Difference between revisions of "Electrical-Mechanical Equipment"

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== Introduction  ==
 
  
<u>disambiguation</u>:<br>
+
[[Portal:Hydro|► Back to Hydro Portal]]
  
grid connection<br>
+
= Overview =
  
island / isolated grids<br>  
+
-> See article [[Micro Hydro Power (MHP) Plants|Micro Hydro Power (MHP) Plants]]
  
battery storage / charging stations
+
<br/>
  
== Grid connection for mhp's  ==
+
= Turbine Types<br/> =
  
Hydropower usually operates 24 h / day. Most mhp's are connected by a grid to their consumers. If&nbsp;a connection towards the national or main grid is available, electricity can be fed in there. Often micro or pico hydropower units are installed in remote areas. There they feed an isolated grid. In such grid the mhp is usually the only power source. The power produced has to be leveled equal with the power consumed (see controller).<br> Battery storage is no must like at solar or wind power projects. This is a big advantage as it reduces costs and maintenance significantly. Nevertheless can charging stations extend a mhp's effectiveness by utilising power in times of low demand (late night). So even consumers can be served with are to far from the station to be connected by transmission cable.
+
A [[Steffturbine - Hydropower Turbine|turbine]] converts the energy in falling water into shaft power. There are various types of turbine which can be categorized in one of several ways. The choice of turbine will depend mainly on the pressure head available and the design flow for the proposed hydropower installation. As shown in table 2 below, turbines are broadly divided into three groups; high, medium and low head, and into two categories: impulse and reaction.<br/>
  
== Storage basin or dams  ==
+
The difference between impulse and reaction can be explained simply by stating that the impulse turbines convert the kinetic energy of a jet of water in air into movement by striking turbine buckets or blades - there is no pressure reduction as the water pressure is atmospheric on both sides of the impeller. The blades of a reaction turbine, on the other hand, are totally immersed in the flow of water, and the angular as well as linear momentum of the water is converted into shaft power - the pressure of water leaving the runner is reduced to atmospheric or lower.
  
Small hydropower plants usually use (part-) river flow as driving force. Storage basins or even dams can buffer water. So demand peaks or (short) periods of water shortage can be bridged. As such infrastructures is costly and sophisticated, it's only used if there is a clear financial revenue; e.g. electricity supply for remote industries.
+
{| align="right" cellpadding="0" border="1" style="width: 100%"
 +
|-
 +
| style="vertical-align: top" rowspan="2" |
 +
'''<span>Turbine</span>'''<br/>
  
== Ballast or dump load  ==
+
'''Runner'''
  
<!--{12766841534926}--><span>A ballast load is mostly an electrical resistance heater. It's sized to handle the
+
| style="text-align: center;  vertical-align: top" colspan="3" |
</span>full generating capacity of the microhydro turbine. They're placed in air or water. If there is more electricity produced then consumed the charge controller uses this excess energy to generate heat.<br>
+
'''<span>Head</span>'''
  
Other but not common ballast load may be pumping water or ice production.
+
'''pressure'''
  
== '''Metering''' ==
+
|-
 +
| style="text-align: center;  vertical-align: top" |
 +
'''High'''
  
<span>AKA:
+
| style="text-align: center;  vertical-align: top" |
battery monitor, amp-hour meter, watt-hour meter</span>
+
'''Medium'''
  
<!--{12766841534929}-->[[Image:|Metering]]
+
| style="text-align: center;  vertical-align: top" |  
 +
'''Low'''<br/>
  
<span>System
+
|-
meters measure and display several different aspects of your
+
| style="vertical-align: top" |
microhydro-electric system´s performance and status—tracking how full
+
Impulse
your
 
battery bank is, how much electricity your turbine is producing or has
 
produced, and how much electricity is being used. Operating your system
 
without
 
metering is like running your car without any gauges—although possible
 
to do,
 
it´s always better to know how well the car is operating and how much
 
fuel is
 
in the tank.</span>
 
  
&nbsp;
+
| style="vertical-align: top" |
 +
*<span>Pelton</span><br/>
 +
*Turgo
 +
*Multi-jet Pelton<br/>
  
[[|]]'''<span>Main DC</span>''' Disconnect
+
| style="vertical-align: top" |
 +
*<span>Crossflow</span><br/>
 +
*Turgo
 +
*Multi-jet Pelton<br/>
  
== '''AKA: Battery/Inverter disconnect'''  ==
+
| style="vertical-align: top" |
 +
*Crossflow<br/>
  
<!--{127668415349210}-->[[Image:|Main DC Disconnect]]
+
|-
 +
| style="vertical-align: top" |  
 +
Reaction
  
<span>In
+
| style="vertical-align: top" |
battery-based systems, a disconnect between the batteries and inverter
+
*<span>Francis</span><br/>
is
+
*Pump-as-turbine (PAT)<br/>
required. This disconnect is typically a large, DC-rated breaker mounted&nbsp;
 
</span>in a sheet-metal enclosure. It allows the inverter to be disconnected from the batteries for service, and protects the inverter-to-battery wiring against electrical faults.<br>
 
  
== '''Inverter'''  ==
+
| style="vertical-align: top" |
 +
*<span>Propeller</span><br/>
 +
*Kaplan<br/>
  
<span>AKA: DC-to-AC
+
| style="vertical-align: top" |
converter </span>  
+
<br/>
  
<!--{127668415349211}-->[[Image:|Battery-Based Inverter]]<span>Inverters
+
|}
transform
 
</span>
 
 
 
the DC electricity stored in your battery bank into AC electricity
 
 
 
for powering household appliances. Grid-tied inverters synchronize the system´s output with the utility´s AC electricity, allowing the system to feed hydro-electricity to the utility grid. Battery-based inverters for off-grid or grid-tied systems often include a battery charger, which is capable of charging a battery bank from either the grid or a backup generator if your creek isn´t flowing or your system is down for maintenance.
 
  
<span>In rare
+
<br/>
cases, an inverter and battery bank are used with larger, off-grid
 
AC-direct
 
systems to increase power availability. The inverter uses the AC to
 
charge the
 
batteries, and synchronizes with the hydro-electric AC supply to
 
supplement it
 
when demand is greater than the output of the hydro generator.</span>  
 
  
[[|]]'''<span>AC</span>''' Breaker Panel
+
<br/>
  
AKA: mains panel, breaker box, service entrance
+
<br/>
  
<!--{127668415349212}-->[[Image:|AC Breaker Panel]]  
+
<br/>
 +
*For further information, click [[Steffturbine - Hydropower Turbine|here]].<br/>
 +
*For information on Pump-as-Turbine, click [[:File:Pump as Turbine (PaT) Manual.doc|here]].
  
<span>The AC
+
<br/>
breaker panel, or mains panel, is the point at which all of a home´s
 
electrical
 
wiring meets with the provider of the electricity, whether that´s the
 
grid or a
 
microhydro-electric system. This wall-mounted panel or box is usually
 
installed
 
in a utility room, basement, garage, or on the exterior of a building.
 
It
 
contains a number of labeled circuit breakers that route electricity to
 
the various
 
rooms throughout a house. These breakers allow electricity to be
 
disconnected
 
for servicing, and also protect the building´s wiring against electrical fires</span>s. <br>
 
  
<span>Just like
+
[[Electrical-Mechanical Equipment#toc|►Go to Top]]
the electrical circuits in your home or office, a grid-tied inverter´s
 
electrical output needs to be routed through an AC circuit breaker. This
 
breaker is usually mounted inside the building´s mains panel. It enables </span>the inverter to be disconnected from either the grid or from electrical loads if servicing is necessary. The breaker also safeguards the circuit´s electrical wiring.'''&nbsp;'''
 
  
'''Kilowatt-Hour Meter'''
+
= Generators =
  
<span>AKA: KWH
+
*[[Thermo Electric Generators|Thermo Electric Generators]]<br/>
meter, utility meter</span>  
 
  
<!--{127668415349213}-->[[Image:|Kilowatt-Hour Meter]]
+
<br/>
  
<span>Most
+
== Established Producers of Hydro Generators ==
homes with grid-tied microhydro-electric systems will have AC
 
electricity both
 
coming from and going to the utility grid. A multichannel KWH meter
 
keeps track
 
of how much grid electricity you´re using and how much your RE system is
 
producing. The utility company often provides intertie-capable meters at no costs</span>'''&nbsp;<br>'''
 
  
'''&nbsp;'''
+
Marelli
  
== ''''Turbines'types'''  ==
+
== Induction Motor as Generator ==
  
<span><!--{127668415349214}-->[[Image:]]</span>  
+
= Controller - Function Principles<br/> =
  
<span>A turbine converts the energy in
+
[[File:Mhp-scheme.jpg|thumb|center|605px|Elements of a Micro Hydro Power Scheme|alt=Elements of a Micro Hydro  Power Scheme]]<br/>
falling water into shaft power. There are various types of turbine which
 
</span>  
 
  
can be
+
A Load- or Flow- controller ensures that the '''power output does not exceed the power demand''' and power output is stable (e.g. 230V, 50 Hz).
  
categorised in one of several ways. The choice of turbine will depend mainly on the pressure head available and the design flow for the proposed hydropower installation. As shown in table 2 below, turbines are broadly divided into three groups; high, medium and low head, and into two categories: impulse and reaction.  
+
Water turbines, like petrol or diesel engines, will '''vary in speed as load is applied''' or relieved. Although not such a great problem with machinery which uses direct shaft power, this speed variation will seriously '''affect frequency and voltage''' output from a generator.
  
{| cellpadding="0" border="1"
+
Traditionally, hydraulic or mechanical speed governors altered flow as the load varied. Nowadays usually electronic load controller (ELC) are used. These prevent speed variations by continuously adding or subtracting an artificial load ('''load controller'''). In that in effect, the turbine is working permanently under full load and the ELC diverts excess energy into a dump load, mostly a heater.&lt;/span&gt; The traditional kind of equalizing power in and output by controlling the flow is usually also automatised ('''flow control'''). Thereby the ELC steers a valve which regulates the amount of water inflowing.
|-
 
| valign="top" rowspan="2" | <br>
 
'''<span>Turbine</span> '''  
 
  
'''Runner'''
+
In case of more power demand than supply the controller cuts off single users (clusters) in order to keep voltage and frequency constant for the others (first and second class connections). Load or flow controller are placed between generator output and the consumer line.<br/>
  
| valign="top" align="center" colspan="3" |
+
[[Electrical-Mechanical Equipment#toc|►Go to Top]]<br/>
'''<span>Head</span> '''
 
  
'''pressure'''
+
== Controller Types ==
  
|-
+
Fluctuating energy demand requires a mechanism which either regulates the water input into the turbine (= flow control) or by diverting excess energy from the consumer connection (= ballast load).
| valign="top" align="center" |
 
'''High'''
 
 
 
| valign="top" align="center" |
 
'''Medium'''
 
 
 
| valign="top" align="center" |
 
'''Low'''<br>
 
 
 
|-
 
| valign="top" |
 
Impulse
 
 
 
| valign="top" |
 
<span>Pelton
 
</span>
 
 
 
Turgo
 
 
 
Multi-jet Pelton <br>
 
 
 
| valign="top" |
 
<span>Crossflow
 
</span>
 
 
 
Turgo
 
 
 
Multi-jet Pelton <br>
 
 
 
| valign="top" |
 
Crossflow
 
 
 
|-
 
| valign="top" |
 
Reaction
 
 
 
| valign="top" |
 
<span>Francis
 
</span>
 
 
 
Pump-as-turbine (PAT) <br>
 
 
 
| valign="top" |
 
<span>Propeller
 
</span>
 
 
 
Kaplan <br>
 
 
 
| valign="top" |
 
&nbsp;
 
 
 
|}
 
  
'''&nbsp;'''
+
For small micro or pico hydropower sites it's sometimes not easy to find the right controller. There is a lower price limit of several 100 USD even for only 1 or 2 kW power. In such cases there may be thought of manual control.
  
<span>The difference between impulse and
+
[[Electrical-Mechanical Equipment#toc|►Go to Top]]
reaction can be explained simply by stating that the ''impulse''
 
turbines
 
convert the kinetic energy of a jet of water in air into movement by
 
striking
 
turbine buckets or blades - there is no pressure reduction as the water
 
pressure is atmospheric on both sides of the impeller. The blades of a ''reaction''
 
turbine, on the other hand, are totally immersed in the flow of water,
 
and the
 
angular as well as linear momentum of the water is converted into shaft
 
power -
 
the pressure of water leaving the runner is reduced to atmospheric or
 
lower. </span>
 
  
== '''Load factor'''  ==
+
=== Load Control ===
  
<span>The load factor is the amount of
+
The electric load controller (ELC) keeps outgoing Voltage and Frequency stable. Therefore the load on the generator has to be kept stable. The controller adds and subtracts an artificial load (heater) in a way to neutralise the fluctuations on the consumer side.
power used divided by the amount of power that is available if the
 
turbine were
 
to be used continuously. Unlike technologies relying on costly fuel
 
sources,
 
the 'fuel' for hydropower generation is free and therefore the plant
 
becomes
 
more cost effective if run for a high percentage of the time. If the  
 
turbine is
 
only used for domestic lighting in the evenings then the plant factor
 
will be
 
very low. If the turbine provides power for rural industry during the
 
day,
 
meets domestic demand during the evening, and maybe pumps water for
 
irrigation
 
in the evening, then the plant factor will be high. </span>
 
  
<span>It is very important to ensure a
+
[[File:Controler.jpg|thumb|right|734px|Controler|alt=Controler.jpg]]
high plant factor if the scheme is to be cost effective and this should
 
be
 
taken into account during the planning stage. Many schemes use a 'dump'
 
load
 
(in conjunction with an electronic load controller - see below), which
 
is
 
effectively a low priority energy demand that can accept surplus energy
 
when an
 
excess is produced e.g. water heating, storage heaters or storage
 
cookers. </span>
 
  
== '''Load control governors'''  ==
+
<br/>
  
<span>Water turbines, like petrol or
+
<br/>
diesel engines, will vary in speed as load is applied or relieved.
 
Although not
 
such a great problem with machinery which uses direct shaft power, this
 
speed
 
variation will seriously affect both frequency and voltage output from a
 
generator. Traditionally, complex hydraulic or mechanical speed
 
governors
 
altered flow as the load varied, but more recently an electronic load
 
controller (ELC) has been developed which has increased the simplicity
 
and
 
reliability of modern micro-hydro sets. The ELC prevents speed
 
variations by
 
continuously adding or subtracting an artificial load, so that in
 
effect, the
 
turbine is working permanently under full load. A further benefit is
 
that the
 
ELC has no moving parts, is very reliable and virtually maintenance
 
free. The
 
advent of electronic load control has allowed the introduction of simple</span> and efficient, multi-jet turbines, no longer burdened by expensive hydraulic governors.&nbsp;
 
  
<br>
+
=== Ballast Load ===
  
== Controller: <br>  ==
+
If energy demand is temporarily low the excess energy is dumped. It's converted into heat by some heat elements either in water or air. To increase an mhp's overall efficiency such excess power could be utilised as well. Therefore some storage technology would be required. Battery charging, freezers, water pumping or heat storage may be options.
  
<!--{12766848790530}--><!--{12766848790531}--> <!--{12766848790532}-->
+
Regarding intelligent load management: [[:File:Operation and Maintenance of Small Hydro.pdf|Operation and Maintenance of Small Hydro]] by Dr Nigel Smith, Dr Philip Taylor and Tim Matthews
  
<span id="1274973221030S" style="display: none;">&nbsp;</span>  
+
<br/>
  
<!--{12766848790533}--><!--{12766848790534}--><!--{12766848790535}--><span lang="DE" style="font-size: 11pt; font-family: Tahoma; color: black;">Function </span><span lang="DE" style="font-size: 11pt; font-family: Tahoma; color: black;">[[Image:Mhp-scheme.jpg|right|560x386px|Elements of a Micro Hydro  Power Scheme]]principles</span><br>
+
=== Flow Control ===
  
Load- or Flow- controller ensure that the power output does not exceed the power demand (e.g. 230V, 50 Hz). <br> If flow of water in a MHP-station is constant the energy output of a turbine/generator is constant as well. Power demand is usually fluctuating over the time (e.g. day/night). If supply is higher than demand, excess energy must be diverted, dumped. alternatively the water flow can be reduced which results in less power output. <br> In case of more power demand than supply the controller cuts of the of demand line. <br> Load controller are placed between generator output and the consumer line.<!--{12766848790536}--> <span lang="DE" style="font-size: 11pt; font-family: Tahoma; color: black;">
+
regulates the amount of water into the turbine in order to match power output and power demand. Nowadays flow control is done mostly via electronics, which steer a valve
</span>
 
  
<br>
+
[[File:Flow-control.jpg|thumb|center|834px|principle flow control|alt=principle flow control]]
  
<br>  
+
<u>Manual Flow Control:</u>
  
<br>
+
In very small schemes often all power for lighting and TV is used constantly. Then energy consumption barely alters or does only at certain times. In such cases it can be even practical to train an operator who open / closes a valve manually to stabilise the Voltage. This allows to disclaim a controller, which saves costs and potentially flaws.
  
<br>  
+
<br/>
  
<!--{12766848790537}--><!--{12766848790538}--> <!--{12766848790539}-->
+
[[Electrical-Mechanical Equipment#toc|►Go to Top]]
  
=== <span lang="DE" style="font-size: 11pt; font-family: Tahoma; color: black;">Controller Types</span>  ===
+
= Load Factor =
  
==== Load controller:  ====
+
The load factor is the amount of power used divided by the amount of power that is available if the turbine were to be used continuously. Unlike technologies relying on costly fuel sources, the 'fuel' for hydropower generation is free and therefore the plant becomes more cost effective if run for a high percentage of the time. If the turbine is only used for domestic lighting in the evenings then the plant factor will be very low. If the turbine provides power for rural industry during the day, meets domestic demand during the evening, and maybe pumps water for irrigation in the evening, then the plant factor will be high.
  
[[Image:Controler.jpg|right|350x141px|Controler.jpg]]
+
It is very important to ensure a high plant factor if the scheme is to be cost effective and this should be taken into account during the planning stage. Many schemes use a 'dump' load (in conjunction with an electronic load controller - see below), which is effectively a low priority energy demand that can accept surplus energy when an excess is produced e.g. water heating, storage heaters or storage cookers.
  
Electronic circuit, which keeps output power constant in Frequency- and Voltage- parameters.
+
[[Electrical-Mechanical Equipment#toc|►Go to Top]]
  
Fluctuating energy demand requires a mechanism which either regulates the water input into the turbine (= flow control) or by diverting excess energy from the consumer connection (= ballast load).
+
= Further Information =
  
==== Ballast load  ====
+
*[[Control Equipment - Hydropower|Control Equipment - Hydropower]]<br/>
 +
*[[Hydropower - Equipment|Hydropower - Equipment]]<br/>
 +
*[[Steffturbine - Hydropower Turbine|Steffturbine - Hydropower Turbine]]
  
usually electrical heaters in water or air. If energy demand is temporarily low the excess energy is converted into heat.
+
<br/>
  
==== Flow control  ====
+
[[Electrical-Mechanical Equipment#toc|►Go to Top]]
  
regulates the amount of water into the turbine in order to match power output and power demand.
+
= References =
  
Nowadays flow control is done mostly via electronics (which steer a valve)  
+
*General:[[Micro Hydro Power (MHP) Manuals|Micro hydro Power Manuals]]
 +
*[[:File:Good and bad of mini hydro power vol.1.pdf|Good and Bad of Mini Hydro Power]]
 +
*[[:File:Hydro scout guide ET may10.pdf|Micro Hydro Power Scout Guide]]
 +
*[http://practicalaction.org/micro-hydro-power-2 Micro-Hydro Power: Practical Action]
  
[[Image:Flow-control.jpg|left|650x264px|principle flow control]]
+
<references /><br/>
  
 
[[Category:Hydro]]
 
[[Category:Hydro]]

Latest revision as of 10:45, 9 September 2014

► Back to Hydro Portal

Overview

-> See article Micro Hydro Power (MHP) Plants


Turbine Types

A turbine converts the energy in falling water into shaft power. There are various types of turbine which can be categorized in one of several ways. The choice of turbine will depend mainly on the pressure head available and the design flow for the proposed hydropower installation. As shown in table 2 below, turbines are broadly divided into three groups; high, medium and low head, and into two categories: impulse and reaction.

The difference between impulse and reaction can be explained simply by stating that the impulse turbines convert the kinetic energy of a jet of water in air into movement by striking turbine buckets or blades - there is no pressure reduction as the water pressure is atmospheric on both sides of the impeller. The blades of a reaction turbine, on the other hand, are totally immersed in the flow of water, and the angular as well as linear momentum of the water is converted into shaft power - the pressure of water leaving the runner is reduced to atmospheric or lower.

Turbine

Runner

Head

pressure

High

Medium

Low

Impulse

  • Pelton
  • Turgo
  • Multi-jet Pelton
  • Crossflow
  • Turgo
  • Multi-jet Pelton
  • Crossflow

Reaction

  • Francis
  • Pump-as-turbine (PAT)
  • Propeller
  • Kaplan






  • For further information, click here.
  • For information on Pump-as-Turbine, click here.


►Go to Top

Generators


Established Producers of Hydro Generators

Marelli

Induction Motor as Generator

Controller - Function Principles

Elements of a Micro Hydro Power Scheme
Elements of a Micro Hydro Power Scheme


A Load- or Flow- controller ensures that the power output does not exceed the power demand and power output is stable (e.g. 230V, 50 Hz).

Water turbines, like petrol or diesel engines, will vary in speed as load is applied or relieved. Although not such a great problem with machinery which uses direct shaft power, this speed variation will seriously affect frequency and voltage output from a generator.

Traditionally, hydraulic or mechanical speed governors altered flow as the load varied. Nowadays usually electronic load controller (ELC) are used. These prevent speed variations by continuously adding or subtracting an artificial load (load controller). In that in effect, the turbine is working permanently under full load and the ELC diverts excess energy into a dump load, mostly a heater.</span> The traditional kind of equalizing power in and output by controlling the flow is usually also automatised (flow control). Thereby the ELC steers a valve which regulates the amount of water inflowing.

In case of more power demand than supply the controller cuts off single users (clusters) in order to keep voltage and frequency constant for the others (first and second class connections). Load or flow controller are placed between generator output and the consumer line.

►Go to Top

Controller Types

Fluctuating energy demand requires a mechanism which either regulates the water input into the turbine (= flow control) or by diverting excess energy from the consumer connection (= ballast load).

For small micro or pico hydropower sites it's sometimes not easy to find the right controller. There is a lower price limit of several 100 USD even for only 1 or 2 kW power. In such cases there may be thought of manual control.

►Go to Top

Load Control

The electric load controller (ELC) keeps outgoing Voltage and Frequency stable. Therefore the load on the generator has to be kept stable. The controller adds and subtracts an artificial load (heater) in a way to neutralise the fluctuations on the consumer side.

Controler.jpg
Controler



Ballast Load

If energy demand is temporarily low the excess energy is dumped. It's converted into heat by some heat elements either in water or air. To increase an mhp's overall efficiency such excess power could be utilised as well. Therefore some storage technology would be required. Battery charging, freezers, water pumping or heat storage may be options.

Regarding intelligent load management: Operation and Maintenance of Small Hydro by Dr Nigel Smith, Dr Philip Taylor and Tim Matthews


Flow Control

regulates the amount of water into the turbine in order to match power output and power demand. Nowadays flow control is done mostly via electronics, which steer a valve

principle flow control
principle flow control

Manual Flow Control:

In very small schemes often all power for lighting and TV is used constantly. Then energy consumption barely alters or does only at certain times. In such cases it can be even practical to train an operator who open / closes a valve manually to stabilise the Voltage. This allows to disclaim a controller, which saves costs and potentially flaws.


►Go to Top

Load Factor

The load factor is the amount of power used divided by the amount of power that is available if the turbine were to be used continuously. Unlike technologies relying on costly fuel sources, the 'fuel' for hydropower generation is free and therefore the plant becomes more cost effective if run for a high percentage of the time. If the turbine is only used for domestic lighting in the evenings then the plant factor will be very low. If the turbine provides power for rural industry during the day, meets domestic demand during the evening, and maybe pumps water for irrigation in the evening, then the plant factor will be high.

It is very important to ensure a high plant factor if the scheme is to be cost effective and this should be taken into account during the planning stage. Many schemes use a 'dump' load (in conjunction with an electronic load controller - see below), which is effectively a low priority energy demand that can accept surplus energy when an excess is produced e.g. water heating, storage heaters or storage cookers.

►Go to Top

Further Information


►Go to Top

References