电工学答案（秦曾煌）：dz18

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?18.1.15.,,,,,,,,,,,,,,,,,,,,,,,,,,,,,3
?18.1.25.,,,,,,,,,,,,,,,,,,,,,,,,,,,,,3
?18.1.35.,,,,,,,,,,,,,,,,,,,,,,,,,,,,,4
?18.1.75.,,,,,,,,,,,,,,,,,,,,,,,,,,,,,4
?18.1.85.,,,,,,,,,,,,,,,,,,,,,,,,,,,,,5
?18.2?
ro.,,,,,,,,,,,,,,,,,,,,,,,,,,,,,5
?18.2.45.,,,,,,,,,,,,,,,,,,,,,,,,,,,,,5
?18.3?°
@×aè÷.,,,,,,,,,,,,,,,,,,,,,,,,,6
?18.3.15.,,,,,,,,,,,,,,,,,,,,,,,,,,,,,6
?18.3.45.,,,,,,,,,,,,,,,,,,,,,,,,,,,,,7
?18.3.65.,,,,,,,,,,,,,,,,,,,,,,,,,,,,,7
1
List of Figures
1518.1.1m.,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,3
2518.1.7m.,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,4
3518.2.4m.,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,6
4518.3.1m.,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,6
5518.3.6m.,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,8
2
18°°°
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18.1???
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18.1.1
m1?
X?RL = 80?
°
@èaVV￥
1110V

kp
(1)°
@è
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VA￥

(2)?
@è
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(3)?
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@￥μr′b=5￥?_a?-
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[333]
m1:518.1.1m
(1)
Io = UoR
L
= 11080 A = 1:38A
(2)
Iom = …Io = 3:14￡1:38A = 4:33A
(3)
U1 = Uo0:45 = 1100:45V = 244:4V
(4)
I = 1:57Io = 1:57￡1:38A = 2:16A
18.1.2
??m18.1.1
U￥?M?o?
@è
^?
X?Ma=Q§è
@￥μ
r′U = 30V
μèERL = 100?

kù
(1)
{èa
{è
@￥
ü (
′UoIoò1

$(2)?è÷èao?§10%
=5?
s￥KúQ_èa1

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[333]
3
(1)
Uo = 0:45U = 0:45￡30V = 13:5V
Io = UoR
L
= 13:5100 A = 0:135A
(2)
UDRM = 1:1p2U = 1:1￡1:414￡30V = 46:7V
18.1.3
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@è
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k9
5b
[333]
(1)
Uo = 0:9U = 0:9￡30V = 27V
Io = UoR
L
= 27100A = 0:27A
(2)
UDRM = 1:1p2U = 1:1￡1:414￡30V = 46:7V
18.1.7
m2
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@è
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Uo = 2p2U

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18.1.8
μBè3è÷
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T?
@b?1pμ°
@èaUo = 20V
μè
@Io = 200A
(1)
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[333]°??V18.1.1
(1)Ma=Q§Mèa￥μr′1
U = Uo2:34 = 202:34V = 8:55V
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U = 1:1￡8:55V = 9:4V
Ma=Q§Mè
@￥μr′1
I = 0:82Io = 0:82￡200A = 164A
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1
S = 3UI = 3￡9:4￡164V ￠A = 4624:8V ￠A … 4:6kV ￠A
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￥Mab
(2)YV
5￥è
@
ü (′1
ID = 13Io = 13 ￡200A = 66:7A
50??
H?
s￥KúQ_èa1
UDRM = 2:45U = 2:45￡9:4V = 23V
Vê¨100Aa50V￥?
@5b
18.2
r
r
rooo
18.2.4
m3 μ…?RC
ro￥?
@è
^?
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@èaU = 6V
?1pμ
{èaUo = 6V
μ
{è
@Io = 100mA

k9
roèERb
[333]
5
m3:518.2.4m
|Uc1 = 1:2U = 1:2￡6V = 7:2V
#R = Uc1?UoI
o
= 7:2?6100￡10?3? = 12?
18.3°°°
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18.3.1
×a=5×aè
^?m4
U
X?u = 28:2sin!tV
Uo = 6V
RL =
2k?
R = 1:2k?b
kp
(1)S1 7
S2

H￥UIIZ
(2)S1S2 (

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a
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[333]
m4:518.3.1m
(1) S1 7
S2

N
Híè?
ro
UI = 0:9U = 0:9￡ 28:2p2 V = 0:9￡20V = 18V
IR = UI?UoR = 18?61:2￡103A = 10￡10?3A = 10mA
Io = UoR
L
= 62￡103A = 3￡10?3A = 3mA
IZ = IR?Io = (10?3)mA = 7mA
6
(2) S1S2 (

N
H{è?
ro
UI = 1:2U = 1:2￡20V = 24V
IR = UI?UoR
L
= 24?61:2￡103A = 15￡10?3A = 15mA
Io = 3mA
IZ = IR?Io = (15?3)mA = 12mA
?R = 0
yUI = 24V

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R = 0
è
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Uo = 0:7V
r??
{6V￥1pb
18.3.4
è
^???m18.3.3
UbX?UZ = 6V
R1 = 2k?
R2 = 1k?
R3 =
2k?
U1 = 30V
T￥è
@bv"
fl = 50b
kp
(1)èa
{S?
(2)?UO =
15V
RL = 150?
H
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bv￥
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@b
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(1)pèa
{S?
èê9R1??K

UOmin = UZ = 6V
èê9R1??K/
UOmax = R1 +R2R
2
UZ = 2+11 ￡6V = 18V
#Uo￥
{S?16? 18Vb
(2)pT￥5{
bv￥
{è
@
??RL1R1
R2
R3?l￥
#
IC … Io … UoR
L
= 15150A = 0:1A = 100mA
T￥5{1
PC = UCEIC = (30?15)￡0:1W = 1:5W

bv￥
{è
@1
IB = ICfl = 10050 mA = 2mA
18.3.6
m5?

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èê

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7u+ … u?
#m?UXX = 5Vb
7
m5:518.3.6m
UOmin = R1 +Rp +R2R
1 +Rp
UXX = 3:3+5:1+3:35:1+3:3 ￡5V = 6:96V
UOmax = R1 +RP +R2R
1
UXX = 3:3+5:1+3:33:3 ￡5V = 17:73V
8
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