JP2522675B2 - Current phase compensation method for two-phase linear electromagnetic device - Google Patents

Description

The present invention relates to a two-phase linear electromagnetic device such as a two-phase linear motor, a two-phase linear electromagnetic pump, or a two-phase electromagnetic stirrer. It concerns a compensation method.

[Conventional technology]

FIG. 6 is a layout drawing showing the relationship between the iron core and the coil of a 2-pole 2-phase flat linear electromagnetic device, and FIG. 7 is an upper half longitudinal sectional view of a 2-pole 2-phase cylindrical linear electromagnetic device. The figure is an operation connection diagram of these electromagnetic devices.

Whether the two-phase linear electromagnetic device 1 is flat or cylindrical, the U-phase coil 21 and the V-phase coil 22 are geometrically arranged at the magnetic pole pitch τ in the iron core 3 having a finite length in the traveling direction of the magnetic field. 1 / _p
As shown in FIG. 8, the U-phase coil 21 and the V-phase coil 22 are energized by the two-phase AC power source 4 having a phase difference of 90 ° in the output voltage. It

In FIG. 6, the U-phase coil 21 and the V-phase coil 22 are offset from each other by 1/2 with respect to the magnetic pole pitch τ _p , and the flat core 3
It is stored in the slot provided in the. Reference characters a1, a2 and a3, a4 denote terminals of the U-phase coil 21 and the V-phase coil 22, respectively.

In FIG. 7, the U-phase coil 21 and the V-phase coil 22 are each formed in an annular shape, and the iron core 3 formed by arranging the cylindrical shape or the iron core blocks in a radial direction is 1 / distance relative to the magnetic pole pitch τ _p . It is stored in a slot that is offset by 2. The terminal code of each coil is the same as in FIG.

The two-phase AC power supply 4 shown in FIG. 8 uses a Scott connection transformer, and the primary side is a three-phase AC power supply R, S,
It is connected to the T-phase and outputs the U-phase and V-phase voltages with 90 ° different phases from the secondary side. One end of the first primary winding 61 is connected to the R phase, and the other end is connected to an intermediate point of the second primary winding 62 whose both ends are connected to the S phase and the T phase.

The first secondary winding 51 coupled to the first primary winding 61 outputs a U-phase voltage, the terminal codes of which are b1 and b2.
The second secondary winding 52 coupled to the secondary winding 62 outputs the V-phase voltage, the terminal codes of which are b3 and b4, and the U-phase voltage and the V-phase voltage have a phase difference of 90 °. Will be things.

The U-phase output terminals b1 and b2 of the 2-phase AC voltage 4 are connected to the U-phase coil terminals a1 and a2 of the 2-phase linear electromagnetic device, and the V-phase output terminals b3 and b3,
b4 is connected to V-phase coil terminals a3 and a4, respectively.
With such a configuration, a traveling magnetic field is generated in the arrow direction shown in FIGS. 6 and 7.

[Problems to be solved by the invention]

FIG. 5 is an equivalent circuit diagram of an electric circuit of the two-phase linear electromagnetic device. The U-phase coil and the V-phase coil have winding resistance R and self-reactance L, respectively, and are energized by voltages v _u and v _v having a phase difference of 90 °.

Mutual inductance M between U-phase coil and V-phase coil
Are coupled together, the energizing voltage v _u , v _v of both phases and the current i _u , of both phases are
The following relationships (1) and (2) are established between i _v .

v _u = i _u (R + jωL) + i _v (jωM) (1) v _v = i _u (jωM) + i _v (R + jωL) (2) where ω is the angular frequency of the two-phase AC power supply.

The mutual inductance M between the U-phase coil and the V-phase coil, which are arranged with a phase angle difference of 90 °, has a mutual linkage between the two phases when there is no finite end in the magnetic flux traveling direction as in a rotating electric machine. The intersecting magnetic flux becomes almost zero.

FIG. 3 is a vector diagram when the mutual inductance is zero, and the U-phase and the V-phase to which the orthogonal biasing voltages v _u and v _v are applied have the resistance R and the self-inductance L independently. The currents i _u and i _v flow in the circuit, and the currents i _u and i _v have a phase difference of 90 ° like the voltage.

However, when the magnetic flux has a finite end in the traveling direction of the magnetic flux like a two-phase linear electromagnetic device, the linkage of the magnetic flux between the U-phase coil and the V-phase coil is not zero due to its geometrical finiteness, and The inductance M cannot be ignored.

FIG. 4 is a vector diagram when the mutual inductance is not zero, and the voltage drops i _v (jωM) and i _u (jω) due to the mutual inductance M in the U-phase and V-phase circuits, respectively.
M) occurs, which causes the phase difference between the U-phase current i _u and the V-phase current i _v to be larger than 90 ° (90 ° + φ), and the current value is also unbalanced.

In this case, the magnetic flux distribution B (x) whose origin is the magnetic pole center of the U-phase coil is when the maximum magnetic flux is Bm. here Therefore, the maximum value of the magnetic flux varies depending on the position depending on the phase shift angle φ.

That is, for example, when the magnetic pole axis x = 0 of the U phase, the maximum value of the magnetic flux does not change depending on the phase shift angle φ, but at the intermediate point πx / τ _p = π / 4 between the U phase and the V phase. Therefore, at φ = 10 °, the maximum value of the magnetic flux at that point is 0.91.
Doubled.

In this way, in the two-phase linear electromagnetic device, if the two-phase power source is directly connected as in the conventional case, the current phase is deviated from 90 ° due to the mutual inductance between the two-phase coils, and the current value becomes unbalanced and The uniformity of the generated magnetic field will be lost, and the electromagnetic characteristics will be deteriorated.

The present invention relates to a current phase compensating method for solving these conventional drawbacks and obtaining a desired electromagnetic characteristic.

[Means for solving problems]

A current phase compensating method for a two-phase linear electromagnetic device according to the present invention includes two-phase coils geometrically arranged and wound with a phase difference of 1/2 magnetic pole pitch between two phases of an output voltage. In a two-phase linear electromagnetic device energized by a two-phase alternating current power supply having a phase difference of 90 °, the output voltage of the two-phase alternating current power supply of a different phase is set to a predetermined phase for each two-phase circuit of the two-phase linear electromagnetic device. The secondary side of a phase compensating transformer for converting into a compensating voltage is inserted, and the secondary output voltage of the transformer is connected to each phase voltage so as to be added in the same phase as the primary input voltage.

By providing a tap on the secondary side of the phase compensating transformer, when the mutual reactance of the two-phase linear electromagnetic device is uncertain at the design stage, the tap is appropriately selected according to the current phase shift. May be.

[Action]

FIG. 2 is a vector diagram in the case of the current phase compensation method for a two-phase linear electromagnetic device according to the present invention. As the energizing voltage v _u of the U-phase coil of the two-phase linear electromagnetic device, the U-phase output voltage v _su of the two-phase AC power supply and the compensation voltage v _tv obtained by converting the V-phase output voltage with the phase compensation transformer are output as the V-phase output. _Assuming that the voltage is added in the same phase as the voltage v _sv , the bias voltage v _v of the V-phase coil of the two-phase linear electromagnetic device is used as the V-phase output voltage v _sv of the two-phase AC power supply.
And U-phase output voltage converted by a phase compensation transformer
By adding v _tu in the same phase as the U-phase output voltage v _su , the voltage drops i _v (jωM) and i _u (jωM) caused by the mutual inductance M between the two-phase coils of the two-phase linear electromagnetic device. compensating the phase shift due to both phase currents i _u, i
The phase difference between _v can be kept at 90 °.

〔Example〕

FIG. 1 is a connection diagram of an embodiment of a current phase compensating method for a two-phase linear electromagnetic device according to the present invention, and the same reference numerals as those in FIG. 8 denote the same or the same function. In FIG. 1, 71 and 72 are phase compensation transformers, each of which is 1
It has secondary windings 91 and 92 and secondary windings 81 and 82.

Primary windings 91 and 92 of phase compensating transformers 71 and 72
Are connected to the V-phase output terminals b3 and b4 and the U-phase output terminals b1 and b2 of the two-phase AC power source 4, respectively, and are connected to the phase compensation transformer 71.
Secondary windings 81 and 82 of Nos. 72 and 72 are connected so as to add the phases to the outputs of the two-phase alternating-current power supplies having phases different from the primary winding, that is, U-phase and V-phase.

Here, the secondary voltages v _tv and v _tu of the phase compensating transformers 71 and 72 are | v _tv | ≈ | from the phase shift angle φ generated by the mutual inductance M and the respective primary voltages v _sv and v _su. Select by v _sv | tan (φ / 2) | v _tu | ≈ | v _su | tan (φ / 2).

When the effect of the mutual inductance M of the two-phase linear electromagnetic device 1 is uncertain at the design stage, voltage adjustment taps are provided in advance on the secondary windings 81 and 82 of the phase compensation transformers 71 and 72, and There is also a method of using an appropriate voltage tap according to the phase shift.

It is also possible to use an induction voltage regulator instead of the phase compensating transformers 71 and 72 to continuously select the phase compensating voltage.

〔The invention's effect〕

According to the current phase compensation method for a two-phase linear electromagnetic device according to the present invention, it is possible to reduce the non-uniformity of the magnetic field due to the finite end that occurs in the conventional two-phase linear electromagnetic device and the deterioration of the electromagnetic characteristics due to the non-uniformity. In addition to obtaining a spatially uniform magnetic field distribution, electromagnetic characteristics such as thrust, electromagnetic force and stirring force are significantly improved.

Further, since the imbalance of the current between the two phases can be eliminated, the thermal resistance can be improved and the size and weight can be reduced.

[Brief description of drawings]

FIG. 1 is a connection diagram of an embodiment of a current phase compensation method for a two-phase linear electromagnetic device according to the present invention, FIG. 2 is a vector diagram at that time, and FIG. 3 is a vector when mutual inductance is zero. 4 and 5 are vector diagrams when mutual inductance is not zero, FIG. 5 is an equivalent circuit diagram of an electric circuit of a two-phase linear electromagnetic device, and FIG. 6 is a two-pole two-phase flat linear electromagnetic device. Arrangement diagram showing the relationship between the iron core and the coil, No. 7
The drawing is a vertical cross-sectional view of the upper half of a two-pole two-phase cylindrical linear electromagnetic device, and FIG. 8 is a conventional operation connection diagram of these electromagnetic devices. 1 …… 2-phase linear electromagnetic device, 21 …… V-phase coil, 22 ……
U-phase coil, 3 ... Iron core, 4 ... 2-phase AC power supply, 51, 52,
81,82 …… Secondary winding, 61,62,91,92 …… Primary winding, 71,72
...... Phase compensation transformer.

Claims (2)

(57) [Claims] 1. A two-phase AC power supply having a two-phase coil geometrically arranged and wound with a phase difference of 1/2 magnetic pole pitch and having a phase difference of 90 ° between two phases of an output voltage. In a two-phase linear electromagnetic device to be energized, a phase compensating transformer for converting the output voltage of the two-phase AC power supply of a different phase in each two-phase circuit of the two-phase linear electromagnetic device into a predetermined phase compensation voltage. A current phase compensation method for a two-phase linear electromagnetic device in which a secondary side is inserted and connected so that the secondary output voltage of the transformer is added in phase with the primary input voltage for each phase voltage. 2. A current phase compensating method for a two-phase linear electromagnetic device according to claim 1, wherein a tap for voltage adjustment is provided on the secondary side of the phase compensating transformer.