WO2011125072A2

WO2011125072A2 - Water velocity enhancement in canal structure for low head electrical power generation system/turbine

Info

Publication number: WO2011125072A2
Application number: PCT/IN2011/000238
Authority: WO
Inventors: Jayantibhai Prabhuram Patel
Original assignee: Jayantibhai Prabhuram Patel
Priority date: 2010-04-05
Filing date: 2011-04-05
Publication date: 2011-10-13
Also published as: WO2011125072A3; WO2011125072A4

Abstract

The water velocity enhancement in canal structure for velocity based electrical power generation system /turbine mainly comprise of main canal (1), receiving canal (2), head regulator (3) and cross regulator (4),sluice gate (5), hump (6) bucket (7), canal bed level (8), rubble (9) (small stones) or any other suitable material, turbine (10), turbine blades (11), velocity bed (12). Velocity enhancement is achieved by making constructive use of the hump (6) by making velocity bed (12) from the hump level to the height so that the water directly comes across the turbine blades (11).

Description

WATER VELOCITY ENHANCEMENT IN CANAL STRUCTURE FOR LOW HEAD ELECTRICAL POWER GENERATION SYSTEM /TURBINE

FIELD OF THE INVENTION

The present invention relates to a method applied for enhancing the velocity of water for velocity based turbine. More particularly it relates to electric power generating system for river, water stream and canal structure using kinetic energy of flowing water.

BACKGROUND OF THE INVENTION

Hydroelectric power plants convert the hydraulic potential energy from water into electrical energy. Such plants are suitable where water with required head is available.

Hydro-electric power plants capture the energy released by water falling through a vertical distance, and transform this energy into useful electricity using turbines. In general, falling water is channeled through a turbine which converts the water's energy into mechanical power. The rotation of the water turbine is transferred to a generator which produces electricity. The amount of electricity which can be generated at a hydro-electric power plant is dependant upon two factors. The factors are (1) the vertical distance through which the water falls, called the "head", and (2) the flow rate, measured as volume per unit time. The electricity produced is directly proportional to the product of the head and the rate of flow of water. There are mainly three types of hydroelectric installations.

1. Storage facilities.

2. Pumped- storage facilities.

3. Run-of- river.

Storage facilities use a dam to store water in a reservoir. Pumped- storage facilities, have specially designed turbines, where the turbines have the ability to generate electricity in a conventional way when water is delivered through penstocks to the turbines from a reservoir. Run-of-the-river hydroelectricity is a type of hydroelectric generation whereby the natural flow and elevated drop of a river are used to generate electricity.

Turbine selection is mainly based on the available water head rather- than the available flow rate. Generally, impulse turbines are used for high head sites whereas reaction turbines are used for low head sites. "High head" hydro power plants generally utilize a dam to store water for an increased elevation and used for power generation. These high head turbines have comparatively large installation and maintenance cost than low head turbine. Velocity based hydro power plant, of river type, operates under a low elevation of water level and is generally used for irrigation purposes. A low head turbine is used for river and canal structure to generate electricity, wherein the required velocity head of the flowing water is 4- 5meter / sec can be achieved.

There is a large canal network available for irrigation in the worldwide. Canals are man-made channels of water. A canal system receives water from reservoirs or from rivers. It consists of a main canal which distributes water into branch canals. These branch canals are known as receiving canals. In the canal structure, as per the size and capacity of water flow, regulation is done with the mechanism which is called head regulator and cross regulator. Cross regulators (mainly gates) are operated in order to control the water levels, discharges and/ or volumes along this canal. A canal obtains its share of water from the pool behind a barrage through a structure called the canal head regulator. It regulates the discharge and maintains the water levels within a canal network. At this regulation point water velocity and flow rate is controlled by sluice gates installed at these regulators. A sluice gate is traditionally a wooden or metal plate which slides in grooves in the sides of the channel. Sluice gates are commonly used to control water levels and flow rates in rivers and canals. Water falls in to the area called 'Bucket'. This height difference of main canal to receiving canal is called as a Tall height' and the water falling in this area is called as a bucket. Main Canal is also having these kinds of open falls and having buckets also. This works as an energy dissipater and reduces the velocity of water.

Canals with considerable (4- 5 m/s) velocity head can be used for hydro power generation whereas the canals with very low velocity head (1-2 m/s) are used for irrigation and not for hydro power generation. Thus there is a need for enhancing the velocity of the flowing water through the canal to 4-5 m/s from the existing velocity of l-2m/s to make the flowing water of canal useful for power generation by using velocity head turbine.

PRIOR ART AND LIMITATIONS

There are many systems available for electricity generation form the hydro power plant by enhancing the velocity of flowing water through penstock, nozzle etc. The available systems required high installation and maintenance cost and is mainly suitable to the high head turbine

A US Patent no 4,948,985 discloses external penstock which is designed to direct a portion of water from a waterfall to a water wheel coupled to a generator that produces electrical power for industrial and other use. The main limitation with penstock is that velocity enhancement is limited due to the water head loss wherein the water head loss is associated with energy loss per length of pipe.

A run-of-river hydroelectric plant is one in which the output of electricity depends upon the amount of water flowing in the river. United States Patent 4674279 discloses a control system for a hydroelectric power- plant of the run-of-river type wherein the load on the turbine-generator units is matched to the flow of the river so that the units operate at the maximum head available for existing flow conditions to produce the maximum energy available from the river flow for the installed capacity of the plant and- within the allowable, safe operating capability range of the turbine-generator units. Reservoir water level sensors provide a signals indicative of changing water level, sensors for generator electrical and thermal operating characteristics provide a signals related thereto, and a control connected to the water level sensors, to the generator sensors and to the turbine governor adjusts the turbine flow control devices to change the turbine power in response to changing river level within the safe and allowable operating range of the generator. Adjusting the turbine power to match the water available either when the reservoir level increases or decreases maintains maximum head for the power plant to obtain maximum energy there from.

Here, in this patented invention sensors are used from reservoir level to the generator level to meet the fluctuation of the flowing water .The said system required high installation and maintenance cost. If the sensors are not working due to mechanical or climatic disturbance, it will disrupt the whole system. The rate of electricity generation in this case is not constant as it depends on the water level of the reservoir.

Thus there is a clear unmeet need for a system giving constant output, requiring minimal installation and maintenance cost.

OBJECTS OF THE INVENTION

The main object of the present invention is to enhance the velocity of the flowing water passing through the canal structure or river for power generation, with the help of velocity based turbine.

Another object of the present invention is to make constructive use of the hump so as to enhance the velocity of the water by making velocity bed from the hump level to the height so that the water directly comes across the turbine blades.

Further object of the present invention is to create the said velocity bed over the canal bed level by filling rubble or any other suitable material into the buckets for the enhancement of the water velocity.

Further object of the present invention is to improve the RPM of velocity based turbine by reducing the back water effect of water flowing in canal coming out from the turbine blades.

Further object of the present invention is to minimize the friction by applying glossy material on the surface of, the said velocity bed. Further object of the present invention is to provide a system which is suitable for remote and hilly areas where extension of the grid system is comparatively uneconomical.

Further object of the present invention is to provide system which gives more plant load factor as compared to the other method for generating power.

Further object of the present invention is to provide a velocity based turbine system for generating electrical power using flow of water, which is well protected against natural calamities such as storms and floods.

Further object of the present invention is to provide a velocity based turbine system for generating electrical power using flow of water which is durable, economical, and efficient.

Further object of the present invention is to provide as system having inherent ability of instantaneous starting and stopping, load variation and reliability of power.

Further object of the present invention is to provide a velocity based turbine system for generating electrical power using flow of water, wherein the area and capacity of the system can be varied according to the requirements.

SUMMMARY OF THE INNOVATION

The present innovation relates to a velocity enhancement of flowing water through a canal structure, river and water stream etc, which is further used to operate the velocity based turbines. In canal structure, head regulator and cross regulator mechanisms are provided, as per the size and capacity of canal to regulate the flow and level of water passing through the canal. At this regulation point water velocity and flow rate is controlled by the sluice gates installed at these regulators. The height difference of main canal and receiving canal is called as a 'fall height'. Water falls into the area called 'Bucket'. Main Canal also includes these kinds of open falls and buckets which works as an energy dissipater and reduces the velocity of water.

The velocity head of the water flowing through this type of canal is very low (1 - 2 meter/ sec) which is useful for irrigation purpose only. To use the water with low velocity head (1-2 meter /sec) for power generation requires the enhancement of velocity.

The enhancement of velocity head from 1-2 meter/sec to 4-5 meter /sec is obtained by filling the bucket of receiving canal with rubble (small stone) or other suitable material. A velocity bed with or without slope is created by filling the rubble (small stones) or any other material to flow the water at constant rate, with enhanced velocity (4-5 m/s) which directly comes across to the turbine blades, to generate the power at the constant rate.

The enhanced velocity head 4 - 5 meter/ sec of flowing water increases the RPM of turbine to the required RPM. These further decreases the ratio of gear box required for mechanical power transmission. Thus, it efficiently transmits the power to the electrical alternator connected to the other end of gear box. BRIEF DESCRIPTION OF THE INNOVATION

Fig 1 : shows the layout of main canal -Receiving canal.

Fig 2 : schematic diagram of conventional canal structure.

Fig 3 : shows the schematic diagram of the restructured canal. Fig 4 : shows the schematic diagram of the arrangement with velocity based turbine.

Fig 5 : shows the schematic diagram of the velocity bed with glossy material to reduce the friction co-efficient.

As referred to fig 1 there is shown a Main canal (1) which branches into the receiving canals (2). A head regulator (3) and cross regulator (4) is shown which regulates the flow of water passing through the sluice gate (5).

As refereed to fig 2 there is shown a conventional canal structure comprising of sluice gate (5) through which water is passed to the main canal (1) which further flows to the receiving canal (2). The sluice gate is shown which control water levels and flow rates in rivers and canals. A hump (6) is shown which breaks the energy of the flowing water. A bucket (7) is shown in the fig which breaks the velocity of the flowing water. A canal bed level (8) is shown through which water is passed which further passed to the turbine blades (10) to generate power.

As Referred to fig 3, 4, 5 there is shown a flowing Canal with restructuring having the fall height, which can be refereed as "water head" is the difference between main canal (1) and the receiving canal (2). The flowing water falls into the bucket (7) from the main canal (1) .The bucket (7) is the area of the receiving canal (2), collects the falling water from the main canal (1). The rubble (9) (small stones) or any other suitable material that are poured into the bucket (7) as to increase the velocity head. Generally a hump (6) is provided in the canal structure to break the energy of the flowing water. Here, velocity is reduced through the bucket (7) (as shown in fig 1) whereas in the present innovation, the restructuring of the hump (6) is done so as to enhance the said velocity of the water. A velocity bed (12) is provided by maintaining the level of the hump (6) by filling the bucket (7) with rubble (small stones) or any other suitable material. So the flowing water is comes across to the turbine blades (1 1) which increase the RPM of the turbine (10). To achieve the same, the hump level is extended to the height such that the water comes across to the turbine blades, which gives an increased water velocity as 4-5 m/s. The said hump level is a velocity bed (12) from the hump line to the height such that the water directly comes across the turbine blades .Here, the rubble (9) (small stones) or any other suitable material are used to maintain the level of the hump (6) till the height such that the water directly comes across the turbine blades (11). A velocity bed (12) is provided to flow the water at constant rate.The surface of the velocity bed (12) is furnished with glossy material to minimize friction.

A new additional bucket can be provided in the forward direction of the velocity based turbine to decrease the velocity of water flowing out from the velocity based turbine to protect the canal structure.

The velocity head is increased by various forms such as; by increasing the gradient of canal, by increasing the height of free board walls and by building new humps of height in the range of 1 -3 meter. Increased power generation is obtained by placing plurality of turbine unit to the flowing water. WORKING OF THE INNOVATION

In the present system, the water flows vertically from the main canal (1) and comes across the bucket (7) wherein the said bucket (7) is filled with small stones (rubble) or any other suitable material .The said rubble (9) (small stones) or any other suitable material are pored into the bucket (7) making a velocity bad (12) to comes across the flowing water to the turbine blades (1 1) to increase the RPM of the said turbine blades (1 1). Here the velocity bed (12) is created by using rubble (9) (small stones) or any other suitable material which maintains the level of the hump (6) till the height such that the water directly comes across the turbine blades (1 1). The velocity bed (12) is provided by maintaining the level of the hump (6) by filling the bucket (7) with rubble or any other suitable material .Here, velocity is enhanced by making the velocity bed (12) of the poured material by coming across the water with constant flow rate and with enhanced velocity to the turbine blades (11). The enhanced velocity of the water will increase the RPM of turbine (10). This increased RPM will decrease the ratio of gear box required for mechanical transmission. The alternator attached to the other end of the gear box helps in generating the electricity.

Claims

1. The water velocity enhancement in canal structure for velocity based electrical power generation system /turbine mainly comprise of main canal (1), receiving canal (2), head regulator (3) and cross regulator (4), sluice gate (5), hump (6) bucket (7), canal bed level (8), rubble (9) (small stones) or any other suitable material, turbine ( 10), turbine blades(l 1), velocity bed( 12).

2. The water velocity enhancement in canal structure for velocity based electrical power generation system /turbine as claimed in claim 1 wherein the said bucket (7) is filled with rubble (9) (small stones) or any other suitable material.

3. The water velocity enhancement in canal structure for velocity based electrical power generation system /turbine as claimed in claim 1 wherein the water velocity of flowing water is enhanced from 1-2 m/s to 4-5m/s.

4. The water velocity enhancement in canal structure for velocity based electrical power generation system /turbine as claimed in claim 1 wherein the said rubble (9) (small stones) or any other suitable material makes a velocity bed ( 12) to comes across the turbine blades ( 1 1) directly.

5. The water velocity enhancement in canal structure for velocity based electrical power generation system /turbine as claimed in claims 1 85 4 wherein the velocity bed ( 12) is created form hump level to the height such that the water directly comes across the turbine blades ( 1 1) .

6. The water velocity enhancement in canal structure for velocity based electrical power generation system /turbine as claimed in claims 1,4 & 5 wherein the velocity bed (12) is furnished by glossy material.

7. The water velocity enhancement in canal structure for velocity based electrical power generation system /turbine as claimed in claims 1, 4, 5 & 6 wherein the water flows at constant rate through the said velocity bed (12) gives constant power output.

8. The water velocity enhancement in canal structure for velocity based electrical power generation system /turbine as claimed in claim 1 wherein the said system has the ability of instantaneous starting and stopping, load variation and reliability of power.