能量公式

第一章：发电厂主接线图及经济比较第一节：发电厂主接线图1、一号发电厂，容量50MW分两台发电机组。主要参数如下：QF2-25-2,容量25MW，cos=0.9，Ve=10.5,Xd13.6%Xd225.6%。厂用电率为6%2、出线为安回数的确定。厂支配员荷：（10KV电压级）1）最大运行方式下：Pgim37.91MW则支配负荷PZMP片用FG1M50506%37.91%9.09MWSZMPZM/COSN9.09/0.910.1MVA每回输送2MVA，则需要送电的回路数为10.1/26回，220KV级总出线为7回2）最小运行方式下：Pgm19.9MW则支配负荷：PzmPP厂用PGm50506%19.0927.91MWSZMPZM/COS27.91/0.931MVA每回输送2MVA，则需要送电的回路书为31/2=16回220KV的总出线为17回3）可行性接线图见发电厂主接线4）两个方案的比较内\项10.5KV侧接线220KV侧接线经济性（隔离开关和断路器个数）特点结论方案双母不分段接线双母线不分段断路器12个隔离开关20个供电可靠运行方便灵活扩建方便可完成如并列与解列的特殊功能结论：通过以上的比较方案二较优于方案一,所以选择方案•-■方案单母分段双母线不分段断路器12个隔离开关供电可靠运行方便特殊情况可不间断12个供电第二章短路电流的计算第一节发电厂主变压器的选择.正常时S,S22Pg(16%)PZM/2COS225(16%)9.09/20.921.061MVA.故障时：SiS2[2Pg(16%)Pzm]70%/COS1.10=[225(16%)9.09]70%/0.91.10=26.8MVA选择SFP731500/22型变压器2.厂用变压器容量选择(厂备用变压器)SNFG6%/cosg256%/0.91667KVA故选择S7-2000/10型变压器第二节短路电流的计算：发电厂短路图及短路点如图10.5KV2发电厂的参数计算（取Sb100MVA,VbVav）1）发电机等值电抗标之值0.49Xd*Xd2*XG*XdSb/Sn0.136100/25/COSg0.136100/25/0.92）主变压器参数：XT1*XT2*Uk5/100Sb/Sn14100/10031.50.492）厂用变及厂备用变参数：XT0*XT2*XT4*5.5100SbSn5.510010022.75短路计算1）.转移电抗a.d-3点短路时,等值电路如图示：图2-2-3XstXsXT1/20.5110.444/20.733XstXsXT1/20.5110.444/20.7330舞=10舞=1据《发电厂电气参考资料》P75网络变换公式5'忽略等值电路中无用的支路则丫1/Xst1/Xd21/Xdi1/Xt3=1.346+2.041+2.041+0.364=5.81xKSXSTXTSY0.7332.755.8111.712xK2Xd2XT3Y0.492.75508170829xK1Xd1XT3Y0.492.755.817.829d-2短路时图2-2-6XksXsXT10.5110.44420.733XksXsXT10.5110.44420.733XjSbd-2短路时，如图2-2-5,2-2-6XjSbd-2短路时，如图2-2-5,2-2-6XkiXk2Xdi0.49XK2XK1xskl乌iQ^r-lOi=1X.0哥=1图2-2-8XdiXT10.490.4440.934Xd2XT20.490.4440.934Xs0.5112、计算电抗ad-3短路时，如图2-2-2，图2-2-3，图2-2-4XksSn11.712759.76SB1000.9Xj1Xj2Xk2色7.82925—SB1000.92.175s^0.733s^0.7335(0)Ij2(0)0.4715(0)Ij2(0)0.471XjsXksSB75100丽0.611Xj1Xj2XkiSnSb0.49250.1231000.9cd-1短路时，如图Xj2XS1XkiSnSb0.934251000.90.259XjSXkSSNSb0.511751000.90.4264.短路电流据《电力系统分析》上册附表5ad-1短路TOC\o"1-5"\h\z5(0)Ij2(0)4.178Ij1(0.2)Ij2(0.2)3.106Ij1()Ij2()Ij2(4)2.404Ijs(0)2.501Ijs(0.2)2.089Ijs()Ijs(4)2.143bd-2短路5(0)Ij2(0)8.963Ij1(0.2)Ij2(0.2)5.22Ij1()Ij2()Ij2(4)2.512Ijs(0)1.748Ijs(0.2)1.539Ijs()Ijs(4)1.884cd-3短路5(0.2)Ij2(0.2)0.448Ij1()Ij2()Ij2(4)0.476Xjs9.763.45Xjs9.763.45鼻(0)鼻(0.2)Ijs()119.760.1025•短路点电流有名值及短路电流冲击值220KV系统的额定电流Sn75IniIb』0.209Sb0.9230V3GiG2发电机n2Sn,3Ub250.9230.30.071)d-1短路时的有名值II1(0)I2(0)Ij(0)In2Ij2(0)In24.1780.0070.292Ii(0.2)12(0.2)Ij(0.2)In2Ij2(0.2)In23.1060.0070.217TOC\o"1-5"\h\zIi()I2()Ij()In2Ij2()In22.4040.0070.168Is(0)IjS(0)In12.5010.2090.523Is(0.2)IjS(0.2)In12.0890.2090.437Is()IjS()Im0.1430.2090.4482)短路电流的冲击值据《发电厂电气毕业设计参考资料》P95我国推荐的冲击系数所以d-1短路时，发电机G1G2ich1ich22.63I1(0)2.630.920.768Ich1Ich21.5611(0)1.560.920.456S1S23IchUn30.292230116.32其它短路时各值详见表第三章：各参数选择和校验第一节：各参数Igmax的计算据《发电厂电气毕业设计参考资料》P105发电机端口Igmax1.05—Q3Pn25变压器高压端口1gmax1.05变压器低压端口1gmax1.05母线分段断路器1gmax1.055母联断路器6厂用断路器710KVUnCOS3UnSn3UnSn3Un1.051.604KAJ310.50.91.051.051.05母线8220KV母线31.5322031.5310.531.532200.087KA1.819KA0.087KA第二节断路器和隔离开关的选择与校验母联出现断路器1）选择：根据《发电厂电气部分》P491表2-18选得设备名称设备型号额定开断电流（KA）极限通过电流（KA）热稳定电流（KA）分闸时间（s）断路器:ZND-10-16005012550(3s)0.065隔离开关:GN2-10-20008536(10s)2）校验：1.1断路器校验a开断电流INBr50(KA)IkI2"Is"8.01113.69521.706INBrb关合电流iNCL125(KA)ishish2ishs21.5536.8458.39inclc热稳定校验22Itt50237500II()21()s8.6343.83812.472222QkI2tdz12.47225.165803.4211t7500短路时间td5tkd50.0655.065(s)I"21.70612.4721.74查《发电厂电气部分课程设计参考资料》P112图5-1tz5.1td1s则tdztz5.1222Itdz12.47225.1793.31Itt1.2隔离开关校验a动稳定校验iNCL85（KA）ishish2ishs21.5536.8458.39inclb热稳定校验222Itt3621012960Itdz793.31（G2发电机机端断路器及隔离开关同上）母线分段断路器最大持续电流：Igmax1.604（KA）1）选择：根据《发电厂电气部分》P491表2-18选得设备名称设备型号额定开断电流（KA）极限通过电流（KA）热稳定电流（KA）分闸时间（s）断路器ZN12-10-16005012550(3s)0.065隔离开关GNE-10-20008536(10s)2)校验：1.1断路器校验a开断电流INBr50TOC\o"1-5"\h\z11IKI2"—Is"13.695—8.01117.7INBr22b关合电流iNCL12511ishish2ishs36.8421.5547.615iNCL22c热稳定校验22Itt5023750011II()2-I()s3.838—8.6348.155(KA)22Qk12tdz8.15525.665376.75ltl7500短路时间td5tkd50.0655.065(s)I"17.7I"17.72.17I8.155查《发电厂电气部分课程设计参考资料》P112图5-1tz5.6td1s则tdztz5.6222Itdz8.1555.6372.42Itt1.2隔离开关校验a动稳定校验iNCL85(KA)1•ishish2ishs47-615iNCL2b热稳定校验222Itt3621012960Itdz376.75变压器低压侧最大持续电流：—ax1.8191）选择：根据《发电厂电气部分》P491表2-18选得设备名称设备型号额定开断电流（KA）极限通过电流（KA）热稳定电流（KA）分闸时间（s）断路器ZM2-10-20005012550(3s)0.065隔离开关:GN2-10-200085「36(10s)2）校验:1.1断路器校验a开断电流iNBr50Ik1I1"I2"Ts"13.69513.69518.01131.396INBr22b关合电流iNCL125ish丄.ish1ish2小ishs36.8436.84121.5584.455incl22c热稳定校验22Itt50237500b关合电流iNCL55(KA)b关合电流iNCL55(KA)Qk短路时间td5tkd50.0655.065(s)I"I31.39611.9932.62查《发电厂电气部分课程设计参考资料》P112图5-1tz6.15+0.065=6.215td1s则tdztz6.15I1()i1()2》()s3.8383.838舟8.63411.9932211.99326.215893.92Itt7500222Itdz11.99326.15884.567Itt1.2隔离开关校验a动稳定校验iNCL85(KA)1•ishish1ish2ishs84.455iNCL2b热稳定校验222Itt3621012960Itdz884.567变压器高压侧最大持续电流：Igmax0.087(KA)1)选择：根据《发电厂电气部分》P491表2-18选得设备名称设备型号额定开断电流(KA)极限通过电流(KA)热稳定电流(KA)分闸时间(s)断路器SW4-220-100018.45521(5s)0.06隔离开关GW5-220-20025.510(5s)2)校验：1.1断路器校验a开断电流Inb「18.4(KA)IKI2"IS"0.2920.5230.815INBrb关合电流iNCL55(KA)ishs0.523IKI2"IS"—0.2920.2920.864INBrsh2ishs0.7681.3752.143iNCLc热稳定校验22Itt211252205I"I0.8150.6161.323QkI2tdz220.61624.581.73811t2205短路时间td5tkd50.065.06(s)查《发电厂电气部分课程设计参考资料》P112图5-1tz4.520.064.58td1s则tdztz4.58222Itdz0.61624.581.738Itt1.2隔离开关校验a动稳定校验iNCL25.5(KA)ishish2ishs2.143iNCLb热稳定校验222Itt1025500Itdz1.738母联处最大持续电流：Igmax°.174(KA)1）选择：根据《发电厂电气部分》P491表2-18选得设备名称设备型号额定开断电流（KA）极限通过电流（KA）热稳定电流（KA）分闸时间（s）断路器SW4-220-100018.45521(5s)0.06隔离开关:GW7-220-6005521(5s)2)校验：1.断路器校验a开断电流Inb「18.4(KA)a开断电流iNBr18.4(KA)a开断电流iNBr18.4(KA)ishish1ish2ishs/20.7680.76813752.224izcL2c热稳定校验It2t2122205QkI()21()s0.5624.860.1681.524短路时间td5tkd50.060.16804480.5622Itt22055.06(s)I"0.8461.51I0.56查《发电厂电气部分课程设计参考资料》P112图5-1tz4.80.064.86td1s则tdz4.861.2隔离开关校验a动稳定校验iNCL55(KA)1375ishish1ish2ishs24iNCLb热稳定校验222Itt2152205Itdz1.524高压侧出线处于母联处相同即最大持续电流：Igmax0.174(KA)1）选择：根据《发电厂电气部分》P491表2-18选得设备名称设备型号额定开断电流（KA）极限通过电流（KA）热稳定电流（KA）分闸时间（s）断路器SW4-220-100018.45521(5s)0.06隔离开关GW7-220-6005521(5s)2）校验：1.断路器校验gmax0.192(KA)IkI2"Is"上0.2920.2920.864INBr22关合电流INCL55(KA)'shish1ish2ishs/20.7680.76813752.224Incl2c热稳定校验It2t2122205II()21()s0.1680.16804480.562短路时间tdtkd50.065.06(s)I"I逊1.510.56查《发电厂电气部分课程设计参考资料》P112图5-1tz4.80.064.86td1s则tdz4.86QkI2tdz0.5624.8621.524Itt22051.2隔离开关校验a动稳定校验iNCL55(KA)ishish1ish2ishs/20.7680.7681.3752热稳定校验b2.224inclIt2t21222052tdz1.5247•厂备用高压侧最大持续电流：Igmax0.115(KA)设备名称设备型号额定开断电流（KA）极限通过电流（KA）热稳定电流（KA）分闸时间（s）断路器ZN22-10-12504010040(4s)0.065隔离开关GN30-10-125010040(4s)1）选择：根据《发电厂电气部分》P491表2-18选得2)校验：1•断路器校验a开断电流iNBr40(KA)IkI1"I2"IS13.69513.6958.01135.401INBrb关合电流iNCL100(KA)ishish1ish2ishs36.8436.8421.5595.23iNCLc热稳定校验It2t40246400II()1I()2I()S3.8383.8388.63416.31短路时间td5tkd50.0655.065(s)匕35.4012,!7I16.31查《发电厂电气部分课程设计参考资料》P112图5-1tz5.630.0655.695td1s则tdz5.695222QkI2tdz16.3125.6951514.96Itt64001.2隔离开关校验a动稳定校验iNCL55(KA)ishish1ish2ishs36.8436.8421.5595.23inclb热稳定校验222Itt40246400Itdz1514.968.支配负荷最大持续电流：I1）选择：根据《发电厂电气部分》P491表2-18选得设备名称设备型号额定开断电流（KA）极限通过电流（KA）热稳定电流（KA）分闸时间（s）断路器1ZN12-10-16005012550(3s)0.065隔离开关GN2-10-300010070(5s)2）校验:1•断路器校验a开断电流Inb「50（KA）IkI1"I2"Is13.69513.6958.01135.4011NBrb关合电流incl125(KA)ishish1ish2ishs；36.8436.8421.5595.23iNCLc热稳定校验lt2t50237500Ii()1l()2l()S3.8383.8388.63416.31短路时间td5tkd50.0655.065(s)l"35.4012.171116.31《发电厂电气部分课程设计参考资料》P112图5-1tz5.630.0655.695td1s则tdz5.695Qkl2tdz16.3125.6951514.96lt2t64001.2隔离开关校验a动稳定校验iNCL100(KA)ishish1ish2ishs36.8436.8421.5595.23inclb热稳定校验222Itt4046400Itdz1514.96