电力系统分析课后答案

2-17.某一回110kv 架空电力线路,长度为60km,导线型号LGJ-120,导线计算外径为15.2mm,三相导线水平排列,两相邻导线三相间的距离为4m,试计算该电力线路的参数,并作等效电路。 解: ()km s

r Ω==

=

2625.0120

5

.311ρ

)(6.72

2

.15mm r ==

)

(7.503940002400040003mm D m =⨯⨯⨯=()s r D b km r D X m m 6661110

69.2106.77

.5039lg 58

.710lg

58.7)/(423.00157.06.77

.5039lg 1445.00157.0lg

1445.0---⨯=⨯=⨯=Ω=+=+= .01=g

则 .

0)

(10807.02

)(10

614.16010

69.2)

(38.2560423.0)(75.15602625.014

1

4

6

111111=⨯=⨯=⨯⨯==Ω=⨯==Ω=⨯==---G s B s l b B l x X l r R

.

0)

/(10805.12

16

1

=⨯=-g km s b

2-19.三相双绕组升压变压器的型号为SFL-40500/110,额定容量为40500KVA,额定电压为121/10.5KV,,4.234kw P k =,11(%)=k U ,6.930kw P =

,315.2(%)0=I 求该变压器的参数,并作等值电路。

解: `)(1057.1)

1040500()105.10(104.23422

32332

2

Ω⨯=⨯⨯⨯⨯==

-N

N K T S U P R

)(105.8)

105.10(1001040500315.2100(%))(1049.8)

105.10(106.93)(3.010********)105.10(11100(%)32

332

042

33

2

03

2

32

S U S I B S U P G S U U X N

N T N

T N N N T --⨯=⨯⨯⨯⨯==

⨯=⨯⨯==Ω=⨯⨯⨯⨯==

2-20.三相三绕组降压变压器的型号为

SFPSL-120000/220,额定容量为

120000/120000/60000KVA,额定电压为220/121/11KV,,601)21(KW P K =-

,5.182)31(KW P K =-,

25.28(%),85.14(%),5.132)31()21()32(===---K K K U U KW P ,663.0(%),135,96.7(%)00)32(===-I KW P U K 求该变压器的参数,并作等值电路。

解: I: )(601)21(KW P K =-

)

(5304)(7304)32(')32()31(')31(KW P P KW P P K K K K ====----

)(5.329)(2

1)(5.200)(21)(5.400)(21)21(')32(')31(3

')31(')32()21(2'

)32(')31()21(1KW P P P P KW P P P P KW P P P P K K K K K K K K K K K K =-+==-+==-+=--------- )(107.1)101012()10220(105.329)(674.0)101012()10220(105.200)(346.1)101012()10220(105.4002

342332

2133

2342332

21222342332

2

111Ω=⨯⨯⨯⨯⨯==Ω=⨯⨯⨯⨯⨯==Ω=⨯⨯⨯⨯⨯==N N K T N N K T N N K T S U P R S U P R S U P R II ：96.7(%),25.28(%),85.14(%))32()31()21(===---K K K U U U

)

(076.43101012100)10220(68.10100(%))

(971.10101012100)10220(72.2100(%))

(866.70101012100)10220(57.17100(%)68

.10(%))(%)(%)(2

1

(%)72

.2(%))(%)(%)(21

(%)57.17(%))(%)(%)(21

(%)3

4232133

342321223

42321

11)21()32()31(3)31()32()21(2)32()31()21(1Ω=⨯⨯⨯⨯⨯==Ω-=⨯⨯⨯⨯⨯-==Ω=⨯⨯⨯⨯⨯===-+=-=-+==-+=---------N N K T N N K T N N K T K K K K K K K K K K K K S U U X S U U X S U U X U U U U U U U U U U U U III ：)(1079.2)

10220(101356

2

33210S U P G N T -⨯=⨯⨯== IV ：)(10644.1)

10220(100101012663.0100(%)52

33

4210S U S I B N N T -⨯=⨯⨯⨯⨯⨯== 2-22.双水内冷汽轮同步发电机的型号为TQFS-125-2,,125MW P N =

,18.0,257.0,867.1,8.13,85.0cos '

'=====d d d N N X X X KV U ϕ试计算该发电机的直

轴同步电抗d X ,暂态电抗'd X ,直轴次暂态电抗'

'd X 的有名值.

解: 22

cos 1.295()N N N

N N N

U U Z S P ϕ===Ω

)(418.2295.1867.1867.1Ω=⨯==N d Z X

)

(233.0295.118.018.0)

(333.0295.1257.0257.0'''

Ω=⨯==Ω=⨯==N d

N d Z X Z X

2-23.电抗器型号为NKL-6-500-4,,500,6A I KV U N N ==电抗器电抗百分数.4(%)=L X 试计算该电抗器电抗的有名值. 解: )(277.0500

310010643100(%)3Ω=⨯⨯⨯=

=

N

N L L I U X X