Description:FIELD OF THE DISCLOSURE
The present disclosure generally relates to electric motors. More specifically, the present disclosure relates to a brushless DC electric motor which is magnet-free and has axial flux line and method for working thereof.
BACKGROUND
An electric motor involves a principle of conversion of electrical energy into mechanical energy. All types of motors include stator and rotor. The motors use electromagnet in the stator and generate variable electromagnetic field. AC motors use Induction and Reluctance properties of AC current. It has three phase AC supply which creates electromagnets and Rotating Magnetic Field (RMF) in the Stator. Because of Induction and Reluctance properties thereof, it creates electromagnet and RMF in rotor as well which follows and lags behind the stator RMF. Then, magnetic flux of stator and rotor interact and motor gradually start spinning.
DC motors has permanent magnets in its rotor having always ON and fixed magnetic field. So, whenever pulsating direct current (DC) supply in the stator coils, it creates electromagnets with Rotating magnetic Field. Flux of Permanent magnet instantly interact with the flux of rotating magnetic field and so motor start spinning.
Brushed DC motor uses permanent magnet in stator part and electromagnet in rotor Part. Current in the rotor of Brushed DC motor supplies through the brushes to the commutator ring. The commuter ring then supply current to the electromagnet coil/ Armature. The commutator ring keeps on rotating with the rotor and its connection with the brushes keeps on changing (switching on and off) and hence creating electromagnet in the rotor.
Induction and reluctance generate comparatively weak and low-density magnetic flux in the rotor, which lags behind and takes significant time and energy, because of I2R losses and Hysteresis thereby degrading AC motors' performance and efficiency. But due to absence of the permanent magnet in the rotor, it has extraordinary life cycle and highly economical.
On the other hand, DC motors are high performance motors which instantly create electromagnet with RMF as current supply to rotate. But it is highly costly and have low shelf life.
Out of all the motors, Brushless DC electric motor (BLDC) is recent one and has been known for its highest efficiency, excellent controllability and power saving advantages. In BLDC motors, rotation is achieved by changing the direction of the magnetic fields generated by the stator coils. Each coil in the stator creates and change the amplitude and direction of its magnetic field individually. To control the rotation, the Voltage, amp, polarity and frequency of each DC pulses of the current into these coils can be changed.
However, there are certain drawbacks of existing BLDC motors. Primarily, higher cost of the BLDC motors as they involve permanent magnets which are quite expensive. Also, the magnets are made up from Neodymium which is a rare earth material and not sufficiently available to meet the growing global demand of electric motors. Neodymium (Nd-Fe-B) and Samarium Cobalt (SmCo) are the two most common types of rare earth magnet materials. Since they both come from the same series of metals, they have similar properties and crystal structures. Both types are extremely strong, and they tend to be brittle. Manufacturing cost of the magnets is also high. As the number and size of the magnets is higher, thus cost also increases tremendously per motor. The existing motors use iron and magnets which may lead to have tremendous consequential impacts on cogging, noise, and vibration of the motor. Also, the existing motors require lubrication from time to time for efficient working.
Therefore, there exists a need to get rid of the aforementioned issues.
OBJECTS OF THE PRESENT DISCLOSURE
An object of the present disclosure is to overcome one or more drawbacks associated with conventional mechanisms.
An object of the present disclosure is to provide a brushless DC electric motor which is magnet-free and has axial flux line.
Another object of the present disclosure is to provide a brushless DC electric motor which is cost effective, reliable, and environment friendly
Another object of the present disclosure is to provide a brushless DC electric motor which eliminates the reliance on the supply chain of rare earth materials.
Another object of the present disclosure is to provide a brushless DC electric motor which has high power density, low losses and high efficiency motor, thereby making such motor suitable for different applications including such as but not limited to electric vehicles, industrial applications- for example pumps, compressors, conveyor systems, and robotics such as robotic arms and drones.
Another object of the present disclosure is to provide a brushless DC electric motor which is of compact design and has precise control.
Another object of the present disclosure is to provide a brushless DC electric motor which is configured to enable current flow through the bearings.
Another object of the present disclosure is to provide a method for working of magnet-free brushless DC electric motor.
SUMMARY
Various objects, features, aspects and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components.
In one aspect of the present disclosure, a magnet-free axial flux brushless DC (BLDC) motor (100) is disclosed. The motor (100) includes a case (102) which further includes a fiber shaft (104). Multiple stators (106) and multiple rotors (108) wound around the shaft (104) in alternative arrangement. Each of the stators (106) and the rotors (108) include multiple electromagnetic coils arranged in a pattern on a ferromagnetic printed circuit board. The rotors (108) are in synchronization with that of the stators (106). In an embodiment, the motor (100) can be without the case (102). At least one controller (110) is worn around the shaft (104) towards a lower portion thereof. The CONTROLLER (110) supplies three-phase current to the stator (106) to generate rotating magnetic field, and also supplies three-phase current to the rotor (108) via a plurality of self-lubricating and conducting bearings (114). Multiple self-lubricating and conducting bearings (114) are wound around the shaft (104) at a plurality of positions. A throttle signal input (118) is directly connected to the CONTROLLER (110). The throttle signal input (118) includes optional VCC wire, signal wire, and signal ground wire. Multiple wires (SR, SY,
SB) and (RR, RY, RB) through which the CONTROLLER (110) supplying three-phase current to the stator (106) and the rotor (108) respectively.

In another aspect of the present disclosure, a method (400) for working of the magnet free axial flux brushless DC (BLDC) motor (100) is disclosed. The method (400) involves drawing current from the battery or through the Power Distribution board (116) by the controller (110), followed by receiving signal from the throttle input (118) to the controller (110). The method (400) further includes supplying three-phase current to each of the plurality of stators (106) directly through the wires (SR, SB, SY), followed by generating rotating magnetic field when the stators (106) energized with electric current, and supplying three-phase current to each of the plurality of rotors (108) through the wires (RR, RB, RY) via the plurality of self-lubricating current conducting bearing (114). Ensuring continuity of the current in the rotor (108) without breaking the circuit at the rotating part of the outer race and inner race of the bearing (114A, 114B, 114C), followed by generating rotating magnetic field in the rotor (108) in synchronous with the stator (106) rotating magnetic field when the rotor (108) energized with electric current.
In another aspect of the present disclosure, a magnet-free axial flux brushless DC (BLDC) motor (500) is disclosed. The motor (500) includes a case (502) which further includes a fiber shaft (504). The motor (500) also includes multiple stators (506) and multiple rotors (508) wound around the shaft (504) in alternative arrangement. Each of the stators (506) and the rotors (508) include multiple electromagnetic coils arranged in a pattern on a ferromagnetic printed circuit board. The motor (500) also includes at least one controller (510A) wound around the shaft (504) towards a lower portion thereof. The controller (510A) supplies three-phase current to the rotors (508) directly through the wires (RR, RY, RB) by generating rotating magnetic field when the rotor (506) energized with electric current. At least one controller (510B) is worn around the shaft (504) towards a lower portion thereof and in alignment with that of the controller (510A). The controller (510B) supplies three-phase current to the stators (506) directly through the wires (SR, SY, SB) to generate rotating magnetic field. Multiple self-lubricating bearings (514) are wound around the shaft (504) at a plurality of positions to conduct electric current to the controller (510A). A throttle signal input (518) is directly connected to the controller (510B).
In yet another embodiment of the present disclosure, a method (700) for working of the magnet free axial flux brushless DC (BLDC) motor (500) is disclosed. The method (700) involves drawing current from the battery or through the Power Distribution board (516) via the bearings (514A, 514B) by the controller (510A), followed by causing continuity of current flow in the controller (510A) without breaking circuit at the rotating part of the outer race and inner race of Bearings (514A and 514B), followed by drawing current from the battery or through the power distribution board (516) directly by the controller (510B), followed by receiving signal through the throttle input (518) to the controller (510B). The method (500) further involves exchanging optical signals between the controller (510A) and the controller (510B) through each of the corresponding optical/wireless signal Transmitter, and optical/wireless signal receiver respectively for synchronization of the rotor (508) and the stator (506) rotating magnetic field, followed by supplying three-phase current to each of the plurality of stators (506) directly through the wires (SR, SB, SY) via the controller (510B) and supplying three-phase current to each of the plurality of rotors (508) directly through the wires (RR, RB, RY) via the controller (510A). The method (700) further involves generating synchronous rotating magnetic field between the stators (506) and the rotors (508) when the stators (506) and the rotors (508) energized with electric current and causing motor to rotate.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects, features, and advantages of the embodiment will be apparent from the following detailed description when read with reference to the accompanying drawings. In the drawings, wherein like reference numerals denote corresponding parts throughout the several views:
Referring to Figure 1, shows a schematic view of a magnet-free axial flux brushless DC (BLDC) motor (100) comprising at least one controller and at least three bearings, in accordance with an illustrative embodiment of the present disclosure;
Referring to Figures 2A, 2B, and 2C, show exemplary configurations of a bearing (Figure 2A), and delta configuration and star configuration of arrangement of electromagnetic coils (Figures 2B, 2C) in rotor/stator of the motor (100) respectively, in accordance with the illustrative embodiment of the present disclosure;
Referring to Figure 3, shows a circuitry of the magnet-free axial flux brushless DC (BLDC) motor (100), in accordance with the illustrative embodiment of the present disclosure;
Referring to Figure 4, illustrates a method (400) for working of the motor (100) in accordance with another illustrative embodiment of the present disclosure;
Referring to Figure 5, shows a schematic view of a magnet-free axial flux brushless DC (BLDC) motor (500) comprising at least two controllers and at least two bearings, in accordance with another illustrative embodiment of the present disclosure;
Referring to Figure 6, shows a circuitry of the magnet-free axial flux brushless DC (BLDC) motor (500), in accordance with the illustrative embodiment of the present disclosure;
Referring to Figure 7, illustrates a method (700) for working of the motor (500) in accordance with another illustrative embodiment of the present disclosure;
Referring to Figure 8, shows a schematic representation of an induced current bearing (800) for the current induction in the inner race from the outer race of the bearing induced bearing (800), in accordance with the illustrative embodiment of the present disclosure;
Referring to Figure 9A, shows a schematic view of circuitry comprising at least two conducting bearings of the motor (500) replaced by one induced bearing, in accordance with another illustrative embodiment of the present disclosure;
Referring to Figure 9B, shows a schematic view of circuitry comprising three conducting bearings of the BLDC motor (100) replaced by two induced bearings, in accordance with another illustrative embodiment of the present disclosure;
Referring to Figure 9C, shows a schematic view of a circuit comprising at least three-phase current conducting wire in rotor, and creating delta configuration connection, in accordance with another illustrative embodiment of the present disclosure; and
Figures 10A-10C, show graphs showing speed and efficiency as a function of torque (Figure 10A), efficiency of the motor (100) as a function of power to load (Figure 10B), and current and power as a function of torque (Figure 10C), in accordance with the illustrative embodiment of the present disclosure.
DETAILED DSECRIPTION OF THE PREFERRED EMBODIMENTS
Many modifications will be apparent to those skilled in the art without departing from the scope of the present invention as hereinbefore described with reference to the accompanying drawings.
Throughout this specification and the claims which follow, unless the context requires otherwise, the word “comprise”, and variations such as “comprises” and “comprising”, will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.
As used herein, the singular forms “a”, “an”, “the” include plural referents unless the context clearly dictates otherwise. Further, the terms “like”, “as such”, “for example”, “including” are meant to introduce examples which further clarify more general subject matter, and should be contemplated for the persons skilled in the art to understand the subject matter.
Figure 1 shows a schematic view of a magnet-free axial flux brushless DC (BLDC) motor (100). The motor (100) includes a case (102) including a number of components. The case (102) includes a fiber shaft (104). The shaft (104) has multiple stators (106) and multiple rotors (108) wound around the shaft (104) alternatively such that the rotors (108) are fixed to the shaft (104) to enable rotation of the rotor (108) with respect to the rotation of the shaft (104). The stators (106) are fixed to the case (102) which are static. Each of the stators (106) and the rotors (108) include multiple electromagnetic coils arranged on a ferromagnetic printed circuit board. The connection topology may include such as but not limited to delta (160) as shown in Figure 2B, star (170) as shown in Figure 2C. The rotors (108) work in synchronization with that of the stators (106).
The motor (100) includes a controller (110) which is worn around the shaft (104) towards a lower portion thereof. It is contemplated that the controller (110) supplies three-phase current to the stator (106) to generate rotating magnetic field as the stators (106) get energized with electric current. Such a supply of current is passed through phase wires indicated as SR, SB, SY in Figure 1. R denotes red colour, Y denotes yellow colour and B denotes black colour.
The controller (110) is also configured to supply three-phase current to the rotor (108) via multiple self-lubricating bearings (114). The bearings (114) are configured to enable continuity of current flow without breaking circuit at a rotating point. Each of the rotor phase wires (RR, RB, RY) through which current or power is supplied to the rotor (108) run from outer race and inner race of the bearings (114).
The bearings (114) as shown in Figure 2A include an inner race (154), surrounded by multiple balls (150). Multiple balls (150) are fixed and kept at a distance from each other. The balls (150) are surrounded by a wall called outer race (152).
The bearings (114) are well known in the art, however the bearings (114) disclosed herein are self-lubricating and made up of metal alloy. Thus, the bearings (114) are conducting in nature and allow current to pass therethrough. It ensures continuous and steady flow of the charges/current to the rotor part without breaking the circuit. This metal alloy bearing doesn't need any external lubrication or lubricating agent, and has lowest friction coefficient. It is also the hardest metal and result no to negligible wear and tear.
The bearings (114) as shown in Figure 1 are wound around the shaft (104) at multiple exemplary positions. In the embodiment, there are three bearings (114). For example, a first bearing (114A) is wound around an upper portion of the shaft (104), a second bearing (114B) is wound around the shaft (104) above the controller (110), and a third bearing (114C) is wound around a lower end of the shaft (104).
The controller (110) is connected to a battery through a power distribution board (PDB) (116). The battery is a power source generated from one or more of renewable resources, and non-renewable resources. The PDB (116) is configured to supply current to the controller (110) to energize the rotor coils (108) with required amplitude and polarity of electric current in synchronous to the stator coils (106) to ensure continuous and stronger high RPM and torque.
The controller (110) is also in direct connection with throttle input (118). The controller (110) and the throttle input (118), each of which includes input from wires for VCC, GND and signal.
As shown in a circuitry in Figure 3 and a method (400) having steps shown in flowchart in Figure 4, the controller (110) draws current from the battery or through the Power Distribution board (116). Simultaneously, signal is received through the throttle input (118) to the controller (110). Three-phase current is supplied to each of the stators (106) directly through the wires (SR, SB, SY), thereby generating a rotating magnetic field as the stators (106) energized with electric current. Three-phase current is supplied to each of the plurality of rotors (108) via multiple self-lubricating conducting bearings (114) to cause continuity of current flow in the rotor (108) without breaking circuit at rotating points to synchronize the rotors (108) RMF with that of the stators (106) RMF.
Figure 5 discloses a magnet-free axial flux brushless DC (BLDC) motor (500). The motor (500) includes a case (502) which includes a fiber shaft (504). In this embodiment, multiple stators (506) and rotors (508) are wound around the shaft (504) in alternative arrangement in same way as that of the rotors (108) and the stators (106) as explained in detail herein above.
The motor (500) includes at least one controller (510A) wound around the shaft (504). The controller (510A) is configured to supply three-phase current to the rotors (508) directly through the wires (RR, RB, RY). Wires of Vin and GND of the controller (510A) are connected to outer and inner races of the bearings (514A, 514B).
The bearings (514) include two exemplary bearings including a first bearing (514A) wound around an upper portion of the shaft (504), and a second bearing (514B) wound around a lower end of the shaft (504).
The motor (500) includes controller (510B) worn around the shaft (504). The controller (510B) is in alignment with that of the controller (510A). The controller (510B) is configured to supply three-phase current to the stator (506) to generate rotating magnetic field.
Both the controller (510A) and the controller (510B) are connected to a battery through a power distribution board (PDB) (516) such that the PDB (516) supplies direct current to the controller (510B) while the PDB (516) supplies direct current to the bearings (514A, 514B) to further pass to the controller (510A). The controller (510B) is configured to be connected with throttle input (518) directly Through the three wires setup which includes VCC wire, signal wire and ground wire. thereby receiving signal input for VCC and GND such that the controller (510B) receives the direct input signal from the throttle input (518).
As shown in circuitry in Figure 6, each of the controller (510A) and the controller (510B) includes Hall sensor, optical/wireless signal Transmitter, and optical/wireless signal Receiver. The controller (510A) and the controller (510B) are configured to transmit and receive optical/wireless signals to each other through the corresponding optical/wireless signal Transmitter, and optical/wireless signal Receiver respectively for synchronization of the rotor (508) and the stator (506).
In the embodiment, the bearings (514) are ordinary bearings same as that of the bearings (114) explained hereinabove in conjunction with Figure 2A.
However, in some embodiments, the bearings can be induced bearings, explained hereinafter.
As shown in Figure 7, a method (700) for working of the magnet free axial flux brushless DC (BLDC) motor (500) is disclosed. The method (700) involves drawing current by the controller (510A) from the battery through the Power Distribution board (516) via the bearings (514A, 514B), followed by drawing current by the controller (510B) from the battery through the Power Distribution board (516) directly via Vin and Ground wire, followed by receiving signal through the throttle input (518) to the controller (510B). The method (700) involves exchanging optical/wireless signals between the controller (510A) and the controller (510B) through each of the corresponding optical/wireless signal Transmitter, and optical/wireless signal Receiver respectively for synchronization of the rotor (508) and the stator (506), followed by supplying three-phase current to each of the plurality of stators (506) directly through the wires (SR, SB, SY) via the controller (510B) and supplying three-phase current to each of the plurality of rotors (508) directly through the wires (RR, RB, RY) via the controller (510A), thereby generating a synchronous rotating magnetic field when the stators (506) and the rotor (508) energized with electric current. Thus, the method (700) involves causing continuity of current flow into the rotor (508) without breaking the circuit at the rotating point of the outer race and inner race of the bearing (514A and 514B).
Figure 8 shows a schematic view of the induced bearing (800). The induced bearing (800) includes an induction coil (808) wrapped around an inner race (804) and another induction coil (806) wrapped around an outer race (810). The bearing (800) includes multiple balls (802) disposed in a space between the outer race (810) and the inner race (804).
As shown in circuitry in Figure 9A, the motor (500) includes at least one induction bearing (800) to which the PDB (518) is connected. The PDB (518) supplies DC current to the controller (510B). The PDB (518) also converts DC to AC and supplies thereto to the induction coil (806) wrapped around an outer race (810). From the outer race (810), the AC current induce to the coil (808) wrapped around the inner race (804). The AC current is further supplied to the controller (510A). At controller (510A), rectifier diodes convert AC to rough DC and supplies it to the DC Bus. Further on, DC Bus, capacitor smoothens the DC current and provides smooth DC to inverter, followed by transistors supply three phase current to the rotor (508) based on the optical/wireless signal receiver as shown in Figure 9A. Figure 9B shows another aspect in which two induced bearings are in connection with one controller (510B). The controller is configured to supply three phase current to the stator (506) directly through the wire (SR, SY, SB) and also configured to supply three phase current to the rotor (508) but through the 2 induced bearings (800). In figure 9B the rotor (508) coils are connected in star connection topology to supply current and energize rotor (508) coil and the bearings (800) is connected/configured to supply current to the rotor (508) with star connection topology. Figure 9C shows delta connection topology in the rotor (508) coils and its induced bearings (800) are connected/configured to supply three phase current to rotor (508) coils arranged in delta connection topology. In some embodiments, the motor (500) is devoid of any controller and involves AC supply at both terminals of the stator (506) and the rotor (508). In such cases, the motor (500) may be applicable for installation in small electrical appliances such as fan, washing machines, etc.
Figures 10A-10C, show graphs showing speed and efficiency as a function of torque (Figure 10A), efficiency of the motor (100) as a function of power to load (Figure 10B), and current and power as a function of torque (Figure 10C). For input of 1kW of electrical energy at 100% load, the exemplary motors of the present disclosure provide 1.32 Hp output i.e., 98-99% efficiency.
The motor (100) and other related embodiments provide cost-efficiency, sustainability, environmental friendliness, high efficiency, compact design, and precise control make it suitable for various applications, including electric vehicles, industrial applications, and robotics.
Electric vehicles: The high-power density and efficiency make it suitable for electric vehicle propulsion systems.
Industrial applications: The motor's precise control and high efficiency make it ideal for various industrial applications, such as pumps, compressors, and conveyor systems.
Robotics: The motor's compact design and precise control make it suitable for robotics applications, such as robotic arms and drones.
The foregoing descriptions of exemplary embodiments of the present disclosure have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the disclosure to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The exemplary embodiments were chosen and descriptions in order to best explain the principles of the disclosure and its practical application, to thereby enable others skilled in the art to best utilize the disclosure and various embodiments with various modifications as are suited to the particular use contemplated.
, Claims:We Claim
1. A magnet-free axial flux brushless DC (BLDC) motor (100) comprising:
a fiber shaft (104);
a plurality of stators (106) and a plurality of rotors (108) wound around the shaft (104) in alternative arrangement, each of which comprising a plurality of electromagnetic coils aligned on a printed circuit board, where coil excitation of the rotors (108) is in synchronization with the coil excitation of the stators (106);
at least one controller (110) worn around the shaft (104), where the controller (110) supplies three-phase current to the stator (106) to generate rotating magnetic field, and also supplies three-phase current to the rotor (108) via a plurality of self-lubricating and conducting bearings (114);
the plurality of self-lubricating and conducting bearings (114) wound around the shaft (104) at a plurality of positions;
a throttle signal input (118) directly connected to the controller (110); and
a plurality of wires (SR, SY, SB) and (RR, RY, RB) through which the controller (110) supplying three-phase current to the stator (106) and the rotor (108) respectively.

2. The motor (100) as claimed in claim 1, wherein the stators (106) are fixed to a case (102) while the rotors (108) are fixed to the shaft (104).
3. The motor (100) as claimed in claim 1, wherein the shaft (104) and the electromagnetic coils attached thereto are fixed and screwed to an external surface thereof such that the case (102) becomes the rotor and the shaft (104) with the stator (106) becomes is the stator.
4. The motor (100) as claimed in claim 1, wherein the plurality of self-lubricating conducting bearings (114) comprising a first bearing (114A) wound around an upper portion of the shaft (104) at a first rotating point between the shaft (104) and the case (102) to support the shaft (104) and supply first phase current from the case (102) to the rotor (108), a second bearing (114B) wound anywhere on the shaft (104), and a third bearing (114C) wound around a lower end of the shaft (104) at a second rotating point between shaft (104) and the motor case (102) to hold and support the shaft (104) with motor case (102) and supply third phase current from the motor case to rotor coil (108).
5. The motor (100) as claimed in claim 1, wherein the controller (110) is connected to a battery through a power distribution board (PDB) (116).
6. A method (400) for working of the magnet free axial flux brushless DC (BLDC) motor (100) comprising:
a case (102) comprising:
a fiber shaft (104);
a plurality of stators (106) and a plurality of rotors (108) wound around the shaft (104) in alternative arrangement, each of which comprising a plurality of electromagnetic coils arranged in a pattern on a printed circuit board, where the rotors (108) are in synchronization with that of the stators (106), generating a rotating magnetic field when energized with electric current;
at least one controller (110) worn around the shaft (104), where the controller (110) supplies three-phase current to the stator (106) to generate rotating magnetic field, and also supplies three-phase current to the rotor (108) via a plurality of self-lubricating and conducting bearings (114); to have continuity of current flow without breaking circuit at rotating point of outer race and inner race of the bearing (114);
the plurality of self-lubricating bearings (114) wound around the shaft (104) at a plurality of positions to support and hold the shaft (104) with the motor case (102);
a throttle signal input (118) directly connected to the controller (110); and
a plurality of wires (SR, SY, SB) and (RR, RY, RB) through which the controller (110) supplying three-phase current to the stator (106) and the rotor (108) respectively;
the method (400) comprising:
drawing current directly from the battery or through the Power Distribution board (116) by the controller (110);
receiving signal through the throttle input (118) to the controller (110);
supplying three-phase current to each of the plurality of stators (106) directly through the wires (SR, SB, SY);
generating a rotating magnetic field when the stators (106) energized with electric current;
supplying three-phase current to each of the plurality of rotors (108) via the plurality of self-lubricating conducting bearings (114) to cause continuity of current flow without breaking circuit at rotating point of outer race and inner race of the bearings (114A, 114B, 114C) to synchronize coil excitation of the rotors (108) with that of coil excitation of the stators (106).
7. The method (400) as claimed in claim 6, wherein the method (400) comprising the wires (RR, RB, RY) connecting to inner race and outer race of the plurality of self-lubricating bearings (114).
8. A magnet-free axial flux brushless DC (BLDC) motor (500) comprising:
a fiber shaft (504);
a plurality of stators (506) and a plurality of rotors (508) wound around the shaft (504) in alternative arrangement, each of which comprising a plurality of electromagnetic coils arranged in a pattern on a printed circuit board, where coil excitation of the rotors (508) is in synchronization with that coil excitation of the stators coil excitation (506);
at least one controller (510A) wound around the shaft (504) towards a lower portion thereof, the controller (510A) draws current through plurality of self-lubricating and conducting bearing from the power source through the PDB (516) and supplies 3 phase current directly to the rotor (508) via wires (RR, RY, RB);
at least controller (510B) worn around the shaft (504) and in alignment with that of the controller (510A), where the controller (510B) supplies three-phase current directly to the stator (506) through the wires (SR, SY, SB) to generate rotating magnetic field;
the plurality of self-lubricating and conducting bearings (514) wound around the shaft (504) at a plurality of positions to supply current to the rotor controller (510A) from the power source through the power distribution board (516) without breaking the circuit at the rotating point of its outer race and inner race and also support and hold the shaft with a case (502);
a throttle signal input (518) directly connected to the CONTROLLER (510B); and
a plurality of wires (RR, RY, RB) and (SR, SY, SB) through which each of the controller (510A, 510B) supplying three-phase current to the rotor (508) and the stator (506) respectively.
9. The motor (500) as claimed in claim 8, wherein the stators (506) are fixed to the case (502) while the rotors (508) are fixed to the shaft (504).
10. The motor (500) as claimed in claim 8, wherein the plurality of self-lubricating conducting bearings (514) comprising a first bearing (514A) wound around an upper portion of the shaft (504), and a second bearing (514B) wound around a lower end of the shaft (504) to support the shaft (504) with the motor case (502) and supply current to the rotor (508) without breaking the circuit at the rotating point of outer race and inner race of the bearing (514A and 514B).
11. The motor (500) as claimed in claim 8, wherein the controller (510A) and the controller (510B) are connected to a battery through a power distribution board (PDB) (516).
12. The motor (500) as claimed in claim 8, wherein each of the controller (510A) and the controller (510B) comprising Hall sensor, optical/wireless signal Transmitter, and optical/wireless signal Receiver, the controller (510A) and the controller (510B) transmit and receive optical /wireless signals to each other through the corresponding optical/wireless signal Transmitter, and optical/wireless signal Receiver respectively for synchronization of coil excitation of the rotor (508) and coil excitation of the stator (506) coil excitation.
13. The motor (500) as claimed in claim 8, wherein wires of Vin and GND of the controller (510A) are connected to PDB (516) through outer and inner races of the bearings (514A, 514B).
14. The motor (500) as claimed in claim 8, wherein the plurality of bearings (514) comprising an outer race, an inner race and balls fixed around the inner race at a distance from each other.
15. The motor (500) as claimed in claim 8, wherein the motor (500) comprising at least one induced bearing (800) comprising an induction coil wrapped around each of an inner race and an outer race.
16. The motor (500) as claimed in claim 1, wherein the motor (100) comprising at least two induced bearings (802A, 802B) comprising an induction coil wrapped around each of an inner race and an outer race.
17. The motor (500) as claimed in claim 16, wherein the PDB (516) supplies AC current / Pulsating DC to the controller (510A) through induced bearing (800), the controller (510A) converts thereto into three phase supply and supplies thereto to the rotor (508) through the three phase wires (RR, RY, RB).
18. A method (700) for working of the magnet free axial flux brushless DC (BLDC) motor (500) comprising:
a fiber shaft (504);
a plurality of stators (506) and a plurality of rotors (508) wound around the shaft (504) in alternative arrangement, each of which comprising a plurality of electromagnetic coils arranged in a pattern on a printed circuit board, where coil excitation of the rotors (508) is in synchronization with coil excitation of the stators (506); to generate a synchronous rotating magnetic field when energized with electric current;
at least one controller (510) wound around the shaft (504) thereof, the controller (510A) draws current through the plurality of self-lubricating and conducting bearings from the power source through the PDB (516) and supplies 3 phase current directly to the rotor (508) via wires (RR, RY, RB);
at least controller (510B) worn around the shaft (504) towards a lower portion thereof and in concentric with that of the controller (510A), where the controller (510B) supplies three-phase current to the stator (506) to generate rotating magnetic field;
the plurality of self-lubricating conducting bearings (514) wound around the shaft (504) at a plurality of positions to hold shaft (504) with the motor case (502) and also conduct current in the rotor (508) without breaking the circuit at the rotating inner race and outer race of the bearings (514A, 514B);
a throttle signal input (518) directly connected to the controller (510B);
and
a plurality of wires (RR, RY, RB) and (SR, SY, SB) through which each of the controllers (510A, 510B) supplying three-phase current to the rotor (508) and the stator (506) respectively;
the method (700) comprising:
drawing current from the battery through the Power Distribution board (516) via the bearings (514A, 514B) by the controller (510B);
receiving signal through the throttle input (518) to the controller (510B);
exchanging optical signals between the controller (510A) and the controller (510B) through through their respective optical/wireless transmitters (520A, 522B) and optical/wireless receivers (522A, 520B) to increase or decrease the motor (500) RPM and torque by synchronising coil excitation of stator (506) and rotor (508);
supplying three-phase current to each of the plurality of stators (506) directly through the wires (SR, SB, SY) via the controller (510B);
supplying three-phase current to each of the plurality of rotors (508) directly through the wires (RR, RB, RY) via the controller (510A);
generating a synchronous rotating magnetic field when the stators (506) coils and rotor (508) coils energized with electric current;
causing continuity of current flow in the CONTROLLER (510A) directly from the battery or through the PDB without breaking circuit at the rotating point of outer race and inner race of the bearing (514A, 514B).