WO2021002775A1

WO2021002775A1 - Motor-generator with magnetic concentrators

Info

Publication number: WO2021002775A1
Application number: PCT/RU2020/000313
Authority: WO
Inventors: Василий Васильевич ШКОНДИН
Original assignee: Василий Васильевич ШКОНДИН
Priority date: 2019-07-02
Filing date: 2020-06-27
Publication date: 2021-01-07
Also published as: RU2708635C1

Abstract

The invention relates to the field of DC motors and is directed toward a simplified design, improved weight and size characteristics, increased efficiency and increased maximum torque at low currents. A motor-generator comprises a stator having two annular magnetic cores with alternating polarity permanent magnets and laminations arranged thereon, and a rotor having electromagnets attached thereto which are connected by current collectors to a distributing collector. A magnetic core comprises an equal even number of permanent magnets and concentrators, with two pairs of permanent magnets of different polarity being separated by a concentrator such that like permanent magnets are situated adjacent the concentrator, the polarity of the magnets of the different magnetic cores alternates in a transverse direction, and the concentrators of one magnetic core are situated opposite the concentrators of the other magnetic core. On the rotor, transverse horseshoe-shaped electromagnets are mounted opposite one another and are provided with two in-series oppositely wound coils, each of which is disposed above one of the magnetic cores. The distributing collector comprises an equal even number of alternating positive laminations, negative laminations and return laminations, the latter being connectable by a rectifier to a current source. The number of laminations of each type is equal to the number of concentrators.

Description

MOTOR-GENERATOR WITH MAGNETIC CONCENTRATORS

The invention relates to the field of direct current electric motors, in particular, gearless low voltage collector motors, and can be used as motor wheels in vehicles: electric bicycles, scooters, motorcycles, electric cars, etc., as well as in other fields of technology.

Modern vehicle development trends are leading to widespread adoption of electric and hybrid engines. In this regard, the most promising are gearless motor-wheels, in which the rotation of the wheel is caused directly by the electromagnetic interaction of the magnetic systems of the rotor and stator. For example, a built-in electric motor is known (WO 93/08999), comprising two main parts: a stationary stator fixed on an axis and having a magnetic circuit with permanent magnets spaced uniformly, and a movable rotor carrying a rim and containing at least two groups of electromagnets, and a distribution manifold fixed to the stator and having conductive plates connected to a direct current source. The current collectors are fixed on the rotor and have electrical contact with the plates of the distribution manifold.

The specified motor-wheel has various modifications and versions (US 6384496; US 6617746; RU 2129965; RU 2072261). The advantages of such a device include: the absence of a gearbox, the use of low-voltage power supplies, the absence of additional electronic circuits, the possibility of energy recuperation, small dimensions and weight. The combination of the main elements of such motors in combination with additional devices makes it possible to create motor-wheels similar in principle of operation and having the indicated advantages.

However, the described wheel motor and its variants have a number of disadvantages, the main one of which is the need for large starting and transient currents when starting and accelerating the vehicle. This leads to rapid wear and tear of the batteries and deterioration of the thermal regime. Another disadvantage is the lack of efficient recovery and use of electricity. Also, the named electric motors have low torque, which significantly limits the area of their practical use.

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SUBSTITUTE SHEET (RULE 26) Known technical solutions aimed at eliminating these disadvantages are associated with the use of high-voltage power supplies and complex control circuits, which makes them expensive and unreliable in operation (US 6791226; US 6727668; US 6355996).

Also known is an electric motor (RU 2285997), containing a stator with a circular magnetic circuit, on which an even number of permanent magnets with the same pitch is fixed;

a rotor separated from the stator by an air gap and carrying an even number of electromagnets, which are located in pairs opposite each other;

a distribution manifold attached to the stator housing and having circumferentially conductive plates connected with alternating polarity to a constant current source and separated by dielectric gaps;

current collectors installed with the possibility of contact with the collector plates, and each of the current collectors is connected to the same output of the windings of the corresponding electromagnets.

Each of the electromagnets has two coils with a serially opposite direction of the winding, and the windings of the coils of adjacent electromagnets are connected in series, and the terminals of the windings of opposite electromagnets, not connected to the current collectors, are interconnected. The number of permanent stator magnets equal to n and the number of rotor electromagnets equal to m are selected in such a way that they satisfy the relations:

n = 10 + 4k, where k is an integer taking the values 0, 1, 2, 3, etc.

m = 4 + 2L, where L is any integer satisfying the condition 0 <L <k.

The advantages of such a device include: the ability to recuperate electricity, a reduced level of sparking on the current collectors, as well as reversibility while maintaining a simple design and improving performance.

Also known is an asymmetric pulse electric motor (RU 96294), which is a further improvement of such devices. However, the further development of electric transport requires an expansion of the range of electric motors and an improvement in their operational and technical characteristics, primarily efficiency and energy consumption, and the ability to achieve high torque at low currents. The closest analogue is a pulsed electric motor for vehicles (RF patent N ° 2172261). This patent proposes an electric motor for mobile vehicles comprising a stator with two annular magnetic circuits, on which permanent magnets equidistant around the circumference are located, and an external rotor, on which electromagnets are fixed, connected through current collectors with a distribution manifold. Permanent magnets of north polarity are located on one ring-shaped magnetic circuit of the stator, and on the other - of south polarity, transverse magnetic conductive plates are placed between pairs of opposite poles. The electromagnets are transverse bipolar, and the distribution manifold is made with the possibility of converting direct current into a pulsed unidirectional current together with current collectors and fixed on the stator body with the direction of the axial lines of the copper plates parallel to the axial lines of the permanent stator magnets. In another embodiment of this invention, electromagnets are used in the form of clearly expressed quadroelectromagnets. Such electric motors have shown sufficient reliability and high torque. However, their operation revealed difficulties in their production and commissioning, limitation of the field of application (due to the relatively large weight and dimensions), high starting currents, significant energy consumption.

The present invention is aimed at simplifying the design, improving the mass-dimensional characteristics, increasing the efficiency (efficiency), increasing the maximum torque at low currents.

The claimed technical result is achieved in that the electric motor (motor-generator) made in accordance with the present invention contains: a stator with two ring-shaped magnetic circuits, on which permanent magnets with alternating polarity and magnetic conductive plates (concentrators) are located around the circumference; an external rotor, on which electromagnets are fixed, connected through current collectors with a distribution manifold.

Each magnetic circuit contains the same even number of permanent magnets of different polarity and concentrators. All these elements are installed with the same pitch, and two pairs of permanent magnets of different polarity are separated by one concentrator in such a way that permanent magnets of the same name adjoin the concentrator on both sides. In the transverse direction, the polarity of the magnets of different magnetic circuits alternates, and opposite the concentrators of one magnetic circuit there are concentrators of another magnetic circuit. The rotor is equipped with transverse horseshoe-shaped electromagnets, which are located opposite each other and have two coils with sequentially opposite winding direction, while each of the coils of the electromagnets is located above one of the magnetic circuits.

The gap between the permanent magnets of both polarities, the hubs and the rotor electromagnet cores is the same and remains constant as the motor rotates.

The distribution manifold contains the same even number of alternating positive, negative lamellas and return lamellas, which can be connected through a rectifier to a current source. The number of lamellas of each type is equal to the number of hubs.

The total number of permanent magnets and electromagnets in an electric motor depends on its purpose and dimensions. Typically, the number of permanent magnets of each polarity and concentrators is 2n, and the number of electromagnets is 2n + 2, where n is an integer. For individual vehicles (bicycles, scooters, motorcycles, etc.), it is preferable to use a scheme in which the number of electromagnets is 8, and the number of permanent magnets of each polarity and concentrators is 6.

This ratio of the number of electromagnets and permanent magnets and concentrators, their mutual arrangement, as well as the used switching scheme allows:

- to prevent oversaturation of the windings of electromagnets in peak current impulses and thereby avoid overheating;

- to create conditions for the inertial passage of electromagnets in a de-energized state of a significant sector (about 120 °), as well as the return ("reset" of pulses) of the counter-EMF through the return lamellas and diodes to the current source, which significantly increases the efficiency of the engine and its efficiency;

- to provide effective impulse magnetization reversal of electromagnets, allowing to achieve high torque at low currents.

The presence of a high proportion of the return EMF and the ability to effectively use the electric motor in the reverse mode as an electric generator allows the claimed device to be called a motor-generator.

Structurally, the electric motor can be made so that the rotor is located on the outside of the stator (for example, a motor-wheel for ground vehicles) or the rotor will be located inside the stator (for example, a propeller for water vehicles).

The essence of the invention is illustrated by the following drawings.

FIG. 1 shows a diagram of an electric motor made in accordance with the present invention;

FIG. 2 shows a cross-sectional axial section of an electric motor;

FIG. 3 shows a fragment of a stator with a double-row magnetic circuit;

FIG. 4 shows a schematic diagram of an electric motor.

Figures 1, 2 show an electric motor made in accordance with the present invention, which can be used as a wheel motor for various vehicles, for example, an electric bicycle, a scooter, a car, etc. The electric motor contains a shell (motor housing) 1, acting as a protective casing, and directly transmitting the rotation to the wheel. The shell is spoked to a wheel rim (not shown). The stator 2 of the electric motor is usually located inside the rotor 3. The stator 2 has two ring-shaped magnetic circuits 4, on each of which an even number of permanent magnets 5 with alternating polarity is fixed. Pairs of opposite magnets are separated by concentrators 6 (magnetic conductive plates having a size corresponding to the size of permanent magnets). All of the above elements are located with the same pitch, and in such a way that permanent magnets with the same polarity are adjacent to each hub on both sides. In the transverse direction, the polarity of the magnets of different magnetic circuits alternates, and opposite the concentrators of one magnetic circuit there are concentrators of another magnetic circuit. In this case, 6 magnets of different polarity and 6 concentrators are installed on each of the magnetic cores.

If necessary, the concentrators 6 can be made as a single piece together with the stator 2 (Fig. 3), and the permanent magnets 5 are installed in the corresponding spaces between them. In Figure 3, the concentrators 6 are designated by the letter "C", and the magnets 5 of the corresponding polarity are "N" or "S". This design makes it possible to reduce the number of technological operations in the manufacture of an electric motor.

The rotor 3 is separated from the stator by an air gap and carries an even number of identical transverse horseshoe-shaped electromagnets 7. In this case, eight pieces. Each electromagnet has two coils 8 with sequentially opposite direction of the winding, while each of the coils of the electromagnets is located above one of the magnetic cores. The electromagnets are arranged in pairs opposite each other and form four pairs. In the Figures, the start of the winding of the first coil is indicated by the letter "H", the end of the winding of the second coil is indicated by the letter "K". During operation of the electric motor, the coils 8 of the electromagnets 7 are powered from a direct current source (not shown) through the distribution manifold 9 and current collectors 10 (brushes). The distribution manifold 9 is stationary relative to the stator, and the current collectors 10 are connected to the rotor and, during its rotation, move relative to the current-carrying plates (lamellas), separated from each other by insulating gaps. The distribution manifold 9 contains the same even number of alternating positive lamellas 11, negative lamellae 12 (connected to the body) and return lamellas 13 (having the ability to connect through a rectifier, usually a diode, with a current source). Return lamellas 13 are also called pause. The plus of the power supply is usually connected by means of a wire going through an angled hole in the axle to the positive lamellas. The source minus is connected to the motor housing. From the return lamellas 13 of the distributor through the diodes through a separate wire 14, the back-EMF pulses are returned to the current source. The number of lamellas of each type is equal to the number of concentrators and in this case is six. The lamellas are located around the circumference of the collector 9 in such a way that the return lamellae 13 are installed with the same pitch, and around each of them are alternately two lamellae of the same polarity plus 1 1 or minus 12 (Fig. 1).

Two-pronged transverse electromagnets 7 move from the center lines of the concentrators 6 to the center lines of a number of fixed magnets 5 in a de-energized state on free attraction (sector F in Fig. 1). It is at these moments that the counter-EMF pulses are “dumped” into the current source through the diodes. In total, each electromagnet of the rotor, making one revolution around the inductor, one third of the circle passes as a de-energized flywheel, reinforced by the free attraction of permanent magnets.

FIG. 4 shows a schematic diagram of an electric motor. Two windings 8 of each electromagnet 7 are connected in series-oppositely. The ends of the windings of two diametrically opposite electromagnets (K) are closed together. The initial conclusions (H) of the windings of all eight electromagnets are fed to the current collectors 10, fixed opposite the corresponding electromagnet. The number of turns on the cores of two-pronged electromagnets is determined by the transformation ratio found empirically during the tests. is he equals 16 units (+/- 2 units). For example, for a core with a cross-sectional area of 4 cm ^{2, the} number of turns is 96 for each coil. It is preferable to connect a capacitor 15 in parallel to the windings of each two-pronged electromagnet. Usually, paper capacitors with a capacity of 1 to 6 μF are used. The resonant circuits organized in this way reduce the current consumption from the power source and increase the torque of the electric motor.

An electric motor made in accordance with the present invention may include several identical sections, each of which is similar to the devices described above. The number of such sections depends on the power of the power source and the required parameters of the vehicle.

EXAMPLE OF IMPLEMENTATION

The impulse electric motor (motor generator) for vehicles manufactured in accordance with the present invention has shown unique performance and high structural reliability. The baseline test model contained eight double-prong rotor electromagnets and twelve stator permanent magnets on each magnetic circuit. Cross-sectional area

•

the core was 4 cm and the number of turns was 96 for each coil. The supply voltage of the electric motor was 48 V.

Comparison of the parameters of this model with a pulse electric motor manufactured according to the patent RU 2172261 showed the best manufacturability of the claimed model (there is no need to manufacture complex patterns for quadroelectromagnets, less material consumption, easier assembly and adjustment of the electric motor, etc.); more significant torque was achieved at significantly lower currents. The inventive electric motor showed a higher efficiency (by 6-8%) and greater efficiency.

A comparative test was also carried out of an electric motor (motor generator with magnetic hubs) manufactured in accordance with the present invention with a serial motor for an EMCO scooter model Nova 2 kw RM3 (which is one of the leading models in its class). Comparative test results are presented in Table 1. Tab. one

Thus, the inventive electric motor has significantly improved operational and technical characteristics while maintaining the relative simplicity of design and reliability.

Claims

CLAIM

1. A pulse electric motor containing a stator with two ring-shaped magnetic circuits, on which permanent magnets with alternating polarity and magnetic conductive plates (concentrators) are located around the circumference, and an external rotor, on which electromagnets are fixed, connected through current collectors to a distribution collector, characterized in that

each magnetic circuit contains the same even number of permanent magnets of each polarity and concentrators, all installed with the same pitch, and two pairs of permanent magnets of different polarities are separated by one concentrator in such a way that the same permanent magnets adjoin the concentrator on both sides,

in the transverse direction, the polarity of the magnets of different magnetic circuits alternates, and opposite the concentrators of one magnetic circuit there are concentrators of another magnetic circuit;

electromagnets are transverse horseshoe-shaped, located opposite each other and have two coils with sequentially opposite direction of the winding, with each of the coils of the electromagnets located above one of the magnetic circuits; The distribution manifold contains the same even number of alternating positive, negative lamellas and return lamellas, which can be connected through a rectifier to a current source, the number of lamellas of each type is equal to the number of concentrators.

2, The pulse motor according to claim 1, characterized in that the number of electromagnets is 8, and the number of permanent magnets of each polarity and concentrators is 6.

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SUBSTITUTE SHEET (RULE 26)