Micro hydro électricité - ac-rouen.frneruda-lyc.spip.ac-rouen.fr/IMG/pdf/micro_hydro_complet_setubal.pdf · Regulation, control and protection Long pipes: water hammer! golpe de

Micro hydro-electricity

Joint teaching

IPS – Lycée Pablo Neruda

Pr. Pierre-Louis Corrieu

DIEPPE

Techniciens supérieurs

•Electrotechnique

•Environnement nucléaire

•Systèmes automatiques

•Microtechniques


3

World (continents) :

Average altitude : 840 m Energy = Mass x Gravity x Height

Surface : 150.106 km² 1kWh = 3.6 x 106 Joules

Average flow : 814 mm / year

Energy : 285 000 TWh per year (285. 1015 Wh / year)

Theoretical power : 33000 GW

Electricity in France

530 TWh / year

Hydropower : 70 TWh / year

Electricity in Portugal

48.2 TWh / year

Hydropower : 16.4 TWh / year

World : 19800 GW, hydropower 4200 TWh / year

1 – Ressources

Hydro electricity

Production

4

Portugal 92,200 km²

Installed hydropower capacity (2014):

4,455 MW + 1,343 MW pumped storage

Hydropower generation: 16.4 TWh

1 – Ressources

Micro hydro electricity

Potential of hydroelectric development in France

5

Micro hydroelectricity

2300 MW installed

+ 20 MW each year

1 – Ressources

A large house: 15000 kWh / year


Ex1: Quasi constant - River Durdent : 3,8 m3/s 25 km

Altitude : 50 m

Theoretical net potential:

1900 kW

16 GWh / year

1 – Ressources

Rio Paranà : 16 000 m3/s

Seine : 500 m3/s

Nil : 2800 m3/s

Yang Tse : 30 000 m3/s ; 85 TWh/an

6River Béthune : 2,9 m

3/s

Tidal stream generators

7


1 – Ressources


Micro production plant

8

Inlet

Dam

Diversion

canalPlant

building

Outlet canal

Fish-way

Minimum

instream flow

2 – Transforming hydro-power


9

Cost of a micro-plant

5 000 to 12 000 € per kW.

Operation cost is low Availability is high

Numerous examples throughout the world :

China, Kenya, Vietnam…


Simple solution #1: use the speed of the flow



10

Tarn, southern France :

traditional mill

Efficiency :

20 to 40%

Morocco, traditional mill

Simple solution #2: use the weight of water

11

Central France

(Combrailles):

a traditional mill



Vertical or horizontal?

12

50 à 100 rpm

3 à 5 HP

10 à 15 rpm

5 à 10 HP

Horizontal axis Vertical wheel

Vertical axis Horizontal wheel



Fluid energetics

13

Navier-Stokes’ Equation

Newtonian incompressible viscous fluid

Euler’s equation

Perfect flow

Incompressible non-viscous fluid

Bernoulli’s Equation

Stationary perfect irrotational flow

Incompressible non-viscous fluid

Uniform gravitational field



Power computation: Bernoulli’s Equation

14

Pressure

Pressure

Velocity

Velocity

Height



Power : Bernoulli’s Equation

15

Power

Mass flow

Volumic mass

Pressure

Gravity

Net head

Input and

output

velocities

External work

(per 1 kg)



Power: Bernoulli’s Equation

16

kg.s-1.N.m-2 / (kg.m -3) = N . m.s-1

kg.s-1. m.s-2.m= N . m.s-1 ; ( N=kg.m.s-2 )

kg.s-1. (m.s-1)2= J.s-1 ; ( J=kg.m2.s-2 )

Power of pressure forces

Power of lifting (gravity) forces

Variation in kinetic energy



17

Quantities in a small power station

Water inlet

Penstock

Pressure

Kinetic

energyLoad losses

Total

head

Net

head

1 bar

1 barFlow &

Velocity

Turbine

Water

outlet



Overshot waterwheel

18



Efficiency: 60 à 70%

Needs a

‘high’ head

Undershot waterwheels

19

Egressing water impedes the motion

Low heads, doesn’t need a reservoir

Great industrial success



Poncelet 1817

Low head

Breastshot waterwheels: Zuppinger 1883

20

Efficiency: up to 80 %



Action (‘impulse’) turbines: Pelton 1879

21Efficiency up to 90%

Kinetic energy on buckets



High head

turbine is not immersed

Action turbines : Ossberger – Banki 1922

(‘Crossflow’)

Low head

Good efficiency at low flow

22



Transverse flow

Water crosses paddles twice

Reaction turbines : immersed operation

Kinetic+pressure – use of a whirl (remoinho)

Euler’s Theorem

V1

V2

qm.(V2 – V1) = W + R

qm= mass flow

W : weight

R : reaction force

R

23



Reaction turbines : Fourneyron 1827

Efficiency: 70 %

24

Low head

Central water ingress



Reaction turbines : Francis 1830

Efficiency: 80 to 90 % , medium / low head

25



Reaction turbines: Kaplan 1912

Efficiency: 90 to 95 %

26

Variable pitch possible

Very low head



http://fr.wikipedia.org/wiki/Fichier:S_vs_kaplan_schnitt_1_zoom.jpg

Tidal stream generators: SABELLA D10

27

Fixed pitch - elliptical profile

12 pole synchronous generator



Nominal stream flow 3.8 m/s

Operating areas: choosing a turbine for micro-hydro in Normandy

Débit m3/s 28

Net head

Volumic flow

Pelton

Francis - Kaplan

Ossberger-Banki

Available ressource

in Normandy



29

Questions ???



3.Producing electricity

30

Gerador de corrente contínua

Gerador síncrono (corrente alternada)

Gerador de indução (Gerador assíncrono)

Rede elétrica

Transformador & Sistema trifásico

Direct current generator

Synchronous generator(alternate current)

Induction generator (Asynchronous generator)

Electric grid

Transformer & 3-phase system

Transmission and transformation of motion

31

4 rpm

1500 rpm



Turbine speed

Generator speed

Electrical frequency

Separate network

32

Turbine power – load power = acceleration power

T = J d/dt = Tturbine

- Tload

Speed Load & hydraulic power

Torque Current + magnetic field Consumption

Load torque

Stabilizing

Destabilizing

Current

Voltage

Heating

Computers



Direct current generators

33

(1) e=k1.. rotational emf

(2) u = e-R.i electric loop rule

(3) = a.u+b.i magnetic flux

(4) T=k2 ..i torque

Compound excitation allows to compensate voltage drop due to

current (resistive drop & armature magnetic reaction)

Máquina (gerador) de corrente contínua

(1) tensão induzida

(2) lei das malhas

(3) campo magnético (excitação composta)

(4) momento de torção



Compound alternator

No-load start :

residual flux +

direction of Jexc +

Rd low

3. 2.d excR J U

Voltage drop

- inductive load

- conduction overlap

34

Increase Jexc if main

current increases :

3

. 2. . .d exc excR J U R m I J

Tensões alternadas trifásicas

Micro hydro-electricity 3.Producing electricity

UR1 UR2

Electronicaly controled excitation alternator

35

Advantages :

- excitation law can be controled

- machine can be de-excited



Rectifier or chopper

36

Internal or external rotors

Used in lifts



2elec mech

pf f

Slow-shaft machines(gearless or reduced gearing)

37

Enercon E82

Used in wind turbines



Slow shaft - multi-pole

Auto excited asynchronous machine

38

Needs reactive

power

Start-up capacitors

Resonance with stator self-inductance



Self excited

asynchronous

machine:

Starting process

39



Grid-connected

40

T = J d/dt = Tturbine

- Tload

Speed Grid frequency (fixed)

Torque Current + magnetic field Grid demand + control

Micro hydro-electricity 3.Producing electricity

41

Operating point

Load torque



Issues

Starting and coupling: slip 5% ( 10 %)

Speed, torque and frequency measurements

Reactive power compensation

42

M.As

AC

AC

Starter and coupler

Solution adoptée au moulin Sainte Catherine



43

Intermediate direct voltage bus

Total power flows through converter

Good variability of speed [0 to 200%]



44



Pm = Préseau

Préseau = Ps - Pr

Pr = g x Ps

Ps = Préseau / (1-g)

Double fed induction machine DFIM

30% power through converter

Allows larger slip

45

Simplicity, efficiency

Control: input flow only

Motor mode possible

Synchronization to make first

Possible machine-grid resonance

Self-excited



46

Intermediate DC-bus

Total power flows through converter

Good speed-variability [0 to 200%]



Simple control

No de-excitation

47


4. Regulation, control and protection

48

Example: Starting production1. Preparation

Open main valve - Close bypass valve

2. Starting

Slowly open distribution, turbine begins to spin.

3. Set zero operating point on separate network

Get to nominal speed - Stabilize speed (hydraulic distribution)

Stabilize voltage ( adjusting magnetic field – if equipped)

4. Supply consumers & regulate

Close switch to deliver to consumers

Adjust frequency and voltage (separate) / Adjust power (connected)

5. Protect against defects

Insulation – Over-current - Short-circuits - Loss of power

Opening of load circuit or field circuit:

overspeeding!



Long pipes: water hammer! golpe de aríete

49

UPS

For PLC

Backed-up busbar

From public

distribution

From synchronous machine

To user

Compound

synchronous machine



Example : switched sources, moulin Durdent, Mr Tramontin, Cany-Barville

50

UPS backed-

up busbar

To Control system

Valves

Motor busbar



Example : switched sources, moulin Durdent, Mr Tramontin, Cany-Barville (continued)

Electric safety

51

N

PE

RCD 30mA

Classical protection wiring: Internal fault is not detected by

Residual Current Device (RCD)

Dispositivo de Corrente Residual (DCR)



52

Close valves

Solution: zero sequence relay (homopolar) on neutral earthing connection



Shut-down distribution

I_MAX

MS

TN

TT

Micro hydro électricité

Relais homopolaire : relais

53Large gamme de In et t

MERLIN GERIN


Relais homopolaire : relais

54

Micro hydro électricitéRelais homopolaire et surveillance : relais SEPAM

55


Relais homopolaire : relais SEPAM

56


57

Questions ???

58

Horizontal axis Zuppinger wheel (4 rpm)

9 kW - three-phase

Compound synchronous

Separate network

Issues:

Speed regulation

Phase balancing


Example 1 : Moulin Durdent - Cany Barville

M. Tramontin

59

Vertical axis Francis turbine (60 rpm)

30 kW - three-phase

Asynchronous with external starter

Grid connected

Issues:

Starting

Reversibility


Example 2 : Moulin Sainte-Catherine - Oherville

M.Paumelle

60

Vertical axis Francis turbine (30 rpm)

30 kW DC compound

Separate network

Issues:

Voltage regulation

DC machine maintenance (brushes)


Example 3 : Moulin de haut River Yères

Criel sur mer - M.Choquart

61

AgradecimentosPr. Rossana SantosPr. José Luis Sousa

Pr. Paulo FontesSenhora Ferreira


Ex3: O rio Tejo (m3/s)

62

1 – Ressources

Breastshot waterwheels: Sagebien 1858

63

Elementary

Improved



Low head

Documents

Micro hydro électricité - ac-rouen.frneruda-lyc.spip.ac-rouen.fr/IMG/pdf/micro_hydro_complet_setubal.pdf · Regulation, control and protection Long pipes: water hammer! golpe de