P Pl tPower PlantsA1M15ENY

Lecture No 5Lecture No. 5Jan Špetlík

spetlij@fel cvut cz - subject in e-mail ENY”spetlij@fel.cvut.cz subject in e mail „ENY

Department of Power Engineering Faculty of Eelectrical Engineering CTU Technická 2Department of Power Engineering, Faculty of Eelectrical Engineering CTU, Technická 2, 166 27 Praha 6

Peak short circuit current is:

2 1 7 2 25 59 9 kAi Iκ ′′

73 4 10 3 1l −

3 3. 2. 1,7. 2.25 59,9 kAp ki Iκ= = =Force between main conductors for both cases:

72 2 60

3 33 4. .10 3 1. . . . .59,9 .10 . 1, 242 kN

2. 2 2. 2 0,5m p m

lF id

μ ππ π

= = =

F t

0,73β = . 1rV Vσ = 0,2. 1,5.120 180 MPaqσ = =Factors:

F ff t d t

2 20 010 0 063b1) Vertical arrangement

Force effects on conductors:

31 242 10 1F l

2 25 3. 0,010.0,063 3,97.10 m

6 6a bZ −= = =

33

5

. 1, 242.10 .1. . . 1.0,73. 2,85 MPa8. 8.3,97.10

mm r

F lV VZσ

σ β −= = =

0,2.tot qσ σ

26 30,063.0,010

2) Horizontal arrangement

6 30,063.0,010 1,05.10 m6

Z −= =

33. 1, 242.10 .1F l3

6

. 1, 242.10 .1. . . 1.0,73. 107,9 MPa8. 8.1,05.10

mm r

F lV VZσ

σ β −= = =

C d OK b 0,2.tot qσ σ ⇒

1) Vertical arrangement

1 1α =, 2,7 . 2,72,85 F rtot

V Vσ

= > ⇒ =

2 7 1 1 1 242 7 18 kNF V V Fα= = =

1,1kritα =

3. . . 2,7.1,1.1, 242 7,18 kND F r mF V V Fα= = =

0,025 mT = ,

7,18 0,13 0,025. 10,7 kN P+ = <

Corresponding support is 16 kN

. 10,7 kN0,8 0,13

P<

1,1k itα =0,20,8. 0,8.120 0 889 1 1V V

σ= = < ⇒ =

2) Horizontal arrangement

1,1kritα0,889 1 . 1107,9 F rtot

V Vσ

= = < ⇒ =

3. . . 1.1,1.1, 242 1,37 kND FF V V Fα= = =3. . . 1.1,1.1, 242 1,37 kND F r mF V V Fα

0,052 mT =

1,37 0,13 0,052. 2, 4 kN0,8 0,13

P+ = <

Corresponding support is 5 kN

Rem.

For power outlet from medium sized generator a multiple rigid conductor arrangement can be used (in this case 3 x Al 63x10

h )per phase)

multiple bundled ACSRconductorsconductors

High current resin insulatedconductor system DURESCA

Aluminum enclosed bus ducts are used for the most heavy currentused for the most heavy current demanding installations

GeneratorsIn power generation following types are used:

- Round synchronous machines (two or four poles) for steam turbines up to 1000 MW

- Salient pole synchronous machines (multipole) for hydroelectric power plants power output hundreds of MWpower plants, power output hundreds of MW

- Cage induction machines- Doubly Fed Induction Generators (DFIG), power output tens of

MW for wind farms

Turbogenerators

Hydrogenerators DFIGs

GeneratorsConstruction:

GeneratorsIM code:Mounting arrangementacc. to EN 60034-7acc. to EN 60034 7(generators + motors)

GeneratorsIC code: Cooling arrangement

Cooling arrangement of generators:- Natural cooling - convection- Forced internal cooling (a speed dependent fan located on shaft)

Natural + forced internal cooling (two circuits convection + fan)- Natural + forced internal cooling (two circuits convection + fan)- Forced external cooling (speed independent fan/pump)

GeneratorsIC code: Cooling arrangement

GeneratorsIC code:

GeneratorsClasses of the insulation system:Expresses thermal withstand of (winding) insulation materials, typically:Cl A E tt ilkClass A, E – cotton, silk, paperClass B, F – mica, glass fiber, asbestosClass H – silicone elastomer, porcelain, mica, glass fiberClass H silicone elastomer, porcelain, mica, glass fiber

Rem.:Rem.: Class B / F – most common for 60 Hz / 50 Hz motorsMaterials for special insulation requirements (aerospace, nuclear, physics):Ceramics, silicon resins, teflon, chrome-iron/nickel clad copper (over 200 –600 °C)

Main Parameters SelectionRated apparent power:Dependent of turbine power output + rated power factor (~0,85) Formerly used generator series: 63 MVA / 125 MVA / 235 MVA /Formerly used generator series: 63 MVA / 125 MVA / 235 MVA /588 MVA / 1176 MVA

Rated voltage:Rated voltage:Voltage selection with respect to In, insulation parameters, ability to protect the machine + outer networkpTypical voltage level Vn:

Pn Vndo 50 MW 6 - 6,3 kV

50-100 MW 10,5 - 11 kV

100-200MW 13,8 kV,

200-500 MW 15 - 15,75 kV

1000 MW Temelín 24 kV

Basic Formulas for Steady State

Steady state three phase power:

*ˆ ˆ ˆ3 3 cos 3 sinS P j Q U I U I j U Iϕ ϕ= + = = +. 3. . 3. . .cos .3. . .sinf f fS P j Q U I U I j U Iϕ ϕ= + = = +

2.3 i i 2d qX XU E UP U I β β

−3. . .cos .sin . .sin 2

2 .d q

fd d q

P U IX X X

ϕ β β= = +

2 2X X X XU E U U +2 2.3. . .sin .cos . .cos 2 .2 . 2 .

d q d qf

d d q d q

X X X XU E U UQ U IX X X X X

ϕ β β− +

= = + −

Regulation Fundamentalsg

( ).sys P Wf f s P P= + −Governor: P-f regulation AVR: Q-V regulation

( ).ref Q WV V s Q Q= + −