JPH0262044B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] The present invention relates to magnetic amplifiers, and more particularly to improvements in small and lightweight magnetic amplifiers.

〔Technical field〕

Conventionally, saturable reactor type magnetic amplifiers have been proposed, but conventional magnetic amplifiers use materials such as iron and copper that increase in proportion to the increase in rated capacity, resulting in significantly large dimensions and weight. It was extremely expensive. Moreover, the large waveform distortion of the output voltage required a bulky and expensive external filter.

[Purpose of the invention]

An object of the present invention is to provide a small and lightweight magnetic amplifier with a good output waveform.

Another object of the present invention is to provide a highly efficient magnetic amplifier that has a large load capacity with a small self-capacity, uses less material, and significantly reduces iron loss and copper loss.

[Structure of the invention]

The magnetic amplifier of the present invention includes a first series winding and a first series winding.
a main flux comprising a first saturable iron core having a shunt winding connected in series with the series winding and a second series winding connected in series with the shunt winding with a polarity different from the shunt winding; at least one magnetic shunt core comprising a loop path and an air gap disposed between the shunt winding and the second series winding to bypass a portion of the main flux loop path; a second magnetically coupled portion of the first saturable core and an extension thereof between the magnetic shunt core and the second series winding;
an auxiliary magnetic velocity loop path having a saturable iron core;
a control winding for magnetically saturating the part of the first saturable core via the saturable core to shift the magnetic flux of the first series winding and the shunt winding to the magnetic shunt core; It is characterized by having the following.

〔Example〕

A preferred embodiment of the magnetic amplifier according to the present invention will be described with reference to FIGS. 1-5.

In FIG. 1, a magnetic amplifier 10 includes a first core portion 12a and a second core portion 1 that constitute a main magnetic flux loop path.
2b and a magnetic shunt core 14 for bypassing a portion of the main magnetic flux loop path, the first volume core 12 acts as a first saturable core. A first series winding 16 and a shunt winding 18 are wound on the first core part 12a of the first core 12, and a second series winding 20 is wound on the second core part 12b. .
The first series winding 16 is connected between the high voltage terminal U and the medium voltage terminal U, and the shunt winding 18 is connected to the first series winding 16.
connected in series with the same polarity. The lower end of the shunt winding 18 is connected to the first neutral point V ₁ . The second series winding 20 connects the lower end of the shunt winding 18 with the second neutral point V ₂
The first series winding 16 is connected with the opposite polarity between the first series winding 16 and the first series winding 16 . A second winding core 22 that acts as a second saturable core to control the magnetic flux density of the magnetic shunt core 14 by changing the magnetic saturation state of at least a portion of the second core portion 12b, and a control winding 24. is provided.

2 and 3, the first volume core 12 includes a center leg 26 and outer legs 28, 30 that constitute a main magnetic flux loop path. The center leg 26 includes a first core portion 12a and a second core portion 12b separated by the magnetic shunt core 14. Additionally, the center leg 26 includes an extension, or third core portion 12c, extending outwardly from the outer legs 28,30. center leg 26
is placed on the first core 12, and the fixture 3
2 and 34 to be fixed to each other and integrated. As is clear from FIGS. 2, 3, and 5, the magnetic shunt core 14 is composed of a C-shaped cross-sectional core made by laminating a large number of silicon steel plates. Groove 14a of magnetic shunt core 14 is arranged to magnetically couple with center leg 26. end portion 14b of magnetic shunt core 14;
14c is arranged between the coil blocks of the first series winding 16 and the shunt winding 18 and the coil block of the second series winding 20, with inserts 36 and 38 having a required thickness corresponding to a constant air gap sandwiched therebetween. Volume 1 iron core 1
placed on the outer legs 28, 30 of 2;
The outer leg 2 is fixed by the fixing devices 40 and 42.
8 and 30, each core is integrated.
The magnetic shunt core 14 transfers a part of the magnetic flux of the main magnetic flux loop path to a gap (intermediate 36,
38) to the outer legs 28, 30 to regulate the output voltage as described below and to attenuate harmonics and reduce waveform distortion of the output voltage. The second winding core 22 has a center leg on the underside of the magnetic shunt core 14, that is, between the coil blocks of the first series winding 16 and shunt winding 18 and the coil block of the second series winding 20. The iron cores are arranged on the upper part of the second core part 12b and the lower end part of the third core part 12c of 26, and the respective iron cores are integrated and magnetically coupled by the fixtures 44 and 46. in this way,
The second volume core 22 is arranged so as to overlap the lower half of the first volume core 12, and magnetically saturates a part of the first saturable core so that the magnetic flux of the second series winding 20 is transferred to the first series winding. 16 and shunt winding 18, and causes the magnetic flux of first series winding 16 and shunt winding 18 to be shifted to magnetic shunt core 14. The first series winding 16 and the shunt winding 18, the second series winding 20 and the control winding 24 are connected to the first to fourth windings of the center leg 26, respectively.
It is wound on the third core parts 12a, 12b, and 12c and arranged in substantially the same plane. Furthermore, the upper surface and the lower surface of each winding are arranged so as to be aligned with the upper surface of the second-volume core 22 and the lower surface of the first-volume core 12, respectively. That is, the coil block consisting of the first series winding 16, the shunt winding 18, the second series winding 20, and the control winding 24 are connected to the center leg 26, the first It is arranged approximately within the thickness of the two-turn iron cores 12 and 22.
The third core portion 12C of the center leg 26 is
Extending outside the wound core 12, the control winding 24 is wound onto the lower end 12c of the center leg 26. A second core 22 surrounds the coil block of the second series winding 20 and the control winding 24. In FIGS. 2 and 3, the upper and lower parts of the second core 22 constitute an auxiliary magnetic flux loop path with the center leg 26 by fixtures 44 and 46, respectively, and when a high current control current is supplied to the control winding 24, It functions as a path for the magnetic flux of the control winding 24. That is, the magnetic flux of the control winding 24 partially magnetically saturates the second core portion 12b of the center leg 26, causing the magnetic flux of the first series winding 16 and the shunt winding 18 to be magnetically separated from the main magnetic flux loop. It is shifted to the outer legs 28, 30 via the road core 14.

The first series winding 16 and the shunt winding 18 are connected to the center
The second series winding 20 is wound on the first core part 12a of the leg 26 to constitute an autotransformer.
2b, the first series winding 16 has a polarity opposite to that of the first series winding 16, and is so-called differentially coupled.

In the above configuration, the intermediate voltage terminal u and the first neutral terminal
When V ₁ is connected to an alternating current and high voltage terminal U and second neutral terminal V ₂ are connected to a load, the first and second
A large current flows through the series windings 16 and 20, and the shunt winding 1
8, an input current, an output current, and a difference current flow.

In order to reduce the self-capacitance of the magnetic amplifier 10 and thereby downsize the device, the winding ratio between the first series winding 16 and the shunt winding 18 is selected to be large. for example,
Connect a 100 [V] AC power supply to the medium voltage terminal U and the first neutral terminal V ₁ , and connect the high voltage terminal U and the second neutral terminal V ₂
When designing the magnetic amplifier 10 for the purpose of connecting the
Winding n ₁ of the first series winding 16 and winding n ₂ of the shunt winding 18 are selected to increase to 101V. Next, the winding _n3 of the second series winding 20 is determined according to the variation range of the output voltage to be adjusted. That is, when changing the output voltage within a range of 10% from 101 to 90.9 [V], the winding _n3 of the second series winding 20 is determined by the following formula.

n ₃ = (n ₁ + n ₂ ) × E ₀ −E′ ₀ /E ₀ In the above formula, E ₀ is the maximum output voltage 101 [V]
E′ ₀ corresponds to the minimum output voltage of 90.9 [V].

1 and 2, when no DC control current is supplied to the control winding 24, the first series winding 16, the shunt winding 18, and the second series winding differentially coupled to the shunt winding 18 The magnetic flux generated by 20 is transferred from the center leg 26 to the outer legs 28, 30.
and circulates to the center leg 26.
At this time, the magnetic flux φ 1 generated by the first series winding 16 and the shunt winding 18 and the magnetic flux φ ₂ generated by the second series winding ₂₀
Since they are in opposite directions, the mutual magnetic flux as a whole acts as a difference. Therefore, the output voltage at this time is the minimum E′ ₀ .

Next, connect the control winding 24 to a DC power source (not shown).
to the center via the second volume iron core 22.
When the second and third core portions 12b and 12c of the leg 26 are magnetically saturated, the magnetic flux φ ₁ generated by the first series winding 16 and the shunt winding 18 is shifted to the magnetic shunt core 14. At this time, the magnetic flux φ ₁ is
a, circulates through the outer legs 28, 30 and the magnetic shunt core 14, and the output voltage between the terminals U, _V2 is at a maximum _E0 . When the DC current supplied to the control winding 24 is reduced, the output voltage is reduced accordingly. In this way, by movably controlling the magnetic saturation states of the second and third core portions 12b and 12c of the center leg 26, the difference between the second series winding 16 and the shunt winding 18 can be adjusted. The magnetic flux of the first series winding 16 and the shunt winding 18 shifted to the magnetic shunt core 14 is controlled by changing the dynamic coupling state, and the output voltage between the terminals U and V ₂ can be variably controlled.

〔Effect of the invention〕

As is clear from the above, the magnetic amplifier according to the present invention provides the following effects.

Since the magnetic amplifier of the present invention employs a structure with extremely small self-capacitance, it can be significantly reduced in size, weight, and cost. Furthermore, the magnetic amplifier uses significantly less material, and iron loss and copper loss are reduced, resulting in high efficiency. That is, the overall length of the iron core is shortened, reducing magnetic reluctance, reducing overall material requirements, and significantly reducing sources of loss, resulting in high efficiency. Further, in the structure of the present invention, it is possible to employ a single control winding and each winding core and each winding are arranged in the same plane, so that the magnetic amplifier can be made ultra-thin and compact. In addition, the center
Since the leg and each core are integrated with a fixture, manufacturing and assembly are easy. Furthermore, since a magnetic shunt is provided in the main magnetic flux loop path via an air gap, harmonics are attenuated and waveform distortion of the output voltage is improved.

[Brief explanation of drawings]

FIG. 1 is a wiring diagram of a preferred embodiment of the magnetic amplifier according to the present invention, FIG. 2 is a plan view of the magnetic amplifier of FIG. 1, FIG. 3 is a right side view of the magnetic amplifier of FIG. 2, and FIG. FIG. 2 shows a bottom view of the magnetic amplifier, and FIG. 5 shows a sectional view taken along line V-V in FIG. 2, respectively. 12...First volume iron core, 16...First series winding,
18...Shunt winding, 20...Second series winding, 22
... Second volume iron core, 24 ... Control winding, 26 ... Center leg, 28, 30 ... Outer leg.

Claims (1)

[Claims] 1. A first series winding, a shunt winding connected in series to the first series winding, and a second series winding connected in series to the shunt winding with a polarity different from that of the shunt winding. a main magnetic flux loop path including a first saturable core having a series winding; and a main magnetic flux loop path disposed between the shunt winding and the second series winding to bypass a portion of the main magnetic flux loop path. at least one magnetic shunt core with an air gap for magnetically discharging a portion of the first saturable core and an extension thereof between the magnetic shunt core and the second series winding. an auxiliary magnetic flux loop path having a coupled second saturable core; and an auxiliary magnetic flux loop path wound around the extension of the first saturable core and connected to the first saturable core via the second saturable core. a control winding for magnetically saturating the first series winding and shifting the magnetic flux of the shunt winding to the magnetic shunt core. 2. The first saturable core includes a first-turn core having a center leg and an outer leg, and the auxiliary flux loop path surrounds the second series winding and the control winding on the center leg. 2. The magnetic amplifier according to claim 1, further comprising: a second-volume core disposed in the center leg, and wherein said center leg includes said extension portion extending outward from said first-volume core. 3, further comprising a first fixture for fixing the first volume core and the center leg, and a second fixture for fixing the second volume core and the center leg. A magnetic amplifier according to claim 2. 4. On one side of the center leg, the first
4. The magnetic amplifier according to claim 2, wherein a wound core is disposed, and the second wound core is disposed on the other side of the center leg. 5. The first series winding, the shunt winding, the second series winding, and the control winding are arranged in substantially the same plane. magnetic amplifier. 6. The first series winding and shunt winding, the second series winding, and the control winding are connected to the center winding.
6. The magnetic amplifier according to claim 5, wherein the magnetic amplifier is disposed substantially within the thickness of the leg and the first and second cores.