WO2007093416A1

WO2007093416A1 - Very low-head hydroelectric plant

Info

Publication number: WO2007093416A1
Application number: PCT/EP2007/001314
Authority: WO
Inventors: Jean-Pierre Belliard
Original assignee: Jean-Pierre Belliard
Priority date: 2006-02-16
Filing date: 2007-02-15
Publication date: 2007-08-23
Also published as: FR2897397A1

Abstract

The invention relates to a very low-head hydroelectric plant (100), the head being measured between the upstream level and the downstream level of a watercourse, the hydroelectric plant (100) comprising: - a bearing structure (104a, 104b) that is fixed with respect to the banks of the watercourse; - a chassis (130) mounted on the bearing structure (104a, 104b) and - at least one electricity-generating assembly (122a, 122b) that is fixed to the said chassis (130), each current-generating assembly (122a, 122b) comprising: - means (112, 114) for channelling the head; - an electric generator (102); - a drive means (118) positioned inside the channelling means (112, 114) and rotated by the falling water; and - a rotation shaft (120a, 120b) substantially parallel to the stream lines of the falling water, the first end of which is secured to the drive means (118) and the second end of which has means of coupling to the electric generator (102); the hydroelectric plant (100) being such that the second end extends above the upstream level and that the electric generator (102) and the coupling means are positioned above the upstream level.

Description

Hydroelectric plant of very low fall

The present invention relates to a hydroelectric plant of very low fall.

A very low hydro power plant is a plant that uses a useful waterfall of 0.5m to 2.5m to generate electrical energy.

In the remainder of the description, the term upstream and the downstream term are taken with reference to the hydroelectric plant.

A hydroelectric power plant is known which is installed in the bed of a waterway whose bottom includes, at this location, a difference in height making it possible to create a difference between the upstream level of the waterway and the downstream level of the waterway. waterway. The bottom of the waterway thus comprises a substantially horizontal upstream portion, a substantially horizontal downstream portion and a sloped intermediate portion which follows the drop of the bottom of the waterway and which connects the upstream portion to the downstream portion.

This hydroelectric plant comprises a closed pipe which follows the bottom of the waterway, that is to say that the pipe comprises a first substantially horizontal portion corresponding to said upstream portion, a second substantially horizontal portion corresponding to said downstream portion and a third sloping portion corresponding to said intermediate portion. In the first part is installed a propeller turbine. The turbine is mounted on a horizontal axis which extends towards the downstream of the waterway and which crosses the wall of the pipe at its third portion. The axis then connects to an electric generator that converts the mechanical energy of rotation of the turbine into electrical energy. The electrical energy is then recovered and sent to a conventional distribution network or used on site.

The electric generator is placed on a platform whose altitude is between the upstream level of water and the downstream level of water. Because of the design of the pipe, the water is forced to pass through the pipe and thus the generator is still out of the water. By cons, the passage of the axis through the wall of the pipe requires the establishment of a rotating seal and sealed which is expensive and requires maintenance to verify its proper operation and its sealing.

The use of such a seal is not compatible with a hydroelectric plant whose implementation and maintenance costs must be low.

An object of the present invention is to provide a hydroelectric plant which does not have the disadvantages of the prior art and which in particular does not use expensive technical components.

For this purpose, there is proposed a hydroelectric plant of very low fall, the fall extending between the upstream level and the downstream level of a waterway, the hydroelectric plant comprising:

a fixed load-bearing structure with respect to the banks of the waterway;

a chassis mounted on the supporting structure, and

at least one electrical power generation assembly fixed to said chassis, each current generation assembly comprising:

means for channeling the fall;

an electric generator;

a drive means disposed inside the channeling means and driven in rotation by the water of the chute; and a rotation shaft substantially parallel to the current lines of the chute, the first end of which is integral with the drive means and the second end of which comprises means for coupling with the electric generator; the hydroelectric plant being such that the second end extends above the upstream level and the electric generator and the coupling means are disposed above the upstream level.

According to a particular embodiment, the hydroelectric plant of very low drop includes displacement means adapted to move the frame vertically relative to the bearing structure.

Advantageously, the displacement means comprise integral racks of the supporting structure, pinions which mesh with the racks, a transmission shaft on which are mounted the pinions and a geared motor integral with the chassis and adapted to drive the shaft in rotation. of transmission.

Advantageously, the chassis comprises detection means adapted to detect the water level of the upstream level and control means adapted to control the displacement means as a function of the height thus detected.

Advantageously, the detection means comprise a first water detector positioned in the vicinity of the upper part of the inlet of the channeling means and a second water detector positioned at a height between that of the first detector and that of the generator. electrical and coupling means.

Advantageously, the frame is provided with a filtering grid disposed at the inlet of the or each channeling means.

Advantageously, the hydroelectric plant of very low fall comprises a retaining device which extends from the bottom of the waterway to come flush with the inlet of the or each channeling means.

Advantageously, the retaining device is adapted to be positioned in a first position in which it completely closes the waterway upstream of the chute or in a second position in which it partially closes the waterway upstream of the fall.

Advantageously, the retaining device comprises an upper portion secured to the frame and a lower portion resting on the bottom of the waterway. Advantageously, when the retaining device is in the first position, the lower edge of the upper part and the upper edge of the lower part overlap. Advantageously, when the retaining device is in the second position, the lower edge of the upper part and the upper edge of the lower part are distant from each other.

Advantageously, the hydroelectric plant of very low drop comprises securing means provided to allow to secure the upper part and the lower part.

Advantageously, the chute channeling means comprise a water chamber fed with water from the upstream level and a water guide in substantially cylindrical form fed at the outlet of the water chamber. The characteristics of the invention mentioned above. above and others will appear more clearly on reading the following description of an exemplary embodiment, said description being given in relation to the accompanying drawings, in which: FIG. 1 represents a hydroelectric plant of very low fall according to the invention; FIG. 2 is a side view of the hydroelectric plant of very low drop in a first operating position; FIG. 3 is a side view of the hydroelectric plant of very low fall in a second operating position; and FIG. 4 is an enlargement of the hydroelectric plant of very low fall according to the invention.

Fig. 1 shows a very low-drop hydroelectric plant 100 which, in the embodiment shown, is provided with two sets of electric power generation 122a and 122b and is disposed in the bed of a waterway. Fig. 2 shows a side view of the hydroelectric plant 100 in operating position in a waterway. The fall extends between the upstream level referenced 210 and the downstream level referenced 212 of the waterway and the number or the dimension of the electrical energy generation assemblies 122a and 122b can be modified according to the width of the waterway or the amount of electrical energy to be supplied.

In a particular embodiment, the waterway is constituted by the channel of an existing water mill and for which no civil engineering modification is necessary. Indeed, this channel is intended to receive a paddle wheel and the central hydroelectric 100 according to the invention is perfectly adapted to replace this impeller.

The hydroelectric plant of very low fall 100 includes:

a supporting structure 104a, 104b; a chassis 130 mounted on the supporting structure 104a, 104b;

at least one electrical energy generation assembly 122a, 122b fixed to the chassis 130.

The supporting structure is fixed relative to the banks of the waterway and comprises two rails 104a and 104b. Each rail 104a, 104b is attached to one of the banks of the waterway so that the hydroelectric plant 100 occupies the entire width of the waterway. Each rail 104a, 104b extends vertically from the bottom of the waterway to the top of the upstream level. Each rail 104a, 104b here takes the form of a U in which the frame 130 is positioned and can optionally slide as explained below. Each current generating assembly 122a, 122b comprises:

channeling means 1 12, 114 of the chute;

an electric generator 102;

a drive means 118 disposed inside the channeling means 112, 114 and rotated by the water of the chute; and a rotation shaft 120a, 120b substantially parallel to the current lines of the chute, the first end of which is integral with the drive means 1 18 and the second end of which comprises coupling means 204, 206, 208 with the generator electrical 102.

In the embodiment of the invention shown in FIG. 2, the channeling means 112, 114 comprise a water chamber 112 fed with water from the upstream level 212 and a water guide 114 of substantially cylindrical shape and supplied with water leaving the water chamber 112.

The electric generator 102 is conventionally in the form of a cylinder which has a pulley 206 at its inlet and which, at the output, delivers an electrical energy that can supply a distribution circuit.

Each drive means 118 here takes the form of a propeller which is attached to the rotation shaft 120a, 120b corresponding thereto, but it can take any form as long as its motion generated by the waterfall is a rotation around it of an axis substantially parallel to the current lines of the chute. The propeller 1 18 is positioned inside the water guide 1 14 whose axis is parallel to the flow lines of the chute. The current lines between the upstream level 210 and the downstream level 212 are represented by the arrow 202 in FIG. 2 and the current lines of the fall are represented by the portion 202a of the reference 202.

The coupling means 204, 206, 208 here take the form of a pulley 204 mounted on the rotation shaft 120a, 120b, the pulley 206 mounted on the electric generator 102 and a belt 208 mounted between the two pulleys 204, 206. Thus, the rotation of the drive means 1 18 causes the rotation of the two pulleys 204 and 206 and therefore the generation of electrical energy by the electric generator 102.

The second end of the rotation shaft 120a, 120b extends above the upstream level 210 and the electric generator 102 and the coupling means 204, 206, 208 are disposed above the upstream level. The rotation shaft 120a, 120b is guided by two bearings 214 and 216 which are respectively disposed at the second end and above the upstream level 210.

This particular arrangement prevents that the fragile elements such as, in particular, the coupling means 204, 206 and 208, the bearings 214 and 216 and the electric generator 102, are at a lower level than the upstream level. Thus none of these elements dipped in the water of the waterway and it is not necessary that these elements are sealed, which reduces the cost of the installation of the hydroelectric plant 100 and the cost of its maintenance.

The channeling means and, in particular, the water chamber 1 12 are traversed by the rotation shaft 120a, 120b. Indeed, the opening of the water chamber 1 12, that is to say the inlet of the channeling means 1 12, 1 14, faces the upstream level 210, that is to say in the plane passing through the two rails 104a and 104b, and the upper part of the water chamber 1 12 is provided with a grid 1 16a (FIG 4), 1 16b which, in the embodiment described here, is provided with an orifice through which the rotation shaft 120a, 120b passes. Each grid 1 16a, 1 16b allows the passage of upstream water while preventing the passage of objects such as, for example, debris. The water level of the waterway is variable over time, it is therefore preferable to provide displacement means 124a, 124b, 126a, 126b, 428, 430 adapted to vertically move the frame 130 relative to the supporting structure 104a, 104b. Fig. 2 shows the hydroelectric plant 100 in a first operating position in which the water level is low while FIG. 3 is a side view of the hydroelectric plant of very low fall in a second operating position in which the water level is high. In the case of FIG. 3, the upstream level is referenced 310 and the downstream level is referenced 312 and the current lines between the upstream level 310 and the downstream level 312 are represented by the arrow 302.

Fig. 4 represents an enlargement of the hydroelectric plant 100 seen from the downstream side. In the embodiment of the invention shown, the displacement means 124a, 124b, 126a, 126b, 428 and 430 comprise two racks 124a and 124b, two pinions 126a and 126b, a transmission shaft 430 and a geared motor 428. .

Each rack is secured to one of the rails 104a, 104b and extends vertically. The transmission shaft 430 extends between the two rails 104a and 104b and at each of these ends is fixed one of the pinions 126a or 126b. Each pinion 126a, 126b meshes with one of the racks 124a or 124b. The geared motor 428 is integral with the frame 130 and controls the rotation of the transmission shaft 430 and therefore the pinions 126a, 126b and thus the displacement of the frame 130 along the rails 104a and 104b.

To automate the raising or lowering of the frame 130 along the rails 104a and 104b, it is advantageous to provide that the frame 130 is provided with detection means adapted to detect the water level of the upstream level and adapted control means for controlling the displacement means 124a, 124b, 126a, 126b, 428, 430 as a function of the height thus detected.

In a particular embodiment of the invention, the detection means comprise a first water detector positioned in the vicinity of the upper part of the inlet of the channeling means 1 12, 114 and a second water detector positioned at a height between that of the first detector and that of the electric generator 102 and coupling means 204, 206, 208. According to a particular embodiment, the second detector is positioned a few centimeters higher than the first detector. In other words, the first water detector is arranged to determine when the upstream level 210 drops too much to no longer properly feed the water drop and thus causing a decrease in production energy. And the second water detector is arranged to determine when the upstream level 210 rises too much at the risk of immersing the fragile elements.

The control means may take the form of a control unit receiving the indications of presence or absence of water from each of the water detectors and emitting an upward or downward order of movement towards the means of control. displacement and, in particular, to the geared motor 428.

To prevent the introduction of floating debris inside the pipe means 1 12, 1 14 and thus prevent the deterioration of the drive means 1 18, the frame 130 is provided with a filtering grid 132 arranged at the entry of each channeling means 1 12, 114.

When the floating debris clutches the filtering grid 132, appropriate means detect this space and the frame 130 is raised to a height such that each set of electrical energy generation 122a, 122b is found out of the water, which allows the floating debris to pass under the electrical energy generation assemblies 122a and 122b. After the evacuation of the debris, the electrical energy generation assemblies 122a and 122b are repositioned in the water.

To create the waterfall, a retainer 106, 108 is disposed across the waterway. This retainer 106, 108 prevents the passage of water, creating a dam that the water from the upstream must overcome to reach the downstream. The retaining device 108, 106 thus extends from the bottom of the waterway to come flush with the inlet of each channeling means 1 12, 1 14.

In a particular mode of operation, the retaining device 106, 108 may be in a first position in which it completely closes the waterway or in a second position in which it partially closes the waterway upstream of the fall to allow free passage of part of the upstream flow downstream and allow the free passage of fish. The retaining device 106, 108 is thus adapted to be positioned in the first position or in the second position. For this purpose, the retaining device comprises an upper portion 108 integral with the frame 130 and a lower portion 106 resting on the bottom of the waterway. The upper part 108 and the lower part 106 take, here, the form of plate extending over the entire width of the waterway. The upper part 108 thus extends the lower part of the inlet of the channeling means 112 and 1 14 downwards and the lower part 106 thus extends from the bottom part of the waterway upwards.

When the retainer 106, 108 is in the first position, that is to say it completely closes the waterway upstream of the chute, the lower edge of the upper portion 108 and the upper edge of the the lower part 106 overlap, thus preventing any passage of water outside the channeling means 112 and 114. This first position is particularly advantageous when the flow rate of the waterway becomes low. Indeed, it is, then, necessary to guarantee a minimum flow passage at the hydroelectric plant 100, and the setting in position of the retaining device 106, 108 in the first position makes it possible to block the upstream water which must back up to overcome the dam thus created and, thus, satisfactorily feed the hydroelectric plant 100.

When the retainer 106, 108 is in the second position, that is to say it partially closes the waterway upstream of the chute, the lower edge of the upper portion 108 and the upper edge of the the lower part 106 are distant from each other. This positioning creates a free space 1 10 through which a portion of the water can flow. This flow is shown in FIG. 1 and FIG. 3 by the reference 304. This second position is the consequence of the lifting of the frame 130 when the level of the waterway increases, as for example, in times of flood. At the bottom of the waterway rests particles of earth or sand which are entrained by the upstream water flow and which agglutinate against the lower part 106. In order to allow the removal of the bottom portion 106, securing means are provided to allow the lower part 106 and the upper part 108 to be secured. These securing means may, for example, take the form of hooks secured to the upper part 108 coming into holes made in the lower part 106 When the lower part 106 and the upper part 108 are integral, it is then sufficient to raise the frame 130 and thus the upper part 108 to raise at the same time the lower part 106.

According to the particular embodiment of the hydraulic unit 100 which has been described above, the hydraulic unit 100 can therefore take three characteristic positions. The first position corresponds to the entire filling of the waterway. The second position corresponds to the partial closure of the waterway. A third position corresponds to the stop of the hydraulic unit 100, for example, for maintenance reasons. In this third position, the chassis 130 is lifted so that all the upstream water flow passes below the upper portion 108 without passing into the channeling means 1 12 and 1 14.

Of course, the present invention is not limited to the examples and embodiments described and shown, but it is capable of many variants accessible to those skilled in the art.

Claims

1) Hydroelectric plant of very low fall (100), the fall extending between the upstream level and the downstream level of a waterway, the hydroelectric generating station (100) comprising:

a supporting structure (104a, 104b) fixed with respect to the banks of the waterway; a chassis (130) mounted on the supporting structure (104a, 104b) and at least one electrical energy generating assembly (122a, 122b) attached to said chassis (130), each current generating assembly (122a, 122b); ) including:

channeling means (112, 114) of the chute; an electric generator (102);

a drive means (1 18) disposed inside the channeling means (112, 114) and rotated by the water of the chute; a rotation shaft (120a, 120b) substantially parallel to the drop current lines, the first end of which is integral with the drive means (118) and the second end of which comprises coupling means (204, 206, 208); ) with the electric generator (102) and whose second end extends above the upstream level; and the electric generator (102) and the coupling means (204, 206, 208) being arranged above the upstream level,

The hydroelectric plant of very low fall (100) being characterized in that it comprises displacement means (124a, 124b, 126a, 126b, 428, 430) adapted to vertically move said frame (130) relative to said bearing structure (104a, 104b).

2) hydroelectric plant of very low fall (100) according to claim 1, characterized in that the displacement means (124a, 124b, 126a, 126b, 428, 430) comprise racks (124a, 124b) integral with the bearing structure (104a, 104b), pinions (126a, 126b) which mesh with the racks (124a, 124b), a transmission shaft (430) on which are mounted the pinions (126a, 126b) and a geared motor (428). secured to the frame (130) and adapted to rotate the transmission shaft (430). 3) hydroelectric plant of very low fall (100) according to one of claims 1 or 2, characterized in that the frame (130) comprises detection means adapted to detect the water level of the upstream level and adapted control means for controlling the displacement means (124a, 124b, 126a, 126b, 428, 430) as a function of the height thus detected.

4) hydroelectric plant of very low fall (100) according to claim 3, characterized in that the detection means comprises a first water detector positioned in the vicinity of the upper part of the inlet of the channeling means (112, 1 14) and a second water detector positioned at a height between that of the first detector and that of the electric generator (102) and coupling means (204, 206, 208).

5) hydroelectric plant of very low fall (100) according to one of claims 1 to 4, characterized in that the frame (130) is provided with a filtering grid (132) disposed at the inlet of the or each means of channelization (112, 1 14).

6) hydroelectric plant of very low fall (100) according to one of the claims

1 or 5, characterized in that it comprises a retaining device (108, 106) which extends from the bottom of the waterway until it comes flush with the inlet of the or each channeling means ( 1 12, 1 14).

7) hydroelectric plant of very low fall (100) according to claim 6, characterized in that the retaining device (106, 108) is adapted to be positioned in a first position in which, it completely closes the waterway in upstream of the fall or in a second position in which it partially closes the waterway upstream of the fall.

8) hydroelectric plant of very low fall (100) according to one of claims 6 or 7, characterized in that the retaining device comprises an upper part

(108) secured to the frame (130) and a lower portion (106) resting on the bottom of the waterway. 9) hydroelectric plant of very low fall (100) according to claim 8, characterized in that, when the retainer is in the first position, the lower edge of the upper part (108) and the upper edge of the lower part (106) overlap.

10) hydroelectric plant of very low fall (100) according to one of the claims

8 or 9, characterized in that, when the retaining device is in the second position, the lower edge of the upper part (108) and the upper edge of the lower part (106) are distant from each other .

11) hydroelectric plant of very low fall (100) according to one of claims 8 or 10, characterized in that it comprises securing means provided to allow to secure the upper portion (108) and the lower portion (106).

12) hydroelectric plant of very low fall (100) according to one of the preceding claims, characterized in that the channeling means (112, 114) of the chute comprises a water chamber (112) supplied with water from the level upstream and a water guide (114) in substantially cylindrical form fed at the outlet of the water chamber (1 14).