JPS61295616A - Electromagnetic device - Google Patents

Abstract

PURPOSE:To reduce the magnetostrictions of the amorphous magnetic thin bands into 0 or the vicinity of 0 and to maintain the symmetrical property of the hysteresis curve generating in each amorphous magnetic thin band by a method wherein a capacitor is provided bteween the intermediate lead-out conductor of the primary winding of an oscillating transformer and the grounding conductor thereof. CONSTITUTION:A capacitor C is provided between the intermediate lead-out conductor of the primary winding of an oscillating transformer ST, which is constituted of saturable cores consisting of amorphous magnetic thin bands, and the grounding conductor thereof. However, when a DC electric power E is being impressed on the circuits and the electric power E is turned OFF, the oscillation operation is made to gradually extinguish by the charge being stored in the capacitor C and the residual magnetic flux is dwindled into 0 or the vicinity of 0. As the residual magnetic flux Br is left to stand in 0 by the circuits, the symmetrical property of the hysteresis waveform is held and the effect of preventing an abnormal waveform from generating can be obtained. The symmetrical property of the hysteresis waveform is maintained in such a way, and at the same time, the waveform is a high-angle type and can be obtained in low loss because of the amorphous magnetic thin bands, and furthermore, the waveform distortion is eliminated, and moreover, the highly reliable saturable cores can be realized.

Description

Detailed Description of the Invention [Technical Field] The present invention relates to an electromagnetic device using an amorphous magnetic ribbon.

[Background Art J Since square characteristics are generally required for saturable core materials used in saturable reactors, magnetic amplifiers, etc.
For high frequencies, permalloy or the like is used, and ferrite is not suitable. Amorphous magnetic ribbons have excellent square properties and lower high frequency loss than permalloy, making them ideal for saturable cores.

The composition of an amorphous magnetic ribbon is generally the same as metal elements (
Fe, Co, Ni) and metalloid elements (Si.

P, C, 8%), for example, Fetas i+oB 12, Cos i C
There are r 26 C+ s, etc. The manufacturing method for amorphous magnetic ribbon is a unique manufacturing method called the high-speed quenching method, in which an alloy having the above composition is melted and rapidly cooled to freeze its structure into an amorphous state with no crystals.

The shape (thickness, width, surface condition) of the amorphous magnetic ribbon depends on the rapid cooling conditions, but the thickness ranges from 5 μl to 10 μl.
It is as thin as 0μ, which is one of the reasons for reducing eddy current loss and improving high frequency characteristics. Further, after quenching, annealing is usually performed to significantly improve the properties as a saturable core. Annealing requires setting of conditions such as annealing time, temperature, temperature increase rate, temperature decrease rate, magnetic field, etc., and various conditions are set depending on the composition of the amorphous magnetic ribbon, the purpose of the core used, etc. If the composition has a magnetostriction of O or near O, an optimum saturable core with extremely good squareness can be realized by appropriately annealing.

The composition of magnetostriction 0 is Fe4. sCo, o, sS i+sB
+osF elco72P +8s aA O,3,
Using Cot6MnsB 9.5s i+4.5 as an example with CotoMnsB j, 5s iz, s, etc.,
The annealing conditions were to raise the temperature at a temperature increase rate of 20°C/win, and to
The temperature was maintained at ℃ for 20 minutes, and then the magnetic properties were investigated by cooling in water.
As shown in Fig. 5s iz, s), the AC magnetic properties at a frequency of 20 kHz were extremely excellent in squareness with a squareness ratio of 94%, and a core with a coercive force of 250 m0e and low loss could be realized. In addition, in the IJ&3 diagram, the horizontal axis is the magnetizing force H (+mO
e), vertical pongee is assumed to have a magnetic flux density B (KG), 81° in the figure is the saturation magnetic flux density, Br is the residual magnetic flux density, and Ha is the coercive force. Here, in Fig. 3, the saturation magnetic flux density B, #8
．． 4KG, residual magnetic flux density Br#7.9KG, coercive force Hc
#250m.

e1 squareness ratio B r / B lo # is 94%.

Reggiator switching saturable core, like above
When applied to inverters and alpha lamp devices, it has superior electrical properties compared to conventional permalloy. However, when amorphous magnetic ribbons are applied to equipment, problems arise due to deterioration of magnetic properties.

Fig. 4 shows a circuit diagram of a two-stone blocking oscillator using an oscillation transformer ST configured with a saturable core using an amorphous magnetic ribbon of the aforementioned Co7oMngBsa5siz+s composition. be. This blocking oscillator uses DC power supply E as a power source, and
one transistor T r,.

The output winding n of the oscillation transformer ST is composed of Tr2, resistors R, , R2, the above-mentioned oscillation transistors, etc. The output voltage is rectified by the diode pre-7 DB't' and further smoothed by the capacitor CI to supply power to the load 1.

When the voltage of DC power supply E is applied, i
3.12, The current flows in the three paths i, and becomes the base current of the transistor TrlyTr2, but the base-emitter voltage and base current characteristics (Vaε-Is) of the transistors Tr and Tr2 are not exactly the same. Furthermore, a difference in magnitude occurs between the collector currents of the transistors Tr and Tr2. Now, assuming that the collector current of transistor Tr1 is large, an oscillation transformer ST consisting of a saturable core
A voltage is induced between the windings ■-■-〇 in the direction of the dotted line shown in the figure. This voltage increases the total input current of the transistor Tr and decreases the base current of the transistor Tr2, so the current ic increases and the current ic2 decreases.

Then, the induced voltage in the direction of the dotted line further increases, transistor Tr is turned on, and transistor Tr2 is turned off.

FIG. 5 shows the AC hysteresis curve of the saturable core, and the state where the transistor T1 is on and the transistor Tr2 is off corresponds to OX open in FIG.
When the X point in the jfJ5 diagram is reached, magnetic saturation occurs, and no voltage is induced in the windings of the oscillation transformer ST.
The current icl decreases, and an induced power is generated between ■ and ■, causing the base current of the transistor Tr2 to flow, turning off the transistor Tr, and turning off the transistor Tr.
2 is turned on. In this state, a loop is traced from point X to point Y in FIG. When the point Y is reached, the transistor Tr2 is turned off and the transistor Trl is turned on according to the same principle as before, and the transition is made from the Y point to the X point, and the oscillation is repeated thereafter.

Although oscillation is performed according to the above-mentioned principle, the characteristics of the saturable core of the oscillation transformer ST are affected when the power is cut off. That is, when the power is turned off at the saturation state in FIG. 5, that is, at point X, the magnetizing force H becomes O, and oscillation stops at the magnetic flux density Br.

Residual magnetic flux exists in the amorphous magnetic ribbon of the saturable core. If left in this state, the shape of the hysteresis loop will change and become asymmetrical, as shown in Figure 6.
I discovered that. FIG. 6(a) shows the waveform when left at the residual magnetic flux density Br, and FIG. 6(b) shows the waveform when left at the origin without residual magnetic flux. In Fig. 6(a), A indicates the initial characteristics, and the opening indicates the characteristics when left at the residual magnetic flux density, and in Fig. 6(b), A indicates the initial characteristics.
Each mouth shows the characteristics when left at the origin. Residual magnetic flux density B ", an increase in coercive force is observed in both cases when the origin is left, but when the origin is left, the waveform is symmetrical, and the residual magnetic flux density B
When r is left alone, it is asymmetrical. The cause of this is not clear, but it is thought that it is because the magnetic domain walls are fixed when the residual magnetic flux density Br is left undisturbed. Asymmetry in the hysteresis waveform has an adverse effect on electrical characteristics such as oscillation frequency and output, so countermeasures against this are important and necessary.

[Object of the Invention] The present invention has been provided in view of the above-mentioned points, and has a method of reducing the magnetostriction of the Amol 77 magnetic ribbon to O or near O by a degaussing means, thereby maintaining the symmetry of the hysteresis curve. The object of the present invention is to provide an electromagnetic device that has the following characteristics.

[Disclosure of the invention 1 Embodiments of the present invention will be described below with reference to the drawings.

As described above, the hysteresis curve becomes asymmetric when there is residual magnetic flux other than the origin. Therefore, symmetry can be achieved by providing a circuit function, that is, a demagnetizing means, so that when the power is turned off, the origin, that is, the residual magnetic flux becomes zero. This degaussing means will be explained using an example. FIG. 1 is a specific circuit diagram of this circuit, which is a two-stone blocking oscillator, and the difference from the circuit shown in FIG. 4 is that a capacitor C is connected in parallel with a DC power source E. That is, a capacitor C is provided between the intermediate lead wire of the primary winding of the oscillation transformer ST, which is composed of a saturable core made of a 7M 7T magnetic ribbon, and the ground wire.

Therefore, when DC 1 [tE is applied to the circuit, it is the same as described above, and when the power supply E is turned off, the oscillation operation is gradually extinguished by the charge accumulated on the capacitor C1,:W, and the remaining The magnetic flux is set to O or near zero.

FIG. 2 shows this state. Since this circuit leaves the residual magnetic flux Br at 0, the symmetry of the hysteresis waveform is maintained, which is effective in preventing abnormal waveforms. In this way, the symmetry of the hysteresis waveform is maintained, and
By using the Amol 77 magnetic ribbon, it is possible to realize a highly reliable saturable core that has a high square shape, low loss, and no waveform distortion. The main idea of the present invention is
By stopping the operation when the residual magnetic flux is 0 or near 0, waveform distortion is prevented, and it goes without saying that there are no limitations in terms of circuitry or configuration.

[Effects of the Invention] As described above, the present invention includes an amorphous magnetic ribbon and a demagnetizing means for setting the magnetostriction of the amorphous magnetic ribbon to 0 magnetostriction or around 0 magnetostriction. By setting the magnetostriction of the amorphous magnetic ribbon to O or near magnetostriction 0, it is possible to maintain the symmetry of the hysteresis waveform of the amorphous magnetic ribbon. In this case, it is possible to realize a saturable core having a high square shape, low loss, no waveform distortion, and high reliability.

[Brief explanation of drawings]

FIG. 1 is a specific circuit diagram of an embodiment of the present invention, FIG. 2 is an explanatory diagram of the same as the above, and FIG. 3 is an AC magnetic characteristic diagram of an amorphous magnetic ribbon. FIG. 4 is a specific circuit diagram of the conventional example, FIG. 5 is an explanatory diagram of the same, and FIGS. 6(a) and 6(b) are explanatory diagrams of the same operation. ST indicates an oscillation transformer, and C indicates a capacitor. Agent Patent Attorney Ishi 1) Chief 7111 Figure 113 Hijika Rijaku B (KG)

Claims (2)

[Claims] (1) An electromagnetic device comprising an amorphous magnetic ribbon and a demagnetizing means for making the magnetostriction of the amorphous magnetic ribbon zero or close to zero. (2) Form a saturable core with an amorphous magnetic ribbon, configure an oscillation transformer of a blocking oscillation circuit with this saturable core, and connect it between the intermediate lead wire of the primary winding of the oscillation transformer and the ground wire. 2. The electromagnetic device according to claim 1, further comprising a capacitor.