TRNG I HC BCH KHOA H NI VIN IN T - VIN THNG

THI MN: in t cng sut Ln thi: Cui k Ngy thi: 9/6/2014 Thi gian lm bi: 60 pht (Khng s dng ti liu. Np thi cng vi bi lm)

K duyt

Trng nhm Mn hc: Trng B mn:

H v tn sinh vin: MSSV: Lp:

Cu 1 (3 im)

Cho mch sau:

1. Mch trn l mch g. Nu nguyn l iu khin chnh. 2. V gin theo thi gian cho :

taitaiGGGcba IVVVVVVV ,,,,,,, 321 trong trng hp gc m

)45(4/ v

a. R=200, L=0H b. R=0, L=10H

Bit: in p ln nht ca Va,Vb,Vc l VV 3800 , tn s 50Hz.

3. Tnh in p v dng in trung bnh trong mi trng hp trn.

Cu 2 (3 im)

Cho mch sau:

1. Mch trn gii quyt vn g. Nu nguyn l lm vic.

2. Gi thit: R=200, in p u vo l ngun xoay chiu dn dng 220V, 50Hz.

3. Xung iu khin T1 c chu k 50Hz, gc m l =90 . Xung iu khin T2 tr so vi T1 180 .

4. Tnh in p hiu dng trn ti. 5. V dng sng ca in p ti cho trng hp

trn.

Cu 3 (2 im)

1. Nu nguyn l lm vic ca mch trn. 2. Gi s s vng dy cun s cp bin p l N1=100 vng, s vng dy cun th cp l N2=500 vng.

Tnh ton cc thng s cn li ca mch c in p 20V.

3. Trong trng hp ngun Vin c thay th bng 1 t, khi mch hot ng th in p Vin s gim dn theo thi gian. Nu phng php in p u ra trn ti vn c gi tr n nh nh c. (C th v s khi nu cn).

Cu 4. (2 im) Gi s cho ngun xoay chiu dn dng 220V, 50Hz. Thit k mch v tnh ton cc linh kin to ra in p xoay chiu 10V, 1000 Hz.

Ch : Khi v dng sng ca in p, dng in, cn ch r gi tr ca cc nh v cc gi tr thi gian (v d thi gian qua gc 0, thi gian ng/ct). Li gii thch ngn gn (2-4 cu). ng khung kt qu cui cng (nu l s), ghi r n v.

s: 1 Tng s trang: 1

TRNG I HC BCH KHOA H NI VIN IN T - VIN THNG

THI MN: VI X L Ln thi: Cui k Ngy thi: 9/6/2014 Thi gian lm bi: 60 pht (Khng s dng ti liu. Np thi cng vi bi lm)

K duyt

Trng nhm Mn hc: Trng B mn:

H v tn sinh vin: MSSV: Lp:

Cu 1 (3 im)

Cho mch sau:

4. Mch trn l mch g. Nu nguyn l iu khin chnh. 5. V gin theo thi gian cho :

taitaiGGGcba IVVVVVVV ,,,,,,, 321 trong trng hp gc m

)45(4/ v

a. R=100, L=0H b. R=0, L=1H

Bit: in p ln nht ca Va,Vb,Vc l VV 3800 , tn s 50Hz.

6. Tnh in p v dng in trung bnh trong mi trng hp trn.

Cu 2 (3 im)

Cho mch sau:

6. Mch trn gii quyt vn g. Nu nguyn l lm vic.

7. Gi thit: R=100, in p u vo l ngun xoay chiu dn dng 220V, 50Hz.

8. Xung iu khin T1 c chu k 50Hz, gc m l =90 . Xung iu khin T2 tr so vi T1 180 .

9. Tnh in p hiu dng trn ti. 10. V dng sng ca in p ti cho trng hp

trn.

Cu 3 (2 im)

1.Nu nguyn l lm vic ca mch trn. 2.Gi s s vng dy cun s cp bin p l N1=100 vng, s vng dy cun th cp l N2=400 vng.

Tnh ton cc thng s cn li ca mch c in p 30V.

3.Trong trng hp ngun Vin c thay th bng 1 t, khi mch hot ng th in p Vin s gim dn theo thi gian. Nu phng php in p u ra trn ti vn c gi tr n nh nh c. (C th v s khi nu cn).

Cu 4. (2 im) Gi s cho ngun xoay chiu dn dng 220V, 50Hz. Thit k mch v tnh ton cc linh kin to ra in p xoay chiu 10V, 2000 Hz.

Ch : Khi v dng sng ca in p, dng in, cn ch r gi tr ca cc nh v cc gi tr thi gian (v d thi gian qua gc 0, thi gian ng/ct). Li gii thch ngn gn (2-4 cu). ng khung kt qu cui cng (nu l s), ghi r n v.

s: 2 Tng s trang: 1