The invention relates to electric machines, in particular to generators/motors, both linear and rotational.
The principles of operation of linear and rotational generators/motors are similar.
The principles of operation of these devices are shown in
Bayaliyev Universal Generator/Motor can be both linear and rotational that differ from each other only by the type of moving trajectory of the movable magnet core.
Understanding of a linear generator/motor device can be obtained if we mentally cut the stator (1) and the rotor (4) with the windings (2) and (3) of a conventional asynchronous motor along the rotational axis and unfold them into a flat plane as shown in
The resulting “flat” design is the basic circuitry of a linear motor. When the stator windings 2 of such a motor are connected to an alternating current network, a magnetic field will be formed, the axis of which will move along the air gap with the speed V proportional to the frequency of the supply voltage f.
Typically, known linear generators/motors have two types of mutual arrangement of magnets and windings.
Since the windings will alternately (i.e., not simultaneously) enter the operating zones of magnets of different orientations, the function of the magnetic flux transition ϕ from the magnitude of displacement in such design will look as follows.
Δϕ=f(ΔX)
The obvious disadvantage of the design is the necessity of using sliding contacts (not shown in the figure) to conduct electricity from the coils located on the moving rod.
For a coil in the variable magnetic field, Faraday's law can be noted as follows:
E=−Δϕ/Δt, where
E—electromotive force acting along an arbitrarily chosen circuit,
ϕ—magnetic flux through the surface limited by this circuit,
t—time of the magnetic flux transition.
Alternate magnetic flux transition in traditional designs means that the magnetic field in the winding changes (increases or decreases) in one direction and then in the opposite. This leads to a slow transition in the magnetic flux inside the winding and is the main disadvantage of typical designs currently in use. A second disadvantage is a large number of magnets and windings that leads to an increase in the cost of such designs. A third disadvantage is that not all magnets and windings work simultaneously during the entire reciprocating motion cycle.
The objective of the claimed invention is to increase the generated EMF, minimize the number of used magnets and windings, and maximize their utilization during the entire generation cycle.
For these purposes, a constructive arrangement of the magnet and windings in a separate base element on a fixed magnetic core is used to create an opposite magnetic flux transition in the windings. The base element consists of one magnet and two windings as will be shown later in the description.
The design uses a base element (14) that includes a fixed magnet core (8) with a magnet (10) mounted at the midpoint (9) of the magnet core. There are 2 windings (11) at the edges of the fixed magnet core. The movable magnetic core (12) has a reciprocating motion (motion direction is item 13) on ball-bearings (not shown in the figure). The direction of the magnetic flux through the left and right windings is shown by blue arrows.
As it is shown in
A shift of the movable core (12) to the left or right by ΔX as shown in
Δϕ=f(ΔX)
The windings are connected in series to form a single winding.
The total transition of the magnetic flux in a single winding will be:
Δϕ=f(ΔX)−(−f(ΔX))=2f(ΔX), thus increasing by a factor of 2 compared to typical designs.
In contrast to typical designs, the movable magnet core (rotor) does not generate any magnetic field but is a passive element like a ferromagnetic core in a solenoid. It switches the magnetic lines through the magnet and windings, reducing the magnetic resistance between the magnet and the right winding or the magnet and the left winding.
For large displacement values, a movable magnetic core with protrusions (prongs) is used, which allows providing transitions of magnetic fluxes at any value of displacement. This design is shown in
In the case of using a ring magnet and two windings, it should be noted that the magnetic lines are arranged as shown in
The basic element will look like in
The principle of operation of this design is similar to the device shown in
In order to increase the excitation of the magnetic field, an excitation winding (20) can be placed in the area where the permanent magnet is located as shown in
With a magnetizing winding, the use of a permanent magnet is not necessary if a hard magnetic carbon steel material (21) that retains residual magnetization is used as shown in
Bayaliyev Universal Generator/Motor is a reversible machine and can operate in a motor mode as similar machines. In the motor mode, the alternating voltage must be applied to the generating and magnetizing windings through a generator with a control unit, shown in
To increase the power of the Bayaliyev Universal Generator/Motor in both the generator and the motor modes, it is possible to install not one but several (two or more) basic elements with the same movable magnetic core as shown in
f=N/60, where
N is the number of rotor revolutions per minute (rpm).
For generators with p pole pairs, the frequency of current at n/60 rpm will be p times greater than for a two-pole generator, i.e.
f=pN/60
Hence, the formula for determining the rotor rotation rate will be as follows:
N=60f/p
To reduce the rotation rate of the generator, at a constant current frequency f, for example in wind turbines, it is necessary to use multi-pole designs, which increases their cost as it is necessary to use from 15 to 90 pairs of poles.
In such designs, as well as in traditional linear generators, the windings will alternately (i.e., not simultaneously) enter the operating zones of magnets of different polarization and the function of the magnetic flux transition ϕ vs the magnitude of displacement will look as follows:
Δϕ=f(Δβ), where β is the rotor rotation angle.
The objective of the claimed invention is to increase the generated EMF, reduce the generator rotation rate, minimize the number of used magnets and windings, and maximize their utilization during the entire generation cycle.
Δϕ=2f(Δβ)
The rate of magnetic flux transition will be twice of the currently available analogues.
To increase the power and achieve a more uniform distribution of the load, it is also possible to use two or more base elements with a single movable magnetic core (rotor) as shown in
The output frequency will depend on the number of protrusions (prongs) on the moving element by the formula:
f=N*Nprong/60, where
N—number of rotor revolutions per minute:
Nprong—number of prongs on the rotor.
The formula shows that to increase the output frequency of the generator it is enough to increase the number of prongs in the movable magnetic core, and, therefore, the rotor speed can be reduced by the same amount that is very important for low-speed generators used at the wind and hydropower plants. In particular, the rotational speed of the shaft of the device shown in
N=60f/Nprong=60*50/20=3000/20=150 rpm
Bayaliyev Universal Generator/Motor with rotational motion of the movable magnet core is a reversible machine and can operate in a motor mode. Using three basic elements, a three-phase synchronous motor can be implemented with a typical set of rotation controls.
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/KZ2019/000014 | 8/7/2019 | WO |