JPS6111560B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention applies to rotating electric machines that are used in combination with a rectifier circuit connected to an armature, such as a thyristor motor or an inverter motor that receives power from a power source through a thyristor conversion device, or an alternator that uses a rectifier circuit as a load. Regarding the armature winding of
The purpose is to eliminate or greatly reduce the pulsating torque generated based on the rectangular wave current containing harmonic components flowing through the armature winding. A thyristor motor is shown in FIG. 1 as an example of the above-mentioned rotating electric machine. In the figure, 1 is a motor as a synchronous machine, 2 is a power supply circuit, and the armature winding 3 of the motor 1 is connected to the power supply circuit 2 via a thyristor conversion device 4 consisting of a well-known converter/inverter.
connected to receive more power. In such a rotating electric machine, the armature current waveform becomes a discontinuous rectangular waveform due to the rectifying element in the thyristor conversion device 4 and the smoothing reactor of the DC circuit. As is well known, such a discontinuous rectangular wave contains many harmonic components with different frequencies in addition to the fundamental wave, and as is clear from Fourier series analysis, the particularly large component among these components is
These are the 5th, 7th, 11th, and 13th harmonic components. That is, in addition to the fundamental wave current of the frequency, the above-mentioned harmonic current flows through the armature winding. Among the rotating magnetic fields generated by the current of each component, the rotating magnetic fields φ5 and φ11 of frequencies 5 and 11 due to the 5th and 11th order components rotate in the opposite direction to the rotating magnetic field φ1 due to the fundamental wave. On the other hand, rotating magnetic fields φ7 and φ13 of frequencies 7 and 13 due to the 7th and 13th order components rotate in the same direction as the fundamental wave. Therefore, the relative speeds of the fifth and seventh rotating magnetic fields with respect to the rotating magnetic field of the field poles interlinking with the armature winding are both 6 and 11th.
The relative speeds of the next and 13th order rotating magnetic fields are both 12, and as a result, pulsating torques of frequencies 6 and 12 are generated in the rotating electric machine. Furthermore, the same applies to pulsating torque due to higher-order harmonic components. Such pulsating torque only causes vibration of the shaft and cannot be used as an effective torque. Therefore, when resonance occurs, there is a risk of damage to the structural parts, so it is necessary to prevent the occurrence of pulsating torque as much as possible. is desired. In view of this, the present invention eliminates or reduces the high-frequency rotating magnetic field that causes the generation of pulsating torque, thereby preventing or greatly reducing the generation of pulsating torque, especially pulsating torque at frequencies 6 and 12, which account for large components. In order to achieve this objective, according to the present invention, the armature winding is composed of divided windings consisting of three sets of first, second, and third sets, Spatially, the second and third divided windings are arranged at positions shifted by a phase difference of 20° and 40°, respectively, with respect to the first divided winding, and temporally, the first
By setting a phase difference of approximately 20° and 40° between the divided winding and the second and third divided windings, respectively, and energizing the divided winding, a high-order high-frequency wave is passed through each divided winding. The gist is that the rotating magnetic field generated by the current is offset vectorially. Next, the configuration and operation of the present invention will be explained in detail based on illustrated embodiments. In FIG. 2, the armature winding 3 is a first winding consisting of each phase winding U _A , V _A , W _A .
a second B-divided winding consisting of each phase winding U _B , V _B , W _B , and each phase winding U _C , V _C , W _C
and a third C-divided winding. Although each divided winding is star-connected in the illustrated example, it may be delta-connected. The first, second, and third divided windings of A, B, and C are wound at positions where the B divided winding is spatially advanced by α _AB = 20 degrees in electrical angle with respect to the A divided winding. Further, a C-divided winding is wound at a position advanced by an electrical angle α _AC =40°. Furthermore, each divided winding is connected to the power supply 2 via a separate thyristor converter 4, and by controlling the angle and phase of each thyristor converter 4, the fundamental wave voltage is set as a reference for the first A divided winding. It is determined that voltages whose phases are delayed by α _AB =20° and θ _AC =40° in time are applied to the second and third B and C divided windings, respectively. The turns ratio of each divided winding in the diagram is W _A : W _B : W _C
=1:1:1. According to the above configuration, the first, second, and third A, which are spatially set to have phase differences of 20° and 40° in electrical angle,
For B and C divided windings, time is 20 on the basis of the fundamental wave.
The current of each harmonic component whose phase is shifted by 40° flows. As a result, the frequencies 5 and 7 due to the 5th and 7th harmonic currents to the divided windings A, B, and C.
The rotating magnetic field of φ5A, φ5B, φ5C, and φ7A, φ
The vector diagrams of 7B and φ7C are shown in Figure 3 a and b. That is, for a rotating magnetic field φ5A, φ5B has a temporal phase difference of 20° x 5 in addition to a spatial phase difference α _AB = 20°.
= 100° delay, resulting in a total phase difference of 120°. Further, φ5C is the sum of the spatial phase difference α _AC =40° and the temporal phase difference 40°×5=200°, resulting in a phase difference of 240°. Furthermore, since the sizes of φ5A, φ5B, and φ5C are equal, as a result, as is clear from the figure, the vector sum of φ5A, φ5B, and φ5C is φ〓5A+φ〓
5B+φ〓5C=0, and the fifth-order rotating magnetic field disappears. Similarly, the rotating magnetic fields φ7A, φ7B, and φ7C are the third
As shown in Figure b, each has a phase difference of 120°, and the vector sum is 0. Note that the rotating magnetic field of the seventh-order component has a rotation direction opposite to that of the fifth-order component, and a temporal phase difference is applied in the opposite direction to the spatial delay phase angles of 20° and 40°. If we organize the above results and express them in the formula, we get the following.

【table】

【table】

【table】

[Table] The above operation is valid when the frequency of the rotating magnetic field is 6g±1 (except when g is a multiple of 3), and as a result, the frequency is 6, 12, 24, 30
, etc. 6(3n+1), and 6
(3n+2) (however, n=0, 1, 2,……
), the generation of pulsating torque is prevented. In addition, as the high-frequency rotating magnetic field is eliminated as described above, the copper loss and iron loss occurring in the rotating electric machine are also reduced, making it possible to improve efficiency. In the embodiment shown in FIG. 2, separate thyristor converters 4 are required in order to set temporal phase differences of 20° and 40° between the A, B, and C divided windings. If each terminal of the armature winding 3 is led out through a slip ring, nine slip rings are required. In order to improve this point, the first, second, and third divided windings are connected and configured as in the embodiment shown in Fig. 4, so that only three external lead-out terminals U, V, and W are required. It is easy to use, and only requires one thyristor conversion device. In other words, in the embodiment shown in FIG. 4, the first divided winding includes each phase winding U _A , V _A , W
It is a star-connected A-divided winding consisting of _A , and for this A-divided winding, the second and third B, C
As shown in the figure, each of the divided windings is connected between the center point of each phase winding U _A , V _A , W _A in the A divided winding and the adjacent external lead-out terminals U, V, W of different phases. Each phase winding U _B , V _B , W _B , and U
It consists of _C , _Vc , and _Wc . Note that the A, B, and C divided windings have spatial phase differences in electrical angle of α _AB = 20° and α _AC = It is set at 40°. According to the wiring connection of this embodiment, the temporal phase difference between the A-divided winding and the B and C-divided windings is θ _AB =19.1° and θ _AC =40.9°, with the fundamental wave as a reference.
A phase difference of approximately 20° and close to 40° is set. In the embodiment shown in FIG. 4, the turns ratio of each of the divided windings A, B, and C is set to W _A :W _B :W _C =1:1.35:1.35 or a value close to it. As an example, the practical turns ratio W _A , W _B , W _C =3 for the connection shown in FIG. 4:
According to the trial calculation of the degree of reduction of each harmonic rotating magnetic field for the 4:4 example, compared to the conventional armature winding, φ5 = 4.8%, φ7 = 6.7%, φ11 = 9.2
%, φ13=10.7%. As described above, according to the present invention, the rotating magnetic field of harmonic components that cause pulsating torque is skillfully canceled out by the divided windings, and is eliminated or greatly reduced. ,
The excellent effect of suppressing the generation of pulsating torque of 6(3n+1) and 6(3n+2) such as 12 can be achieved.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram of a thyristor motor shown as an example of a rotating electric machine to which the present invention is applied, Fig. 2 is a wiring diagram of an embodiment of the present invention, and Fig. 3 a and b are explanations of operation according to an embodiment of the present invention. FIG. 4 is a wiring diagram showing another embodiment of the present invention. 1: Rotating electric machine, 2: Power supply circuit, 3: Armature winding, 4: Thyristor conversion device as a rectifier circuit, U _A , V _A , W _A : First divided winding, U _B , V _B ,
W _B : Second divided winding, U _C , V _C , W _C : Third divided winding, α _AB , α _AC : Spatial phase difference, θ _AB , θ _AC :
Temporal phase difference.

Claims (1)

[Claims] 1. In a rotating electric machine that is used in combination with a rectifier circuit connected to an armature winding, the armature winding has a first
Consisting of three sets of divided windings, the second and third, the second and third divided windings have a spatial phase difference of 20° and 40° in electrical angle, respectively, with respect to the first divided winding. In addition, the second and third divided windings are placed at different positions, and the second and third divided windings are placed at different positions relative to the first divided winding with respect to the fundamental wave.
An armature winding for a rotating electrical machine characterized by having a phase difference of approximately 20° and 40° between the divided windings so as to conduct electricity. 2. In the armature winding described in claim 1, three sets of divided windings arranged with spatial phase differences of 20° and 40° in electrical angle are arranged in a star configuration. The first divided winding of 1. An armature winding for a rotating electrical machine, comprising a second and third divided winding connected across an external lead-out terminal.