Technical Details

Micro Hydro Power:

Low Water Head:

The series of LH get ready mini axle -flow hydroelectric generator.The model and parameter are as follows:

Low Water Head
Model

Water head(m)

Flow (m3/s)

Power(KW)

Speed(r/min)

pipe diameter( mm)

ZD1.8-0.3DCT4-Z

1.8

0.04

0.30

1500

ZD2.0-0.5DCT4-Z

2

0.045

0.50

1500

ZD2.2-0.7DCT4-Z

2.2

0.05

0.70

1500

ZD2.5-1.0DCT4-Z

2.5

0.05

1.00

1500

 

 

 

 


The form of Micro Hydropower System of mini axle-flow generator: flume, former pool,valve,trash fence, water pipe,generator and outlet of water, etc.


The Structure: It is formed of axle-flow turbine,a rare earth generator of permanent magnetism and an electricity regulator of balance load . (sketch 2)The axle-flow turbine is formed of a water awl (3) ,?eddy shell (4), sealing parts (5), a runner (6) and a tail pipe . The structure of stator is round(1).The runner is made with rare earth magnetism . The electricity regulator of balance load is formed?of electronic controller and electrothermal pipe (2).

The working principle of an electricity regulator of balance load likes sketch 3.The electronic controler can change silicon switch according to voltage change. It can control the current of false load. When load changes ,It may make generator load relatively steady , realizes automatic stabilized voltage and steady frequency function.

Medium Water Head.

Medium Water Head
model

Head

Flow

Output

Speed

Pipe

(m)

(m3/s)

(kW)

(r/min)

(mm)

GD-LZ-20-3KW

4

0.136

3

1000

250

GD-LZ-20-5KW

6

0.151

5

1500

300

GD-LZ-20-6KW

7

0.156

6

1500

300

GD-LZ-20-8KW

9

0.161

8

1500

300

GD-WZ-20-10KW

11

0.165

10

1500

300

GD-LZ-12-3.0KW

11

0.045

3

1500

150

 

 

 

 

 

 

     
1. Overview

This tubular turbine generator unit is applicable to the low-head power station which has a head of less than 20m and the diameter of runner is less than 3m. With the merits of considerable and well-going flow, and high efficiency, this unit is perfectly suitable for developing water resources of low head and large flow in the areas of plains, hills and Coastal place.

2. Structural characteristics:

The feature of this tubular turbine generator unit is that, the turbine is installed in a “s” type flow pipe, and the axis of turbine pierce through the pipe wall then connect with the generator installed outside the pipe. Between the turbine and generator there can be easily installed a accelerator to make the turbine’s speed out of the constraint on the synchronous speed. The guide vanes and runner have the same characteristics as that of the bulb tubular turbine. Its overall layout is diverse and is up to the unit’s size, capacity and the specific circumstances of hydropower stations. For example, generators can be installed in the upstream side of turbine (front axle stretch), and also can be installed in the downstream side (rear axle stretch); Unit’s axis can be level (level axle stretch) or tilted (tilted axle stretch); Flow Road “S” curve can be both vertical and level, it may also be tilted. The most representative of them is the level rear axle stretch form (generators horizontally installed above the draft tube downstream-side of the turbine). This unit has several merits: can be used for large-scale units, the total flow road is shorter than the front axle stretch style, generator has a high installation elevation, and operating and maintaining are convenient. The drawback: draft tube flow bend a lot, partial loss of the hydropower has some influence on efficiency of the unit; Runner installed with a higher elevation so that there is a constraint on the air performance and the crew of flow; Layout for generators, sufficient distance is necessary between the axis and the top of the draft tube.

3. Performance features:

High specific speed, largest flow and high efficiency, low investment and so on. Compared with the traditional vertical axial units, it has simple structure and larger volume of cross flow, less construction works is needed of and the maintaining is easy as well. With the same capacity, tubular turbine unit has a runner of which the diameter is smaller than the axial tubular unit by 10%-15%, the annual generating capacity is larger by 10% -15%, and the investment costs can be saved than axial of about 20%, its economic benefits is significant.

High Water Head:

This kind of Micro-hydro Generator is consisted of an inclined impulse turbine and a set of direct connected AC single-phase / three-phase generator. With the characteristics of small body, lightweight, simple structure, reliable operation and convenient assembly, and serving as the power source of lighting, TVs and recorders, it is most suitable for the households in mountain areas with scattered and small hydroelectric sources. The consumers can do easily themselves the installation and operation. This product has been thoroughly strengthened in the special technical measures to good quality, stable function and easy operation for women and children. Much less investment may add more happiness to your family.

High water head model

Head

Flow

Out put Power

Rotational Speed

Pipe

(m)

(m3/s)

(kW)

(r/min)

(mm)

XJ14-0.3DCT4-Z

12-14

0.003-0.005

0.3

1500

50

XJ18-0.5DCT4-Z

12-18

0.005-0.007

0.5

1500

50-70

XJ18-0.75DCT4-Z

14-18

0.005-0.008

0.75

1500

75

XJ22-1.1DCT4-Z

16-22

0.008-0.010

1.1

1500

100

XJ22-1.1DCTH4-Z

15

0.010-0.015

1.1

1500

125-150

XJ25-1.5DCT4-Z

18-25

0.008-0.011

1.5

1500

125

XJ25-1.5DCTH4-Z

15

0.012-0.018

1.5

1500

125-150

XJ25-3.0DCT4-Z

25-35

0.015-0.019

3.0

1500

125-150

XJ25-3.0DCTF4-Z

18-20

0.018-0.030

3.0

1500

150

XJ28-6.0DCT4/6-Z

28-35

0.030-0.038

6.0

1500

150-200

XJ28-6.0DCTF4/6-Z

18-20

0.038-0.050

6.0

1000

200

XJ30-10DCT4-Z

30-38

0.040-0.050

10

1500

200-250

XJ30-10DCTF4/6-Z

25-30

0.050-0.060

10

1000

200-250

XJ30-12SCTF4-Z

28-35

0.050-0.060

12

1500

200-250

XJ30-15SCTF4/6-Z

30-40

0.060-0.070

15

1500/1000

200

XJ30-20SCTF4/6-Z

30-45

0.060-0.100

20

1500/1000

250-300

XJ38-30SCTF4/6-Z

38-45

0.090-0.120

30

1500/1000

250-300

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The typical micro hydro generator station is as follows (figure 1),which consists of earthwork(inlet conduit construction,unit room and drain etc),the micro hydro generator,electrical wires and the users wires.

The typical micro hydro generator station is as follows (figure 1),which consists of earthwork(inlet conduit construction,unit room and drain etc),the micro hydro generator,electrical wires and the users wires.

01

Penstock

06

Inlet Pipe

11

User

02

Reservoir

07

Tailrace

h

Water head

03

Trash rack

08

Power house

h1

Penstock fall

04

Fore bay

09

Electric pole

h2

Flood altitude

05

Brook

10

Wire

H

Reach fall

The work process is as follows:Collecting the water of stream by reservior,the water inflow the pressure poor through the inlet conduit,the go into th micro hydro generator which is installed in the unit room through the inlet pipeline,force the runner to circumgyate,which drives the genertator to generate electricity.At eh same time,the adjustment machine autoadjust the voltage and the frequency to meet the requirements for power supply,and then the user can use the electricity transmitted hyelectrical wires.

Operation Method:

1) Firstly, check whether all components are completed and the intake of penstock is blocked.

2) Then check whether the runner of turbine can be easily rotated, and rotated in by hand to ensure the voltage meter has readings (put the output switch in OFF position).

3) For the first starting, the output switch should be put in the voltage-stabilized control position (A), then open the gate to let water out from small to large, observe the readings meter till 230V (380V) or so continue enhancing water volume, the voltage device is reliable if the reading keep still. At this time the load can be connected, then adjust the water volume to hold the output of 230V (380V) or so. Once the stabilizing device break down, put the switch in B, then the voltage of unit will be under manual-controlled, you may follow the next procedure to control by valve.

4) During the operation, the load should be kept stable as possible as can be. Don’t shut off the load suddenly, or else the high voltage will burn out the rest load, if you must is connect the load, you may decrease water to small volume at first, then disconnect the most part of load when the voltage has dropped to below 380v (you must do as this even you run the unit under the using of voltage-stabilizing device).

5) It need only close the valve to switch off the unit when the load has been stable after first operation, the power switch may hold on so that you may adjust voltage up to 230V (380V)? directly for next running.

Maintenance:

1) To check and clean the mud and foreign material blocking in the intake house and trash rack.

2) The frame of unit should be injected water-proof grease by using grease cup in every three month, each time rotating for three times. The upper bearing also should be added waterproof grease for every six months.

3) The generator must be conducted the dry treatment before next start if it became wet.

In order to provide optimal performance over a wide range, eight (8) different fixed guide vane angles are available. Runners are available with either four (4) blades. The runner blade angles have been set at the best degree. Induction generator is designed for submersible applications.

The turbine and generator are integrated into a single unit ready to be lowered down into simple compact structures. In a hydro turbine generator all components in the unit are designed to function together from the beginning. There are no transmission shafts to align when installing. Draft tubes, seats are prefabricated steel units, ready to be cast into the structure. While running, the generator is cooled by water flowing around it.

The construction is simple and fast; in most cases old structures can be adapted for use with small changes. The hydro turbine generator is not bolted into the structure. It is simply lowered down to a bottom seat for installation and it can be easily hoisted up for inspection and service.??? The submersible concept dramatically minimizes the impact on the environment, especially on the landscape, because most of the structure is placed either in the waterway or underground. In some applications the whole station is hidden, by being placed below the water surface. No more dominating power houses. But don’t pull down old beautiful mills or stations, put the submersibles under them and use the place in them as a museum or for other activities.

How to measure water head:

Measuring Head

Head is water pressure, created by the difference in elevation between the intake of your pipeline and your water turbine. Head can be measured as vertical distance (feet or meters) or as pressure (pounds per square inch, newtons per square meter, etc.). Regardless of the size of your stream, higher head will produce greater pressure—and therefore higher output—at the turbine.

An altimeter can be useful in estimating head for preliminary site evaluation, but should not be used for the final measurement. It is quite common for low-cost barometric altimeters to reflect errors of 150 feet (46 m) or more, even when calibrated. GPS altimeters are often even less accurate. Topographic maps can also be used to give you a very rough idea of the vertical drop along a section of a stream’s course. But only two methods of head measurement are accurate enough for hydro system design—direct height measurement and water pressure.

Direct Height Measurement

To measure head, you can use a laser level, a surveyor’s transit, a contractor’s level on a tripod, or a sight level (“peashooter”). Direct measurement requires an assistant.

One method is to work downhill using a tall pole with graduated measurements. A measuring tape affixed to a 20-foot (6 m) section of PVC pipe works well. After each measurement, move the transit, or person with the sight level, to where the pole was, and begin again by moving the pole further downhill toward the generator site. Keep each transit or sight level setup exactly level, and make sure that the measuring pole is vertical. Take detailed notes of each measurement and the height of the level. Then, add up the series of measurements and subtract all of the level heights to find total head.

Water Pressure Measurement

If the distance is short enough, you can use one or more garden hoses or lengths of flexible plastic tubing to measure head. This method relies on the constant that each vertical foot of head creates 0.433 psi of water pressure (10 vertical feet creates 4.33 psi). By measuring the pressure at the bottom of the hose, you can calculate the elevation change.

Run the hose (or tubing) from your proposed intake site to your proposed turbine location. If you attach multiple hoses together, make sure that each connection is tight and leak free. Attach an accurate pressure gauge to the bottom end of the hose, and completely fill the hose with water. Make sure that there are no high spots in the hose that could trap air. You can flush water through the hose before the gauge is connected to force out any air bubbles.

If necessary, you can measure total head over longer distances by moving the hose and taking multiple readings. Keep in mind, however, that there is less than 1/2 psi difference for every vertical foot. Except for very steep hillsides, even a 100-foot hose may drop only a few vertical feet. The chance for error significantly increases with a series of low-head readings. Use the longest possible hose, along with a highly accurate pressure gauge.

Computing Net Head

By recording the measurements described in the previous sections, you have determined gross head—the true vertical distance from intake to turbine, and the resulting pressure at the bottom. Net head, on the other hand, is the pressure at the bottom of your pipeline when water is actually flowing to your turbine. This will always be less than the gross head you measured, due to friction losses within the pipeline. You will need to have water flow figures (described in the following sections) to compute net head. Longer pipelines, smaller diameters, and higher flows create greater friction. A properly designed pipeline will yield a net head of 85 to 90 percent of the gross head you measured.

Net head is a far more useful measurement than gross head and, along with design flow, is used to determine hydro system components and electrical output. Here are the basics of determining pipe size and net head, but you should work with your turbine supplier to finalize your pipeline specifications.

Head loss refers to the loss of water power due to friction within the pipeline (also known as the penstock). Although a given pipe diameter may be sufficient to carry all of the design flow, the sides, joints, and bends of the pipe create drag as the water passes by, slowing it down. The effect is the same as lowering the head—less water pressure at the turbine.

Head loss cannot be measured unless the water is flowing. A pressure gauge at the bottom of even the smallest pipe will read full psi when the water is static in the pipe. But as the water flows, the friction within the pipe reduces the velocity of the water coming out the bottom. Greater water flows increase friction further.

Larger pipes create less friction, delivering more power to the turbine. But larger pipelines are also more expensive, so there is invariably a trade-off between head loss and system cost. Size your pipe so that not more than 10 to 15 percent of the gross (total) head is lost as pipeline friction. Higher losses may be acceptable for high-head sites (100 feet plus), but pipeline friction losses should be minimized for most low-head sites.

The length of your pipeline has a major influence on both the cost and efficiency of your system. The measurement is easy,though.Simply run a tape measure between your intake and turbine locations,followingthe route you’ll useyou’re your pipeline.Remember that you want to run the pipeline up out of the creek bed,when possible,to avoid damage during high water.

How to measure water flow:

The second major step in evaluating your site’s hydro potential is measuring the flow of the stream. Stream levels change through the seasons, so it is important to measure flow at various times of the year. If this is not possible, attempt to determine various annual flows by discussing the stream with a neighbor, or finding U.S. Geological Survey flow data for your stream or a nearby larger stream. Also keep in mind that fish, birds, plants, and other living things rely on your stream for survival. Never use all of the stream’s water for your hydro system.

?Flow is typically expressed as volume per second or minute. Common examples are gallons or liters per second(orminute),and cubic feet or cubic meters per second(orminute).Each can be easily converted to another,as follows:

1 cubic foot = 7.481 gallons

1 cubic meter = 35.31 cubic feet

1 cubic meter = 1,000 liters

Three popular methods are used for measuring flow—container, float, and weir. Each will be described in detail below.

Container Fill Method

The container fill method is the most common method for determining flow in micro hydro systems.Find a location along the stream where all the water can be caught in a bucket.If such as pot doesn’t exist,build a temporary dam that forces all of the water to flow through a single outlet.Using a bucket or larger container of a known volume,use a stopwatch to time how long it takes to fill the container. Then divide the container size by the number of seconds.

For example, if your container is a 5-gallon paint bucket and it takes 8 seconds to fill, your flow is 0.625 gallons per second (gps) or 37.5 gallons per minute (gpm).

 

Float Method

The float method is useful for large streams if you can locate a section about 10 feet (3 m) long where the stream is fairly consistent in width and depth.

Step1.Measure the average depth of the stream. Select a board able to span the width of the stream and mark it at 1-foot(0.3m) intervals. Lay the board across the stream, and measure the stream depth a teach 1-foot interval. To compute the average depth, add all of your measurements together and divide by the number of measurements you made.

Step2.Compute the area of the cross-section ou just measured by multiplying the average depth you just computed by the width of the stream. For example, a 6-foot-wide stream with an average depth of 1.5 feet would yield a cross-sectional area of 9 square feet.

Step 3.Measure the speed. A good way to measure speed is to mark off a 10-foot (3 m) length of the stream that includes the point where you measured the cross-section. Remember, you only want to know the speed of the water where you measured the cross-section, so the shorter the length of stream you measure, the better.

Use a weighted float that can be clearly seen—an orange or grapefruit works well. Place it well upstream of your measurement area, and use a stopwatch to time how long it takes to travel the length of your measurement section. The stream speed probably varies across its width, so record the times for various locations and average them.

Weir Method

A weir is perhaps the most accurate way to measure small- and medium-sized streams. All the water is directed through an area that is exactly rectangular, making it very easy to measure the height and width of the water to compute flow.

This kind of weir is a temporary dam with a rectangular slot, or gate. The bottom of the gate should be exactly level, and the width of the gate should allow all the water to pass through without spilling over the top of the dam. A narrower gate will increase the depth of the water as it passes through, making it easier to measure.The depth measurement is not taken at the gate itself because the water depth distorts as it moves through the gate. Instead, insert a stake well upstream of the weir gate and make the top of the stake exactly level with the bottom of the weir gate. Measure the depth of the water from the top of the stake.

Once the width and depth of the water are known, a weir table is used to compute the flow. The weir table shown here is based on a gate that is 1 inch (25 mm) wide. Simply multiply the table amount by the width (in inches) of your gate. For example, assume your weir gate is 6 inches wide, and the depth of the water passing over it is 71/2 inches. On the left side of the table, find “7” and move across the row until you find the column for “+1/2”. The table shows 8.21

cfm flow for a 1-inch gate with 71/2 inches of water flowing through it. Since your gate is 6 inches wide, simply multiply the 8.21 by 6 to get 49.26 cfm.

A weir is especially effective for measuring flow during different times of the year. Once the weir is in place, it is easy to quickly measure the depth of the water and chart the flow at various times.