Wind turbine generator with Multi row cantilever stud supported curved magnets on single rotor plate sandwiched between multi row radial and axial coil plates

Abstract

Axial flux generators are often preferred over Radial flux generators for use in wind turbines for its efficiency and smooth operation. However, arranging multiple layers of rotor plates in axial flux machines makes the machine extremely heavy owing to use of multiple rotor plates. The present invention demonstrates use of single rotor plate to support multiple row cantilever magnets supported by studs, generating flux in the radial direction. The arrangement is sandwiched between multi row axial and radial curved coil plates. This arrangement reduces weight of the generator manifolds and increases efficiency significantly. The size of the generator turns very compact. Copper coil sets are curved to be molded with resin and the coil plates are positioned concentric to each other. The resin in liquid form is reinforced with carbon nano tube uniformly distributed for enhanced strength in curved condition.

Specification

Description:COMPLETE SPECIFICATION: DESCRIPTION OF THE INVENTION

TITLE: Wind turbine generator with Multi row cantilever stud supported curved magnets on single rotor plate sandwiched between multi row radial and axial coil plates
PRIOR ART:02162150
Patent US 5625241 highlights positioning of various magnets over a carousel in different configuration. The magnets are mounted over several arms positioned at equal angles across the circle. Each arm is equipped with a host of magnets which forms the rotor plate. The coils are mounted sidewise. Patent US 6864614B2 hosts a circumferential structure holding the permanent magnets and the coils are positioned on arms placed uniformly across the circle. Patent US 9787851B2 also presents permanent magnets positioned circumferentially around an axis which forms the rotor plate.


DRAWBACKS IN THE PRIOR ART:
• Magnets are arranged over different arms leading to increase in weight of the structure. The arrangement is not purely axial or radial. Magnets positioned with adhesive are not permanent joints and are vulnerable to be dislocated under fatigue load. The structure described the prior art has limitations in the number of magnets that can be positioned in one arm.
• The coils are not resin moulded and hence cannot be regarded as safe permanent structure. Coils positioned independently over separate arms holds key challenges in electrical connections.
• No scope is provided for scaling up the power production keeping overall size of the generator constant.
• Circuit arrangement for joining coils in several arms is not explained.
• Ferro magnets positioned in sectors across the circle have very limited ability of generating strong flux for producing enough power.
EFFORTS OR SOLUTIONS TO DRAWBACKS:
• In the present structure, curved magnets are designed so as to facilitate its placement on a single continuous rotor plate/disc. There is scope of adding several magnet rows concentrically over the same plate owing to formation of a compact structure with less weight.
• The coils are resin moulded in order to make it a single integral unit. This enhances the life of the coil plate manifolds. All the coil plates are positioned over a single base plate. The resin moulding solution is prepared by mixing it with 3% volume of carbon nano tube particles enhancing significantly the strength of the structure.
• There is significant scope to scale up the structure for more power output without increasing the overall size of the structure. Coil plates are stacked axially and also radially in this arrangement for more power output by increasing the number of coils in the design.
• Coil plate connection has been uniquely done to take care of a fail safe redundant design. In the event of failure of a single coil plate, provisions are kept in the design to connect the remaining coil plate for possible power output.
• Neodymium magnets are used over ferro magnets with much enhanced guass value, the architechture of which has been further improved as the magnets are designed curved to improve flux line exchanges with the coils.




DETAIL DESCRIPTION OF THE INVENTION:
The present invention is about a method of creating a wind turbine generator wherein curved neodyminium magnets (1) shown in Fig. 1(A) is positioned along the circumference of a circle. Several such rows can be positioned concentrically on the same magnet mounting plate (2) as shown in Fig. 1(B). Thus a single magnet mounting plate can be used to hold several rows of magnets and thereby saving weight of the generator manifolds. The magnet mounting plate is fitted with a shaft (3) as shown in Fig. 1(A) and Fig. 1(B).
The coil plates (5), (6), (7) & (8) as shown in Fig. 2 are positioned in the base plate of the generator. The coil plates are having sectorial slots along the circumference of a circle which is used to position the coil plates in slots provided in the base plate. The above said magnet rows would be positioned in the space provided between two coil plates. Thus the generator would consist of a series of magnet and coil plates. The total assembly of radial flux based magnet and coil plates is shown in Fig. 3.
The coil plates can also be stacked vertically along the axis as shown in Fig. 4(B). Fig. 4(A) shows the circular resin moulding (10) and with coils (9) positioned along the circumference of the circle. In order to increase the power output from the generator, number of turns in the coils are to be increased. To increase the number of turns, the width of the coil will also increase along with the length. If the width of the coil increases, suitable number of coils required to fulfill the power ratio could not be accommodated along the circumference. Thus, in an attempt to derive more power output from a limited space, vertical stacking of the coil plate has been envisaged and attempted.
The curved magnets (1) are positioned with poles alternated as shown in Fig. 5. The magnets are positioned with a special technique with studs (11) in between two magnets in along the circumference of the circle. The studs have tap holes on either side. The stud is first positioned on the magnet plate by fixing a screw from the bottom. The magnets are then positioned side wise. A screw is then mounted on the top of the stud, the face of which holds the magnets steady in position. The studs are instrumental in locking the magnets and preventing any radial dislocations. The method of mounting is shown in Fig. 5. The brass studs are lighter in weight and do not add too much to the weight of the structure. The studs also does way with the requirement of using any adhesive required for mounting the magnets over the magnet mounting plates.

A series of coil plates (12), (13), (14) and (15) as shown in Fig. 6 are connected in series in a special technique to make the design fail safe in the event of failure of any of the coil plates. Even if two of the coil plates fail to provide necessary output, the connection as shown in Fig.6 is so made that the other two can be connected in series or parallel as the need be. Thus 6 coils comes out of a three phase star/delta connected circuit as against conventional 3 wires in three phase AC connection.
The stacked coil plates as shown in Fig. 4(B) are also connected in series and parallel using the connection diagram as shown in Fig. 6.


APPLICATIONS:
The above apparatus can have the following applications:
1. Coastal On grid applications: The generator can be coupled with wind turbine for power production. Generated power will be distributed on grid and metered.
2. Green hydrogen generation: Green hydrogen is the future fuel in the world. Hydrogen gas is extracted from water through electrolysis. Electrolysis of water is an energy intensive process. Hydrogen gas obtained through electrolysis with application of renewable energy is green hydrogen. The present invention is suitable to provide energy for extracting green hydrogen.
3. River on grid application: The generator can be employed on low speed river sides for power production. The generated power can be stored in battery or be distributed in grids.
4. Village electrification: The power requirement in villages range from 200 watt to 350 watt per hour. The system in place can meet energy requirements of hundred households with least maintenance cost. The system will ensure zero electricity bill and dependence on grid power will not be there. Excess power generated if any can be supplied back to grid for further revenue generation.
5. EV vehicle charging system: EV vehicles, two wheelers and four wheelers are flooding Indian markets and around the world. A four wheeler EV system operates on 25 to 30 kWh lithium polymer battery systems. The entire system gets charged in 8 to 9 hours. The present system in place, charging can be ascertained whole day and even during night time. The generators can power systems to be positioned besides roadways with proper alteration in structure for increasing battery charging terminals of EV vehicles. The system can be installed as an additional facility in petrol pumps for charging EV vehicles on the go.

, Claims: CLAIMS:
1. We claim a method consisting:
Wind turbine generator with stud supported curved magnets with multiple row of magnets (1) positioned over a single rotor plate sandwiched between coil plates (5) positioned on the base plate and the said coil plates are connected in series and parallel in a fail-safe design and the coils are curved and held together in a circular pattern with resin moulding strengthened with appropriate percentage by volume of carbon nano tube.

2. Wind turbine generator as claimed in claim 1, wherein the magnets (1) are curved and positioned over metal rotor plate as a cantilever with the help of studs (11) and not using any adhesive and a single rotor plate (2) can be used to hold multiple rows of magnets positioned circumferentially, separated by a gap and the said studs are held steady with fasteners attached from either side.
3. Wind turbine generator as claimed in claim 1, wherein copper coils (9) are curved to fit in a round curvature and are held together with resin moulding (10), the thus formed coil plates (5), (6), (7) & (8) are kept on the base plate concentrically in radial direction and also stacked vertically as shown in Fig. 4(B) for optimum utilization of space, also the above said resin moulding is strengthened with an addition of appropriate percentage by volume of Carbon nano-tube.

4. Wind turbine generator as claimed in claim 1, wherein the coil plates (5), (6), (7) & (8) are connected in series and parallel as shown in Fig. 6 in a fail-safe mode, wherein 3 phase line voltage is available from the coils in the event of failure of any of the interconnected coil plates.

Filing Date: 26th day of October 2024

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