RU2141159C1 - Permanent-magnet torque motor - Google Patents

Abstract

FIELD: electric drives. SUBSTANCE: magnet is provided with additional magnets abutting against ends of extreme magnets. Magnetic cores are mounted in bearings of stator hollow shaft. Alternating with magnets are electric blocks that have plate and heat sink whose slots accommodate coil sections and rotor position detectors. All magnets are installed in shells joined together and to magnets to form toroidal gaps for receiving electric blocks. Alternating magnetic fields are opposing each other. Leads of rotor position detectors and those of coil sections in rows of electric blocks are connected in series, in parallel or in series- and-parallel; they are connected through holes in hollow shaft to power supply and to control unit. Coils may be wound of insulated strips and made of electricity conducting nonretentive material. EFFECT: reduced size and improved reliability of motor due to high specific power and low thrusts on its bearings. 2 cl, 5 dwg

Description

 The invention relates to the field of electrical engineering, in particular to electric machines with non-contact switching sections of the stator windings depending on the position of the rotor using a frequency converter, i.e. to valve motors powered by a direct current source.

 Known magnetoelectric torque motors (MMD), containing a stator with a winding and a rotor with permanent magnets, with a fixed axis, with a hub and adjusting rings placed on the axis, while the toroidal magnetic circuits are made with trapezoidal teeth (1).

 Known MMD DC with disk anchors and magnets mounted on an annular yoke from its two opposite sides, with ferromagnetic annular yokes that reduce the noise level of the collector pulsations of the engine (2).

 Significant disadvantages of these devices are low power density and significant loads on the motor shaft bearings.

 Closest to the technical nature of the proposed technical solution is "Anchor for a gate type end-face electric motor" (3), containing a stator with a circuit board, on which are located a section of a quasi-ring shaped coil, a control unit composed of N branches for periodically connecting the sections to the source power supply, N Hall sensors located in the inner space of the sections, the outputs of which are connected respectively to the control inputs of the branches of the control unit, a rotor with a toroidal magnet, with an axial th magnetization and alternating polarity.

 The disadvantage of the device, as well as analogues, is the low power density and large loads on the shaft bearings.

 The objective of the invention is to eliminate these drawbacks and the creation of MMD with high specific power and low loads on the shaft bearings, leading to increased reliability of the engine.

 The problem is solved in that the proposed MMD contains a stator with a circuit board and connected in a quasi-ring coil section, a control unit composed of several branches for periodically connecting the sections to a power source, rotor displacement sensors, the outputs of which are connected to the control inputs of the control unit branches, the rotor with a toroidal magnet, with axial magnetization and alternating polarity, characterized in that the motor is equipped with additional magnets abutting against the ends of the extreme magnets to the magnetic circuits and, on bearings sitting on the hollow shaft of the stator, alternating with magnets electrical units containing a circuit board and a radiator, in the grooves of which are mounted coil sections and rotor position sensors, while all magnets are mounted in cages interconnected with magnets with the formation of toroidal the gaps in the space of which the electrical units are placed, and the alternating magnetic fields of the magnets are directed towards each other, and the outputs of the rotor position sensors and coil sections in the rows of electrical units are connected s in series or in parallel or in series-parallel and through the hollow bore of the shaft connected to the power supply and control unit.

 MMD may differ in that the windings of the coils are made of tape coated with insulation and are made of electrically conductive and soft magnetic material.

The design and operation of the engine are illustrated by drawings, where:
- in FIG. 1 shows one of the MMD variants with an external rotor, consisting of three toroidal magnets mounted in clips, with two electrical units fixed to the stator hollow shaft, and connected to the control and power units through the openings of the hollow shaft;
- in FIG. 2 shows an electrical schematic diagram of an MMD with a control unit consisting of power switches and a power supply;
- in FIG. 3 is a design of an electrical unit comprising a patch board and a radiator, in the slots of which are mounted ribbon coils and rotor position sensors, for example, Hall sensors;
- in FIG. 4 - topology of the circuit board, providing a connection of the coils in the section and the connection of the rotor position sensors with each other and with other blocks;
- in FIG. 5 - diagrams of voltages and currents in electrical units depending on the position of the coil sections and the alternating magnetic field of the rotor.

 The engine contains two magnetic circuits 1 on bearings 2, sitting on the stator hollow shaft 3 and abutting against the ends of the extreme magnets 4. Three magnets 4 are alternated with two electrical units 5 containing a switching board 6 and a radiator 7.

The circuit board 6 electrically connects six tape coils 8 into three paired sections and three position sensors 9, for example a Hall sensor, with the control unit 12. The coil sections 8 are offset from each other by 60 ^o , and the rotor position sensors by 120 ^o . Coils 8 and sensors are installed in the grooves of the radiator 7, which provides heat dissipation and mechanical strength of the electrical unit 5. All magnets 4 are installed in the clips 10, are mechanically connected to each other and to the magnetic cores 1, with the formation of toroidal gaps 11, in the space of which electrical blocks are placed 5 mounted on the hollow shaft 3 of the stator.

 The rows of magnets 4 are installed in the clips 10 in such a way that their alternating magnetic fields are directed towards each other (see Fig. 5) and are closed by magnetic circuits 1, while the magnetic field strength of all magnets 4 is summed up in the toroidal gaps 11.

 When the coils 9 are made of an electrically insulated, electrically conductive tape made of soft magnetic materials, for example permalloy, the magnetic resistance in the toroidal gap decreases and, accordingly, the magnetic field strength in the gap increases. In this case, the engine efficiency increases, its power increases. This is accompanied by an increase in the magnetic field in the working gap 11 and a decrease in the load on the bearings of the motor shaft.

 The outputs of the position sensors 9 through the openings of the hollow shaft are connected to the inputs of the control unit 12, and during the rotation of the rotor they form three groups of control signals of the power switches 14, in the collector circuit of which sections of the coils 8 are connected, connected by other terminals to the power supply 13. In this case, sections of coils 8 in different rows of electrical units are connected in parallel, possibly in series as well as in series-parallel connection of sections. At the same time, we get the opportunity to regulate and control engine parameters.

 The control of the switching sections of the coils 8 makes it possible to change the parameters of the MMD: power, speed per minute and the direction of rotation of the engine.

 MMD proposed design works as follows.

When the voltage of the power source 13 is connected, the rotor comes into rotation, since the proposed combination of the rows of electric blocks 5 and the arrangement of magnets 4 with alternating polarity forms an electromagnetic field strength in the gap 11, which triggers the position sensors 9 and, accordingly, the power switches 14, which create pulsed currents I ₁ , I ₂ , I ₃ in the connected windings of the sections of the coils 8 (Fig. 5).

 In this case, an electromotive force arises between the coils and the magnetic field of the toroidal gap 11, as a result, the rotor of the motor comes into rotation.

 Toroidal magnets 4 installed in the cages 10 due to the magnetic cores 1, provide the formation of a magnetic cushion in the toroidal gap 11, in which two electrical units 5 are placed, the interaction of electric and magnetic fields reduces the load on the rotor bearings.

в зависимости от положения ротора, регулирующего с помощью датчиков положения возникновение в обмотках электродвижущей силы ψ₁, ψ₂, ψ₃ (фиг. 5). Это приводит к возникновению магнитоэлектрических сил в каждом тороидальном зазоре 11, обеспечивающих создание вращающего момента на роторе при автоматическом переключении обмоток катушек 8 в чередующемся магнитном поле ротора двигателя.The flux linkage of the total magnetic field of the magnets 4 and the electric field of the coils 8, when currents pass through them, changes

depending on the position of the rotor, which regulates with the help of position sensors the occurrence of electromotive forces ψ ₁ , ψ ₂ , ψ ₃ in the windings (Fig. 5). This leads to the emergence of magnetoelectric forces in each toroidal gap 11, providing the creation of torque on the rotor when automatically switching the windings of the coils 8 in the alternating magnetic field of the motor rotor.

 From the diagrams of FIG. 5 it follows that the proposed design of the MMD provides a summation of the magnetic fields of several toroidal magnets in the toroidal gap 11 and the electric fields of several electrical units 5. Thus, it becomes possible to obtain a high specific power of the engine, and the electromagnetic cushion of the working gap 11 can reduce the load on the rotor shaft bearings , increasing the reliability of MMD.

 The invention allows to summarize the intensity of magnetic and electric fields in the toroidal working gaps of the engine by dialing the required number of standard electrical units and toroidal magnets and thus obtain the required specific power with a high level of unification of units and parts.

Literature:
1. Auth. testimonial. USSR N 1775807, M.C. H 02 K 23/54, Bi 13, 91.

 2. Auth. testimonial. USSR N 1640797, M.C. H 02 K 23/54, Bi 42, 92.

 3. Patent of Russia N 1813229, M.C. H 02 K 29/06, Bi 16, 93.

Claims (2)

 1. A magnetoelectric torque motor containing a stator with a circuit board and connected in a quasi-ring coil section, a control unit composed of several branches for periodically connecting the sections to a power source, rotor displacement sensors, the terminals of which are connected to the control inputs of the control unit branches, a rotor with a toroidal a magnet with axial magnetization and alternating polarity, characterized in that the motor is equipped with additional magnets abutting against the ends of the extreme magnets of the magnetoproduct odes on bearings sitting on the hollow shaft of the stator, alternating with magnets by electrical units containing a circuit board and a radiator, in the grooves of which are mounted coil sections and rotor position sensors, while all magnets are mounted in cages interconnected with magnets with the formation of toroidal gaps , in the space of which there are electrical units, with alternating magnetic fields of magnets directed towards each other, the conclusions of the rotor position sensors and coil sections in the rows of electrical units connected They are connected in series, or in parallel, or in parallel-series and through the openings of the hollow shaft are connected to the power supply and the control unit.  2. The magnetoelectric torque motor according to claim 1, characterized in that the windings of the coils are made of tape coated with insulation, and are made of electrically conductive and soft magnetic material.

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