前推回代法计算流程要看懂前推回代法计算程序，报告叙述计算原理及计算流程。绘制计算流程框图。确定前推回代支路次序（广度优先，或深度优先），编写前推回代计算输入文件。进行潮流计算。下列为节点配电网结构图及系统支路参数和系统负荷参数表。图1-2节点配电网结构图表1系统支路参数支路R(Ω)X（Ω.）B/2(TK)（S）1~23.3673.6850.02~32.3562.5410.03~41.1451.280.04~54.5245.040.02~60.8561.140.06~72.7452.9650.02~83.7434.2510.08~92.2372.7560.03~104.144.6960.03~111.3281.7630.011~122.4362.8660.04~133.5213.9660.0表2系统负荷参数节点编号节点类型节点初始电压（kV）Pi（MVA）Qi（MVA）PAGE\*MERGEFORMAT121根节点10.4002中间节点10.00.03420.03013中间节点10.00.06930.06424中间节点10.00.08450.07635叶节点10.00.02950.02616中间节点10.00.04740.04097叶节点10.00.11760.09578中间节点10.00.09460.08579叶节点10.00.09160.085910叶节点10.00.02710.022911中间节点10.00.06960.064312叶节点10.00.06760.057913叶节点10.00.02980.0242主程序清单：[PQ,FT,RX]=case114();%调用数据文件NN=size(PQ,1);%节点数NB=size(FT,1);%支路数数V=PQ(:,1);%V初始电压相量maxd=1k=1whilemaxd>0.0001PQ2=PQ;%每一次迭代各节点的注入有功和无功相同PL=0.0;fori=1:NBkf=FT(i,1);%前推始节点号kt=FT(i,2);%前推终节点号x=(PQ2(kf,2)^2+PQ2(kf,3)^2)/V(kf)/V(kf);%计算沿线电流平方APQ1(i,1)=PQ2(kf,2)+RX(i,1)*x;%计算支路首端有功/MWRX(i,1)~RPQ1(i,2)=PQ2(kf,3)+RX(i,2)*x;%计算沿支路的无功损耗/MvarRX(i,2)~XPQ2(kt,2)=PQ2(kt,2)+PQ1(i,1);%用PQ1去修正支路末端节点的有功P单位MWPQ2(kt,3)=PQ2(kt,3)+PQ1(i,2);%用PQ1去修正支路末端节点的有功Q单位MvarPL=PL+RX(i,1)*x;PAGE\*MERGEFORMAT12endangle(1)=0.0;fori=NB:-1:1kf=FT(i,2);%回代始节点号kt=FT(i,1);%回代终节点号dv1=(PQ1(i,1)*RX(i,1)+PQ1(i,2)*RX(i,2))/V(kf);%计算支路电压损耗的纵分量dv1dv2=(PQ1(i,1)*RX(i,2)-PQ1(i,2)*RX(i,1))/V(kf);%计算支路电压损耗的横分量dv2V2(kt)=sqrt((V(kf)-dv1)^2+dv2^2);%计算支路末端电压/kVangle(kt)=angle(kf)+atand(dv2/(V(kf)-dv1));%计算支路endmaxd=abs(V2(2)-V(2));V2(1)=V(1);fori=3:1:NNifabs(V2(i)-V(i))>maxd;maxd=abs(V2(i)-V(i));endendmaxdk=k+1PQ1%潮流分布即支路首端潮流MVAV=V2%节点电压模计算结果kVangle%节点电压角度计算结果单位度PL%网损单位MWendclear输入文件清单：function[PQ,FT,RX]=case114()PQ=[%节点电压有功无功10.40010.00.03420.030110.00.06930.0642PAGE\*MERGEFORMAT1210.00.08450.076310.00.02950.026110.00.04740.040910.00.11760.095710.00.09460.085710.00.09160.085910.00.02710.022910.00.06960.064310.00.06760.057910.00.02980.0242];FT=[%首端末端54134431031211113766298823221];RX=[%RX4.5245.043.5213.9661.1451.284.144.6962.4362.8661.3281.7632.7452.9650.8561.142.2372.7563.7434.2512.3562.5413.3673.685];计算过程maxd=1PAGE\*MERGEFORMAT12k=1maxd=0.1780k=2PQ1=0.02960.02620.02990.02430.14430.12720.02720.02300.06780.05810.13780.12300.11820.09640.16600.13780.09200.08630.18900.17480.38470.34390.80990.7260V=Columns1through810.40009.88079.82209.96729.97349.97019.93909.8550Columns9through139.95569.97809.96009.96689.9799angle=Columns1through8PAGE\*MERGEFORMAT1200.30110.39860.42110.43870.34210.39160.3878Columns9through130.42250.41730.44440.47470.4400PL=0.0471maxd=0.1787k=3PQ1=0.02960.02620.02990.02430.14430.12720.02720.02300.06780.05810.13780.12300.11820.09640.16600.13780.09200.08630.18900.17490.38490.34420.81120.7274V=Columns1through810.40009.87989.70049.78869.94059.85049.90899.7338Columns9through13PAGE\*MERGEFORMAT129.81009.79969.78139.92679.9470angle=Columns1through800.30110.40110.42440.44210.34310.39290.3899Columns9through130.42570.42040.44860.47910.4434PL=0...
VIP
