电路原理习题课课件.

电气信息学院SEEISchoolofElectricalEngineeringandInformationSichuanUniversity习题课6、9、10、11章电气信息学院SEEISchoolofElectricalEngineeringandInformationSichuanUniversity6.2P已知在50uH电感中的电流为（a）求t0时电感上的电压（采用无源符号约定）（b）求当t=200ms时电感端的功率（单位用微瓦）（c）在200ms时，电感是吸收还是释放功率。（d）求在200ms时存储在电感中的能量（单位微焦（e）求存储在电感中的最大能量（单位用为焦）和所发生的时刻（单位用毫秒）Aitl1018te电气信息学院SEEISchoolofElectricalEngineeringandInformationSichuanUniversity（a）求t0时电感上的电压（采用无源符号约定）（b）求当t=200ms时电感端的功率（单位用微瓦）i(200ms)=18(0.2)()=487.21mAv(200ms)=900()(1−2)=−121.8μVp(200ms)=vi=(487.21×)(−121.8×)=−59.34μW（c）在200ms时，电感是吸收还是释放功率。释放功率uVtedtiLVt)101(900d102e2e310610电气信息学院SEEISchoolofElectricalEngineeringandInformationSichuanUniversity（d）求在200ms时存储在电感中的能量（单位微焦i(200ms)=487.21mA(由[b]得)（e）求存储在电感中的最大能量（单位用为焦）和所发生的时刻（单位用毫秒）电流最大时能量最大由t=0.1smjL93.5i2120ddtiujwmAe96.10)66218.0)(10*50(2118.662)1.0(18i26max1max电气信息学院SEEISchoolofElectricalEngineeringandInformationSichuanUniversity6.15•如图（a）所示的0.5uF的电容初始电压是-20V。电容电流波形如图（b）所示。（a）在t=500us时，存储在电容中的能量是多少（b）在t=时，存储在电容中的能量是多少电气信息学院SEEISchoolofElectricalEngineeringandInformationSichuanUniversity（a）（b）ujCVVedteVtVidtCVtttt7.332161.1120200010*1002010*50010*5.01)0(1210*5000200032000310*50006066ujVV22530*10*5.0*21)(302050)(26-）（电气信息学院SEEISchoolofElectricalEngineeringandInformationSichuanUniversity6.40（a）证明图中两个耦合线圈，可以由一个具有电感的线圈来代替（b）证明如果标有的线圈两端反向连接，则MLLLab221MLLLab2212L电气信息学院SEEISchoolofElectricalEngineeringandInformationSichuanUniversity（a）（b）)2()2(212121MLLLdtdiMLLdtdiMdtdiMdtdiLdtdiLVabab)2()2(212121MLLLdtdiMLLdtdiMdtdiLdtdiMdtdiLVabab电气信息学院SEEISchoolofElectricalEngineeringandInformationSichuanUniversity9.11用向量的概念将下列正弦函数写成三减函数的形式（a）（b）)70200cos(15)160200cos(3000tty)70200cos(60)2050(in9000ttsy)56.170200cos(38.2856.17038.287015160300000tyY)16.94-50cos(33.14116.94-33.14170-60110900000tyY电气信息学院SEEISchoolofElectricalEngineeringandInformationSichuanUniversity（c）（d）)150cos(10s10)30cos(1000ttinty)305000cos(75)1105000sin(25)605000cos(50000ttty)52.1705000cos(7.1652.1707.1630-75-202560-5000000tyY00901015010901030100000yY电气信息学院SEEISchoolofElectricalEngineeringandInformationSichuanUniversity9.13•频率为80KHZ的正弦电压，相位角为0，幅值为25mV，将此电压加到电容两端，稳态电流的幅值为628.32uA。（a）求电流的频率（b）求电流的相位角sradf/82.50265410*16023003-03-03909010*25010*25/1010*25iCCjCjI）（电气信息学院SEEISchoolofElectricalEngineeringandInformationSichuanUniversity（c）求电容的容抗（d）求电容值（单位微法）（e）求电容的阻抗79.3979.3910*32.62810*25110*2510*32.628633-6-CXCCuFCC05.010*05.0)10*160)(79.39(1)(79.3916379.39)1(jCjZC电气信息学院SEEISchoolofElectricalEngineeringandInformationSichuanUniversity9.24（a）如图所示，当阻抗为纯电阻时，求电路的频率（b）求在（a）频率下的值abZabZ电气信息学院SEEISchoolofElectricalEngineeringandInformationSichuanUniversity（a）（b）sradLLCRRLCRCRCLZIRCjLCRCjLCRCjLCLjRLCRRLjCjRLCRLjRLjRLjCjLjRCjZabab/500250000)4.0()10*20)(4.0(20020000)(m))(())(()(112622222222322322222100200200)200(200100)500(jjjZab电气信息学院SEEISchoolofElectricalEngineeringandInformationSichuanUniversity9.33如图，若，和，求Z值VjVg50100AjIg2030VjV301401电气信息学院SEEISchoolofElectricalEngineeringandInformationSichuanUniversity221030)30140()50100(103001612)30140()3040(1030140)2030(304001612)30140(520)50100(jjjjZAjIjjjjjjIVjVjjVjVjVZZaaaa电气信息学院SEEISchoolofElectricalEngineeringandInformationSichuanUniversity9.36如图所示电流向量为。（a）求（b）若的表达式。（a）（b）bImA0025cbaIII,,)(),(),(,/1500tititisradgca求mAmAjIIIImAmAjjjImAmAjjjIVjjVcbagcab00017.2277.1455513557.269.552550100050255013.25100806025050025502550)025.0)(10002000(mAtimAtimAtigca)17.221500cos(77.145)57.261500cos(9.55)13.531500cos(100000电气信息学院SEEISchoolofElectricalEngineeringandInformationSichuanUniversity9.43如图所示正弦电压为50sin400tV。（a）求a、b两点间的戴维南等效电压（b）求a、b两点间的等效阻抗（c）画出戴维南等效电路电气信息学院SEEISchoolofElectricalEngineeringandInformationSichuanUniversity（a）（b）去掉电压源（c）VjjjjjjVVjjCjjjLjabTH1020)50()16080(320160808010*25.31*4001116010*400*400631286416080320jjjZZabTH电气信息学院SEEISchoolofElectricalEngineeringandInformationSichuanUniversity9.48如图所示，求ab两点间的诺顿等效电路短路电流：AjIIIVIIjVjIIjVSCNxSCxSCx46100)(1054040)(10111电气信息学院SEEISchoolofElectricalEngineeringandInformationSichuanUniversity9.48如图所示，求ab两点间的诺顿等效电路开路电压：20204640200402001054010410104040-jjjZVjIjVVVIVAjjINxOCx电气信息学院SEEISchoolofElectricalEngineeringandInformationSichuanUniversity9.57如图所示，若用节点电压法求的稳态表达式。VtvVtvgg)69.33400cos(03.18)13.143400sin(250201)(0tvVjVVjVjjCjjjLjgg101569.3303.18201513.532550)10*50(*400120)10*50)(400(020163tVtvVjjVVjjV400cos15)(015020)1015(15050)2015(000000电气信息学院SEEISchoolofElectricalEngineeringandInformationSichuanUniversity9.64如图所示，若，用网孔电流法求的稳态表达式。tVvg5000cos750V50)10*4(*50001550)10*110(500020)10*4(500063231jjCjjjLjjjLj)(550100)2010(05501005000750IIjIIjIjIIjaaatVtvjIVAjIaa5000sin25)905000cos(25902525105.20000电气信息学院SE