EXERCISE NUMBER 4 – ELEARNING SUBJECT ELECTROMAGNETIC TRANSIENT PROCESS MISSION CALCULATE, SOFTWARE SIMULATION

VIETNAM GENERAL CONFEDERATION OF LABOUR TON DUC THANG UNIVERSITY FACULTY OF ELECTRICAL & ELECTRONICS ENGINEERING EXERCISE NUMBER 4 – ELEARNING SUBJECT: ELECTROMAGNETIC TRANSIENT PROCESS

VIETNAM GENERAL CONFEDERATION OF LABOUR TON DUC THANG UNIVERSITY FACULTY OF ELECTRICAL &

ELECTRONICS ENGINEERING

EXERCISE NUMBER 4 – ELEARNING

SUBJECT: ELECTROMAGNETIC TRANSIENT PROCESS

MISSION: CALCULATE, SOFTWARE SIMULATION

ADVISED BY: Dr NGUYỄN CÔNG TRÁNG GROUP: 06

NGỌC HOÀNG VŨ, StudentID code: 41900916

NGUYỄN VĂN THẮNG, StudentID code: 41900877 NGUYỄN MINH THUẬN, StudentID code: 41900891 TRANG THANH TUẤN, StudentID code: 41900912

LÊ MINH THẮNG, StudentID code: 41900875

HO CHI MINH CITY, 2021

I Introduce the problem and calculate

The figure:

Generator: S rG1 = 117,5 MVA; U rG1 = 10 KV; Cosφ = 0.85;′′= 0.1593 , 1′′ = 6.6 kV

System: ′′

= 176.5 MVA;

Transformers: SrT1 = SrT2 = 125 MVA; Uđm = 10.5/115 KV; UkT1 % = UkT2 %

= 10.5%;

T3: SrT3= 200 MVA; Uđm = 15.75/242 KV; UkT3% = 11%;

Lines: l1 = 45 km; l2 = 23km; l3= 40km; All 4 lines have X’= 0.4 Ω/km, R’ = 0.3 Ω/km, 110kV

Loads: stuck on busbar 22kV, SrL = 15 MVA, Cosφ = 0.8; ′′ = 0.4

Calculate short circuit:

Choose =10KV

Ta có:

System: = ′′ 176,52 = 102 =0.57

Line 1: 1 = ′ * 1 ∗( ) 2 =0.4*45*( 10 ) 2 =0.15

110

1 = ′ * 1 ∗( ) 2 =0.11

2 = ′ * 2 ∗( ) 2 =0.06

3 = ′ *3 ∗( ) 2 =0.1

Trans1, 2:

1 = 2 = 1 = 2 = 1% * 2 = 10,5

∗102=0.084 100 1 100 125

3 = 3 = 3%*2=11∗102=0.055 100 3 100 200

Loads:

=

2

* Cos( )=

=

2

* Sin( )=

=17,1KV

Generator:

1= + 1=0.14j+0.084j=0.224j

2= 3 + =0.055j+0.57j=0.625j

3 = 3 + =0.084j+5.1+4j=5.3+4.084j

12=

13=

23=

4= 13 + 2=0.04+0.05j+0.625j=0.04+0.675j

5 = 23 + 3 =0.02+0.03j+5.3+4.084j=5.32+4.114j

= + +

1

7

=

∗ 1+ 2∗ 7

7

1,7= 1// 7=5.54*10−3+0.22j

= 1,7 1,7 √(5.54∗10 −3 ) 2 +0.22 2

6 6

3 =

′′

= 3

II Simulate the problem by software.

Introduction about software MELSHORT2.

functions and information about short circuits

difference between two types of CBs is clearly shown through their routing curve diagram

shown very clearly in detail along with other data to make the calculation easier

Simulation

1

Click the icons on the toolbar to create the diagram following the problem.

3. Enter the parameters

○ Generator

○ System

○ Lines

Tick in Calculation point to calculate short circuit at Line 2

4. Click Number 2 to auto check the diagram

The software notification

Click OK then click Number 3 to calculate automatically and show the result.

The result: Isc=22.427kA

Compare

Actual short circuit current

Comment