SU600669A2 - Contactless dc electric motor - Google Patents

Description

one

This invention relates to electric drives.

Non-contact direct-current electric motors (BDPTs) are known, in the case of impulse stabilization of which the regulator acts on the auxiliary winding circuit of the autogenerator, which periodically turns off and on the sections of the main winding of the motor as the instantaneous speed value changes.

According to the main author. St. No. 479201 is known for a contactless DC motor comprising an electric machine with a rotor position sensor and a switch made in the form of magnetotransistor switches (MTK) connected to the core sections of an electric machine.

The disadvantage of these engines is large ripple speeds.

This is due to the fact that MTKs disconnect the core winding sections not at the moment when current is supplied to the signal circuit of the sensing elements, but with some delay due to the inductance of this circuit. During the lag time, the instantaneous speed value has time to exceed the value set by the stabilizer.

The aim of the invention is to reduce the amplitude of the pulsations of the rotation speed of the rotor of the engine and, consequently, increase the smoothness of its rotation. Goal

is achieved due to the fact that the outputs (or input windings) of the MTC sensitive elements form a series circuit with an executive relay, which is connected at one end to one of the power supply terminals, and through the diodes to those ends of the machine winding sections that are connected to the MTHS in FIG. . 1, 2 are given the diagrams of two variants of the proposed engine, where 1, 2, 3 are the sections of the main winding of the BDPT; 4, 5, 6 - transformers MTK (internal elements of MTK); 7, 8, 9 - additional windings of transformers MTK; S-15 - MTC transistors; 16, 17 - resistors; 18 - speed setting device; 19 is a comparison device; 20 - speed meter; 21 - executive relay of the speed stabilizer; 22-24 - valves; 25, 26, 27 — saturation throttles.

The proposed device is made as follows.

MTKs, each of which is assembled on two transistors (for example, 10 and I) and a transformer (for example, 4), are used to switch the current in sections of the motor winding. Transformers 4-6 function as sensitive elements of a rotor position sensor (DPR) of an electric motor. Additional windings 7–9 of transformers 4–6 MTK are connected in series with each other and through the executive relay 21 of the speed stabilizer and valves 22–24 are connected in parallel to sections 1-3 of the motor core winding. Speed master 18, speed meter 20, comparator 19 and relay 21 are elements of a speed stabilizer and can be made according to various schemes.

The DPR signal element is a permanent magnet mounted on the motor shaft and alternately saturating the cores of transformers 4-6.

The engine works as follows.

When the BDI1 is connected to a power source, its rotor comes into rotation, while the magneto-transistor switches are alternately turned on by the action of the signal element of the PDD under the voltage of the core section.

As soon as the instantaneous value of the speed exceeds the level determined by the speed selector la, the comparison device 1U issues a signal to turn on the relay 21. An electric current flows through the windings Y, B, Y of transformers of all Ml K, due to the EMF of rotation in sections i, 2 , with the engine's engine core. This current, flow through sections i, /, 6, causes the creation of a braking moment and causes saturation of the transformer cores 4, 5, b, which leads to the shutdown of all MlK, i.e., to disconnect all sections from the power source. The instantaneous speed of the engine begins to decrease and at a certain value of the relay 21 turns off, the circuit is wired, and, U is de-energized, the braking torque disappears, and the CIM is again alternately connected to the source of the core section of the winding signal. The engine, having developed a torque, accelerates. When the relay 21 is closed, the section is again disconnected from the source, etc. Thus, the instantaneous velocity value will pulsate with a certain amplitude relative to its predetermined average value.

Although when the relay is closed, the shutdown of all MTCs occurs with a delay due to the inductance of the winding circuit 7,

8, 9, the instantaneous rotational speed due to the action of the brake torque noted above will not only not increase, but may even decrease, the latter depends on the ratio of torque and braking torque developed by the currents of all sections of the motor winding in the period from the moment the relay 21 is closed to the moment it is turned off all MTK.

Consequently, the amplitude of the velocity pulsations will be significantly less than in the case when the specified engine braking is absent.

Thus, the connection through the valves 22-24 of the signal outputs (windings 7, 8, 9) of the MTC transformers to the core sections of the LDPG core reduces the amplitude of pulsations of instantaneous speed and, consequently, increases the smoothness of the rotor rotation.

The circuit shown in FIG. 2, works in the same way as described above. The only difference is that the additional windings 7, 8, Y are located on sensitive elements 25, 26, 27 DPR, which are made in the form of chokes.

It should be noted that in the case when the DPR sensitive elements are chokes connected to all or only part of the primary or secondary windings of MTK transformers, additional windings 7, 8, 9 are more comfortable to locate on MTK transformers located in the BDPT switch.

Claims (1)

Invention Formula Contactless DC motor for auth. St. No. 479201, characterized in that, in order to reduce the amplitude of the velocity pulsations, the outputs or input windings of the sensitive elements of the magnetotransistor switches form a series circuit with an actuating relay that is connected to one end of the power supply terminals and the other diodes to those section ends winding machines that are connected to magnetotransistor keys. L.-L. 25 P A II12 26 13 JZIJL