S9-1250/1012504.512.001.235.898S9-1600/1016004.514.300.894.599S9-2000/102000618.000.724.8510S9-2500/102500622.500.583.88注:根據(jù)福變電氣資料

S10型變壓器10(11,10.5,6.3,6)±5%或±2x2.5%/0.4KVD,yn11的阻抗序號(hào)型號(hào)變壓器容量Se(KVA)UkPkRX(%)(KW)(mQ)1S10-315/103154.54.306.9323.892S10-400/104004.55.105.1018.713S10-500/105004.56.083.8914.924S10-630/106304.57.232.9111.795S10-800/108004.58.842.219.276S10-1000/1010004.510.361.667.397S10-1250/1012504.512.331.265.908S10-1600/1016004.514.600.914.59S10型變壓器10(11,10.5,6.3,6)表1-6：±5%或±2x2?5%/0?4KVY?yn0的阻抗序號(hào)型號(hào)變壓器容量Se(KVA)UkPkRX(%)(KW)(mQ)1S10-315/103154.54.036.49823.7632S10-400/104004.54.924.92018.6603S10-500/105004.55.853.74414.8794S10-630/106304.56.892.77811.7615S10-800/108004.58.402.1009.2426S10-1000/1010004.59.301.4887.3527S10-1250/1012504.511.101.1375.8718S10-1600/1016004.514.000.8754.584

2附表：三相短路電流沖擊系數(shù)Kch表1-7：SC(B)9型變壓器10(11，10.5,6.3，6)±5%或土2x2.5%/0.4KVD,yn11,Yyn0的沖擊系數(shù)序號(hào)型號(hào)變壓器容量Se(KVA)UkTKchJ1+2(Kch-1)2(%)(S)J1+50*T1SC9-315/1031540.0131.471.202SC9-400/1040040.0151.501.233SCB9-500/1050040.0151.521.244SCB9-630/1063040.0151.521.245SCB9-630/1063060.0221.631.346SCB9-800/1080060.0231.651.367SCB9-1000/10100060.0251.671.388SCB9-1250/10125060.0261.691.399SCB9-1600/10160060.0281.701.4110SCB9-2000/10200060.0291.711.4111SCB9-2500/10250060.0301.721.43注:根據(jù)順特電氣資料表1-8：SC(B)10型變壓器10(11,10.5,6.3,6)±5%或±2x2.5%/0.4KV D,yn11，Y.yn0的沖擊系數(shù)序號(hào)型號(hào)變壓器容量Se(KVA)UkTKchJ1+2(Kch-1)2(%)(S)J1+50*T1SC10-315/1031540.0141.481.212SC10-400/1040040.0151.511.243SCB10-500/1050040.0151.521.244SCB10-630/1063040.0161.541.255SCB10-630/1063060.0231.651.366SCB10-800/1080060.0251.671.387SCB10-1000/10100060.0271.691.408SCB10-1250/10125060.0281.701.419SCB10-1600/10160060.0301.721.4210SCB10-2000/10200060.0301.721.4311SCB10-2500/10250060.0321.731.44注:根據(jù)順德電氣資料

序號(hào)型號(hào)變壓器容量SeUkTKchJ1+2(Kch-1)2（KVA）（%）（S）J1+50*71S9-315/1031540.0121.441.1752S9-400/1040040.0131.451.1863S9-500/1050040.0131.471.2014S9-630/1063050.0181.571.2815S9-800/1080050.0171.561.2766S9-1000/10100050.0181.571.2817S9-1250/10125050.0181.581.2948S9-1600/10160060.0221.641.3459S9-2000/10200060.0211.631.33710S9-2500/10250060.0211.631.337表1-9：S9型變壓器10(11,10.5,6.3,6)±5%/0.4KVD,yn11的沖擊系數(shù)注:根據(jù)福變電氣資料表1-10： S9型變壓器10(11，10.5,6.3,6)±5%/0.4KVD,yn11的沖擊系數(shù)序號(hào)型號(hào)變壓器容量SeUkTKchJ1+2(Kch-1)2（KVA）（%）（S）J1+50*71S9-315/1031540.0111.421.1612S9-400/1040040.0121.441.1803S9-500/1050040.0131.461.1934S9-630/106304.50.0151.511.2345S9-800/108004.50.0161.531.2476S9-1000/1010004.50.0141.501.2227S9-1250/1012504.50.0151.521.2418S9-1600/1016004.50.0161.541.2609S9-2000/10200060.0211.631.33710S9-2500/10250060.0211.631.337注:根據(jù)福變電氣資料

序號(hào)型號(hào)變壓器容量Se(KVA)UkTKchJ1+2(Kch-1)2(%)(S)J1+50*71S10-315/103154.50.0111.401.152S10-400/104004.50.0121.421.173S10-500/105004.50.0121.441.184S10-630/106304.50.0131.461.195S10-800/108004.50.0131.471.206S10-1000/1010004.50.0141.491.227S10-1250/1012504.50.0151.511.238S10-1600/1016004.50.0161.541.25表1-11:S10型變壓器10(11,10.5,6.3,6)±5%或±2x2.5%/0.4KVD,yn11的沖擊系數(shù)表1-12：S10型變壓器10(11,10.5,6.3,6)±5%或±2x2.5%/0.4KVY.yn0的沖擊系數(shù)序號(hào)型號(hào)變壓器容量Se(KVA)UkTKchJ1+2(Kch-1)2(%)(S)J1+50*71S10-315/103154.50.0121.421.172S10-400/104004.50.0121.441.183S10-500/105004.50.0131.451.194S10-630/106304.50.0131.481.215S10-800/108004.50.0141.491.226S10-1000/1010004.50.0161.531.257S10-1250/1012504.50.0161.541.268S10-1600/1016004.50.0171.551.27

3附：三相短路電流的周期分量IZ’、’沖擊電流Ichx、全短路電流的有效值Ichx表1-13：SC(B)9型變壓器10(11，10.5,6.3，6)±5%或±2x2.5%/0.4KVD,yn11,Y.yn0的短路電流序號(hào)型號(hào)變壓器容量Se(KVA)UkI''i,IchIe(%)Ch(KA)(A)1SC9-315/10315410.7422.3512.91454.662SC9-400/10400413.7529.2116.87577.353SCB9-500/10500417.2637.0321.38721.694SCB9-630/10630421.7646.7026.97909.335SCB9-630/10630614.8334.2219.88909.336SCB9-800/10800618.8944.1325.701154.707SCB9-1000/101000623.6856.0632.711443.388SCB9-1250/101250629.6470.6341.271804.229SCB9-1600/101600637.9991.3253.442309.4010SCB9-2000/102000647.53114.7867.242886.7511SCB9-2500/102500659.48144.6784.883608.44注:根據(jù)順特電氣資料表1-14：SC(B)10型變壓器10(11,10.5,6.3,6)±5%或±2x2?5%/0.4KVD,yn11,Yyn0的短路電流序號(hào)型號(hào)變壓器容量Se(KVA)UkI''i,IchIe(%)ch(KA)(A)1SC10-315/10315410.7622.5213.01454.662SC10-400/10400413.8029.5217.04577.353SCB10-500/10500417.2837.1321.44721.694SCB10-630/10630421.8547.4427.40909.335SCB10-630/10630614.8834.7520.23909.336SCB10-800/10800618.9544.8726.191154.707SCB10-1000/101000623.7356.7733.191443.388SCB10-1250/101250629.6971.5341.881804.229SCB10-1600/101600638.0692.4654.232309.4010SCB10-2000/102000647.59115.7967.942886.7511SCB10-2500/102500659.55145.8385.693608.44注:根據(jù)順特電氣資料

表1-15：S9型變壓器10(11,10.5,6.3,6) ±5%/0.4KVD,yn11的短路電流序號(hào)型號(hào)變壓器容量SeUkI''i,IchIe（KVA）（%）Ch(KA)（A）1S9-315/10315410.6021.5312.46454.662S9-400/10400413.5327.7616.05577.353S9-500/10500417.0335.4120.45721.694S9-630/10630517.6038.9922.55909.335S9-800/10800522.3249.2728.491154.706S9-1000/101000527.9461.8935.801443.387S9-1250/101250535.0278.2545.301804.228S9-1600/101600637.7087.2050.692309.409S9-2000/102000647.07108.3462.932886.7510S9-2500/102500658.83135.4278.663608.44注:根據(jù)福變電氣資料表1-16：S9型變壓器10(11，10.5,6.3,6)±5%/0.4KY,yn0的短路電流序號(hào)型號(hào)變壓器容量SeUkI''i.IchIe（KVA）（%）Ch(KA)（A）1S9-315/10315410.5221.0812.21454.662S9-400/10400413.4927.5315.92577.353S9-500/10500416.9735.0520.25721.694S9-630/106304.519.3141.2623.82909.335S9-800/108004.524.6153.1630.701154.706S9-1000/1010004.530.5264.5737.281443.387S9-1250/1012504.538.3882.4847.631804.228S9-1600/1016004.549.41107.7862.272309.409S9-2000/102000647.07108.3462.932886.7510S9-2500/102500658.83135.4278.663608.44注:根據(jù)福變電氣資料

表117 S10型變壓器10(11,10.5,6.3,6) ±5%或±2x2.5%/0.4KVD,yn11衣 的短路電流序號(hào)型號(hào)變壓器容量Se（KVA）UkI''i.IchIe（%）Ch(KA)（A）1S10-315/103154.59.2918.4110.68454.662S10-400/104004.511.9124.0013.89577.353S10-500/105004.514.9830.5317.65721.694S10-630/106304.519.0139.2622.68909.335S10-800/108004.524.2450.4929.161154.706S10-1000/1010004.530.5064.4637.211443.387S10-1250/1012504.538.3081.8147.231804.228S10-1600/1016004.549.33107.1461.892309.40序號(hào)型號(hào)變壓器容量Se（KVA）UkI''i,IchIe（%）Ch(KA)（A）1S10-315/103154.59.3718.8710.93454.662S10-400/104004.511.9724.3214.07577.353S10-500/105004.515.0530.9517.89721.694S10-630/106304.519.1139.9023.04909.335S10-800/108004.524.3751.3429.651154.706S10-1000/1010004.530.7966.6038.471443.387S10-1250/1012504.538.6284.3548.741804.228S10-1600/1016004.549.48108.4162.652309.40表1-18：S10型變壓器10(11,10.5,6.3,6)±5%或±2x2.5%/0.4KVY.yn0的短路電流二、配電變壓器出口側(cè)總斷路器的短路校驗(yàn)根據(jù)國(guó)家標(biāo)準(zhǔn)《低壓配電設(shè)計(jì)規(guī)范》（BG50054-95）第2.1.1條第五款“電器應(yīng)滿足短路條件下的動(dòng)穩(wěn)定與熱穩(wěn)定的要求。用于斷開短路電流的電器，應(yīng)滿足短路條件下的通斷能力”，和第2.1.2條“驗(yàn)算電器在短路條件下的通斷能力，應(yīng)采用安裝處預(yù)期短路電流周期分量的有效值，當(dāng)短路點(diǎn)附近所接電動(dòng)機(jī)額定電流之和超過短路電流的1%時(shí)，應(yīng)計(jì)入電動(dòng)機(jī)反饋電流的影響”的規(guī)定，在選擇低壓變壓器出口側(cè)總斷路器時(shí)，應(yīng)根據(jù)國(guó)家標(biāo)準(zhǔn)《低壓開關(guān)設(shè)備和控制設(shè)備低壓斷路器》（GB14048.2-94）的有關(guān)規(guī)定，對(duì)低壓斷路器的額定短路分?jǐn)嗄芰Α㈩~定短路接通能力和額定短路時(shí)耐受電流進(jìn)行校驗(yàn)。1、額定短路分?jǐn)嗄芰Γ↖cn）的校驗(yàn)斷路器的額定短路分?jǐn)嗄芰Γ↖cn）分為額定極限短路分?jǐn)嗄芰Γ?國(guó)）和額定運(yùn)行短路分?jǐn)嗄芰Γ↖cs）。（1） 額定極限短路分?jǐn)嗄芰Γ↖cu）額定極限短路分?jǐn)嗄芰Γ↖cu）是斷路器在規(guī)定的試驗(yàn)條件下極限短路分?jǐn)嚯娏髦怠０匆?guī)定的試驗(yàn)程序（O-t-C0）動(dòng)作之后，不考慮繼續(xù)承載它的額定電流。（2） 額定運(yùn)行短路分?jǐn)嗄芰Γ↖cs）額定運(yùn)行短路分?jǐn)嗄芰Γ↖cs）是指斷路器在規(guī)定試驗(yàn)條件下的一種比額定極限短路分?jǐn)嚯娏餍〉姆謹(jǐn)嚯娏髦?，Ics是Icu的一個(gè)百分?jǐn)?shù)（見表2-1）。按規(guī)定的試驗(yàn)程序（O-t-CO-t-CO）動(dòng)作后，考慮繼續(xù)承載它的額定電流。在上述兩種短路分?jǐn)嗄芰Γ↖cu、Ics）試驗(yàn)程序中，O------表示分?jǐn)嗖僮鳎籆O----表示接通操作后，緊接分?jǐn)嗖僮鳎籺 表示兩個(gè)相繼操作之間的時(shí)間間隔，一般為3min，如果脫扣器還來不及再扣，則可延長(zhǎng)全能再扣為止。由上述可以看出，額定極限短路分?jǐn)嗄芰Γ↖cu），指的是斷路器在分?jǐn)嗔嗽摱搪冯娏骱螅€可以再正常運(yùn)行并分?jǐn)噙@一短路電流一次，至于以后是否

正常接通及分?jǐn)?，斷路器不予保證。而額定運(yùn)行短路分?jǐn)嗄芰Γ↖cs）正常接通及分?jǐn)啵瑪嗦菲鞑挥璞ＷC。而額定運(yùn)行短路分?jǐn)嗄芰Γ↖cs）則指的是斷路器在該短路電流下可多次正常分?jǐn)?。在?shí)際工程中，不希望在斷路器發(fā)生一次事故跳閘后，立即更換斷路使用類別ABIcs/Icu%Ics/Icu%25—50507575100100表2-1Ics和Icu標(biāo)準(zhǔn)比例器，所以如果按照額定極限短路分?jǐn)嗄芰Γ↖cu）來校驗(yàn)斷路器的分?jǐn)嗄芰?，必然?huì)給用戶帶來不安全的隱患。因國(guó)家標(biāo)準(zhǔn)《低壓配電設(shè)計(jì)規(guī)范》（GB50054-95）沒有明確用那種分?jǐn)嗄芰Γ↖cu或Ics）來校驗(yàn)，所以設(shè)計(jì)并不統(tǒng)一。筆者認(rèn)為：工程設(shè)計(jì)時(shí)，用額定運(yùn)行分?jǐn)嗄芰Γ↖cs）校驗(yàn)斷路器是穩(wěn)妥可靠的。根據(jù)《低壓配電設(shè)計(jì)規(guī)范》（GB50054-95），校驗(yàn)斷路器在短路條件下的分?jǐn)嗄芰r(shí)，應(yīng)采用安裝處預(yù)期短路電流周期分量的有效值。當(dāng)斷路器的分?jǐn)鄷r(shí)間小于0.02秒IZI （2一1