JPS6220789B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a self-starter having a permanent magnet rotor, a stator with two windings, and an electronic switch element connected in series with the windings to an operating DC voltage. The present invention relates to an electric motor control device.

In self-starting electric motors with known control devices of this type, the rotor can assume various rest positions. However, the permanent magnets of the rotor always tend to carry the rotor to a position such that the shortest distance is formed between the stator irons and the rotor permanent magnets, which are placed opposite this rotor. . In other words, the position where the air gap between the rotor and stator is minimized for the magnetic flux that flows out from one magnetic pole of the rotor's permanent magnets, then passes through the stator iron piece and flows into the other magnetic pole. , the rotor tends to be carried away. In this position, if the stator poles are symmetrically constructed, the resulting rotor torque when the stator is magnetized is equal to zero.

When the rotor is in the neutral position, the rotor's neutral axis overlaps the stator's neutral axis. By creating an asymmetrical magnetic field distribution between the rotor and the stator, for example by means of additional permanent magnets on the stator, the following is achieved: That is, the rest position of the rotor does not overlap with the neutral position and is at most an acute angle (approximately 5).
This means that it is shifted from the middle position. This provides a predetermined starting direction.

In this type of motor, the stator magnetic field needs to switch polarity every half rotation of the rotor. However, due to the inherent inductance of the stator windings, this polarity switching does not occur as quickly as switching of the switch elements. Therefore, if the switching point of the switch element is set so that switching begins exactly at the moment when the rotor passes through the neutral rotational angular position, the switching of the polarity of the stator field only ends when the rotor is at this point. This occurs after the rotation angle position has already been passed. As a result, the rotor is
From the moment of passing through this neutral angular position until the end of the polarity change of the stator field, the rotor is subjected to a counter-torque that brakes it. Therefore, efficiency decreases.

The object of the invention is to propose a control device in which the efficiency of the motor is improved and at the same time it is ensured that the motor can be started from any angular position.

This problem is solved by the present invention as follows. A control device for a self-starting electric motor having a permanent magnet rotor, a stator with two windings, and an electronic switch element connected in series with the windings to an operating DC voltage. The transmission input side of the control circuit is provided with an output signal of a detection device for detecting the rotational angular position of the rotor in a stationary state, and further provided with a measuring element for identifying rotation or non-rotation of the rotor. , when the rotor rotates, the output signal from the measuring element controls the control input side of the control circuit, and the output signal from the detection device passes through the control circuit and is supplied to the transmission input side of the gate circuit. In this case, the gate circuit generates switch control signals of mutually opposite polarity to the electronic switch element based on the supplied signal, while when the rotor is not rotating, the gate circuit generates switch control signals of opposite polarity to the electronic switch element. Another output signal controls the control input of the control circuit such that the output signal from the detection device is blocked from passing through the control circuit, in which case the starting signal from the pulse generator is controlled by the gate. a control input of the circuit and an input of the control circuit to open the gate and operate the control circuit for a predetermined period of time defined by a timer circuit, the gate circuit receiving the supplied start signal; The control circuit generates switch control signals of opposite polarity to the electric switch element based on the above-mentioned conditions, and after the predetermined time has elapsed, the timer circuit causes the control circuit to pass the pulse from the detection device to the input side of the gate. This is what I did.

This technical configuration ensures that the polarity switching of the stator field begins already before reaching the neutral angular position, and that when this neutral angular position is reached,
It is ensured that polarity switching is at least substantially finished. The stator magnetic field therefore acts substantially the same in the desired direction of rotation when the neutral rotational angular position is reached, and does not exert a significant counter-torque before reaching the neutral rotational position. Therefore, a uniform torque is generated during driving.

However, the normal switching point is placed before the neutral position by the value of the preset angle, so when the motor is switched off, the rotor is behind the normal switching point and the stator neutral axis and rotor Difficulties arise if the vehicle stops at one of the critical angular positions somewhat in front of the neutral angular position where the neutral axis overlaps. When the motor is switched on in this type of rotational angular position, the stator magnetic field drives the rotor in the opposite direction. Immediately thereafter the normal switching point is passed in the opposite direction of rotation. This causes the stator magnetic field with switched polarity to brake the rotor and drive the rotor in the desired direction of rotation. In this case the switching point is immediately passed again. The moment of inertia of the rotor causes the rotor to start again with polarity switching of the stator magnetic field and an asymmetrical magnetic field distribution (formed by an additional permanent magnet) and a neutral rotation in the desired direction of rotation despite the load. If the rotational speed of the rotor is not high enough to drive beyond the angular position, the rotor is immediately driven again in a direction opposite to the desired direction of rotation, i.e. in the opposite direction. As a result, the rotor makes a reciprocating pendulum motion about the rotational angular position where the polarity of the stator magnetic field is switched. This kind of pendulum movement is avoided by the technical arrangement of the invention.

That is, when the rotor stops at the aforementioned critical position, the control circuit is activated. As a result, the rotor starts against the desired direction of rotation and passes through the normal switching point where the switching action is blocked. In this case, the rotor can rotate in the opposite direction, as far as possible within a control time that depends on the load. After the end of the control period, the stator magnetic field is switched in polarity according to the instantaneous angular position of the rotor, and the rotor is braked and started in the desired direction. The rotor then has to travel in the correct direction again through a larger angle of rotation until the normal switching point is reached. The rotor thus obtains a sufficiently high rotational speed to overcome the counter-torque and reach a neutral position in which the stator magnetic field acts further in the desired direction of rotation due to the instantaneous polarity. The rotor is therefore driven from the critical angular position of stop in the opposite direction, initially through an angle greater than the aforementioned preset angle, and thereafter in the desired direction without pendulum oscillations.

According to the invention, each start-up of the motor begins with a control time from the moment of switching on, so that the switch state of the switch element corresponding to the control signal in the critical rest position is forced.

In this way, the intervention of the control circuit 14 shown in FIG. 1 does not require a complicated adaptation to the predetermined starting position. In the present invention, the rotor initially rotates in the opposite direction, even from many starting positions in which it would conventionally start in the desired direction of rotation. However, this results in a very simple circuit.

In the starting rotation angle region which is not at one of the critical positions, the switch state of the switch element forcibly set by the control circuit 14 and the switch state of the switch element requested by the detection device match. In the angular range of rotation of the part, the rotor immediately rotates in the predetermined direction.

In the other rotation angle region where the switch state of the switch element requested by the detection device during the control time for the control circuit 14 and the switch state of the switch element forcibly set by the control circuit 14 do not match, the rotor initially rotates in the opposite direction.

A signal of a predetermined duration is generated in the control circuit 14, which signal is used to derive the switch signals Sa ₁ , Sa ₂ instead of the control signals S ₁ , S ₂ during start-up. This simplifies the configuration of the control circuit 14.

Switch signals Sa ₁ and Sa ₂ are supplied to electronic switch elements 4 and 5 via gate circuit 13 . The gate circuit 13 is normally conduction-controlled as a function of the rotation signal A=0, and at the moment of starting and when the rotor is blocked, it receives a relatively short pulse generator 25 which is independent of the usual rotation signal transmitter. Paddle start signal B=0
is supplied alternately as a conduction control signal and a stop signal B=1, which is longer than this start signal, as a cut-off signal. The stop signal B=1 is blocked by the normal rotation signal A=0 in the case of normal drive. in this case,
When the motor is switched on, a first starting signal B=0 is supplied from the pulse generator 25 and a first starting is attempted. If the motor does not start, the switch signals Sa ₁ and Sa ₂ to the electronic switch elements 4 and 5 are supplied to the pulse generator 2 following this starting signal B=0.
It is interrupted by the gate circuit 13 during the duration of the stop signal B=1 of 5. Only with the occurrence of the next starting signal B=0 is a second starting attempted. When the motor rotates, the drive continues under control based on the normal rotation signal A=0. If the rotation of the rotor is stopped during driving, the normal rotation signal A = 0 disappears, and the motor is activated by the stop signal B = 1 of the pulse generator 25.
is blocked by When the next starting signal then appears, starting is automatically attempted again. In this way, a starting attempt is made only for a short time after a relatively long rest time. As a result, the relevant stator windings 2, 3 or the relevant switch elements 4, 5 are not overloaded. When the rotation block automatically disappears, the motor starts automatically again. In this case, as soon as the motor rotates normally, the normal rotation signal generator performs a cut-off control of the signal of the pulse generator 25, which is independent of this generator and is independent of the pulse generator.

The control signals S ₁ , S ₂ from the detection device 6 are simply fed to the gate circuit 13 via the input 32 of the control circuit 14 .

Furthermore, the control input 15 of the gate circuit 13 is connected to the control input 28 of the control circuit 14, with a start signal B=0 and a stop signal B=0 at both inputs.
1, and a normal rotation signal A=0. In this case, the control circuit 14 initially has its control input 2
It responds only to signals applied to 8. This simplifies the circuit considerably.

Since the control circuit 14 is responsive to the leading edge of the rotation signal, when the motor is connected, the generation of the start signal initiates the control time for the control circuit 14;
Furthermore, it is ensured that the connection time of the control signal to the control circuit 14 does not depend on the connection time of other signals.

In the event of a reaction of the control circuit 14, the control signals S ₁ , S ₂ from the detection device 6 are prevented from acting and the gate circuit 13 is switched to a predetermined switch state, so that the desired switch signals Sa ₂ , Sa ₁ becomes significantly easier to control.

The duration of control over the control circuit 14 is made shorter than the start signal. This ensures that the correct starting condition is set again immediately after the end of the control time for the control circuit 14 in order to drive the rotor in a predetermined direction of rotation.

The control circuit 14 has a timing element 29 and a coupling element 31 controlled by the timing element 29, which coupling element 31, depending on the output signal of the timing element 29, generates the control signals S ₁ , S ₂ of the detection device. is cut off and the gate circuit 13 is switched. After the control time for the control circuit 14 has expired, the coupling element releases the gate circuit and the control circuit back to their original state. This greatly simplifies the construction of the control circuit 14.

Furthermore, when the timing element 29 is triggered as a function of the signal applied to the control input 15 of the gate circuit 13, the control circuit 14 controls the transmission input 12 of the gate circuit 13. This makes it possible to easily simultaneously trigger the timer and connect the motor in response to the starting signal B=0.

Furthermore, the time element 29 is a differential RC-element 52,5.
1, and a switch stage 30 is provided between the coupling element 31 and the timing element 29. This causes the switch stage 36 to switch more precisely to the leading edge of the trigger pulse. The duration of this new switching state of the switch stage 36 does not depend on the extinction of the trigger pulse, but only on the activation time of the limiting element. This ensures that the duration of the starting signal B or the duration of the normal rotation signal A=0, which overlaps this duration, does not influence the control time for the control circuit 14.

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows a control device for a brushless DC motor having a two-pole permanent magnet rotor 1 and two stator windings 2, 3. The stator windings are each connected in series with an electronic switch element 4 or 5 to an operating DC voltage U _B . The electronic switch elements 4 and 5 are controlled to be conductive by the 1- signal, and are cut off by the 0- signal. The conversion device 6 has a detector 7 for detecting the rotational angular position of the rotor 1 and a pulse shaper 8 connected downstream of the detector 7 . The detector 7 is designed, for example, as a coil with a saturable iron core. The detector supplies a signal in response to a change in the inductance of a semi-annular ring plate R of magnetizable metal, for example, which is fixed to the rotor 1 when it passes by. The magnitude of this signal takes on one of two values for each half revolution of the rotor. This signal is controlled by the pulse shaper 8.
It is converted into a repetition frequency of S ₁ and S ₂ . Its impact factor (pulse duration/cycle duration) is 1:2. For this purpose, the pulse shaper 8 has an oscillator 10, which is turned on and off by signals from the detector, and a converter 11 connected downstream thereof.
The control signals S ₁ , S ₂ are led via a control circuit 14 to the transmission input 12 of the gate circuit 13 . The other input 15 of the gate circuit 13 is used as a control input. The gate circuit 13 has coupling elements 16, 17 in the form of OR elements each having an inversion stage on the transmission input side. The control inputs of the coupling elements 16, 17 are connected to each other. Furthermore, the output side of the coupling element 16 is connected to the transmission input side of the coupling element 17. The outputs of the coupling elements 16, 17 directly form the outputs of the gate circuit 13 and are connected via a NOT element 18 or 19, respectively, in the form of an inverting amplifier, to the control input of the switching element 5 or 4. control input side 15 and coupling element 16,
A common NOT element 20 is connected between the control input side of 17 and the control input side of 17. This NOT element constitutes a NAND element together with coupling elements 16 and 17 which are connected downstream.

Connection point 21 between stator winding 2 and switch element 4
is connected to the input side of the comparator 23 via the pulse repetition frequency measuring element 22. This comparator has the function of a NAND element. A reference voltage source 24 is connected to the other input side of the comparator 23.
The output signal A of the comparator 23 and the output signal B of the pulse generator 25 are combined by an AND element 26. The output signal of the AND element 26 is the output signal of the NOT element 27.
to the control input 15 of the gate circuit 13 and to the control input of the control circuit 14. The control circuit 14 has on its input side 28 a timing element 29 and a switch stage in the form of a NOT element 30 connected downstream thereof. This NOT element acts on the control input side of the coupling element 31, in this case an AND element, which acts as a gate. The transmission input side of this coupling element 31 becomes the transmission input side 32 of the control circuit 14.

A permanent magnet 33 is installed in the stator as follows, that is, when no current flows through the stator windings 2 and 3, the neutral axis 34 of the rotor 1 and the neutral axis of the stator are aligned. so that rotor 1 normally takes a position where it does not
It is provided. The detector 7 is the neutral axis 35 of the stator.
It is located on the line of On the other hand, the ring plate R is provided in such a way that for a given or desired direction of rotation, indicated by the arrow P, it rotates around the moment when the end of the ring plate R passes the detector 7. Every time the child 1 rotates approximately half a rotation, the switch element 4,
The switch is provided so that switching (switching action) of 5 is performed. N and S indicate the north or south poles of the rotor 1 or the permanent magnet 33. At the normal switching point, the neutral axis 34 of the rotor 1 is in front of the position shown.

In order to explain the operation of the control device shown in FIG. 1, it is first assumed that no control circuit 14 is provided, that is, that the transmission inputs 32 and 12 are directly connected.

Pulse generator 25 when the motor is connected
generates a starting signal B=0 which is longer than the motor starting time but relatively short. A stop signal B=1, which has a significantly longer duration than this signal, is interposed between this start signal and the next start signal. In the resting state, no positive pulses yet appear at the persistence point 21. The same applies if the current in the stator windings is interrupted during rotation. The pulse repetition frequency measuring element 22 therefore supplies a 0- signal to the comparator 23. As a result, a non-rotating signal A=1 appears at the output of this comparator. Under this condition, as long as the starting signal B=0 remains, the control input 15 of the gate circuit 13 is supplied with a 1- signal due to the inversion by the NOT element 27. This 1- signal controls the conduction of the gate circuit 13. As a result, one of the two switch elements 4 or 5 has one on the input side 12.
- Depending on whether a signal is applied or a 0- signal is applied,
1 - Signal is provided. If the rotor 1 is initially placed in a rotational angular position such that the control signal S ₂ , that is, the 0-signal appears, a 1-signal appears at the output of the coupling element 16 . This 1- signal is NOT
Via element 18, a switch signal S _a2 in the form of a 0-signal is applied to the control input of switch element 5, placing it in the disconnected state. On the other hand, when the coupling element 17 sends out a 0- signal and this signal is supplied to the control input side of the switch element 4 as a switch signal _a2 in the form of a 1- signal via the NOT element 19, this switch Controls conduction of the element. However, when the control signal _S1 , ie the 1- signal, appears with the rotor 1 at rest, the switch element 5 is first turned on. The motor is started by controlling the conduction of one of the switch elements 4 or 5. As a result, a positive pulse also appears at the persistence point 21. The value of this pulse repetition frequency is such that the pulse repetition frequency measuring element 22 delivers a measurement signal that is equal to or greater than the reference voltage delivered by the reference voltage source. Therefore, comparator 23
A 1- signal is applied to both inputs of.

Therefore, the output side of the comparator changes from the non-rotating signal A=1 to the normal rotating signal A=0, and the AND element 26
is blocked without depending on B=0 or B=1. That is, the 1- signal is still supplied to the control input 15, and this 1- signal continues to control the conduction of the gate circuit 13. Therefore, while the motor is rotating, this gate circuit outputs the switch signals S _a1 , S _a2 , _a
1 , control signals that are continuous at intervals shorter than _a2
Pass through S ₁ and S ₂ . As a result, switch element 4,
1- signals are alternately supplied to the control input side of 5 at the timing of this control signal. Correspondingly, the frequency of the pulse at the persistence point 21 is also kept high.
As a result, the measurement signal on the output side of the pulse repetition frequency measuring element 22 is kept at a 1-signal, and the output signal A from the comparator 23 is kept at the normal rotation signal A=0.

However, if the rotation of the motor or rotor 1 is prevented, for example due to an overload, the repetition frequency of the control signals S ₁ , S ₂ is no longer emitted. Therefore, connection point 21
The pulse repetition frequency disappears. This causes a non-rotation signal A=1 to appear. As a result, starting signal B
=0 is again passed through the AND element 26,
Starting is attempted one by one with each starting signal until the rotation blocking effect disappears automatically, for example, and the motor resumes steady rotation. However, for example, the duration of the starting signal B=0, about 0.28 seconds, is significantly shorter than the entire period duration of the signal B, about 22.4 seconds, so the starting signal B=0 in the state where the motor is prevented from rotating causes the motor to No damage will be caused. In the case of rotation prevention, 0- is applied to the input side 12 of the gate circuit 13 during that time.
When the rotor is placed in such a position that the signal S ₂ is applied, the stop signal B=1 causes the current in the stator winding 2 to be switched on and off repeatedly, so that a positive pulse appears at the sustain point 21. However, this positive pulse has a low frequency of the same value as the start/stop signal B.
As a result, the pulse repetition frequency measuring signal does not exceed the reference voltage, so that no rotational signal A=0 is normally delivered at the output of the comparator 23.

The measurement of the pulse repetition frequency of the positive pulse appearing at the duration point 21 must be carried out on the basis of the measurement time unit. Therefore, the selection of the timer element provided in the measuring element 22, which determines the measurement time unit, is changed to the normal state by the generation of the normal rotation signal A=0. is converted into a signal and the starting signal B
=0 is guaranteed at the same time before being cut off.

The switching points of the switch elements 4 and 5 are placed somewhat before the neutral rotation angle position where the neutral axis of the rotor 1 and the neutral axis of the stator coincide. At this switching point,
The end of the ring plate R and the neutral axis of the stator coincide. The advantage of this is that when the rotor has just passed the neutral angular position, due to the natural time delay,
This polarity switching can be started at an appropriate time so that the polarity switching of the stator magnetic field has already been completed. The torque generated by the stator magnetic field therefore always acts in the desired direction of rotation - in this case in the direction of the arrow - over a wide angular range during the drive of the motor. If the switching of the switch element takes place just at the neutral angular position, a braking torque will act on the rotor from this point until the end of the polarity switching of the stator poles.

However, this selection of the position of the switching point does not mean that the rotor 1 is in the rotational angular position shown in FIG. When the engine is stopped at an angular position between the corresponding positions, it can cause difficulties during starting. In this position, when the motor is switched on, a first starting signal B=0 creates a stator field of a polarity that immediately drives the rotor 1 in a direction opposite to the desired direction of rotation P until the switching point is reached. , after which a magnetic field is created which again brakes the rotor and drives it in the opposite direction of rotation, ie the desired direction of rotation. In this case, the switching point is immediately passed again, so that the stator field is switched in polarity again before the neutral rotation angle position is passed. This is because the angle of rotation from the reversal point of the rotor back to the switching point in the direction of the desired direction of rotation P is too small, causing the rotor to be forced to move until it reaches the neutral rotation angle position due to a new polarity switch of the rotor magnetic field. This is because sufficient rotational speed cannot be provided to overcome the acting reverse torque. In this case, the reverse torque is further increased by the permanent magnet 33. As a result, rotor 1 is
It usually does not rotate, but always makes a reciprocating pendulum motion. However, the above considerations apply only when the control circuit 14 is not provided, as described above.

Pendulum movements of the rotor 1 are avoided by incorporating the control circuit 14. For the sake of explanation, it is assumed again that the rotor 1 is stopped at the position shown in FIG. As a result, a 0-signal S ₂ , a non-rotation signal A=1 and a stop signal B=1 appear. A 0-signal therefore acts on the control input 15 of the gate circuit 13, so that both switch elements 4, 5 are forced to receive a 0-signal _a1 or S _a2 . On the other hand, when the first starting signal B=0 occurs, both input sides 15, 2
8 is supplied with a 1- signal. As a result, the gate circuit 13 is controlled to be conductive, and at the same time the timer element 29 is triggered. As a result, this timing element generates a 1- signal during its operating time. This 1- signal is
The signal is inverted to a 0 signal via the NOT element 30 and the AND element 31 is cut off. There is already a 0-signal on the input side 32.
Since S ₂ is added, the 0- signal remains on the output side of the AND element 31. However, the signal state at the output of the gate circuit 13 changes due to the application of the 1- signal at the control input 15. As a result, signals S _a2 and _a2 appear. Therefore, the switch element 4 is controlled to be conductive, while the switch element 5 is placed in a cut-off state. The stator magnetic field formed by the current flowing through the stator winding 2 therefore has the direction shown in FIG. Therefore, this magnetic field moves the rotor 1 from the position shown in FIG.
It is driven in a direction opposite to the desired rotation direction P.
However, the duration of the starting signal B=0 and the shorter operating time of the timing element 29 are such that the rotor 1
is chosen so long that it passes through the switching point during the operating time of the timing element 29. In this case AND
Since the element 31 is further kept in the cut-off state during the operating time of the timer element 29, no switching of the switch signal takes place even when the control signal _S1 appears. As a result, the rotor 1 rotates against the desired direction of rotation P, well beyond the switching point, until the operating time of the timing element 29 has expired. When the operating time of the time element 29 ends, a 1- signal is applied to the control input of the AND element 31. As a result, this AND element is rendered conductive and the control signal S ₁ still applied to its other input 32 is rendered conductive. Starting signal B=
0 and therefore the 1- signal at the control input 15 of the gate circuit 13 still persists, so that the switch signals are switched to S _a1 and _a1 . As a result, the switch states of switch elements 4 and 5 also alternate so that the stator magnetic field is switched in polarity as shown in FIG. Therefore rotor 1 is braked,
Finally, starting is started again in the desired direction P. This provides the rotor with a relatively large starting rotation angle until the switching point is reached again and thus the neutral rotation angle position, so that the rotor can reach significantly higher rotational speeds. Therefore, the rotor is
In the case of passing the switching point, the rotor passes through the switching point and the neutral angular position, even if the stator field is again formed with the opposite polarity. Therefore, the stator magnetic field still exerts some braking force until it passes through the neutral rotation angle position, but
After passing through the neutral rotation angle position, the rotor is driven in a desired rotation direction P (FIG. 5). The starting signal B=0 continues for at least one half turn in the direction P until the next switching point is reached. However, the rotational speed of the rotor is also increased significantly in the meantime. Therefore, element 22~
A normal rotation signal generator consisting of 24 reacts by sending out a normal rotation signal A=0 and assumes the holding of the 1-signal at the control input 15 of the gate circuit 13. In this way, it is ensured that once the motor has been correctly started, the timing element 29 will not be triggered again by the normal rotation signal A=0 or the next starting signal B=0.

The rotor 1 is moved from a rotation angle position where the rotation angle is sufficiently large until the south pole S of the rotor 1 approaches the permanent magnet 33 (FIGS. 3 and 4) and reaches the switching point 35.
When starting, in addition to the non-rotating signal A=1, first (in the stationary state) a control signal S ₁ for the correct direction of rotation P appears. (It should be pointed out here that the polarity of the stator field shown applies for the shown rest position of the rotor 1 in the uncontrolled case.) Then the starting signal B=0 triggers the timer 29 and therefore
The AND element 31 is cut off, and the gate circuit 13 is controlled to be conductive at the input side 15. Therefore, the switch signal is switched from _a1 to _a2 , while the switch signal S _a2 remains unchanged. Therefore, the current injected into the stator winding 2 thereby creates a stator magnetic field such that the north pole is at the left magnetic pole of the stator. The rotor 1 is then (initially) started again against the desired direction of rotation P. However, when the neutral position is reached, the direction of the magnetic field of the stator does not change, and this is before the end of the operating time of the timing element 29, so that the direction of the torque applied by the stator is reversed.

As a result, the rotor rotates further in the desired direction due to the control signal S ₁ still lasting at the end of the operating time of the timing element 29. Starting therefore begins from this rest position with a slight reverse rotation also of short duration. But next, the motor has a permanent magnet 33
It rotates further in the desired direction of rotation under the action of , and no pendulum movement persists during start-up. In the case of starting from other rest positions, the rotor also does not undergo pendulum movements or rotational oscillations. On the other hand, if the start-up starts from the angular position shown in FIGS. If located in the center of the stator pole pieces, rotor 1
is driven further in the correct direction P without reversing.

If the additional permanent magnet 33 were not provided, the permanent magnet rotor 1 would assume one of the two neutral positions when the motor was switched off, i.e. when the stator was demagnetized. This is because the magnetic poles of the rotor 1 are oriented towards the region of maximum specific mass.
However, the permanent magnets 33 cause the rotor 1 to assume either the position shown in FIG. 1 or the position shown in FIG. However, the position shown in FIG. 3 is often passed through. This is because the inertial force of the rotor 1 rotating by inertial force and the magnetic force have the same direction at this position. As a result, Olow takes the position shown in Figure 1. In this position, if the control circuit 14 were not provided, there would be a risk of pendulum movement and the motor would not start.

If the permanent magnet 33 is polarized in the opposite direction to that shown, the same starting characteristics can in principle be obtained with the circuit arrangement of FIG. In this case, the control input side 28 of the control circuit 14 is connected not to the input side 15 of the NOT element 20 of the gate circuit 13 as in the case of FIG. 1, but to the output side, and the coupling element 31' acts as an OR element. Furthermore, the polarity of the timing element 29' is opposite to that of the timing element 29. As a result, this timer is triggered by a 0 to 1 jump change and delivers a 0- signal throughout its operating time. On the other hand, the other circuit parts of the control device shown in FIG. 1 do not need to be changed.

Each of the above-mentioned signals will be briefly explained. In FIG. 1, signal A is an identification signal indicating whether or not the motor is rotating. A signal A=1 indicates that the motor is stopped, and a signal A=0 indicates that the motor is rotating. These values of signal A are compared with square wave signal B, in which case when signals A and B are both equal to 1, a signal 1 is output from comparator 26. This signal 1 is inverted in an inversion stage 27 so that a signal 0 is present at the input 15 of the gate circuit 13. However, as time elapses, depending on the pulse generator 25, the signal 0 appears at the input of the comparator 26.
is added. As a result, the short pulse width starting pulse B=0 is sent to the gate circuit 1 as signal 1.
It joins the input side of 3.

On the other hand, when the motor is rotating, signal A
always has the value 0. A signal 0 therefore always appears at the output of the comparator 26, so that the gate circuit 13 always remains open during rotation.

The A pulse and B pulse that generate the starting signal or actuation signal are the signals generated from the detector 7.
Determine whether S ₁ and S ₂ should be passed through the gate circuit. The control signals S ₁ , S ₂ pass through the gate circuit 13 via the input 12 without being themselves changed. This gate circuit has an inverting stage 16, 17 with two outputs. At this output, signals which are inverted with mutually opposite polarity are produced for the control of both circuit elements 4, 5.

A signal is supplied to the control circuit 14 of the present invention at the same time as the gate circuit 13 . This control circuit determines whether a given one of the two switching signals S ₁ or S ₂ is to be held at the output of the control circuit 12 for a duration defined by the timing element 29 . In the actual case, signal S ₂ is retained.
For this purpose, a 0-signal appears for a short time at the input of the gate circuit at each start-up. Therefore, the same transistor is always connected. As a result, a pendulum movement of the motor is avoided when the motor is switched on again in a predetermined critical holding position.

FIG. 8 shows a more detailed circuit configuration of a part of the control device shown in FIG. In this case, switch elements 5, 4
are flywheel diodes 39 and 4, respectively.
Transistor 3 connected in parallel with 0 having opposite polarity
It has 7,38. A controlled oscillator 10, which is switched on and off by magnetic field-dependent pulses of the detector 7, oscillates at a frequency of approximately 100 kHz in the switched-on state. Post-connected converter 11
generates a control signal from the envelope of oscillator vibration that is turned on and off depending on the rotation speed of the rotor 1. Switch signals for transistors 37 and 38 are extracted from this control signal. For this purpose, the converter 11 has on its input side a smoothing circuit consisting of a coupling capacitor 41, two diodes 42 and 43 forming a half-wave rectifier, a resistor 44 and a capacitor 45 connected in parallel, and an output resistor. 46
has. Coupling elements 16 and 17 of gate circuit 13
has two transistor-switch stages that are push-pull connected. The NOT element with transistor 47 is common to both transistors.
Transistor 47 is connected in series with a respective further transistor 48 or 49 via a resistor in each case. The output side of the collector side of the transistor 48 is connected to the base of the transistor 49. Therefore, if a 0- signal is applied to the control input 15 of the common transistor 47 and this transistor is switched off, the transistors 48, 49
Almost no current flows. As a result, both transistors 48, 49 deliver a 1- signal on the output side. This 1-signal is inverted by NOT- elements 18 and 19, and is therefore supplied to transistors 37 and 38 as a 0-signal, which is a cutoff signal. NOT element 27 has a transistor 50 which is also connected as an inverting amplifier.

The timing element 29 is the capacitor 5 in the input branch.
1 and a resistor 52 with a diode 53 connected in parallel. The diode 53 is the timing element 29
The output side of the terminal is connected to ground (0). As a result, the connection between capacitor 51 and resistor 52 acts as a differential RC element. NOT-element 30 includes transistor 54 .

Starting at the base of transistor 50 - signal B = 0
When supplied, this transistor is cut off. Therefore, a jump from 0 to 1 appears on the control input side 28, and the capacitor 51 becomes almost short-circuited. As a result, transistor 54 is completely controlled to conduct. When the current in the capacitor 51, drawn off with a time constant substantially determined by the resistor 52, falls below the lower limit value, the transistor 54 is switched off again. Since the voltage between the base of transistor 48 and ground (0) is low when transistor 54 is conductive, transistor 48 remains conductive independent of the output voltage of converter 11. Therefore, the connection point between converter 11 and NOT-element 30 at the base of transistor 48 is AND
- has the effect of element 31; The diode 43 is
For a jump from 1 to 0 on the input side 28, there is an approximately short-circuit condition.

The embodiment of FIG. 9 corresponds to the embodiment of FIG. Timing element 29' is connected to the collector of transistor 47 and is furthermore of reverse polarity than in the embodiment of FIG. The emitter and collector of the transistor 54 are connected to the base of the transistor 48.
It is connected to Emitsuta. Since the polarity of the timing element 29' is reversed, this timing element changes from 0 to 1.
It is triggered by a jump change from 1 to 0 rather than by a jump change to . In this case, the timing element emits a 0-signal during the operating time. On the other hand, the conduction of transistor 54 is controlled not by the 1- signal but by the 0- signal. As a result, the output signal of converter 11 is controlled when start-signal B=0. This corresponds to the OR-action of the coupling element 31'.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the control device of the present invention, FIGS. The figure shows a modified embodiment of a part of the control device shown in FIG. 1, FIG. 8 shows a more detailed circuit diagram of a part of the control device shown in FIG. 1, and FIG. 9 shows a part of the control device shown in FIG. 7. A more detailed circuit configuration diagram is shown. 1...Rotor, 4, 5...Electronic switch element,
6... Conversion device, 7... Detector, 8... Pulse shaper, 10... Oscillator, 11... Converter, 13...
... Gate circuit, 14 ... Control circuit, 22 ... Pulse repetition frequency measuring element, 24 ... Reference voltage source, 2
5... Pulse generator, 29, 29'... Timing element.

Claims (1)

[Claims] 1. A control device for a self-starting electric motor having a permanent magnet rotor, a stator with two windings, and electronic switch elements 4, 5 connected in series with the windings to the operating DC voltage, Control circuit 1
4, and output signals S ₁ and S ₂ of a detection device 6 for detecting the rotational angular position of the rotor in a stationary state are supplied to the transmission input side 32 of the control circuit,
Furthermore, a measuring element 22 is provided to identify rotation or non-rotation of the rotor, and when the rotor is rotating, the control input side 28 of the control circuit 14 is controlled by the output signal from the measuring element 22, and the control input side 28 of the control circuit 14 is controlled. The output signal passes through the control circuit 14 to the gate circuit 1.
3 to the transmission input 12, in which case the gate circuit supplies switch control signals Sa ₁ , Sa ₂ of mutually opposite polarity to the electronic switch elements 4, 5 on the basis of the supplied signals. : _a1 , _a2
On the other hand, when the rotor is not rotating, another output signal from the measuring element 22 controls the control input side 28 of the control circuit 14 so that the output signal from the detection device 6 passes through the control circuit. In this case, a starting signal from the pulse generator 25 is applied to the control input 15 of the gate circuit 13 and to the input 28 of the control circuit 14 to open the gate 13 and to open the time circuit. 29, the control circuit 14 is actuated for a predetermined period of time defined by the gate circuit 14, which gate circuit issues switch control signals of mutually opposite polarity to the electric switch elements 4, 5 on the basis of the supplied starting signal.
Sa ₁ , Sa ₂ ; a ₁ , a ₂ are formed, and after the predetermined time has elapsed, the timer circuit controls the control circuit 14 to
The pulse from the detection device 6 is input to the input side 1 of the gate 13.
1. A control circuit for a self-starting electric motor, characterized in that the control circuit is configured to allow the motor to pass through the motor.