5∠60° 0.149∠-3.4°A Z33.54∠63.4° UR=RI=15×0.149∠-3.4°=2.235∠-3.4°V UL=joLI=56.5∠90×0.149∠-34°=842∠864V Uc=-j 26.5∠-90°×0.149∠-3.4°=3.95∠-93.4°V oc 则 U L i=0.149y2c0s(0t-34)A ln=2235√2cos(0t-34)V 3.4 un=842√2cos(0+86.6°)V lc=3.95√2cos(0t-934)V U U1=842>U=5,分电压大于总电压。 相量图 DOWNUP DOWN 0.149 3.4 A 33.54 63.4 5 60 o o o =  −   = = • • Z U I 则 i = 0.149 2 cos(ωt − 3.4 o ) A UL=8.42>U=5，分电压大于总电压。 U  UL  UC  I R  U  j -3.4° 相量图 15 0.149 3.4 2.235 3.4 V o o = =   − =  − • • U R R I 56.5 90 0.149 3.4 8.42 86.4 V o o o = =   − =  • • U L jL I 26.5 90 0.149 3.4 3.95 93.4 V C 1 o o o = − =  −   − =  − • • UC j I  2.235 2 cos( 3.4 ) V o uR = ω t − 8.42 2 cos( 86.6 ) V o uL = ω t + 3.95 2 cos( 93.4 ) V o uC = ω t −