Voltage regulating transformer using magnetic flux diversion

Abstract

The present invention relates to a system for controlling magnetic flux in transformers for output voltage variation without tap switching by contacts and / or semiconductors, according to the principles used today in the prior art.

Description

[0001] MAGNETIC FLUX DIVERSION VOLTAGE REGULATOR TRANSFORMER

[0002] Field of invention

[0003]

[0001] The present invention relates to a magnetic flux control system in transformers, for varying the output voltage, without tap switching, carried out by contacts and / or semiconductors, in accordance with the principles currently used in the state of the art.

[0004] Fundamentals

[0005]

[0002] State-of-the-art AC voltage regulators and stabilizers, such as variovolts or variacs; voltage stabilizers; reactive regulators, and others, largely use the contact switching principle. This principle presents a series of problems, such as: constant maintenance due to contact wear; insertion of harmonics during switching; and lack of continuous voltage variation. This IP aims to develop a technology, magnetic flux control, that corrects these problems, enabling the design of new products that are simpler, cheaper, and have lower maintenance costs. Although we are discussing AC voltage regulators in general, we will place greater emphasis on regulators and stabilizers currently used in medium-voltage power distribution networks.

[0006] State of the art:

[0007]

[0003] Regulation by tap-switching in the primary and / or secondary, using contacts immersed in insulating oil. These regulators have a circuit that samples the AC voltage from the grid and switches contacts in the primary and / or secondary to increase or decrease the output voltage, keeping it close to a predetermined value. These taps do not allow continuous voltage regulation. Since the switching time is not instantaneous and to avoid open-circuit time, a technique of shorting the switching steps is used. First, the adjacent tap is closed and then the current tap is opened. No matter how fast this switching is, noise is generated in the distribution network. To mitigate this problem, an impedance must be used in series with the contacts. In addition, there are other problems, such as oil deterioration and contact wear, reducing the time between maintenance.

[0008]

[0004] Regulation by tap-switching in the primary and / or secondary, using contacts in vacuum interrupters. Although this system does not have the drawback of oil-immersed contacts, it still requires a temporary short circuit between two taps, since the switching time of these interrupters is on the order of 10 ms. The cost of vacuum interrupters is much higher than that of open oil-immersed contacts. Furthermore, the mechanics for switching vacuum interrupters are very complex and expensive. There is a product that uses two solenoids per interrupter, one to close the contact and the other to lock the contact closed. To open the interrupter, a spring is required, which accumulates energy during closing and dissipates this energy when the locking solenoid releases. All of this reduces the product's MTBF;

[0009]

[0005] Tap-switching regulator made by thyristors (Triacs or SCRs). These regulators have the advantage of being able to switch without the need for a temporary short circuit, as they can switch at times of zero current. The drawback is the voltage limitation and the extremely high cost of these components, which are much higher than the contacts. Furthermore, there is a voltage drop in these components, requiring heat dissipation generated by the dissipated power.

[0010]

[0006] Regulator with conduction and / or cut-off angle control, made with thyristors (Triacs or SCRs). This type of regulator does not control the voltage levels in the load, but rather the power. In addition, it generates a large number of harmonics, making its use in the distribution network impossible.

[0011]

[0007] Induction regulator. This type of regulator has technical advantages over other types: continuous variation of output voltage and minimal generation of disturbances and harmonics in the network. The problem with these regulators is their construction. They are built in the same way as a motor. When used as autotransformers, it is difficult to create insulation between coils. Brush contacts or flexible connections are used to make contact with the internal coil (rotor). Due to their construction, they are much more expensive than other techniques, therefore they are rarely used in power distribution networks.

[0012]

[0008] The proposal of this patent application is quite different from the prior art. The basic principle is to control, through armatures mounted on one or more legs of the transformer, the path and intensity of the magnetic flux in each leg of the secondary coils. This control allows for continuous variation of a transformer's output voltage. There is no need for series impedances, and there is no oil contamination. There are no contacts, contact brushes, or flexible cables, significantly increasing the time between failures (MTBF).

[0013] Brief description of the figures

[0014] Figure 1 shows a three-legged ferromagnetic core with an open armature in one of the legs.

[0015] Figure 2 shows the same core as in Figure 1, but with the armature closed.

[0016] Figure 3 shows the same core as in Figure 1, with two coils, mounted on two legs, with the armature open.

[0017] Figure 4 shows the same core as in Figure 1, with two coils, mounted on two legs, with the armature closed.

[0018] Figure 5 shows a ferromagnetic core similar to that shown in Figure 4, but with the armature leg 1.5 times the width of the other two legs.

[0019] Figure 6 shows, in perspective, a ferromagnetic core with three coils, one on each leg, and with the armature open.

[0020] Figure 7 shows a ferromagnetic core with three coils and two armatures, one open and one closed.

[0021] Figure 8 shows a diagram, for simulation, of a transformer, where we can change the coupling factor, (K1), between two coils.

[0022] Figure 9 shows the result of the simulation of the transformer, from figure 8, with the coupling factor, (K1 ), equal to 1. Figure 10 shows the result of the simulation of the transformer, from figure 8, with the coupling factor, (K1 ), equal to 0.75.

[0023] Figure 11 shows the simulation result of the transformer, from figure 8, with the coupling factor, (K1 ), equal to 0.5.

[0024] Figure 12 shows the simulation result of the transformer, from figure 8, with the coupling factor, (K1 ), equal to 0.4.

[0025] Figure 13 shows a diagram, for simulation, of a transformer, with a primary and two secondaries, in counter-phase, where we can change the coupling factors, (K1 ) and (K2), between the primary coil, (B1 ) and the secondary coils, (B2) and (B3), respectively.

[0026] Figure 14 shows the simulation result of the transformer in figure 13, with the coupling factors, (K1 ) and (K2), equal to 1 and 0, respectively.

[0027] Figure 15 shows the simulation result of the transformer in figure 13, with coupling factors, (K1 ) and (K2), equal to 0.75 and 0.25, respectively.

[0028] Figure 16 shows the simulation result of the transformer in figure 13, with coupling factors, (K1 ) and (K2), equal to 0.5 and 0.5, respectively.

[0029] Figure 17 shows a diagram, for simulation, of an autotransformer, with a primary and two secondaries, in counter-phase, all in series, where we can change the coupling factors, (K1) and (K2), between the primary coil, (B1) and the secondary coils, (B2) and (B3), respectively.

[0030] Figure 18 shows the simulation result of the transformer in Figure 17, with the coupling factors, (K1 ) and (K2), equal to 1 and 0, respectively.

[0031] Figure 19 shows the simulation result of the transformer in figure 17, with coupling factors, (K1 ) and (K2), equal to 0.75 and 0.25, respectively.

[0032] Figure 20 shows the result of the simulation of the transformer in Figure 17, with the coupling factors, (K1 ) and (K2), equal to 0.5 and 0.5, respectively. Figure 21 shows a diagram, for simulation, of an autotransformer, with a primary and two secondaries, in counter-phase, all in series, with the secondary, (B3), having twice as many turns as the secondary, (B2), where we can change the coupling factors, (K1 ) and (K2), between the primary coil, (B1 ) and the secondary coils, (B2) and (B3), respectively.

[0033] Figure 22 shows the simulation result of the transformer in figure 21, with coupling factors, (K1) and (K2), equal to 0.5 and 0.5, respectively, presenting an output voltage lower than the input voltage.

[0034] Figure 23 shows the simulation result of the transformer in figure 21, with the coupling factors, (K1) and (K2), equal to 0 and 1, respectively, presenting an output voltage greater than the input voltage.

[0035] Figure 24 shows a schematic, for simulation, of an autotransformer, with one primary and two secondaries, in counter-phase, all in series, where we can change the coupling factors, (K1 ) and (K2), between the primary coil, (B1 ) and the secondary coils, (B2) and (B3), respectively. This simulation refers to the use of two armatures.

[0036] Figure 25 shows the simulation result of the transformer in figure 24, with the coupling factors, (K1 ) and (K2), equal to 0 and 1, respectively, presenting an output voltage lower than the input voltage.

[0037] Figure 26 shows a diagram, for simulation, of a simple transformer, with a primary, (B1 ) and a secondary, (B2), where we can, by using two armatures, as shown in figure 7, take the coupling factor, (K1 ), between the primary coil, (B1 ) and the secondary coil, (B2), to 0, showing the disconnection of the secondary, (B2).

[0038] Figure 27 shows the simulation result of the transformer in figure 25, with the coupling factor, (K1 ), equal to 0, presenting an output voltage equal to 0.

[0039] Description of the principle

[0040]

[0009] To describe the principle of the patent, we will use figures 1 to 7 as support. We will not take into account the normal losses of a transformer, such as: dispersion; eddy current losses; reluctance; and others. The basic principle of this patent is the construction of a core, N, with three legs, P1, P2, and P3. Leg P3 is interrupted by an armature, Idz, which can be moved angularly. The armature can be positioned continuously between the open leg position (figure 1) and the closed leg position (figure 2). On the legs, P1 and P2, coils, B1, primary, and B2, secondary, are wound. When the armature, Idz, is open (figure 3), all the flux, Fxp, generated by the primary coil, B1, will circulate through the secondary coil, B2.As the armature, Idz, rotates and penetrates leg P3, the primary flux, Fxp, begins to divide between legs P2 and P3, creating the secondary fluxes, Fsx1 and Fsx2, until the armature, Idz, closes 100% of leg P3, dividing the primary flux, Fxp, by two (Figure 4). In this condition, the secondary coil, B2, will receive only half of the flux generated by the primary coil, B1. By varying the position of the armature, Idz, we will have a variation in the induced voltage in the secondary coil, B2. To reduce the flux in the secondary coil, B2, leg P2, below 50%, we can increase the cross-sectional area of ​​leg P3 (Figure 5). We can also wind a secondary coil, B3, on leg P3, and make additions and / or subtractions of voltage from the secondary coils, B2 and B3, (figure 6).We can place two armatures, Idz1 and Idz2, in legs P2 and P3, allowing total flux control, being able to divide the flux generated by the primary coil, B1, in any proportion, between the secondary coils, B2 and B3. We can also have only two legs, P1 and P2, in the core, N, with an armature in leg P2, but when the armature is open, all the flux generated in B1 will be dispersed, which can generate a lot of interference in nearby equipment.

[0041] Description

[0042]

[0010] Below, we present, with the support of figures 8 to 27, some ways of implementing the principles of this patent. All graphs show the voltage in the primary coil, B1, in red and the output voltage in green.

[0043]

[0011] Figure 8 shows the schematic of a simple transformer, with a primary coil, B1, and a secondary coil, B2, as shown in figure 4, with the possibility of regulating the output voltage, used to make a simulation. As can be seen in figure 4, the minimum coupling between the primary, B1, and secondary, B2, is 0.5 (K1 = 0.5), when the armature, Idz, is fully closed, dividing the primary flux, Fxp, by two. In this case, the output voltage regulation cannot be zeroed.

[0044]

[0012] Figure 9 shows the result of the simulation of the transformer, from figure 8, with the coupling factor of 100%, (K1 = 1 ), induced, Idz, fully open. In this configuration, all the flux, Fxp, generated by the primary coil, B1, circulates through the secondary coil, B2, as shown in figure 3, generating the maximum output voltage, in the secondary coil, B2.

[0045]

[0013] Figure 10 shows the simulation result of the transformer of Figure 8, with the coupling factor of 75%, K1 = 0.75. In this configuration, 25% of the flux, FxP, generated by the primary coil, B1, was diverted to the leg P3, by the partial closing of the armature, Idz, generating a decrease in the output voltage, secondary coil, B2.

[0046]

[0014] Figure 11 shows the simulation result of the transformer of Figure 8, with the coupling factor of 50%, K1 = 0.5. In this configuration, 50% of the flux, FxP, generated by the primary coil, B1, was diverted to the leg P3, by the total closure of the armature, Idz, generating the lowest possible output voltage, in the secondary coil, B2, as shown in Figure 4.

[0047]

[0015] Figure 12 shows the simulation result of the transformer in Figure 8, with a coupling factor of 40%, K1 = 0.4. In this configuration, 60% of the flux, FxP, generated by the primary coil, B1, was diverted to leg P3, by the complete closure of the armature, Idz, generating the lowest possible output voltage in the secondary coil, B2, as shown in Figure 5. This reduction, below 50%, of the coupling value, was only possible by increasing the cross-section of leg P3, as can be seen in Figure 5. It is possible to further increase the cross-section of leg P3, to further reduce the output voltage, but, in this configuration, with only one armature and a single secondary, we cannot generate zero voltage in the secondary coil, B2.

[0048]

[0016] Figure 13 shows the schematic of a transformer, with a primary coil, B1, two secondary coils, B2 and B3, with the same number of turns, and an armature, Idz, as shown in Figure 6. The secondary coils, B2 and B3, are in series, so the output voltage is equal to the sum of the voltages of these two coils, B2 and B3. Since the secondary coils, B2 and B3, are in counter-phase, when the armature, Idz, is 100% closed, dividing the flux, Fxp, 50% for each secondary, the output voltage will be zero. This configuration allows the construction of a “variac”, which can have an output voltage varying from zero to a maximum voltage. This diagram shows two couplers, K1, which couples the primary coil, B1, to the secondary coil, B2, and K2, which couples the primary coil, B1, to the secondary coil, B3. The coupling factors K1 = 1 and K2 = 0 are represented in Figure 6, where 100% of the flux, Fxp, generated by the primary coil, B1, passes through the secondary coil, B2.The sum of the coupling factors, K1 and K2, are always equal to 1. The coupling factor K1 can vary from 1 to 0.5, while the coupling factor K2 can vary from 0 to 0.5, always with the sum equal to 1.

[0049]

[0017] Figure 14 shows the simulation of the circuit in figure 13, with coupling factors K1 = 1 and K2 = 0, armature, Idz, fully open, as shown in figure 6. In this configuration the output voltage is maximum.

[0050]

[0018] Figure 15 shows the simulation of the circuit in figure 13, with coupling factors K1 = 0.75 and K2 = 0.25, armature, Idz, partially closed. We can see in this simulation that the output voltage has decreased, in relation to the voltage shown in figure 14.

[0051]

[0019] Figure 16 shows the simulation of the circuit in Figure 13, with coupling factors K1 = 0.5 and K2 = 0.5, armature, Idz, fully closed. In this condition, the voltages in the secondary coils, B2 and B3, are equal, but 180 degrees out of phase, causing the output voltage to be equal to zero.

[0052]

[0020] Figure 17 shows the schematic of an autotransformer, with a primary coil, B1, two secondary coils, B2 and B3, with the same number of turns, and an armature, Idz, as shown in Figure 6. All coils, B1, B2, and B3, are in series. Coils B2 and B3 are in counter-phase. The output voltage is equal to the sum of the voltages of the three coils, B1, B2, and B3. This configuration allows the construction of a voltage regulator, which can have an output voltage varying from the input voltage up to a maximum voltage. This schematic shows two couplers, K1, which couples the primary coil, B1, to the secondary coil, B2, and K2, which couples the primary coil, B1, to the secondary coil, B3. The coupling factors K1 = 1 and K2 = 0 are represented in figure 6, where 100% of the flux, Fxp, generated by the primary coil, B1, passes through the secondary coil, B2. The sum of the coupling factors, K1 and K2, are always equal to 1.The coupling factor K1 can vary from 1 to 0.5, while the coupling factor K2 can vary from 0 to 0.5, always with the sum equal to 1.

[0053]

[0021] Figure 18 shows the result of the simulation of the circuit in Figure 17 with the coupling factors K1 = 1 and K2 = 0. This condition occurs when the armature, Idz, is fully open, as shown in Figure 6, causing 100% of the magnetic flux generated in the primary coil, B1, to circulate through the secondary coil, B2. The graph shows that the output voltage is greater than the input voltage. This voltage is the maximum that can be achieved.

[0054]

[0022] Figure 19 shows the result of the simulation of the circuit in Figure 17 with the coupling factors K1 = 0.75 and K2 = 0.25. This condition occurs when the armature, Idz, in Figure 6, is partially closed, causing the magnetic flux generated in the primary coil, B1, to divide and circulate, 75% through leg P2, secondary coil B2, and 25% through leg P3, secondary coil B3. We can see that the output voltage is greater than the input voltage, but lower than the output voltage, shown in Figure 18.

[0055]

[0023] Figure 20 shows the simulation result of the circuit in Figure 17, with coupling factors K1 = 0.5 and K2 = 0.5. This condition occurs when the armature, Idz, in Figure 6, is fully closed, causing the magnetic flux generated in the primary coil, B1, to divide and circulate 50% through leg P2, secondary coil B2, and 50% through leg P3, secondary coil B3. We can see that the output voltage is equal to the input voltage, since the sum of the voltages of the secondaries, B2 and B3, is equal to zero. This configuration, in Figure 6, with the armature, Idz, fully closed, shows the lowest output voltage we can have, an output voltage equal to the input voltage. Therefore, this regulator does not allow obtaining an output voltage lower than the input voltage, not serving, for example, as a power distribution regulator.

[0024] Figure 21 shows the schematic of an autotransformer, with a primary coil, B1, two secondary coils, B2 and B3, but with the secondary coil, B3, having twice as many turns as the secondary coil, B2, and an armature, Idz, as shown in Figure 6. All coils, B1, B2 and B3 are in series. Coils B2 and B3 are in counter-phase. The output voltage is equal to the sum of the voltages of the three coils, B1, B2 and B3. This configuration allows the construction of a voltage regulator, which can have an output voltage lower than the input voltage. This schematic shows two couplers, K1 that couples the primary coil, B1 to the secondary coil, B2, and K2 that couples the primary coil, B1, to the secondary coil, B3. The coupling factors K1 = 1 and K2 = 0 are represented in figure 6, where 100% of the flux, Fxp, generated by the primary coil, B1, passes through the secondary coil, B2. The sum of the coupling factors, K1 and K2, are always equal to 1.The coupling factor K1 can vary from 1 to 0.5, while the coupling factor K2 can vary from 0 to 0.5, always with the sum equal to 1.

[0056]

[0025] Figure 22 shows the simulation result of the circuit in Figure 21, with coupling factors K1 = 0.5 and K2 = 0.5. This condition occurs when the armature, Idz, in Figure 6, is fully closed, causing the magnetic flux generated in the primary coil, B1, to divide and circulate 50% through leg P2, secondary coil B2, and 50% through leg P3, secondary coil B3. We can see that the output voltage is lower than the input voltage, since the output voltage is equal to the input voltage plus the sum of the voltages in the secondary coils, B2 and B3. Since the secondary coil, B3, has twice as many turns as the secondary coil, B2, and is in counter-phase with it, the sum of these two voltages is negative in relation to the input voltage, causing the output voltage to be lower than the input voltage, which is not achieved when these coils have the same number of turns.

[0057]

[0026] Figure 23 shows the simulation result of the circuit in Figure 21, with coupling factors K1 = 1 and K2 = 0. This condition occurs when the armature, Idz, in Figure 6, is fully open. Since there is no flux passing through the secondary coil, B3, its voltage is zero, so the output voltage is equal to the input voltage plus the voltage of the secondary coil, B2. This scheme, in Figure 21, allows the construction of a voltage regulator, where the output voltage can be greater or less than the input voltage, and can be calculated for use in the power distribution network.

[0058]

[0027] Figure 24 shows the diagram of an autotransformer, with a primary coil, B1, two secondary coils, B2 and B3, with the same number of turns, and two armatures, Idz1 and Idz2, mounted on the legs, P2 and P3, respectively, as shown in the core of figure 7. In this configuration we can have the magnetic flux, Fxp, generated by the primary coil, B1, being totally diverted (100%), to the secondary coil, B3, as shown in figure 7. The couplers, K1 and K2, can vary from 0 to 1, but always with the sum equal to 1. Figure 7 shows K1 = 0 and K2 = 1.

[0059]

[0028] Figure 25 shows the simulation result of the circuit in Figure 24, with coupling factors K1=0 and K2=1, as shown in Figure 7. This condition occurs when the armature, Idz1, in Figure 7, is fully open. Since there is no flux passing through the secondary coil, B2, its voltage is zero, so the output voltage is equal to the input voltage plus the voltage of the secondary coil, B3. Since the secondary coil, B3, is in counter-phase with the primary coil, B1, and secondary coil, B2, the output voltage will be equal to the input voltage minus the voltage of the secondary coil, B3, as can be seen in the simulation result, with an output voltage lower than the input voltage. This scheme, in Figure 24, allows the construction of a voltage regulator, where the output voltage can be greater or less than the input voltage, and can be calculated for use in the power distribution network.

[0060]

[0029] Figure 26 shows the diagram of a transformer, with a primary coil, B1, a secondary coil, B2, and two armatures, Idz1 and Idz2, as shown in figure 7, showing that the invention can also be used as an on and off switch, where we can have the output voltage equal to zero.

[0061]

[0030] Figure 27 shows the result of the simulation of the circuit of figure 26, when the armature, Idz1, is open and Idz2 is closed, as shown in figure 7. In this condition the output voltage, in coil B2, load R3, is equal to zero. Coil B3 was not used. This assembly can be used to manufacture transformers with cut-off and even contactless reclosers.

[0062]

[0031] As can be seen in the figures with their descriptions, the principle of magnetic flux deviation can be used to manufacture various products, such as: voltage variators and / or variacs; voltage regulating transformers for the power distribution network; voltage cutting transformers for the power distribution network; recloser transformers for the power distribution network; regulating transformers for reactive compensation; voltage regulating autotransformers for the power distribution network;

[0063]

[0032] Although we are presenting a well-defined construction form, to facilitate understanding, we can have variations, without straying from the principles presented here (deviation of magnetic flux), such as: the armature having a straight cut and its movement being linear, on the x, y and z axes; the legs, P1, P2 and P3, of the core, N, having different cross sections; and so on.

Claims

CLAIMS 1. MAGNETIC FLUX DIVERSION VOLTAGE REGULATOR TRANSFORMER, for AC voltage regulators, without the use of tap switching contacts, without brushes or flexible cables, characterized by having: - a ferromagnetic core, N, with two legs, P1, P2, continuous, and one leg P3, with an interruption, where an armature, Idz, is mounted, which diverts part of the flux, Fxp, generated by the primary coil, B1, from leg P2 to leg P3, regulating the voltage of the secondary coil, B2.

2. MAGNETIC FLUX DIVERSION VOLTAGE REGULATOR TRANSFORMER, for AC voltage regulators, without the use of tap switching contacts, without brushes or flexible cables, as per claim 1, characterized by: - have a P3 leg, with a different transverse yield than the P1 and P2 legs.

3. MAGNETIC FLUX DIVERSION VOLTAGE REGULATOR TRANSFORMER, for AC voltage regulators, without the use of tap switching contacts, without brushes or flexible cables, as per claim 1, characterized by: - have a second secondary coil, B3, wound on leg P3.

4. MAGNETIC FLUX DIVERSION VOLTAGE REGULATOR TRANSFORMER, for AC voltage regulators, without the use of tap switching contacts, without brushes or flexible cables, characterized by having: - a ferromagnetic core, N, with one leg, P1, continuous, and two legs, P2 and P3, with interruptions, where the armatures, Idz1 and Idz2, are mounted, respectively, which divert up to 100% of the flux, Fxp, generated by the primary coil, B1, from leg P2 to leg P3, regulating the voltage of the secondary coils, B2 and B3.

Images