RS20140491A1 - HYDRO POWER PLANT - Google Patents

Abstract

A hydroelectric power plant for generating electrical power is to be installed in a watercourse of a river without the need of a pondage. The hydroelectric power plant comprises at least two opposing dam walls (1;2),which comprise a shore end (3) arranged at opposing shore sides of the river and a free end (4) extending towards the watercourse of the river with a water passage (5) in between the free ends (4) of two opposing dam walls (1; 2). Further at least one machine unit (6) is provided on one of the at least two opposing dam walls (1; 2), which comprises at least a generator unit for generating electrical power, and a control system for controlling operational parameters of the power plant. At least one moveable dam element (7) is arranged in or nearby the water passage (5), which comprises a lower end (8) that is arranged on the river ground and an upper end (9) that is moveable in height in respect of the river ground, it is movable by an adjustment gear.

Description

Hydroelectric power plant

This invention relates to hydroelectric power plants for the production of electricity using the water flow of a river, without an accumulation lake, with a movable underwater dam for a hydroelectric power plant.

Hydropower plants have been built in rivers for a long time. Usually, the water flow of the river is blocked by a dam, and a reservoir is made at the first higher level. The water then passes through the central part to the second lower level. In a power plant, water passes through a pipe that leads to a turbine that produces electricity, before the water is returned to the water stream. The construction of the reservoir has a bad impact on the environment and society. For example, a dam is a barrier in the movement of river animals from the upper to the lower reaches of the river and vice versa. Newer dams often have expensive "fish guides" or "fish ladders". In addition, coastal ecosystems are constantly threatened by erosion. Finally, the water in reservoirs is usually warmer in winter and colder in summer than it is when there is no dam. And since this water flows into the river, the changed temperature negatively affects the river temperatures.

In order to overcome these shortcomings, hydroelectric power plants were designed that do not need a reservoir to produce electricity. These power plants take advantage of the natural energy of the water flow initiated by the gravitational fall of the river bed. Therefore, there is no need to flood the upper course of the river, and no need to displace people, and natural habitats and productive properties have not been wiped off the face of the earth.

The state-of-the-art hydroelectric power plant shows, for example, that the dam support is completely submerged in the river and anchored to the riverbed. Ships, ice, floating logs and the like can pass by the dam support or can sail over it. A generator and underwater cables for power transmission are located in the dam support. In the carrier there is also a funnel passage, on the inlet side of a large diameter with an outlet opening of a smaller diameter. On the driveway there is a drive shaft with turbine blades, as well as a generator and a transformer. The river flow creates hydrodynamic pressure on the funnel, which, due to its position, acts on the turbine blades, which are obtained

they transform hydropower into mechanical power and then into electrical power.

The support of classic storage dams is supported in the river bed. The speed of the water flow is significantly reduced, therefore the efficiency of the classic dam is low. Maintenance of the storage dam support is difficult, it cannot be easily adapted to the changing circumstances required for this conceptual solution.

The object of this invention is to provide a hydroelectric power plant, with moving dam elements that overcome the difficulties of known power plants and that reduces negative impacts on the environment, shows a high level of performance and profitability during installation and its future operation.

This and other objects, which will appear in the further description, were achieved by means of a hydroelectric power plant and elements of a movable underwater dam as stated in the attachment of the patent claims. Desired embodiments are defined in the dependent claims.

A hydropower plant for electricity production, which is to be placed in the river's watercourse, contains several components, which are designed and adapted to be placed at the place of electricity production. Most of them are at least partially placed under water. The totality of installed components constitutes a hydroelectric power plant. According to the invention, the hydroelectric power plant contains at least two opposite dam walls, parts towards the shore placed on opposite sides of the river, which contain the coastal end located on the opposite sides of the river bank, and there is also a free end that extends towards the river. There is also a water passage and at least one element of the movable underwater dam between the free ends of the two opposite walls of the dam, when in the installed position. This means that each dam wall is placed in the river in such a way that one end is connected to the coast line, and the other reaches at least partially towards the middle of the river, as required by the design task and the type of riverbed. It would be best if the two opposite walls of the dam were placed with their ends in the direction of the rim of the river flow, which means that the ends of the machine units use the existing bed of the river. The two opposite walls occupy an angle of 45 degrees for slower rivers and up to 30 degrees for faster water flows in relation to the axis of the mother river. In general, the dam walls extend from the coastal sides in the direction of the mother river, which means that they make an angle greater than 90 degrees between the direction of the incoming water flow and the dam wall on the side of the waterway. Thus the water is said to flow through the water passage between the two opposite walls of the dam.

The walls of the dam may contain small mechanisms that allow some of the water to pass through them, instead of through the water passage between the walls of the dam. Thus, the increased flow of river water has less impact on hydroelectric power plant installations. The advantage is that the mechanisms can have a movable closure, which partially or completely closes the mechanisms, so that the flow of water in the river and through the passage can be controlled, neutralizing stagnant water downstream of the dam wall. In order to further reduce the cost of building a hydroelectric power plant, due to reduced water pressure, the walls of the dam can have structural cavities that are filled and emptied with water from the river using the principle of connected vessels. The walls of the dam are made of reinforced concrete, they are rigidly tied to the bottom of the river with a strip foundation and have a rigid connection with the machine unit.

Furthermore, the hydroelectric power plant contains at least one machine unit, for example in the form of a machine room located on one of at least two opposite walls of the dam, which contains at least one generator unit for generating electricity. The machine unit or machine room is connected to the ground cable to transport the generated electricity to consumers. The engine room or room is at the free end of the weir wall, close to the water passage and the position of the moving weir elements. It would be best to be positioned at the end of the dam wall, above the surface of high water, which means opposite the river bed. The hydroelectric power plant also has a control system, which controls the operating parameters of the hydroelectric power plant. The control system generally has sensors, software programs as well as systems for managing the position of the dam. It can be located in the engine room or room and can be connected by remote control to all the built hydroelectric power plants on the river section and the current needs of the electricity market, in order to relieve the system of the load of the single production of the hydroelectric power plant and extend its life. In addition, the mechanical units at the ends of the dam walls are the basis for the funnel-shaped water flow, which directs the water flow over the elements of the movable underwater dam to the crossing over the dam. The machine units between the two opposite walls of the dam are placed parallel to the axis of the water flow; they are also placed parallel to each other to achieve a quality connection between them

elements of the movable underwater dam.

At least one element of the movable underwater dam is placed in the water passage itself and the aforementioned funnel passage when the hydroelectric power plant is in the installed position. In case there are several elements of the moving dam, they are connected to each other. The movable dam element has a lower end that is located on the river bed and an upper end that is movable in height relative to the river bed. The upper end, for example, can be raised or lowered with the help of a device for adjusting the position of the dam itself, which can be a pump, a hydraulic device or, as in the provided example, a positioning shaft with cables and mechanical drive force. Thus, the surface of the movable underwater dam is placed at right angles to the axis of water movement and water pressure of the river flow, it can be adjusted to specific conditions, such as higher or lower water level of the river. The elements of the movable dam can always be positioned in the water at an optimal height, for example, directly towards the water flow, without changing their position in the direction of the machine unit or the room.

According to the invention, the supporting elements of the moving dam should be of a flat elongated rectangular shape, such as a plate with the necessary air chambers as explained further. The supporting elements of the movable dam are segmentally divided into chambers, and they are segmentally arranged alternately in relation to the position of the turbine blade. Bearing elements can be made of recycled plastic with metal structural reinforcements. The lower end of the load-bearing elements of the dam is centrally located on the river bed, so that the movable dam elements include an adjustable sharp angle between the river bed and the movable dam elements downstream. In this way, the upper end of the dam elements is distant from the river bed at different heights, which is a direct consequence of the distance from the variable height of the water surface, which is different in time intervals. Thus, the load-bearing elements of the movable dam act as a ramp for additional narrowing of the water flow, thereby additionally accelerating the flow of water in the necessary part of the upper end of the movable dam. The ends of the supporting elements of the dam are connected and supported by bearing housings with the upper and drive shafts, which are anchored to the ground of the river with a strip foundation. Thus, the supporting elements of the dam can rotate around the drive shaft with bearings at one end of the dam. The height of the upper end of the moving weir and the required sharp angle for optimal operation can be controlled using the process control system. The underwater dam element position control system includes a positioning shaft that can be connected to the river bed via inclined piles and bearings. It serves to move the dam up and down to a certain position by means of a rotary movement in both directions, winding and unwinding the cables by means of a given current mechanical force. The reinforced concrete strip foundation is placed transversely from the river flow, it has a concrete outlet shaped along its entire length to direct the entire flow of water to the upper part of the movable dam. The moving dam is generally made of prefabricated, more standard elements, with their assembly on site.

In general, the presented hydroelectric power plant can be used in natural rivers, but also in artificial water channels, which are, for example, a branch of a river. An innovative solution for obtaining a renewable source of electricity from a hydroelectric power plant with a movable underwater dam, as described above in lowland areas and other larger rivers, is based on the principle of hydrodynamic pressure from the potential energy of water movement in the river on the elements of the movable dam, where the acceleration of the flow of water (m3/s) in the river is created by increasing its flow speed (m/s), through the cross-sectional area (m2) of its flow.

The construction of a hydroelectric power plant in accordance with the invention does not require hilly terrain, as does the construction of a classic reservoir lake. Positioning of one or more elements of the movable dam and dam walls in the river bed does not require special preparation of the river bank. Dams are made in accordance with the calculation of the possibilities and capacity of the river flow and the shape of the riverbed. Compared to the power plant on the reservoir and the gravity drop of the water, this hydroelectric power plant has the same or higher level of production in MWh.

A hydroelectric plant according to the present invention is particularly useful in lowland rivers. The geographical potential of lowland rivers is enormous. The lowland river is a collector of all smaller and larger watercourses, which means that more or less throughout the time unit, this river has a constant or almost constant intensity of river flow. A hydroelectric plant according to the invention can be sold as a structure and can be easily installed in different environments. There is no silt blocking or retention, and finally, fish migration is possible 100% without killing fish due to electricity generation. In the case of the example of the Mississippi River, the capacity would be more than 100,000 MW of electricity with permanent exploitation. One installed hydroelectric power plant would have a power of more than 200 MW with a constant production of 90% or more of the exploitation of the installed power.

It is an advantage if the mother of the river flow has a concentrated flow in the elliptical shape of the river bed, and if this is not the case, the foundation of the hydroelectric power plant can be buried in the river bed, for example, to achieve the necessary depth for the passage of vessels in case of low water level. Both types of river bed are good for setting up a movable dam, but different design parameters apply for using the potential energy of the water. The installation of hydropower plants should be concentrated in places where there are not too many water obstacles. Locations for the installation of a series of hydropower plants along the river course should be calculated based on the average annual water flow, so that the initial water velocity at the first power plant and for example the 33rd power plant is the same or similar. They can be linked by control software so that all the locations of the moving barriers can be adjusted to achieve optimum performance in changing conditions. Such a series of hydroelectric power plants in the riverbed controlled by software and containing a series of constructions of movable underwater dam elements is better in the case of low river water levels and reduced electricity consumption at night. A series of hydroelectric plants can slow down the flow of water, increase the water level in the section of the river where the hydroelectric plants are located, so that the same amount of water can be used for the production and daily consumption of electricity. We can say that at low river water levels, power plants can serve for the concentrated management of the river flow regime for the needs of the waterway and systemic management for concentrating excess water on the river section for a longer period of use. The design and construction of dozens of hydroelectric power plants in a row stabilizes the production of electricity in all weather conditions, especially in times of drought. For example, in the Danube river there are oscillations in the flow from 2,500 (m3/s) to over 10,000 (m3/s). It is possible to realize projection parameters of 4,000 (m3/s) with a minimum height of the underwater dam and water surface of 2 m. This is suitable for navigation on a river that would be constant rather than seasonal. The difference between extreme drought conditions is (4,000 - 2,500 = 1,500 (m3/s)). The difference can be compensated by the management system - by raising the underwater dam up to, for example +- 1m water column and thus slowing down the water flow, accumulating water during the night when energy consumption is reduced and using it sparingly during production and energy consumption during the day. Throughout the year, we have regulated river traffic and stable electricity production during the dry season.

In case of a flooded river bed with a high water flow potential, the river can be narrowed with embankments, deepened and shaped by the machine bed of the mother river, which is also a good solution for the waterway. Embankments also serve as communication for the operation and maintenance of hydroelectric power plants in a row, they contribute to the protection of the flooded area from high water, they can influence the width of hydroelectric power plant construction by lowering their construction cost.

The device for adjusting the position of the moving dam element in its supporting elements contains pressure chambers, more precisely air pressure chambers, in which the pressure force in the chambers is adjustable to the predetermined height of the underwater dam. The adjustment device can work in conjunction with the position control system of the underwater dam element. The volume of air in relation to the displacement of water from the chambers creates a pressure-buoyancy force in a moving underwater dam, where the process is controlled by means of a compressor, a control system and a system for managing the position of the underwater dam element. Depending on the pressure and amount of air in the chambers of the underwater dam elements, there is more or less buoyancy force that makes the upper part of the dam move in the direction of the river surface, while the lower end is attached to the bottom of the river. In any case, the buoyancy force of an underwater dam should be 10% higher than the required maximum force to neutralize a series of forces that affect the position of the dam itself. The force that neutralizes the 10% excess buoyancy force and stabilizes the position of the underwater dam is the counter force of pulling by means of shafts with cables to the required operating position. The air pressure in the chambers is, for example, slightly above 1 bar, which also depends on the depth of the river, and it is necessary to push the water out of the chambers, where the water naturally circulates alternately with the air as needed. The required air pressure is obtained from the compressor with storage air through the reduced incoming mechanical force from the drive shaft itself, which provides the operating force to the compressor through the transmission. The compressor is located in the engine room and is connected to the necessary systems, high pressure pipes connected to the air chambers in the moving dam element. The storage of compressed air can be in one part of the moving dam element and in the upper shaft under high pressure, so that the air can be applied more quickly by the steering control.

In the preferred form of the hydroelectric power plant, the movable dam element has single moving parts for power generation, which are coupled to the generator by means of a transmission at the base of the engine room. For example, a moving weir contains a rotating belt and turbine blades, which are mounted and movable along the moving weir. A rotary belt segment, for example, has a length of several meters and a width of several decimeters. The segments can be connected by a hinged alternating connection with a metal rod. With its length of several meters, the rotary belt is tensioned and articulated from a series of segments via four gears of the drive and upper shaft. On the rotating belt, the turbine blades are articulated in a row with the arrangement, width, angle and design according to the design task, if necessary they can be knocked down from the lower side of the movable dam. The turbine blades and the rotating chain belt are driven by water power acting at an approximate 90 degree angle to them, thus acting on at least one element of the movable weir. Between the turbine blades there are profiled openings for the unhindered passage of part of the flowing water in order to distribute the entire flow of the river over the largest possible surface area of the turbine blades. That's why the rotary belt is placed along the axis of the dam in the direction of the water flow. The blades of the turbine carry rotating belts, which circulate around the drive shaft at the lower (bottom of the river) end of the dam and around the upper shaft at the upper (at the top of the water level) end of the dam. Turbine blades are the basic parts of the hydroelectric power plant for collecting the hydrodynamic water pressure at the funnel-shaped position of the moving dam in such a way that the speed of the rotary belt depends on the part of the use of the obtained water force and the software management that sets the current parameters of electricity production. It is best to transfer the obtained mechanical energy to the drive shaft exclusively by means of segmental rotary belts placed over two chains and four gears. The drive shaft is a drive spindle (circular movement) that transmits the mechanical force obtained from the movement of the rotary belt with turbine blades, the rotational forces of movement to the reducer and generator, fixed with bearing housings for the belt foundation.

Depending on the angle at which the movable dam is, the driving force of the water acts so that the turbine blades can work optimally and uniformly. In the lower part of the machine unit, the end of the drive shaft ends in a housing with bearings that stabilize and center the travel of the drive shaft to transfer a large amount of mechanical energy obtained to the reducer, using multi-row gears and chains. To convert the force of the water into electricity, the turbine blades of at least one segment of the moving dam can be coupled to a generator via transmission equipment. The sprockets of the turbine blades are made of profiled metal, they are laterally connected with the segments of the rotating belts, they are tightened over the gears of the drive and upper shaft. The chains transmit and synchronize the operation of all segments of the turbine blades with the gears of the drive shaft, because the water force on the moving dam acts in a variable direction and intensity, where such a connection does not allow the oblique operation of the turbine blades.

The hydroelectric plant further according to the invention contains two machine units or rooms, one for each of the two opposite walls of the dam. Two machine units or rooms are connected to each other. For example, engine rooms and their generators can be coupled to each other by means of a movable dam and a drive shaft. The engine room also has at least one shaft connected to the reducer and generator by transmission equipment. The reducer and generator, with transmission equipment can be part of the generator unit for the production of electricity. The transmission equipment may include at least one or more gears that are connected to the sprocket, which in turn are connected to at least one other gear of the reducer. Multi-row gears with sprockets are required to transmit the large amount of mechanical energy obtained from the rotational force of the drive shaft.

The water flow, guided and accelerated by the moving dam, can also be introduced into a conventional generator, such as a turbine tube.

In the example of the Mississippi River, which has an average annual flow of 15,000 ( m3/s ), with an average velocity of 1.5 ( m/s ), and with a river drop of 0.1 ( m ) per 1000 ( m ), the following calculation can be made:

- average depth of 10 m' = 100,000 m' of river flow.

- 100,000 m' x 10,000 m3/m = 1,000,000,000,oo m3 = T of hydropotential energy moving at a speed of 1.5 ( m/s ) and with significant acceleration at

location of the underwater dam.

Such an approach to the construction of a hydroelectric power plant is profitable for the following reasons:

- permanent and sustainable-renewable electricity production system,

- 100% ecologically clean energy, which does not interfere with the flow of the river, and the project fits into the structure of the natural environment of the water course, - production is 90% or more of the installed MW with predictable project parameters and profitability of investment within 2 to 4 years.

The planning of the movable dam is defined by the factor of the size of the river, which primarily refers to the speed of the water flow (m/s) and the amount of flow of the water flow (m3/s), but also the relief cross-section of the river bed. For example, gently sloping terrain makes a river slower, shallower, and wider with slow water flow, while higher terrain makes the river fall faster, deeper, and narrower with faster water flow. The movable hydroelectric dam according to the invention is able to adapt to both types of terrain.

The desired form of the invention will be described in the accompanying drawings, which may explain the principles of the invention, but will not be limited to the invention itself. The drawings illustrate: Figure 1, a schematic diagram of a river with a hydroelectric power plant in accordance with the proposed invention,

Figure 2 is a schematic longitudinal view of a moving dam in accordance with the invention, and Figure 3 is a schematic view of a moving dam and generator unit in accordance with the invention.

In Exhibit 1, a hydroelectric power plant in accordance with the invention shows what is installed in the water course of the river. The hydropower plant contains two opposite walls of the underwater dam (1; 2). Each wall of an underwater dam contains a coastal end (3) located on the river bank and a free end (4) that extends downstream. The coastal end can be connected to the embankment. The underwater dam wall (1) and the underwater dam wall (2) are located on opposite coastal sides. Between the free ends (4) of the two opposite walls of the underwater dam (1; 2) there is a water passage (5). Each underwater dam wall has a machine unit (6). The machine unit is located at the free end (3) of the dam walls. The machine unit contains the components of the generator unit for generating electricity. The control system (shown in the form of a cube) for controlling the operating parameters of the hydroelectric power plant can be located in at least one machine unit (6). The control system can have a software system for managing various parameters necessary for the operation of the hydroelectric plant and nearby hydroelectric plants. At least one movable dam (7) is located near the water passage (5). The movable dam (7) contains the lower end (8) which is placed on the river bottom and the upper end (9) which is moved up depending on the river bottom shown in figure 2.

The movable weir (7) is used to narrow the water flow into a funnel shape. Thus, the water flow is forced in accordance with the position of the machine unit (6) and the movable dam (7) to increase the speed of the water flow through the water passage (5). The regular speed of the river is, for example, 2.5 (m/s). Between the upper end (9) and the surface of the water, the speed of the water accelerates to 6.0 ( m/s ). In the part below the moving dam on the lower side, the speed is only 0.1 (m/s).

For example, on both sides of the river, an embankment with a road to underwater dams can be built lengthwise, about 2 ( m ) above the highest water level. The walls of the underwater dam (1; 2) can be designed as reinforced concrete walls, which can be built from both embankments towards the water course of the river. The walls of the dam can be used for road communication towards the machine unit. The angle of the dam walls to the water flow is chosen so that they have little effect on the water flow, if possible. With a height of cea. 2 ( m ) above the highest water level, the dam walls drive the direction of the water like a funnel towards the moving element of the dam. By changing the water level in the river, the water level at both ends of the dam wall remains the same, and thus the water pressure on both sides is the same, the dam walls suffer only from the torsional pressure of the water in the river. The walls of the dam can have a relief shape and design with special colors, they can be adapted for recreational tourism, fishing needs and as a place for mooring vessels on the lower side of the wall.

The piles can be used to connect all components of the hydroelectric power plant to the river bed, and the dimensions are determined in accordance with the project. For example, pile installation can be done by drilling to a certain depth, then the builders organize a controlled explosion, under the pressure of the explosion water compresses the weak material, concrete fills the newly created space, which serves to expand the pile foundation against the vertical force of the underwater dam.

In the illustration, the machine unit (6) is located at the end of the underwater dam wall (1). In its position, it is connected to the movable dam (7) and the machine unit (6) on the opposite wall of the underwater dam (2). This is one of the main purposes of the movable dam (7), to manage the water flow through the hydroelectric power plant and to increase the water flow rate. Thus, the underwater dam element position control system serves to move the underwater dam element in both directions, up and down. Also, the adjustment device helps to position the movable underwater dam element in the water flow. The machine unit can contain the components of the reduction system if necessary for the operation of the hydroelectric plant, for example for the transmission of mechanical power to the generator. For example, the drive shaft (10) enters the lower level of the machine unit (6), where it ends with aligned gears. The gears transmit the produced mechanical force via the sprockets to the other aligned gears of the reducer (19) (shown 3). The reducer stabilizes the produced mechanical force and converts it into relevant (rpm). The reducer is directly connected to the generator for the production of electricity (MVVh). The existing mechanical force from the reducer is transmitted partly as a controlled force by means of a chain and gears to the control system of the movable underwater dam (7). The operating parameters of the work are transferred to the software control with adequate cables and they raise and lower the underwater dam, as needed, using only mechanical force. In this way, the mechanical force was used directly from the drive shaft so that the position of the underwater dam solely depended on the river flow. For example, an underwater dam with its position should not endanger the waterway at any time if the electronic system fails.

The control system (17) with sensors and software programs for managing all production and safety processes, among other things aims to harmonize the operation of the hydroelectric power plant with the operation of a series of hydroelectric power plants, is equipped with a series of sensors that show whether there is a swimmer, boat or ship in the primary zone of the dam, so that the system can quickly react to the newly created situation.

The control system reacts to the received series of information with a software program in order to manage the units of the hydroelectric power plant. For example, it engages the required mechanical force from the drive shaft and by means of a series of reduced transmissions gives force to the system for the position of the movable underwater dam element (7) which is under the underwater dam (1) and controls the position management system of the underwater dam element. Within a few minutes, the element of the underwater dam (7) is moved up and down to the set positions by the drive shaft of the system. Thus, the control system is responsible for the position of the element of the underwater dam and the corresponding supporting cables of the underwater dam, using the acquired reduced mechanical force that sets the speed and power for the movement of the underwater dam.

The positioning shaft (20) of the underwater dam position system is made along the entire length of the underwater dam element (7); made of metal with an entry into the housing of the machine unit (6), it is attached with bearings for inclined piles. Inclined piles, which form the foundation (11), are reinforced concrete, profiled and arranged as needed, depending on the composition of the bed bottom and the projected force of the air chambers (12) of the movable underwater dam element (7), which can be greater than 100 (t). The positioning shaft (20) of the underwater dam position system is cabled to all bearing housings of the upper shaft (15) of the movable underwater dam element (7). We can mention that the air chambers (12) of the movable underwater dam, depending on the size of the hydroelectric power plant, have a buoyancy force of more than 1,000 (t). The purpose of the expansion of the piles of the strip foundation is to prevent the eventual pulling out of the underwater dam from the foundation (11) at the bottom of the river with the connection in the ground.

The walls of the engine unit, which are located above the water level, can be a key point for the transmission of signals needed for river navigation. They may be indicated by lights or other signaling equipment necessary for navigation of ships and navigation benchmarks. They can have an autopilot system installed for a controlled, self-guiding, mapped river traffic management system.

Figure 2 shows a schematic view of a movable underwater dam (7) installed on the riverbed. The movable underwater dam (7) has a flat elongated shape.

Based on the obtained parameters of the river flow, we take the mean values by which we design the width of the underwater dam with the known minimum height of the water column, roughly 2 (m) from the water surface to the top of the movable underwater dam. With the known height of the water column, the mean flow of the river, the required accelerated flow of 6 (m/s), we get the length of the underwater dam. The width of the underwater dam in large rivers is several tens of meters, as such it uses the flow of water so much that the flow of the river downstream does not interfere with the next catch of the movable underwater dam. The achieved water velocity is collected concentratedly over the entire upper width and length of the turbine blades (13). The height and mutual distance of the turbine blades (13) depends on the design slope of the movable underwater dam and the angle at which the water force acts, with distributed forces on each turbine blade individually. The width of the underwater dam depends on the relief of the river, which gives it the speed of flow minus the loss of such energy from the uneven relief of the river bed. The surface of the underwater dam in operation captures a smaller part of the energy of the accelerated water, so that the water under the pressure of the incoming water creates a uniform and stabilizing flow of water after the underwater dam in the zone of which there is low pressure due to the flow of the river, such downstream conditions would be favorable for the next downstream hydroelectric power plant.

The movable underwater weir (7) is placed at an acute angle (A) between the river bed and the movable underwater weir downstream. The lower end (8) of the movable underwater weir (7) is centrally located on the river bed by means of the positioning shaft (20). Therefore, the movable submersible dam (7) comprises housings with bearings located on the bottom of the river (11), placed on a strip foundation (11) so that the submersible dam can rotate around the drive shaft (10). A movable underwater dam is built from light materials such as recycled plastic, rubber, aluminum, iron, etc.

An adjustment device is provided to adjust the angle (A) and the height of the upper end (9) of the movable underwater dam (7). In this case, the adjustment device is provided partly by air pressure chambers (12), which are placed in the construction of the movable underwater dam (7). The pressure in the chambers (12) is adjusted using compressed air from the compressor (18). The buoyancy force in the chambers lifts the upper end (9) of the movable underwater dam (7). In this case, the pressure chambers are placed in a segmental array of a movable underwater dam, connected so that the chambers can be pressurized by compressed air with a uniform pressure. For example, a reducer transmits mechanical force at certain intervals to a compressor to produce a uniform pressure, where it is blown into pressure chambers by means of high-pressure pipes. The thickness of the supporting partition with air chambers is exclusively related to the project to neutralize a series of river forces that act on the very position of the element of the movable underwater dam. Also, the underwater dam element position control system serves to move the dam element up and down.

As shown in Figure 2, the movable weir (7) contains multiple turbine blades (13), held by a rotating belt (14), which moves around a drive shaft (10) at the lower end (8) of the weir and an upper shaft (15) at the upper end of the weir (9), which can be filled with constant balance air. The water force of the flow acts on the blades of the turbine (13) in the middle and on the upper side of the movable underwater dam (7), and that side is facing the upper course of the river, while the blades of the turbine (13) at the bottom of the movable underwater dam are protected from the water flow, facing the bottom of the bed, without water flow, due to their shape and design they slide smoothly through the water. Thus, the water force of the flow drives the blades of the turbine (13) on the rotating belt (14), and the rotating belt drives the upper (15) and the drive shaft to generate electricity. Thus, the turbine blades of the mobile underwater dam have a synchronized operation with the generator. The drive shaft (10) can be coupled to the generator by means of transmission equipment.

It is good that the height of the movable underwater dam is adjusted so that the minimum height above the turbine blades to the water surface is 2 (m) or more. This is important for free-ranging fish migration. As shown in figure 2, the funnel effect of the movable underwater dam accelerates the water flow and therefore the water pressure in the area of the upper end (9) of the movable dam is more intense.

In addition to the mechanical force generated by the flow of water, the operation of the adjustment equipment and the generator can also be controlled by the control system software, which is supervised by a worker who has an open view over the hydroelectric plant to the river and the walls of the underwater dam. In addition to controlling the production of electricity, the control system is responsible for safety in and on the river, and next to the hydroelectric plant, including swimmers and all types of vessels. The software is designed to coordinate the operation of a specific hydroelectric plant and the operation of hydroelectric plants along the river course. Therefore, the hydroelectric power plant can be equipped with various sensors that indicate the appearance of swimmers, boats or ships in the primary area. In that case, the system is ready to respond immediately to changes in conditions and, for example, to lower the moving element of the underwater dam. Large ships generally have to have depth sensors, and they automatically show the depth of the draft due to the cargo they are carrying. This information can be used to automatically lower the mobile underwater dam by about 0.3 ( m ) from the bottom of the vessel. A movable breakwater adjustment device ensures that the breakwater is lowered, for example, for a ship to pass over it. Raising an underwater dam practically does not take more than a few minutes. Adjusting the movable underwater dam by filling the pressure air chambers neutralizes the forces of the water flow and thus controls the position of the upper end of the movable underwater dam under water. Thus, a movable underwater dam can also be adjusted in case of changing water force of the flow and react to the change of water level.

In Figure 3, is a schematic view of a movable underwater dam (7) with an upper shaft (15) and a lower drive shaft (10), which are connected to the generator unit. The generator unit contains, among other things, a control system unit (17), a compressor (18) and a reducer (19). The reducer (19) can be coupled to the drive shaft (10) by means of transmission equipment. The transmission equipment includes at least one gear connected to the sprocket, which is connected to at least one gear of the reducer. For example, a movable underwater dam is connected to the bearing housing at a distance of 20 ( m ) due to the connection to the drive shaft and the foundation of the dam. The drive shaft (10) is made of standard parts in several segments, about 20 ( m ) long, with two gears for each segment of the shaft. The length of the drive shaft can be slightly longer than the movable underwater dam (7). For example, the chain is made of iron, it is connected to the segments of the turbine blades and with two gears for both shafts (both upper and lower), in order to transmit and synchronize the operation of the turbine blades with the drive shaft, because the water force on the underwater dam behaves differently in different positions, where such a connection does not allow irregular, broken operation of the turbine blades. The drive shaft (10) and the positioning shaft (20) can be in a coaxial position or parallel to each other at the lower end of the underwater dam element (7).

The upper end (9) of the movable underwater dam (7) may contain an electrical power generator, and the generated current may be conducted to the machine unit by a cable (16) as shown in Figure 2.

In lowland rivers, in general, the pressure on the hydroelectric power plant is constant, so that every part of the cross-section of the river flow is under the influence of the hydropotential energy of the water movement caused by gravity, the fall of the river bed, and the incoming and outgoing water flow. In lowland rivers, the force of water pressure has an approximate constant value for several hours, which, for example, in the case of the Danube River, is 1000 (m) x 3,000 (m3/m) = 3,000,000 (m3) with a movement speed of 2 (m/s). The velocity of the natural water flow of 2 ( m/s ) can be increased by a movable underwater dam to about 6 ( m/s ), where the reached water velocity is concentrated in front and on the upper surface of the turbine blades. The central value of the natural water flow is about 3,000 ( m3/m ) x 2 ( m/s ) = 6,000 ( m3/s ), and the flow generated by the moving underwater dam is about 9,000 ( m3/m ) x 4 ( m/s ) = 36,000 ( m3/s ). It can be concluded that the useful hydropotential of energy is 6 times more smoothly captured than the entire potential of the energy section of a natural river. Thus, in the Danube River, a movable underwater dam would produce about 100 MW with a projected utilization of 90% and more of electrical energy generation, which clearly exceeds the potential of conventional power plants.

In order not to create a vortex loss of the hydropotential energy of the river water, the construction of the underwater dam was completely placed at the place of the funnel-shaped water passage, as in the example of the Danube river, the length of the movable underwater dam would be more than 300 (m) and the width of more than 40 (m). The joint of the construction of the movable underwater dam and the bearing walls of the machine unit should be parallel on both sides at a distance of several tens of decimeters, which are necessary for the design due to the partial expansion-contraction of the construction due to the change in water temperature.

POSITION ON DRAWINGS

1 underwater dam wall

2 underwater dam wall

3 coastal area

4 free end

5 waterway

6 machine units

7 movable underwater dam

8 bottom end

9 upper end

10 drive shaft

11 river bottom

12 pressure chambers

13 turbine blades

14 rotary lane

15 upper shaft

16 electric cable

17 units of the control system

18 compressor

19 reducer

20 underwater dam position control system drive shaft 21 underwater dam control system A angle

Claims (15)

1. The hydroelectric power plant for electricity generation, which should be installed in the water course of the river, contains: a. at least two opposite walls of the underwater dam (1; 2) containing the coastal end (3) placed on the opposite banks of the river and the free end (4) extending towards the river with a water passage (5) between the free ends (4) of the two opposite walls of the underwater dam (1; 2), when in the installed position, b. at least one machine unit (6) on one of at least two opposite walls of the underwater dam (1; 2), which contains at least a generator unit for generating electricity, and c. control system for controlling the operating parameters of the hydropower plant, d. where at least one element of the movable underwater dam (7) is placed near the water passage (5), which has a lower end (8) which is placed on the bottom of the river and an upper end (9) which is movable in height depending on the river bottom. 2. Hydroelectric power plant according to patent claim 1, where at least one element of the movable underwater dam (7) has a flat elongated shape and the lower end (8) of the underwater dam (7) is hinged and rotatably placed in the river bed so that the underwater dam element (7) occupies an adjustable acute angle (A) between the river bed and the underwater dam element downstream. 3. Hydropower plant according to patent claim 1 or 2, where a device is provided for adjusting the height of the upper end (8) of at least one underwater dam (7), which contains air pressure chambers (12) placed in a movable underwater dam (7), where the buoyancy force of the air pressure chambers (12) is adjustable to a predetermined height of the underwater dam (7). 4. Hydropower plant according to patent claim 3, where the pressurized air chambers (12) are designed with a series of segmentally connected chambers, which are filled with uniform air pressure. 5. A hydroelectric plant according to the preceding patent claims, wherein the movable underwater dam (7) contains turbine blades (13) driven by water force. 6. Hydroelectric power plant according to claim 5, where the turbine blades (13) carried by the rotating belt (14) move around the drive shaft (10) at the lower end (8) of the movable underwater dam (7) and the upper shaft (15) at the upper end (9) of the underwater dam (7). 7. Hydropower plant according to patent claims 5 and 6, where the turbine blades (13) of at least one movable underwater dam (7) are paired with the generator. 8. Hydropower plant in accordance with one of the previous patent claims, where the two opposite walls (1; 2) are at an angle in the direction of the water flow, so that they extend from the coastal sides towards the water flow, the beginning of the mother river. 9. Hydroelectric power plant according to one of the preceding patent claims, where the machine unit (6) is located at the free end of the underwater dam wall opposite the river bottom. 10. A hydroelectric power plant according to one of the preceding patent claims, where there are two machine units (6), one for each of the two opposite walls of the underwater dam (1; 2), and where the two machine rooms (6) are connected to each other. 11. Hydroelectric power plant according to one of the previous patent claims, where the machine unit (6) contains at least one drive shaft (10) connected to the reducer (19) and the generator by means of transmission equipment. 12. Hydroelectric power plant according to one of the previous patent claims, where the transmission equipment contains at least one gear with a chain, which is connected to one gear of the reducer (19). 13. Hydroelectric plant according to one of the previous patent claims, where the control system is placed in the machine unit (6). 14. An underwater dam for a hydroelectric power plant, having a lower end (8) which is pivotally mounted on the river bed and an upper end (9) which is remote from the river bed, where the upper end (9) is moved up and down in height relative to the river bed by means of an adjustment device. 15. An underwater dam containing at least one of those mentioned in patent claims 3 to 7. 1. The hydroelectric power plant for electricity generation, which should be installed in the water course of the river, contains: a. at least two opposite walls of the underwater dam (1; 2) containing the coastal end (3) placed on the opposite banks of the river and the free end (4) extending towards the river with a water passage (5) between the free ends (4) of the two opposite walls of the underwater dam (1; 2), when in the installed position, b. at least one machine unit (6) on one of at least two opposite walls of the underwater dam (1; 2), which contains at least a generator unit for generating electricity, and c. control system for controlling the operating parameters of the hydropower plant, d. where at least one element of the movable underwater dam (7) is placed near the water passage (5), which has a lower end (8) which is placed on the bottom of the river and an upper end (9) which is movable in height depending on the river bottom, e. where at least one element of the movable underwater dam (7) contains turbine blades (13) which are driven by water force and which are coupled to a generator. 2. Hydroelectric power plant according to patent claim 1, where at least one element of the movable underwater dam (7) has a flat elongated shape and the lower end (8) of the underwater dam (7) is hinged and rotatably placed in the river bed so that the underwater dam element (7) occupies an adjustable acute angle (A) between the river bed and the underwater dam element downstream. 3. Hydropower plant according to patent claim 1 or 2, where a device is provided for adjusting the height of the upper end (8) of at least one underwater dam (7), which contains air pressure chambers (12) placed in a movable underwater dam (7), where the buoyancy force of the air pressure chambers (12) is adjustable to a predetermined height of the underwater dam (7). 4. Hydropower plant according to patent claim 3, where the pressurized air chambers (12) are designed as a series of partitions with a segmental connection of the chambers, which are filled with uniform air pressure. 5. A hydroelectric power plant according to claim 1, wherein the turbine blades (13) carried by the rotating belt (14) move around the drive shaft (10) at the lower end (8) of the movable underwater dam (7) and the upper shaft (15) at the upper end (9) of the underwater dam (7). 6. Hydropower plant in accordance with one of the previous patent claims, where the two opposite walls (1; 2) are at an angle in the direction of the water flow, so that they extend from the coastal sides towards the water flow, the beginning of the mother river. 7. Hydroelectric power plant according to one of the previous patent claims, where the machine unit (6) is located at the free end of the underwater dam wall opposite the river bottom. 8. Hydroelectric power plant according to one of the preceding patent claims, where there are two machine units (6), one for each of the two opposite walls of the underwater dam (1; 2), and where the two machine rooms (6) are connected to each other. 9. Hydroelectric power plant according to one of the previous patent claims, where the machine unit (6) contains at least one drive shaft (10) connected to the reducer (19) and the generator by means of transmission equipment. 10. Hydroelectric power plant according to one of the previous patent claims, where the transmission equipment contains at least one gear with a chain, which is connected to one gear of the reducer (19). 11. Hydroelectric plant according to one of the previous patent claims, where the control system is placed in the machine unit (6). 12. An underwater dam for a hydroelectric power plant, having a lower end (8) which is pivotally mounted on the river bed and an upper end (9) which is remote from the river bed, where the upper end (9) is moved up and down in height relative to the river bed by means of an adjustment device. 13. An underwater dam that contains at least one of those mentioned in patent claims 3 to 5.