HU183537B - Method and arrangement for making the iron-core of anti-interference filter with wide frequency range - Google Patents

Abstract

The arrangement according to the invention has bobbin bodies, rollers, tubs, insulating and adhesive materials, and heat treatment. The method and arrangement according to the invention can be advantageously used to produce a light control coil core of the light control switches or a coil core of a network interference filter. -1-

Description

As is known, control devices made of semiconductor switching elements (thyristor, triac) are becoming more and more common in industrial and domestic applications. The change of power by means of the switching elements is achieved by switching on the alternating current at different phase points within each half-period at a given supply voltage. The later the power is turned on, the lower the power per consumer. When switched on and off, the downward pressure on the consumer changes abruptly, which causes a sudden change in current. This change is greatest at the 90 ° phase. The steeper the current is after the power is turned on, the more harmonics are generated, which means interference in the radio waves. The voltage spectrum and intensity of the noise depend on the magnitude of the current change and the duration of the switching rise. By using a line interference suppression coil, the rise time is extended from 1 per second to 20-40 psec depending on the magnitude of the inductance and thus the noise spectrum intensity is reduced.

Using L, C noise filters, where inductive impedance dominates capacitance, (x _L > x _c ), the usual formula for noise reduction is:

R-- ~ ω ² > L · C (1)

An example is a dimmer switch which produces 120 dB (rV) noise at 150 kHz without interference suppression.

The allowable level is 70 dB and you need: · Interference suppression is therefore 50 dB. Selecting the capacitor capacitance of the interference suppressor at 0.15 μΡ (higher capacitance would already disturb the switching element with the required inductance 2.3 mH).

Solutions are known which are suitable for making the core material of a filter coil. For example, B 82603-V-B toroidal coils from 1.6 to 16 A, sold by Siemens.

A common feature of these solutions is that the core material consists of known soft magnetic materials or combinations thereof: permalloy, Fe-3,2 Si transformer plate and soft frit. Said Siemens toroidal coil core is, for example, a pair of permalloy and Fe-Si transformer strips; was made by winding it to meet the dual requirements of, on the one hand, high initial permeability (μ;) and, on the other hand, high saturation magnetic field (Hs). The permalloy provides the core material at low currents, while the Fe-Si at high currents (high load); permeability.

A common disadvantage of these known materials is that they are expensive and complicated to produce. The known metallurgical practice produces permalloy and Fe-Si strips by multiple rolling and heat treatment, thereby significantly increasing the cost of production. In addition, the surface of the transformer plate must be individually coated with an insulating layer to reduce eddy current losses.

It is an object of the present invention to eliminate all of the above difficulties and to provide a solution that can be economically manufactured even in small series production with cheap materials and simple technological steps. It is an object of the present invention to accomplish the above objective by making the core material of choice less expensive than the known coil of the same size and providing greater interference suppression.

The invention is based on the finding that the dual requirement (high / ;;, high H, _s) certain metallic glasses satisfy themselves, and in that the coupling elements Interference suppression is proportional to the magnetic energy stored in coils. This energy is increased by optimizing the composition of the metal glass for the highest possible saturation induction, while improving the magnetic properties by magnetic treatment.

Thus, the present invention provides a method and arrangement for producing an interference suppression coil core which provides less expensive, but at the same time higher interference suppression.

The essence of the process according to the invention is to produce a tape with a high saturation magnetization of the desired width and to wrap it with the desired diameter by gluing it with insulation. The toroidal core is heat treated at 100-300 ° C for 1-3 hours so that it

A magnetic field of 5 to 50 A / cm intensity is perpendicular to the toroidal plane. In this way, a directional domain structure is created, which results in a flattening of the magnetization curve, which increases the magnetic energy stored per unit volume. At the same time, the role of domain rotations against domain tree shifts in the magnetization processes of the flatter magnetization curve increases the frequency-independent range of permeability and thus improves the coil suppression capability of the coil. According to the invention, it is expedient to calculate the cross-section of the iron core by multiplying the load-dependent maximum current by the desired interference filtering ratio. The numerical value thus obtained is divided by the product of the maximum induction allowed in the linear approximation multiplied by the number of turns. The numerical value thus obtained is divided by the square of the circular frequency and the value of the capacity used in the filtration. In particular, it is desirable to place the coiled core in a solenoid-shaped heater which produces not only the required temperature but also the magnetic field.

Furthermore, it is preferable to use Feii (ShBvCz), _n as the metal glass. The usual composition is 16am22, 4sxs 12, 8sys 14, 0 ^ zs6. The arrangement according to the invention is characterized in that it comprises threaded bodies, rollers, a bath, and an insulating and gluing material and a heat treatment.

According to the invention, it is expedient for the heat treater to have a solenoid-shaped heater supplied with direct current.

The invention will be described in more detail with reference to the drawing, in which some exemplary embodiments of the known and the present invention are shown. In the drawing it is

Fig. 1 shows an exemplary embodiment of the interference filter coil according to the invention, a

Figure 2 illustrates an exemplary embodiment of a winding arrangement according to the invention,

Figure 3 illustrates an exemplary embodiment of a magnetic heat treatment arrangement according to the invention.

Fig. 1 shows an embodiment of a known interference filter coil having a coil core 11 and a coil 12. The coil has 11 cores placed side by side

-218} 537 is made by winding iron silicon and permalloy tapes, which are subsequently embedded in an adhesive.

An exemplary embodiment of the interference filter coil of the present invention is also illustrated in Figure 1 having a coil core 11 and a coil 12. The coil is made of 11 core metal glass strips in multiple layers fastened with adhesive and insulated.

Fig. 2 shows an exemplary embodiment of a winding arrangement according to the invention, comprising 14,18 reel bodies, 15 rollers, a tub 16 and an insulating pipe 17 adhesive. The strip unwound from the reel body 14 is guided by the roller 15 through the adhesive and insulating material 17 in the tub 16 and is wound onto the reel body 18.

Figure 3 illustrates an exemplary embodiment of the magnetic heat treatment arrangement of the present invention consisting of a heater 13 and a coil core 11. The direct current passing through the radiator 13 produces not only the 100-300 ° C temperature required for the heat treatment, but also the 5 to 50 A / cm magnetic field required for the magnetic heat treatment. During the heat treatment, the axes of the heater 13 and the core core 11 coincide. The usual duration of the heat treatment is 1-3 hours.

Scaling procedure

The formula underlying the cross-sectional dimensioning is derived from the idea that the flux in the coil can be expressed in two ways: by the average inductance I of the coil and the maximum current I passing through the coil; with the help of number of passes:

n-SB-L-I (2)

The relation 2 is valid only in linear approximation, which assumes that the magnetic induction and the rise of the switching current are linear with the magnetic field and with time.

The average inductance is calculated using equation 1 for a frequency of 150 kHz corresponding to the lower limit of the disturbance spectrum, and for a maximum allowable capacitance value (0.15-0.22 pF).

The required interference suppression varies between 50-60 dB (R ** »300-1000), depending on the equipment containing the interference-generating switch. Based on formulas I and 2, the required core cross-section can be calculated using the following formula:

An example is the dimensioning of the interference suppression coil of the 600 W brightness control. In this case:

I = 3.5 A; n-120; B = 1.2 T; R- 50 db (=> 316); f = 150 kHz; C '0.15 pF

From this data, S = 0.68 cm ^{2, with a} 20% incidence, according to formula (3).

The number of turns of the coil shall be chosen such that the copper loss of a given wire of suitable diameter for the current is reasonably small and less than 0.2% of the power of the consumer.

As can be seen, the process and arrangement of the invention allow simple, economical production. The metal glass strip can be produced in a single step, thus eliminating the use of expensive and sophisticated permalloy and Fe-Si strips. By the described dimensioning method, the cross-section of the coil core can be optimally selected, while the applied magneto-heat treatment further improves the magnetic properties and the aging; against. It is important to note that magnetic heat treatment is not always necessary. For example, in the case of a dimmer switch, the test specimens provide the standard noise suppression level required without heat treatment.

Claims (6)

Patent claims A method for making an iron core of a wide frequency range interference suppression coil, comprising coiling the core with a thin ferromagnetic plate, characterized in that the core is wound by gluing, insulating, and using a high-saturation magnetized metal glass strip as the ferromagnetic material. Heat at C for 1-3 hours in a transverse magnetic field at an intensity of 5 to 50 A / cm. Method according to claim 1, characterized in that the cross-section (S) of the iron core is determined by multiplying the load-dependent maximum current value (I) by the desired interference filtering ratio (R) and dividing the resulting numerical value by the product of the maximum induction (B) multiplied by the number of passages (n) in the linear approximation, then dividing the resulting figure by the square of the circular frequency (ω ² ) and the capacity (C) used during the filtration. where I - maximum load dependent current, n - number of runs, usually around 100, B - maximum induction allowed in linear approximation, usually 1.2 T. Experience has shown that a 20% increase in the cross-sectional value based on formula (3) is sufficient, due to the filling factor of less than 1 due to the winding and to the linear approximation. 3. A method according to claim 1, characterized in that the coiled core is placed in a solenoid-shaped heater which produces not only the required temperature but also the magnetic field. 4. A process according to any one of claims 1 to ₄ , wherein the metal3 glass is Feomo (SixB _y C ₂ ) _m , wherein the usual composition is 16msms22, 4sxs122, 8syfil4, O2Z2. 5. Arrangement in Figures 1-4. A method for producing a core of interference suppression coils operating in a wide frequency range, comprising threaded bodies (14, 18), characterized in that the arrangement comprises plate guiding rollers (15), a tub (16), insulating and adhesive material (17) and (Figure 2). 6. An embodiment of the arrangement according to claim 5, characterized in that the heat treater comprises a direct-current-supplied solonide-shaped heater (13) (Fig. 3).