电工电子学课后习题答案

1、电工电子学课后习题答案目录电工电子学课后习题答案1第一章电路的基本概念、定律与分析方法2练习与思考2习题4第二章正弦交流电14课后习题14第三章电路的暂态分析29第四章常用半导体器件41第五章基本放大电路43第六章集成运算放大器及其应用46第七章数字集成电路及其应用54第八章Multisim简介及其应用65第九章波形的产生与变换65第十章数据采集系统67第十一章直流稳压电源69第十二章变压器与电动机71第十三章电气控制技术77第十四章电力电子技术. 80练习与思考1.4.2（ b）- +36V6V-1.4.2(c)6A51.4.3（ a）1A5Uab 5 5 2 15VRab 51.4.3 (

2、b)6第一章电路的基本概念、定律与分析方法a-+a42V6bbaa2A5+40Vb-baa+52A15V-bba+42V-bU ab66642VR6ab1.4.3 (c)a+-540VbUab UR 10 6 5 10 40VR5ab1.4.3 (d)a3+-us 6 Vbus2us14KVL : 2 1uab320uabus VRab361.4.4 (2)abR2R4R3R1R2R1+-15V6V5V5V+9V-15Vb15Vb24R2R415Vb5Vb34R3R1KCL : 1234VbVbVbVbR1R2R4R3求方程中 Vb2V b =V b1V b +9 = V b +9R 250k

3、R1100kKCL:V b= Vb9V b1V50k100kKVL:650KI+100KI9=0100KI=15 I=1A10kV b =650k1=1V10k习题1.1 （ a）（ b）xx15427 A0.40.70.3 A(C)x4x20.30.20.20.1A0.230x30.20.10.3 Ax2x10.30.60.9 A1.230.010.30.31A49.610.319.3A60.39.39.6 A1.3P114228发出功率P211010吸收功率P3428吸收功率P4(110)10吸收功率P发=28P发 =P吸吸P =281.6R612050mv（ a) u6V(b)u R12

4、60R4V601201.7（ a） us 1 4 4V(b)I s2 A5 us2 20 us9V1.8us1221014VI s21021A10P121428P2101101.9u1236.34Rx168I10.45 AI 20.3 A I 30.450.3I 30.150.15 A6.346.310Ry0.45174.41.10(a):u2u116V(b):u21651.6V455(c):u21.650.16V455(d):u20.165450.016V51.11u21u1R2Rp8.41VR1R2Rpu22u1R25.64VR1R2Rp1.12RCD630.56 3 RB D =0.5R

5、A D1990.5199.5I11015mA I 25mA2I 3534.2mA3.6I 450.60.8mAI 2 I 33.6uAD10 199.51.995mVuBD =1 5=5mVPs10 1.9950.019951.13 (a)AAAR3AR22A25A2+110VBB-B(b)AA3+15V9-+63V-12V-B+B1.153+I4A6V33A 3-1.5 3+I6V1.5V-I1.561A1.531.16I3-10V310+10V2-53I+1A1.5 6V-I 310101A10532I1I s1I 311 0I 0202 AI 2121AI 41623A63I 51331

6、 A631.1712V1 a+-2A 3 2A6I2b2-a+I4A2b22V+-I8V2-I821A2221.18I1 I 2I 3KVL :u1I1 R1 I 3 R30I3 R3I 2 R2 u20I116I 26I 3227575751.19n2I118I 3I 2KVL :14020I16I 20I 36I 20I14 A I 210 A I 3 12 Au120I 180Vu26I 260V电压源 P1404560发出功率电流源 P6018108发出功率1.20n2I1I 2 +10IKVL :0.8 I 1 1201160.4 I 2 00.4 I 21164I 20I18.75

7、 A I 29.375 A I 328.125 A120V : P1209.3751125116V : P120160.75101510 A : P10428.1251175RL : PI 2 R28.125 243078.1251.21I10.5I 2I12 3V21 V233I 2V24V2271.22R1R3usR2I 2+usR4-I 21us6R40.1AR240 20R1R2I 2R3R4I sI sI 20.10.10.2AI 22I sR40.320R20.1AR440 201.23+-10.5 I 311V1I 31110.25A0.50.511110.5 I 3 11I s

8、I 322110.510.5 A0.52I 30.250.50.75 A1.24 (a)KCL : I1I 2I 30KVL 1: 2I11301202I 2 0KVL 2 : 2I 21204I 30I115A, I 210 A, I 325 A(b) 开关合在b 点时，求出20V 电压源单独作用时的各支路电流：I 1I 3 22I 2 4b+20V-I1220444 A242I 22046 A22I 320422 A2242所以开关在b 点时，各支路电流为：I115411AI 210616AI 325227A1.25（b）等效变换+A-22.5A3ABU ab (3 2.5) 211V（c

9、）等效变换aa4A4A2bbU ab(42)1.59V1.26戴维宁 :ua220 1110V2Rab25I L110122 A255015诺顿 ：I ab22022 A505Rab25I L222522 A52550151.28R1R22AR3R4+ -U 10V(1) 求二端网络的开路电压：bR2a2AR3R4+ -U10VU ab104I10242V U ab104I10242V(2) 求二端网络的等效内阻（电压源短路、电流源开路）RabR24(3) 得到戴维南等效电路+RabR1U abI1U abR12 A 0.154 ARab131.32 （ a）I1I 2I3I150 VAI25

10、0 VA I 3VA1052050VA50VAVA10520VA100V72.3.2(a) 取电源为参考向量?UI R?U 2I (jX c )tan60IRR3IX CX cX CR , 又X C =132fc2 fcR=3（ b）?U 2I ( jX c )?U RI Rtan 60IR3IX CX LR , 又 X L =2 fL3R32=fL第二章正弦交流电课后习题2.3.2(a) 取电源为参考向量?UI R?I60?U 2（ b）?U 260?U 2I (jX c )? tan60IRR3U RIX CXc?XCR, 又 XC =13fcU122 fcR= 3?U 2I ( jX c

11、 )?U RI Rtan 60IR3IX C?R , 又X L =2 fLU 1X L?3?RI=3U R2fL习题2.2?I15j 5, I152 Ai110sin(1000 t 45 ) AI152 45 A?I25j55245 A?i210sin(1000t45 ) AI3?I1?5j 552135 AI3i310sin(1000 t135 )A?I45j552135 AI 4I 2i410sin(1000t135 ) A2.3?U?U2U 130（ 1）?U 1630 VU 2630 Varctan8 =536?U =U 1 +U 2 =10Vu102 sin(t)V(2)?I 260

12、30?I?I 1?I11030A I 210 60 Aarctan1 =45?102(4530 ) 10 275 AIi20sin(t75 ) A2.4?(a) 以电流 I 为参考向量?U L?U?U R10arctan=45U10 2V14.1V?U10 245 V?（ b）以电流I 为参考向量I?U R?UU CU 2U C2U R2U C100260280Vu2U sin(t)i12I1 sin(t90 ) Ai22I 2 sin(t45 ) A?(c) 以电流 I为参考方向?U L?UI?U C?U(200100)9010090 VU100V?（ d）以电压 U为参考方向?I R?U?

13、II LII R2I L2I L52423A?（ e） 以电压 U为参考方向?I C?I? UI RI52525 2A7.07A?（f ）以电压 U 为参考方向?I C?U?III LI CI LI CI18A2.5 （ 1）I C72 sin(t ) A?I L70A,2 f314rad / sX LL31.4?3U LI CjL7 0314 100V219.80 VuL309.9 sin(t)V310（ 2）uL309.9sin(t)V310I LU L1273 4 AL314100X L2.6(1)?U c2200 VU c220VXC11796.2C23.1406ICU c220X c

14、0.28A796.2?IC0.28ic0.39sin( t) A?(2) U c0.10796.279.6V2.9 (1)u2202 sin( t)V?U2200 V2f314rad / si102 sin( t) A?I100 A（ 2）?ZU2200?1022 0 11 11 3 jI0LX L11 3260.7mH50（ 3）SUI 220 102200V ? APUI cos220 10 cos6001100Wsin2200sin 6001905var2.10+Ru1+C u2(1)电容两端f=HZ?以 I1 为参考向量=-600Rcos2k11K2X csin2k3 ) 170711

15、2X c0.1uFcX cc（ 2）电阻两端?I1?0U RU 230?U 1U 0=-300Rcos =2k3 =17072X c =sin =-2K（ 1） 1000=12c0.16uFc2.12+R?LUC-RLCZ=R+(X LX C ) j10UV2.13UV?200VU100i Ru1002 sin(1000t200 )R3000.47sin(1000t 200 )X LL10000.4400?0U10020I L0.25jX L400900i L0.35sin(1000t700 ) AXC11500C1000210 6?0?U100I c200.2jX C500900ic0.28

16、sin(1000t1100 ) A1111ZRjX LjX c1(j1j1 )30040050900.0030.0005j0.00390?0?U1000 AI00.33Z3002.14?以U 为参考向量?I C?I U?I L0 A0 0 AX CX LI CI L?I 1I CI LI RI RI RU10 AU10RVRI 3I CU10RX C10 AXC?450 AI 2I RI C10I 2102A2.15(1)ZRjX C30j110002510 63040 j50530uRiS R300（0）V2 sin 1000t-30?300 AI s10?30030040900U C I

17、s (jX C )10404001200VuC4002 sin(1000t1200 )V?300530830VUI s Z1050500(2)u5002 sin(1000t830 )V（ 3）PU R IS300 10 3000WQQCU C I S400 104000VarSUI S500105000V ? AP S cos（-530）=3009WQ Ssin（-530）=-3993Var2.18?U L?I U R?U CRUR82I4LU L12I34L30.3H10?UU RU LU C8(12U C ) j2(12 U C )2102U C6V或 18VXCU C1.5 或I1=X

18、CC10.067F 或1=0.022 FC101.510 4.52.19 (a)(1)Z1j3j 6182 jj3j69 j(2)j1 j2 j4 3 j5370?0?U100370 AI2Z5370?370370 VU1248?370900530 VU 2248?370900530VU3212?3709001270VU 4224?0?U44127370 AI11.33j33900?0?U 44127370 AI20.67j66900(3)PUI cos102cos( 370 )16W(b) (1)Z1(j 4)(j 6)242.4 jj3j 610 jj2 j2.4 j43 j5370(2)

19、?0?U100370 AI2Z5370?370900370VU1242?370370VU 2248?370900530 VU 324?3709001270VU 422.44.8?0U 44.8127370 AI11.24 j900?0?U 44.81270I 20.8j 6690037 A(3)PUI cos102cos(370 )16W2.20Z155 j52450Z2(55 j )j10（10 j5-5 j )I1U 2= 100 =10AZ210A 读数为10AZ=10+10 j102450U 1I 1Z21002VV1读数为141.4V2.23XC111C10410210 6Z11 (

20、 j )1j24501 1 j1(j)j22 2XLL1041041Z1jZ11.50.5 j2.24?0U c100I c0.5Aj 22900?0U c1 00I R1AR 1? ?II cI R0.50 1010.5 j A1.10 A?U RI R (1 0.5 j ) 2 2+ j V?U LIj 2(1 0.5 j ) j 22 j11+2 jV?2 j 1 2 j 1 2 3 j 3.610 VU U R U L U cPUI cos3.611.1cos(00W2.29，P1.21KPUI cos1 cos1 = UI112200.51 600， 2 24.50P2 (tan1 - tanC）U= 1.21K (1.7320.456)1022uF23.14502202P1K4.54 AI220U RS UI380 4.541727.3V ? AS