RU2321743C1 - Birotatory generator - Google Patents

Abstract

FIELD: electrical engineering.

SUBSTANCE: birotatory electric generator comprises at least one fastening unit, outer rotor with the birotatory hydraulic turbine and exciting magnets, and stator provided with the exciting winding and electric plug. The inner space of the stator and outer rotor are sealed with permeable baffles. The driven magnets of two face clutches are arranged from both sides of the baffles. The top intermediate rotor with driven magnets, top inner shaft, cylindrical magnetic clutch with driven magnets of the cylindrical magnetic clutch on the outer rotor and driving magnets of the cylindrical magnetic clutch on the top intermediate rotor are mounted in bearings concentrically to the outer rotor. The bearings are mounted inside the rotor. The driving magnets of the face magnetic clutches are opposite to the permeable baffles within the space of the outer rotor. The driven magnets of the face magnetic clutches are opposite to the permeable baffles within the space of the stator. The driven magnets of the inner face magnetic clutch are mounted on the bottom inner shaft. The driven magnets of the outer magnetic clutch are mounted on the bottom intermediate shaft. The exciting magnets are mounted on the bottom inner shaft.

EFFECT: enhanced power.

6 cl, 2 dwg

Description

The invention relates to electric machines. Specifically, the invention is intended for a downhole power generator and a downhole telemetry system transmitter. The generator converts the energy of the flushing fluid into electrical energy, which is necessary to power the downhole navigation and geophysical instruments during drilling and the transmitter of the electromagnetic communication channel. For the telemetry system to work at great depths, an increase in the power of the transmitting device to 1 kW or more is required. To get more power with small dimensions of the generator is very problematic

A known alternator for powering the telemetric system in the process of drilling small diameter wells, including a fixed internal stator with a collector and an external rotor mounted on the drive shaft, equipped with electromagnets (RF patent No. 2060383, MKP ЕВВ 47/022, 47/00, priority from 21.02 .92 g.). The lubrication system is a cavity between the rotor and the stator, filled with lubricating fluid.

A self-contained turbine unit (electric generator) is also intended for supplying electric energy to the telemetry system, containing a hydraulic turbine driven by a wash fluid stream, an oil-filled stator filled with an epoxy compound, and a rotor of an alternating current generator with permanent magnets located on the same shaft with a hydraulic turbine ( Molchanov A.A., Siraev A.X., “Borehole autonomous systems with magnetic recording”, M., Nedra, 1979, pp. 102-103).

This generator consists of a stator located inside the unit and a six-pole annular magnetic rotor made from the outside. The rotor is also a casing for the working blades of a three-stage hydraulic turbine. In front of each stage of the working blades of the hydraulic turbine, in turn, there are three stages of guide vanes assembled on the outer casing, which increases the diameter of the device. To prevent the flushing fluid from entering the generator and the bearing units, sealing devices are installed, the internal cavity of the generator is filled with transformer oil.

Due to the fact that the generator operates in the temperature range from -40 to + 130 ° С, at drilling depths up to 3500 m and more, and the oil volume changes with temperature, a compensator for pressure and thermal expansion of the lubricating fluid (oil) is introduced. The compensator for pressure and thermal expansion of the lubricating fluid is made inside the inlet fairing of the generator. It consists of two thin profile plates, one of which is convex and the other is concave. The compensator for pressure and thermal expansion of the lubricating fluid is designed to compensate for changes in the volume of oil in the oil-filled cavity of the generator under operating conditions with increasing temperature, as well as equalizing the pressure inside and outside the generator.

The disadvantages of this generator are:

- low reliability

- small resource

- large dimensions and mass of the device,

- the complexity of the design.

These shortcomings are caused, first of all, by the fact that a multistage turbine with guide vanes is used as a drive. The use of a hydraulic turbine with guide vanes as a drive places high demands on the quality of cleaning the washing liquid from fractions of drill cuttings and foreign objects, the ingress of which into the gap between the working and guide vanes of the hydraulic turbine can cause it to stop (jamming). The presence of guiding devices of a hydraulic turbine increases the diametrical dimension of the electric generator, which is undesirable when drilling wells of relatively small diameter.

The second design flaw is the complexity and unreliability of the pressure compensator and thermal expansion of the lubricating fluid. Due to the elasticity of the walls of the compensator, the pressure of the lubricating fluid is always less than the pressure of the environment. This can result in flushing fluid entering the generator’s lubrication system and in the wear of bearings, seals and other parts.

Also known generator according to US Pat. RF №2173925, the main feature of which can be considered a lubrication system. The lubrication system of this generator contains a filling device at its front end, a cavity between the external rotor and the stator filled with a lubricating fluid, and a pressure compensator and thermal expansion of the lubricating fluid located on the side of the generator mounting device, made in the form of a piston mounted axially displacement and seals mounted inside the piston with the possibility of axial displacement with it. The disadvantage of this device is the difficulty of filling the system with lubricating fluid and a low seal life.

Known power generator telemetry systems according to St. RF №34638.

This electric generator contains a filling device in its front part, a cavity between the external rotor and the stator filled with a lubricating fluid, and a compensator for pressure and thermal expansion of the lubricating fluid located on the side of the generator mounting device, made in the form of a piston mounted inside the rotor with axial movement , and the seal, installed, in turn, inside the piston with the possibility of axial movement with it, the piston is made with the possibility of drainage lubricating the fluid in the fully tucked position to the gap between the rotor and the alternator mounting assembly.

The disadvantage of this lubrication system is that due to the combination of the functions of the compensator and the seal, their life is reduced.

Known generator for St. RF №13123, which contains a rotor with a turbine, a stator, a mounting unit and a reservoir for the reserve supply of lubricating fluid, made in the form of a cup made in the front of the generator with a spring-loaded piston installed inside and a refueling device. The generator and turbine are significantly distant from each other in the axial direction and are separated by a magnetic coupling, which increases the dimensions of the generator and reduces the reliability of the lubricant.

A known generator according to the patent of the Russian Federation for invention No. 2264537, a prototype comprising a housing with field windings, a mount, a rotor with a shaft, magnets and a turbine mounted through bearings in the housing, and a reservoir for a reserve supply of lubricating fluid in the form of a cup made in front generator with a spring-loaded piston installed inside and a refueling device, characterized in that at least one front bearing is mounted in a sleeve that is centered in the protruding part of the housing, closed on the other Torons axis fixed against rotation and having an annular groove for windings, and the cylindrical projection in the inner bore of which is mounted on at least one rear bearing and the inside shaft provided with a through axial aperture. An adjustment washer is installed between the front bearing and the rotor. Field windings are installed in the housing and are fixed with pins against bias. The spring is partially placed inside the piston. The filling device is made in the form of a valve installed in the stem channel, closed by a plug.

Disadvantages - insufficient power of the generator with limited diametrical dimensions.

The tasks of its creation are to increase power while reducing the diametrical dimensions and weight of the generator.

The solution to this problem was achieved due to the fact that the biotic generator containing at least one attachment point, an external rotor with a biotic turbo-turbine and field magnets, a stator on which a field coil and an electrical connector are installed, the internal cavities of the stator and external rotor are sealed magnetically permeable baffles, on both sides of which there are driven magnets of two mechanical couplings, while the upper part is mounted concentrically to the external rotor on bearings made inside it the intermediate rotor with driven magnets, the upper inner shaft, the cylindrical magnetic coupling with the driven magnets of the cylindrical magnetic coupling on the outer rotor and the driving magnets of the cylindrical magnetic coupling on the upper intermediate rotor, the leading magnets of the end magnetic couplings are installed against magnetically permeable partitions in the inner cavity of the outer rotor, the driven magnets mechanical magnetic couplings are installed against magnetically permeable partitions in the inner cavity of the stator, while the driven magnets of the inner s end face magnetic coupling mounted on the lower inner shaft, and the driven magnets outer magnetic couplings mounted on the lower intermediate shaft and the inner shaft at the lower set of excitation magnets. Hydroturbines are installed side by side in front of the generator. The wires from the winding to the electrical connector pass through the holes made in the stator. The inner cavity of the magnetic coupling is filled with a lubricating fluid, and the inner cavity of the field coil and field magnets is filled with a compensating fluid. The lubricant filling hole is made at the top, and the electrical connector is at the bottom. The electrical connector is coaxial.

The proposed technical solution has novelty, inventive step and industrial applicability, i.e. all the criteria of the invention. The novelty is confirmed by patent research, the inventive step - a new layout of the generator. For the manufacture of all nodes of the electric generator, scarce materials and newly developed technologies are not required, which guarantees industrial applicability.

The invention is illustrated in the drawings, where

figure 1 shows the assembly drawing of a biotational generator,

figure 2 shows the arrangement of hydraulic turbines.

A biotic generator designed to power the downhole equipment is installed in the drill pipe string or in the casing and contains at least one mounting device for the generator 1 on the stator 2. In the mounting device of the electric generator 1, holes B are made for drilling fluid passage.

The biotic generator contains an external rotor 3 with a rear hydraulic turbine 4 and an internal rotor 5 with a front hydraulic turbine 6, i.e., a hydraulic turbine is made of a two-stage biotic. The front hydroturbine 6 has obliquely mounted flat blades mounted at an angle of 20 ... 45 °, and the blades of the hydroturbine 4 are made profiled in order to more effectively operate the pressure drop across the hydroturbines, because the execution of both turbines the same would not allow working out the difference in the second downstream, i.e. rear turbine 4.

The stator 2 has an electrical connector 7 at the bottom, and an excitation winding 8 is installed inside the stator 2.

A ring magnetic coupling 9 is made concentrically to the external rotor 3 inside of it in front of the birotational generator, on both sides of which are driven magnets of the magnetic ring coupling 10 and driving magnets of the magnetic ring coupling 11. The generator has two non-magnetic partitions 12 and 13 that separate the external rotor 3 from the stator 2 and create the inner cavity of the outer rotor B and the inner cavity of the stator E. On both sides of the non-magnetic partitions 12 and 13 are magnets of two end magnetic couplings, namely: and external, specifically driven magnets of the internal and external couplings, respectively 14 and 15. Magnets 14 are mounted on the upper shaft 16, and magnets 15 are mounted on the upper intermediate shaft 17, which is mounted on the bearings 18 and 19. The cavity B is filled with a lubricating fluid. The lubricant of the cavity B is filled with lubricating fluid through the channel G, which was closed during operation with the screw 20. Inside the stator 2, at its upper end near the non-magnetic partition 12, the driven magnets of the internal and external mechanical couplings 21 and 22, respectively, are installed. Excitation magnets 24 are installed on the lower shaft 23, and an excitation winding is installed on the lower intermediate shaft 25. The lower shaft 23 is installed in the bearing 26, and the intermediate shaft 24 on the bearing 27. The lower shaft 23 has a thrust collar 28, under which the collector rings 29 are installed with which the current collectors 30 are in contact. The wires 31 through the holes D are connected to the electrical connector 7 and sealed by the compound 32. To fill the cavity E with compensating liquid, there is a hole in the stator of the generator 2, closed by a plug 33.

Hydroturbines 4 and 6 are installed side by side, at a distance of 2 mm ... 5 mm from each other in the front of the generator for more complete operation of the pressure drop due to the profiling of the turbine blades 4 and 6 with different angles of installation of the blades. Hydroturbine 6 is simultaneously a nozzle apparatus for hydroturbine 4 (figure 3). This allows you to abandon the use of nozzle devices, which will simplify the assembly of the generator and reduce its diametrical dimensions and weight of the generator.

The internal cavity of the autonomous generator B is filled with a lubricating fluid. The hole Г for filling the inner cavity of the generator Г with lubricating fluid is made in the upper part of the inner rotor 5 and is closed by a screw 19.

The cavity E, in which the field coil 8 and the field magnets 23 are located, is filled with a compensating liquid. The compensating liquid has a specific volume expansion coefficient equal to the specific volume expansion coefficient of the metal from which the stator 2 is made, while the compensating liquid does not have to have lubricating properties.

On the stator 2 in the lower part there is a filling hole for the compensating liquid, closed by a screw 33.

When the generator is operating, the drilling fluid passes through the hydraulic turbines 6 and 4, which begin to rotate with the rotor 3 and the upper inner shaft 16 in different directions. The driving magnets of the annular magnetic coupling 10 rotate and create magnetic fields that drive the driven magnets of the annular magnetic coupling 10, which rotate at angular speeds corresponding to the rotational speed of the outer rotor 3.

In this case, the first flow turbine 6 will act as a nozzle apparatus for the second flow turbine 4. This will simplify the assembly of the generator, abandon the use of guide vanes and increase the efficiency and power of the turbine. It also became possible to significantly reduce the diametrical dimensions of the generator or increase its power by about 2 times with the same dimensions and weight. This will allow the design of downhole tools for small diameter drill and casing. The use of wires for the transmission of electrical energy, located in the holes E of the stator 2, will allow you to output significant power using sliding current collectors 30. A generator with a downhole telemetry system downhole device can be installed in a drill or casing assembled from pipes up to 10 ... 12 m long , i.e. the length limit is not critical, unlike the diameter limit. The diameter of the layout: generator - downhole tool is strictly limited by the diameter of the string. Electricity is transmitted through wires 31 from the field winding 8 to the electrical connector 7. It is preferable to make the electrical connector 7 coaxial, this will eliminate the angular orientation of the electric generator inside the drill string or casing when it is docked with the downhole tool (Fig. 1 ... 2 downhole tool not shown).

The application of the invention allowed the following.

1. Significantly reduce the diametrical dimensions and weight of the birobotative generator through the use of a biotative turbine and increase its length by the length of the magnetic coupling.

2. To increase the power and voltage at the electrical terminals of the generator through the use of a biotic turbine.

3. Significantly increase the service life of the supports due to the use of multi-support schemes, reduce the diameter of two seals to the minimum possible, ie to the shaft diameter and minimize the sliding speed of the upper seal on the shaft relative to the shaft to almost zero.

4. To reduce the imbalance of the rotor of the birotative generator by reducing their diameter by 1.5 ... 2.0 times.

5. To increase the reliability of sealing the cavity of the birobative generator by separating the oil cavity B from the cavity with compensating liquid E with a volume coefficient of thermal expansion equal to the volume coefficient of thermal expansion of the metal from which the stator is made, and rejection of the temperature expansion compensator, without which the generators in the face usually not applicable.

6. To simplify the design of the birotative generator due to the rejection of the use of guide vanes of the turbine and the maximum simplification of the seal design.

7. To simplify the assembly and disassembly of the biotic generator due to its modular design and the use of a coaxial electrical connector.

8. Improve the maintainability of the birotative generator due to the extremely simple design, the minimum number of parts and the simple configuration of all parts.

Claims (6)

1. A rotational generator containing at least one attachment point, an external rotor with a biotative hydraulic turbine and field magnets, a stator on which a field coil and an electrical connector are installed, the internal cavities of the stator and the external rotor are sealed with magnetically permeable partitions, on both sides of which there are driven magnets of two end couplings, while concentrically to the outer rotor, on the bearings made inside it, an upper intermediate rotor with driven magnets is installed, the upper inside the drive shaft, a cylindrical magnetic coupling with driven magnets of the cylindrical magnetic coupling on the outer rotor and the driving magnets of the cylindrical magnetic coupling on the upper intermediate rotor, the driving magnets of the end magnetic couplings are installed against the tight magnetically permeable partitions in the inner cavity of the outer rotor, the driven magnets of the end magnetic couplings are installed against the tight magnetically permeable partitions in the inner cavity of the stator, while the driven magnets of the internal mechanical coupling They are mounted on the lower inner shaft, and the driven magnets of the external magnetic coupling are mounted on the lower intermediate shaft, and the field magnets are mounted on the lower inner shaft. 2. The biirotational generator according to claim 1, characterized in that the turbines are mounted side by side in front of the generator. 3. The biirotational generator according to claim 1 or 2, characterized in that the wires from the winding to the electrical connector pass through holes made in the stator. 4. The biotic generator according to claim 1 or 2, characterized in that the internal cavity of the magnetic coupling is filled with a lubricating fluid, and the internal cavity of the field coil and field magnets is filled with a compensating liquid. 5. The biirotational generator according to claim 1 or 2, characterized in that the opening for filling the lubricating fluid is made from above, and the electrical connector is from below. 6. Biirotational generator according to claim 5, characterized in that the electrical connector is made coaxial.

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