www.45-eng.com www.vortexhydra.co
m
1
MECHANICAL DESIGN AND OPERATION OF HPP
Ferrara – November 15 2018
www.45-eng.com www.vortexhydra.co
m
2
How the discharge affects the design of HPP?
Turbine type for specific HPP
A simple tool for Hydro Power Plant design
Low head turbines
Francis turbines
Pelton turbines
Scada system
Gates
Example
Lesson program
www.45-eng.com www.vortexhydra.co
m
3
*only on electromechanical equipment
Technical aspects *:
Economic aspects :
Type of turbines Major dimension Efficiency of turbine Energy production
Energy production Cost of equipment Investment profitability
How the discharge affects the design of HPP?
Environments aspects: Maximize the exploitation of the
hydraulic potential of the water resources
www.45-eng.com www.vortexhydra.co
m
4
Design data for a HPP
H: Net head [m] Q: Design discharge [m3/s]
www.45-eng.com www.vortexhydra.co
m
6
!Net head in low head HPP is very important!
H: Head duration curve
www.45-eng.com www.vortexhydra.co
m
8
-N° of turbines? -Type of turbines? -Q design?
Different flow duration curve
www.45-eng.com www.vortexhydra.co
m
9
Total energy in a year
Principal dimension and NPSH
Total cost of equipment
NPV and IRR Tch
nic
al
asp
ects
E
con
om
ic asp
ects
Specific speed
Total earn of HPP
Multiobjective method
www.45-eng.com www.vortexhydra.co
m
16
Technical aspects :
Design data
Type of HPP
Major dimension
Efficiency of turbine
Reliability of HPP
Turbine type for specific HPP
www.45-eng.com www.vortexhydra.co
m
17
Large hydro turbines
Low impact of cost of turbine
High efficiency
Pelton turbine 5 jets
H= 1870m
Q=25mc/s
Dp=3993m
N=428.5 rpm
P=423MW
Andritz Hydro
www.45-eng.com www.vortexhydra.co
m
18
Small hydro turbines
High impact of cost of turbine
Good efficiency
Simple construction
Pelton turbine 4 jets
H= 146m
Q=2mc/s
Dp=0.7m
N=600 rpm
P=2.2MW
Tamanini Hydro
www.45-eng.com www.vortexhydra.co
m
19
Pelton turbine design
Feasibility study
Q , H
Principal dimensions of turbine
Customer needs
Francis - Kaplan turbine design
Feasibility study
Q , H
Principal dimensions of turbine
Costumer need
n n N° Jets
How to choose a turbine
www.45-eng.com www.vortexhydra.co
m
28
• Single regulated
• Double regulated
• Fixed
• Direct-coupled
• Gear box - belt
• PMG e variable speed
Configuration of low head turbines
www.45-eng.com www.vortexhydra.co
m
29
Single regulated
Double regulated
Fixed blade
Low head typical efficiency
0
10
20
30
40
50
60
70
80
90
100
0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6
Efficiency%
Q/Qmax
www.45-eng.com www.vortexhydra.co
m
30
+ - -
Efficiency Operation Capex
Direct-coupled
• Specific speed (Q/H)
• Velocity / n° poles
• Generator capex
www.45-eng.com www.vortexhydra.co
m
31
- + +
Efficiency Operation Capex
Gear box/Belt
-Specific speed(Q/H) -Velocity / n°poles -Generator capex
www.45-eng.com www.vortexhydra.co
m
32
+ - +-
Efficiency Operation Capex
PMG variable speed
-Velocity / n° poles -Generator capex
BP
www.45-eng.com www.vortexhydra.co
m
33
In low head HPP must pay particular attention the design of the intake and the draf tube
The loss of net head is the principal cause of malfunction
www.45-eng.com www.vortexhydra.co
m
36
Francis typical efficiency
Low speed Francis
High speed Francis
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
80.0
90.0
100.0
0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40
Efficiency[%]
Q/Qnom
K<=0.4 K<=0.5 K<=1 K<=1.5 K<=2.0
www.45-eng.com www.vortexhydra.co
m
38
Typical layout
Vertical axis Horizontal axis
6 jets 5 jets
4 jets 3 jets
2 jets
1 jet
www.45-eng.com www.vortexhydra.co
m
39
Pelton typical efficiency
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
80.0
90.0
100.0
0.00 0.20 0.40 0.60 0.80 1.00 1.20
Efficiency[%]
Q/Qmax
Pelton1J Pelton2J Pelton3J Pelton4J Pelton5J Pelton6J
www.45-eng.com www.vortexhydra.co
m
44
RADIAL GATES: Commonly used for Spillway and River Barrage
MACCHERONIS SPILLWAY RADIAL GATE 15X12m
ABU SUKHAIR RIVER BARRAGE RADIAL GATE 12x8m
-SEE FARAHANTSANA PLAN VIEW -SEE VRANDUCK PROJECT RADIAL GATE ASSEMBLY
www.45-eng.com www.vortexhydra.co
m
45
FLAP GATES: Commonly used for River Barrage
SAN PELLEGRINO – FLAP GATE 11,5X2m
www.45-eng.com www.vortexhydra.co
m
46
SLIDING OR FIXED WHEEL GATES: used at water intake
VRANDUK HPP – INTAKE SECTION
www.45-eng.com www.vortexhydra.co
m
47
SLIDING OR FIXED WHEEL GATES: used at dam bottom outlet
RAVEDIS DAM – BOTTOM OUTLET
KARAHNJUKAR DAM BOTTOM OUTLET
www.45-eng.com www.vortexhydra.co
m
48
BUTTERFLY VALVES: tipically used as penstock protection or turbine inlet
LOS NEGROS BUTTERFLY VALVE DN3000 PN6
www.45-eng.com www.vortexhydra.co
m
49
SPHERICAL VALVES: tipically used as turbine inlet valves
MONTEBELLO SPHERICAL VALVES DN700 PN45
www.45-eng.com www.vortexhydra.co
m
53
Caduta idrica disponibile lorda 450m
Caduta idrica disponibile netta a Qmax 436m
www.45-eng.com www.vortexhydra.co
m
54
Numero macchine stabilite 3
Caduta idrica disponibile netta a Qmax 436m
Portata di progetto singola macchina 1300 l/s
www.45-eng.com www.vortexhydra.co
m
55
Q , H
0.5
0.7530 ( )
n Qk
gh
0.96 0.98u
0.88 0.90id
2
idu
u
k
2.1 2u uk iD
d k
10 14D
d
n
i
1 2uc gH
1
4 Qd
i c
2uu k gH
60 uD
n
Flow chart for feasibility study of a Pelton turbine
www.45-eng.com www.vortexhydra.co
m
58
2 Getti orizzontale
np Ngiri Omega Ngetti K Ns C1 d u Dp D/d Z B2 D/B2
[giri/min] 2 [m/s] [mm] [m/s] [mm] [mm]
10 720.0 75.40 2.00 0.16 20.79 90.68 94.05 43.49 1153.6 12.3 21 300.97 3.83
n poli n giri Potenza Peso Gir Forza t 1g Forza t 2g 90° Numero f bocchello Corsa Angolo sp Angolo bocc Spinta molle N molle
[rpm] [kVA] [kN] [kN] [kN] [mm] [mm] [°] [°]
10.00 720.00 0.960 5857.69 18.72 56.12 79.37 2.00 120.39 120.39 50.00 90.00
D/b Rho/B B2 altezza profond. Rho pala Diametro Cassa DN Valvola PN Valvola DN curva 1g DN curva 2g DN curva 3g DN curva 4g DN curva 5g
[mm] [mm] [mm] [mm] [mm] [mm] PN [mm] [mm] [mm] [mm] [mm]
3.83 0.36 301.00 258.65 84.65 108.65 2846.53 731.27 25.00 566.44 400.53 327.04 283.22 253.32
Dati palettatura
Dati generatore
Curva
Iniettori
Valvola
Macchina scelta
www.45-eng.com www.vortexhydra.co
m
59
Vivier, 1966
Nechleba, 1957
B2=(2.6÷3) d0
B2=(2.8÷4) d0
L=(2.25÷2.8) d0
L=(2. 5÷2.8) d0
Pr=(0.8÷1.3) d0
Pr=0.95 d0
B1=(1.2÷1.25) d0
B1=1.2 d0 + 5mm
y=(0.9÷1.2) d0
2 0<3.4B d
Lo Presti, 1922
Rubbo, 1957
B2=(3.5÷4) d0
B2=(3.5÷4) d0
L=(2.45÷2.8) d0
L=(2.5÷3) d0
Pr=(0.9÷1.2) d0
Pr=(0.9÷1.2) d0
Büchi, 1957
Zacchè, 1999
B2=(3.5÷4) d0
B2=(3÷4) d0
L=(0.8÷0.85) B2
D1/B1>2.8
Pr=(0.25÷0.3) B2
De=D1+1.1B2
De=D1+3.5d0
B1=(5÷10)mm+ d0
e=0.056 B2
x=0.4714 B2
2 03.4 <3.8B d