KR20200124152A - Current compensation device - Google Patents

Abstract

Embodiments of the present invention relate to a current compensation device which actively compensates for a first current inputted from one device in a common mode to minimize the influence on other devices in various types of power systems. According to the present invention, the current compensation device includes: at least two or more high current paths for passing a second current supplied by a second device to a first device; a sensing unit having a through opening, into which at least two or more high current paths are inserted, and sensing a first current on at least two or more high current paths to generate an output signal corresponding to the first current; an amplification unit which amplifies the output signal to generate an amplified signal; a compensation unit which generates a compensation current based on the amplified signal; and a compensation capacitor unit providing a path through which compensation current flows in each of at least two or more high current paths.

Description

Current compensation device {CURRENT COMPENSATION DEVICE}

Embodiments of the present invention relate to a current compensating device, and to a current compensating device for actively compensating a current input in a common mode on two or more large current paths connecting two devices.

In general, electrical devices such as home appliances, industrial electrical appliances, and electric vehicles emit noise during operation. For example, noise may be generated due to the switching operation inside the electric device. Such noise is not only harmful to the human body, but also causes malfunction or failure of other connected electronic devices.

Electromagnetic interference from an electronic device to other devices is referred to as EMI (Electromagnetic Interference), and among them, noise transmitted through wires and board wiring is referred to as Conducted Emission (CE) noise.

In order to ensure that electronic devices operate without causing breakdowns in peripheral components and other devices, EMI noise emission levels are strictly regulated in all electronic products. Accordingly, most electronic products essentially include a current compensating device such as an EMI filter that reduces EMI noise in order to satisfy the regulation on the amount of noise emission.

For example, in white goods such as air conditioners, electric vehicles, aviation, energy storage systems (ESS), and the like, a current compensation device is essentially included. A conventional current compensating device uses a common mode choke to reduce common mode (CM) noise among conductive emission (CE) noise.

Meanwhile, as high-power products are released, the needs for current compensation devices for high-power systems are increasing. However, in a high power/high current system, the common mode (CM) choke rapidly deteriorates noise reduction performance due to self-saturation. Therefore, in order to prevent magnetic saturation and maintain noise reduction performance in high power/high current systems, conventionally, the size and number of common mode chokes have to be increased or the number of common mode chokes has to be increased. There was a problem.

In particular, in a high power/high current system, a thick copper plate in the form of a bus bar is used for the path (or winding) through which the current flows. In this case, it is limited to wind the winding several times in the sensing unit that senses the current flowing through the winding in order to actively remove noise. In addition, when the thick copper plate is wound several times, there is a problem that the size of the sensing unit increases and the overall size of the current compensating device is greatly increased.

The present invention is to improve the above problems, and to provide an active current compensation device that reduces common mode (CM) noise.

In addition, the present invention is to improve the above problems, to reduce the size of the sensing unit, and to provide an active current compensation device with increased productivity.

However, these problems are exemplary, and the scope of the present invention is not limited thereby.

A current compensating device for actively compensating for a first current input in a common mode to each of at least two or more high current paths connected to a first device according to an embodiment of the present invention is provided by the second device. At least two or more high current paths for passing a second current to the first device; A sensing unit having a through opening, the at least two large current paths being inserted into the through opening, sensing the first current on the at least two large current paths, and generating an output signal corresponding to the first current; An amplification unit for amplifying the output signal to generate an amplified signal; A compensation unit that generates a compensation current based on the amplified signal; And a compensation capacitor unit providing a path through which the compensation current flows through each of the at least two large current paths.

In addition, the sensing unit may be configured as a sensing transformer including a core having the through opening and generating the output signal based on a magnetic flux density generated by the first current on the at least two high current paths. .

In addition, the core has a clamp structure capable of opening and closing, and each of the at least two or more high current paths may be inserted into the inner side in an open state.

In addition, the amplification unit may include a first amplifying element for amplifying a positive signal; A second amplifying element for amplifying a negative signal; And at least one impedance controlling an amplification ratio of the first amplifying element and the second amplifying element.

In addition, each of the first amplifying element and the second amplifying element includes a bipolar junction transistor (BJT), and the at least one impedance is connected to the emitter terminal of the BJT of the first amplifying element and the second amplifying element. A first impedance (Z1); And a second impedance Z2 connected to the base terminal of the BJT of the first amplifying element and the second amplifying element, wherein the first impedance Z1 and the second impedance Z2 are the sensing unit and The amplification ratio of the first amplifying element and the second amplifying element may be adjusted based on the current amplification degree of the compensation unit.

In addition, when the current amplification degree of the sensing unit is 1/F1 and the current amplification degree of the compensation unit is 1/F2, the first impedance Z1 and the second impedance Z2 are F1*F2 It is possible to adjust the amplification ratio of the first amplifying element and the second amplifying element to be.

Other aspects, features, and advantages other than those described above will become apparent from the detailed content, claims and drawings for carrying out the following invention.

According to various embodiments of the present invention made as described above, it is possible to provide a current compensation device that does not significantly increase in price, area, volume, and weight even in a high power system.

The current compensating device according to various embodiments of the present disclosure may reduce price, area, volume, and weight compared to a passive compensating device including a CM choke.

In addition, the current compensating device according to various embodiments of the present disclosure may provide an active current compensating device capable of independently operating without parasitic to a CM choke.

In addition, the current compensation device according to various embodiments of the present disclosure may have an active circuit terminal electrically insulated from a power line, thereby stably protecting elements included in the active circuit stage.

In particular, according to the present invention, by simply passing the winding through the core without having to wind the winding (or high current path) around the core (or sensing transformer), the number of times (or turns) that the winding passes through the core can be greatly reduced, and thus The size of the sensing unit can be greatly reduced. In particular, in a three-phase, four-wire power system, the size of the sensing unit can be further drastically reduced.

According to the present invention, the productivity of a product using a high power/high current system can be dramatically increased by significantly reducing the number of times the winding passes through the core.

According to the present invention, as the number of turns and inductance toward the power line decreases, the risk of magnetic saturation is greatly reduced, and the amount of increase in the core size according to the increase in power can also be greatly reduced.

The above-described effects are listed by way of example, and the effects of the present invention are not limited thereto.

1 is a diagram schematically showing a configuration of a system including a current compensating device 100 according to an embodiment of the present invention.
2 is a diagram schematically showing a configuration of a current compensation device 100A used in a second line system according to an embodiment of the present invention.
3A and 3B are diagrams for explaining an operation when the sensing unit 120 is implemented as a sensing transformer 120A according to an embodiment of the present invention.
4A and 4B are diagrams for explaining that the sensing unit 120 according to an embodiment of the present invention is implemented as a sensing transformer 120A in which a high current path is wound once.
5A and 5B are diagrams for explaining that the amplifying unit 130A according to an embodiment of the present invention is implemented with a Bipolar Junction Transistor (BJT) and a plurality of passive elements.
6A and 6B are diagrams for explaining a feedback amplifier capable of freely designing an amplification degree according to an embodiment of the present invention.
7 is a diagram for explaining the currents IL1 and IL2 flowing through the compensation capacitor unit 150A.
8 is a diagram schematically showing a configuration of a current compensation device 100B according to another embodiment of the present invention.
9 is a diagram schematically showing the configuration of a current compensating device 100C according to another embodiment of the present invention.
10 is a diagram schematically showing the configuration of a system in which the current compensation device 100B according to the embodiment shown in FIG. 8 is used.

Since the present invention can apply various transformations and can have various embodiments, specific embodiments are illustrated in the drawings and will be described in detail in the detailed description. Effects and features of the present invention, and a method of achieving them will be apparent with reference to the embodiments described later in detail together with the drawings. However, the present invention is not limited to the embodiments disclosed below and may be implemented in various forms.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, and when describing with reference to the drawings, the same or corresponding components are assigned the same reference numerals, and redundant descriptions thereof will be omitted. .

In the following embodiments, terms such as first and second are not used in a limiting meaning, but are used for the purpose of distinguishing one component from another component. In the following examples, the singular expression includes the plural expression unless the context clearly indicates otherwise. In the following embodiments, terms such as include or have means that the features or elements described in the specification are present, and do not preclude the possibility of adding one or more other features or elements in advance. In the drawings, components may be exaggerated or reduced in size for convenience of description. For example, the size and shape of each component shown in the drawings are arbitrarily shown for convenience of description, and thus the present invention is not necessarily limited to what is shown.

1 is a diagram schematically showing a configuration of a system including a current compensating device 100 according to an embodiment of the present invention.

The current compensation device 100 according to an embodiment of the present invention includes a first current I11 inputted in a common mode to each of at least two or more high current paths 111 and 112 connected to the first device 300. , I12) can be actively compensated. To this end, the current compensation device 100 according to an embodiment of the present invention includes at least two or more high current paths 111 and 112, a sensing unit 120, an amplifying unit 130, a compensation unit 140, and a compensation capacitor unit ( 150) may be included.

Two or more high current paths 111 and 112 may be paths for transferring the second currents I21 and I22 supplied by the second device 200 to the first device 300 within the current compensating device 100. However, it may be, for example, a power line. According to an embodiment, each of the two or more high current paths 111 and 112 may be a live line and a neutral line. For example, the high current paths 111 and 112 may be implemented through a thick copper plate or the like in a high voltage/high power system (for example, an electric vehicle).

In the present specification, the second device 200 may be various types of devices for supplying power to the first device 300 in the form of current and/or voltage. For example, the second device 200 may be a device that produces and supplies power, or may be a device that supplies power generated by another device (eg, an electric vehicle charging device). Of course, the second device 200 may be a device that supplies stored energy. However, this is an example and the spirit of the present invention is not limited thereto.

In this specification, the first device 300 may be various types of devices that use power supplied by the second device 200 described above. For example, the first device 300 may be a load that is driven using power supplied by the second device 200. In addition, the first device 300 may be a load (eg, an electric vehicle) that stores energy using power supplied by the second device 200 and is driven using the stored energy. However, this is an example and the spirit of the present invention is not limited thereto.

As described above, each of the two or more high current paths 111 and 112 may be a path for delivering power supplied by the second device 200, that is, the second current I21 and I22 to the first device 300. However, according to an embodiment, the second currents I21 and I22 may be AC currents having a frequency in the second frequency band. At this time, the second frequency band may be, for example, a band having a range of 50Hz to 60Hz.

In addition, each of the two or more high current paths 111 and 112 may be a path through which noise generated by the first device 300, that is, at least a part of the first currents I11 and I12, is transmitted to the second device 200. At this time, the first currents I11 and I12 may be input to each of the two or more large current paths 111 and 112 in a common mode.

The first currents I11 and I12 may be currents unintentionally generated in the first device 300 due to various causes. For example, the first currents I11 and I12 may be noise currents generated by a virtual capacitance between the first device 300 and the surrounding environment.

The first currents I11 and I12 may be currents having a frequency in the first frequency band. In this case, the first frequency band may have a higher frequency band than the aforementioned second frequency band, for example, may be a band having a range of 150 KHz to 30 MHz.

Meanwhile, two or more high current paths 111 and 112 may include two paths as shown in FIG. 1, or may include three paths or four paths as shown in FIGS. 8 and 9. . The number of high current paths 111 and 112 may vary according to the type and/or type of power used by the first device 300 and/or the second device 200.

Meanwhile, the sensing unit 120 may sense the first currents I11 and I12 on two or more large current paths 111 and 112 and generate an output signal corresponding to the first currents I11 and I12. In other words, the sensing unit 120 may mean a means for sensing the first currents I11 and I12 on the high current paths 111 and 112.

According to an embodiment, the sensing unit 120 may have a through opening into which at least two or more high current paths are inserted. The sensing unit 120 may sense a first current on at least two inserted high current paths and generate an output signal corresponding to the sensed first current.

In one embodiment, the sensing unit 120 may be implemented as a sensing transformer including a core having a through opening and generating an output signal based on a magnetic flux density generated by a first current on at least two high current paths. have. At this time, the core has a clamp structure capable of opening and closing, and may be implemented such that each of at least two or more large current paths is inserted into the inner side in an open state.

In the present invention, the'clamp structure' may mean a structure configured to open and close an outer part of the core. For example, the outer portion of the core of the clamp structure may be configured such that the high current paths 111 and 112 are inserted into the through openings in an open state. Thereafter, an outer portion of the open core may be closed so that the inserted high current paths 111 and 112 cannot be separated.

However, the description of the sensing unit 120 as described above is exemplary, and the spirit of the present invention is not limited thereto. Accordingly, the current sensing means coupled with the path (or conductor) in a form in which the path (or conductor) through which the current to be sensed flows is'inserted' may be used as the sensing unit 120 of the present invention without limitation.

According to an embodiment, the sensing unit 120 may be differentially connected to an input terminal of the amplifying unit 130 to be described later.

The amplification unit 130 may amplify the output signal output from the sensing unit 120 to generate an amplified signal. In the present invention,'amplification' by the amplification unit 130 may mean adjusting the size and/or phase of the amplification target.

By the amplification of the amplification unit 130, the current compensation device 100 generates compensation currents IC1 and IC2 having the same magnitude as the first currents I11 and I12 and opposite to the phase to generate the high current paths 111 and 112. ) Phase may compensate for the first currents I11 and I12.

The amplification unit 130 may be implemented by various means. In one embodiment, the amplification unit 130 may include an OP-AMP. In another embodiment, the amplification unit 130 may include a plurality of passive elements such as a resistor and a capacitor in addition to the OP-AMP. In another embodiment, the amplifying unit 130 may include at least one amplifying element including a Bipolar Junction Transistor (BJT) and a passive element (eg, a resistor, a capacitor, etc.). For example, the amplification unit 130 of the present invention may include a push-pull amplifier in which an npn type BJT and a pnp type BJT are connected in series.

According to an embodiment of the present invention, the amplifying unit 130 may include at least one impedance for adjusting an amplification ratio of the amplifying element. However, the above implementation method of the amplification unit 130 is exemplary, and the spirit of the present invention is not limited thereto, and the means for'amplification' described in the present invention is used without limitation as the amplification unit 130 of the present invention. I can. A detailed description of the amplification unit 130 will be described later with reference to FIGS. 6A to 6B.

On the other hand, the amplification unit 130 receives power from the first device 300 and/or the third device 400 that is separated from the second device 200, amplifies the output signal output by the sensing unit, and thus generates an amplified current. Can be generated. In this case, the third device 400 may be a device that receives power from a power source independent of the first device 300 and the second device 200 and generates input power to the amplifying unit 130. Optionally, the third device 400 may be a device that receives power from any one of the first device 300 and the second device 200 and generates input power of the amplifying unit 130, for example. For example, the third device 400 may be a device that applies DC power. .

The compensation unit 140 is electrically connected to the amplifying unit 130 and may generate a compensation current based on the output signal amplified by the amplifying unit 130 described above.

The compensation unit 140 may be electrically connected to a path connecting the output terminal of the amplifying unit 130 and the reference potential (reference potential 2) of the amplifying unit 130 to generate a compensation current. The compensation unit 140 may be electrically connected to a path connecting the compensation capacitor unit 150 and the reference potential (reference potential 1) of the current compensation device 100. The reference potential (reference potential 2) of the amplifying unit 130 and the reference potential (reference potential 1) of the current compensating device 100 may be different potentials.

The compensation capacitor unit 150 may provide a path through which the compensation current generated by the compensation unit 140 flows through each of two or more large current paths.

According to an embodiment, the compensation capacitor unit 150 may be implemented as a compensation capacitor unit 150 that provides a path through which the current generated by the compensation unit 140 flows to each of two or more large current paths 111 and 112. have. In this case, the compensation capacitor unit 150 may include at least two compensation capacitors connecting the reference potential (reference potential 1) of the current compensation device 100 and the two or more high current paths 111 and 112, respectively.

The current compensating device 100 configured as described above can detect a current of a specific condition on two or more high current paths 111 and 112 and actively compensate for it, and despite the miniaturization of the device 100, high current, high voltage and/or Or it can be applied to high power systems.

Hereinafter, a current compensation device 100 according to various embodiments will be described with reference to FIGS. 2 to 10 together with FIG. 1.

2 is a diagram schematically showing the configuration of a current compensating device 100A used in a second line system according to an embodiment of the present invention.

The current compensating device 100A according to an embodiment of the present invention actively applies the first currents I11 and I12 input in a common mode to each of the two large current paths 111A and 112A connected to the first device 300A. It can be compensated with.

To this end, the current compensation device 100A according to an embodiment of the present invention includes two large current paths 111A and 112A, a sensing transformer 120A, an amplification unit 130A, a compensation transformer 140A, and a compensation capacitor unit 150A. ) Can be included.

In one embodiment, the above-described sensing unit 120 may include a sensing transformer 120A. At this time, the sensing transformer 120A may be a means for sensing the first currents I11 and I12 on the high current paths 111A and 112A in a state insulated from the high current paths 111A and 112A.

The sensing transformer 120A is on the first side 121A disposed on the high current paths 111A and 112A, based on the first magnetic flux density induced by the first currents I11 and I12, and the second side ( 122A) can generate a first induced current. At this time, the second side 122A of the sensing transformer 120A may be differentially connected to the input terminal of the amplifying unit 130 to be described later.

3A and 3B are views for explaining an operation when the sensing unit 120 is implemented as a sensing transformer 120A according to an embodiment of the present invention.

In particular, FIG. 3A is a diagram for explaining a principle in which the sensing transformer 120A generates the first induced current ID1.

For convenience of explanation, it is assumed that the primary side 121A and the secondary side 122A of the sensing transformer 120A are configured as shown in FIG. 3A. In other words, it will be described on the premise that the windings of the high current paths 111A and 112A and the secondary side 122A are wound around the core 123A of the sensing transformer 120A in consideration of the direction in which the magnetic flux and/or the magnetic flux density are generated.

As the first current I11 is input to the high current path 111A, a magnetic flux density B11 may be induced in the core 123A. Similarly, as the first current I12 is input to the high current path 112A, the magnetic flux density B12 may be induced in the core 123A.

The first induced current ID1 may be induced in the winding of the second secondary side 122A by the induced magnetic flux densities B11 and B12.

In this way, the sensing transformer 120A is configured so that the first magnetic flux densities B11 and B12 induced by the first currents I11 and I12 can overlap each other (or reinforce each other), so that two or more high current paths A first induced current ID1 corresponding to the first currents I11 and I12 may be generated at the second secondary side 122A insulated from the 111A and 112A.

Meanwhile, the sensing transformer 120A may be configured such that the second magnetic flux density induced by the second currents I21 and I22 flowing through each of the two or more large current paths 111A and 112A satisfies a predetermined magnetic flux density condition.

3B is a diagram for describing second magnetic flux densities B21 and B22 induced in the sensing transformer 120A by the second currents I21 and I22.

As in FIG. 3A, a description will be made on the premise that the primary side 121A and the secondary side 122A of the sensing transformer 120A are configured as shown in FIG. 3B. In other words, it is assumed that the core 123A of the sensing transformer 120A has two or more high-current paths 111A and 112A and the secondary side 122A winding in consideration of the direction of generation of magnetic flux and/or magnetic flux density. do.

As the second current I21 is input to the high current path 111A, a magnetic flux density B21 may be induced in the core 123A. Similarly, as the second current I22 is input (or output) to the high current path 112A, the magnetic flux density B22 may be induced in the core 123A.

The sensing transformer 120A is configured such that the second magnetic flux density B21 and B22 induced by the second current I21 and I22 (flowing in each of two or more large current paths 111A and 112A) satisfy a predetermined magnetic flux density condition. Can be configured. In this case, the predetermined magnetic flux density condition may be a condition that cancels each other as shown in FIG. 3B.

In other words, in the sensing transformer 120A, the second induced current ID2 induced by the second current I21 and I22 flowing through each of the two or more large current paths 111A and 112A satisfies a predetermined second induced current condition. Can be configured to In this case, the predetermined second induced current condition may be a condition in which the magnitude of the second induced current ID2 is less than a predetermined threshold magnitude.

In this way, the sensing transformer 120A is configured so that the second magnetic flux densities B21 and B22 induced by the second currents I21 and I22 cancel each other, so that only the first currents I11 and I12 are sensed. I can.

The sensing transformer 120A has a second magnetic flux density B11 and B12 induced by the first currents I11 and I12 in a first frequency band (for example, a band having a range of 150 KHz to 30 MHz). It may be configured to be larger than the magnitude of the second magnetic flux densities B21 and B22 induced by the second currents I21 and I22 in the frequency band (for example, a band having a range of 50Hz to 60Hz).

In the present invention, when component A is'configured' to be B, it may mean that the design parameter of component A is set to be appropriate for B. For example, the sensing transformer 120A is configured to have a large magnetic flux induced by a current in a specific frequency band, such as the size of the sensing transformer 120A, the diameter of the core, the number of turns, the size of the inductance, and the size of the mutual inductance. It may mean that the parameter is appropriately set so that the magnitude of the magnetic flux induced by the current in a specific frequency band is strong.

The second side 122A of the sensing transformer 120A is differentially connected to the input terminal of the amplifying unit 130A as shown in FIG. 2 in order to supply the first induced current to the amplifying unit 130A. I can. In addition, according to the configuration of the amplifying unit 130A, the second side 122A of the sensing transformer 120A is a path connecting the input terminal of the amplifying unit 130A and the reference potential (reference potential 2) of the amplifying unit 130A. It can also be placed on top.

Meanwhile, as described above, the sensing unit 120 is implemented as the sensing transformer 120A as an example, and the spirit of the present invention is not limited thereto. Accordingly, a means capable of sensing only the first currents I11 and I12 input in the common mode on the high current paths 111A and 112A may be used as the sensing unit 120 without limitation.

However, this is an example and the spirit of the present invention is not limited thereto. That is, the number of windings of the high current paths 111A and 112A and the secondary side 122A windings around the core 123A may be appropriately determined according to the requirements of the system in which the current compensation device 100A is used.

According to an embodiment of the present invention, the sensing transformer 120A may include a core having a through opening and generating an output signal based on a magnetic flux density generated by a first current on at least two high current paths. . At this time, the core has a clamp structure that can be opened and closed, and at least two or more high current paths 111A and 112A may each be inserted in the open state.

4A and 4B are views for explaining a sensing transformer 120A including a core 123A having a clamp structure that can be opened and closed.

Referring to FIG. 4A, the sensing unit 120 may be implemented as a sensing transformer 120A including a core 123A having a clamp structure. Large current paths 111A and 112A may be inserted into the opening of the sensing transformer 120A as shown.

Hereinafter, it is assumed that the high current paths 111A and 112A and the secondary side 122A windings are inserted (or wound) in the core 123A of the sensing transformer 120A in consideration of the direction of generation of the magnetic flux and/or the magnetic flux density. Explained as.

As the first current I11 is input to the high current path 111A, a magnetic flux density B11 may be induced in the core 123A. Similarly, as the first current I12 is input to the high current path 112A, the magnetic flux density B12 may be induced in the core 123A. The first induced current ID1 may be induced in the winding of the second secondary side 122A by the induced magnetic flux densities B11 and B12.

In this way, the sensing transformer 120A is configured so that the first magnetic flux densities B11 and B12 induced by the first currents I11 and I12 can overlap each other (or reinforce each other), so that two or more high current paths A first induced current ID1 corresponding to the first currents I11 and I12 may be generated at the second secondary side 122A insulated from the 111A and 112A.

Meanwhile, the sensing transformer 120A may be configured such that the second magnetic flux density induced by the second currents I21 and I22 flowing through each of the two or more large current paths 111A and 112A satisfies a predetermined magnetic flux density condition.

4B is a case in which the high current paths 111A and 112A are wound once on the primary side 121A of the sensing transformer 120A of the present invention, the second currents I21 and I22 are induced to the sensing transformer 120A. It is a figure for demonstrating the 2nd magnetic flux density (B21, B22) which becomes.

Referring to FIG. 4B, the sensing unit 120 may be implemented as a sensing transformer 120A including a core 123A having a clamp structure. As in FIG. 4A, as shown in the opening of the sensing transformer 120A, high current paths 111A and 112A may be inserted.

As in FIG. 3B, the sensing transformer 120A has a second induced current ID2 induced by the second current I21 and I22 flowing in each of two or more high current paths 111A and 112A. It can be configured to satisfy. In this case, the predetermined second induced current condition may be a condition in which the magnitude of the second induced current ID2 is less than a predetermined threshold magnitude.

In this way, the sensing transformer 120A is configured so that the second magnetic flux densities B21 and B22 induced by the second currents I21 and I22 cancel each other, so that only the first currents I11 and I12 are sensed. I can.

However, this is an example and the spirit of the present invention is not limited thereto.

In the sensing transformer 120A according to an embodiment of the present invention, both the high current paths 111A and 112A and the winding of the second secondary side 122A may be inserted into the core 123A. In this case, the sensing transformer 120A may be configured such that the high current paths 111A and 112A and the windings of the secondary side 122A only pass through the opening of the core 123A.

According to the embodiment of the present invention disclosed in FIGS. 4A and 4B, the core 123A may have a clamp structure in which a part of the core 123A can be opened or closed in order to pass or insert the high current paths 111A and 112A into the central opening.

The clamp-type core 123A of the present invention may be configured so that the high current paths 111A and 112A can pass through the central through opening in an open state, and after the high current paths 111A and 112A are inserted, the core 123A The open part of) can be closed. However, this is only an example, and the core 123A may be implemented in various shapes in which the large current paths 111A and 112A can be inserted into the through opening. For example, the core 123A may be implemented in a shape of a rectangle in addition to a circular shape as shown in FIGS. 4A and 4B.

As described above, the present invention is configured to simply insert (or simply pass) the high current paths 111A and 112A into the core 123A, and the sensing unit 120 winds the high current paths 111A and 112A several times around the core 123A. Compared to, its size can be drastically reduced.

In particular, in a high power/high current system, since a material that is not easy to process such as a thick copper conductor is used as the high current paths 111A and 112A, the high current paths 111A and 112A are simply inserted into the core 123A, Productivity and assembly properties using high power/high current systems can be improved.

The amplifying unit 130A may amplify the output signal output from the above-described sensing unit 120 to generate an amplified output signal.

In one embodiment, the amplifying unit 130 may be implemented as an amplifying unit 130A that amplifies the first induced current generated by the sensing transformer 120A to generate an amplified current.

In the present invention,'amplification' by the amplifying unit 130 may mean adjusting the size and/or phase of the amplification target. For example, the amplifying unit 130A may generate an amplified current by changing the phase of the first induced current by 180 degrees and increasing the magnitude by K times (K>=1).

By the amplification of the amplifying unit 130A as described above, the current compensation device 100A generates compensation currents IC1 and IC2 having the same magnitude as the first currents I11 and I12 and opposite to the phase, thereby generating a large current path 111A. , 112A) may compensate for the first currents I11 and I12.

The amplification unit 130A may generate an amplified current in consideration of the transformation ratio of the above-described sensing transformer 120A and the transformation ratio of the compensation unit 140 to be described later. That is, the amplification unit 130A may determine the current amplification according to the transformation ratio of the sensing transformer 120A included in the sensing unit 120 and the current amplification according to the transformation ratio of the compensation transformer 140A included in the compensation unit 140. The amplification degree can be set on the basis.

Specifically, the sensing transformer 120A converts the first currents I11 and I12 having a size of 1 into a first induced current having a size of 1/F1, and the compensation unit 140 converts the amplified current having a size of 1. When implemented as a compensation transformer 140A that converts a compensation current of 1/F2, the amplification unit 130A considers the current amplification degree of the sensing transformer 120A and the current amplification degree of the compensation transformer 140A. It can generate an amplification current that is F1xF2 times. In this case, the amplifying unit 130A may generate an amplified current such that the phase of the amplified current is opposite to the phase of the first induced current.

The amplification unit 130A may be implemented by various means. For example, the amplification unit 130A may include an OP-AMP. Optionally, the amplifying unit 130A may include a plurality of passive elements such as a resistor and a capacitor in addition to the OP-AMP. In addition, the amplification unit 130A may include a Bipolar Junction Transistor (BJT). Optionally, the amplification unit 130A may include a plurality of passive elements and additional impedances in addition to the BJT. However, the above implementation method of the amplification unit 130A is exemplary, and the spirit of the present invention is not limited thereto, and the means for'amplification' described in the present invention is used without limitation as the amplification unit 130A of the present invention. I can.

5A and 5B are diagrams for explaining that the amplifying unit 130A according to an embodiment of the present invention is implemented with a bipolar junction transistor (BJT) and a plurality of passive elements.

Referring to FIG. 5A, the amplifying unit 130A may include a first amplifying device for amplifying a positive signal and a second amplifying device for amplifying a negative signal. For example, the amplifying unit 130A may be implemented as a push-pull amplifier using an amplifying element including an npn type BJT and a pnp type BJT.

Specifically, in the case of a positive swing in which a voltage due to noise is greater than 0, an amplifying element including an npn-type BJT may operate. At this time, the operating current may flow through the npn-type BJT path. In the case of a negative swing in which the voltage due to noise is less than 0, an amplifying element including a pnp type BJT can operate. At this time, the operating current can flow through the pnp type BJT path.

The push-pull amplifier of the amplification unit 130A is a capacitor (C _e ) at the emitter stage of each of the npn-type BJT, pnp-type BJT, and BJT, the capacitor (C _b ) at the base stage of each BJT, Resistors (R _npn , R _pnp ) of the collector end of each BJT, resistance of the emitter end of two BJTs (R _e ), and resistance of the base end of two BJTs (R _bb ) may be included.

The first end of the capacitor C _e of the emitter end of each of the two BJTs is connected to the secondary side 122A of the sensing transformer 120A, and the second end is the emitter of each BJT. It may be connected to the stage.

Each BJT's collector end resistance (R _npn , R _pnp ), two BJT's emitter end's resistance (R _e ), and two BJT's base end's resistance (R _bb ) are each BJT's DC operation It may be a configuration for designing a point.

Push-pull amplifier of the amplifier unit (130A) may further comprise a further C _DC, C _DC may be a decoupling (decoupling) capacitors for V _DC voltage from the third device (400), npn type BJT , It is connected to the collector of the pnp type BJT so that only the AC signal can be selectively coupled (coupling).

According to an embodiment of the present invention, the push-pull amplifier may be implemented as a feedback system for inputting an amplified signal or amplified current back to the base of the BJT included in the amplifying element.

Specifically, the amplified current generated by the amplifying unit 130A induces a compensation current to the secondary side 142A based on the third magnetic flux density, and then passes through the primary side 141A of the compensation transformer 140A. It may be input to the second side 122A of the sensing transformer 120A. That is, as the amplified current is fed back to the secondary side 122A of the sensing transformer 120A, the push-pull amplifier can stably obtain a constant current gain for the active EMI filter operation.

5B is a simplified diagram of the amplifier of FIG. 5A.

5B, the induced current I _i generated in the secondary side 122A of the sensing transformer 120A may be a first induced current input to the amplifying unit 130A or an output signal including a first induced current. have. In addition, I have _OBJT I _OBJT through a first side (141A) of the compensation transformer (140A) may be an output current amplified or amplified by the amplifier unit (130A).

β is the current gain of the BJT device itself, and I _i is expressed as a function of I _OBJT as shown in Equation 1.

Accordingly, the amplification degree A _i,amp of the amplifying unit 130A can be expressed as in Equation 2.

Since the current gain β of the BJT has a value much larger than 1 (β>>1), A _i,amp can be approximated to -1.

Accordingly, the current compensating device 100A is designed to satisfy N _sen N _inj = 1, so that the noise current can be canceled with the compensation current. In this case, N _SEN may be the number of windings ratio or transformation ratio of the sensing transformer 120A, and N _INJ may be the number of windings ratio or transformation ratio of the compensation transformer 140A.

The amplifier of this embodiment can obtain a more stable current gain by returning the output current back to the input to form a feedback system.

6A and 6B are diagrams for explaining an amplifying unit 130A according to another embodiment of the present invention.

Referring to FIG. 6A compared to FIG. 5A, the amplification unit 130A according to another embodiment of the present invention includes, in addition to the above-described first and second amplifying elements, amplification ratios of the first and second amplifying elements. It may include at least one impedance (Z1, Z2) to control.

For example, the amplification unit 130A is a capacitor (C _e ) at the emitter stage of each of npn-type BJT, pnp-type BJT, and BJT, and a capacitor (C _b ) at the base stage of each BJT, and BJT. It may include the resistance of the collector end of (R _npn , R _pnp ), the resistance of the emitter end of two BJTs (R _e ), and the resistance of the base end of two BJTs (R _bb ). The first end of the capacitor C _e of the emitter end of each of the two BJTs is connected to the secondary side 122A of the sensing transformer 120A, and the second end is the emitter of each BJT. It may be connected to the stage. Each BJT's collector end resistance (R _npn , R _pnp ), two BJT's emitter end's resistance (R _e ), and two BJT's base end's resistance (Rbb) are each BJT's DC operating point It may be a configuration for designing.

In contrast to the amplification unit 130A described in FIG. 5A, the amplifier of FIG. 6A may include at least one impedance Z1 and Z2 for controlling an amplification ratio of the first amplifying element and the second amplifying element. The first impedance Z1 and the second impedance Z2 may be implemented using a combination of one or more resistor (R) elements, capacitor (C) elements, or inductor (L) elements, respectively.

For example, the first impedance Z1 and the second impedance Z2 may be implemented in RC series or RLC series, respectively, and may be designed to more precisely compensate the phase and magnitude of current compensation according to frequency.

The first end of the first impedance Z1 may be connected to the first secondary side 141A of the compensation transformer 140A, and the second end may be connected to the emitter end of each of the two BJTs. In addition, the first terminal of the second impedance may be connected to the primary side 141A of the compensation transformer 140A, and the second terminal may be connected to the capacitor C _b of the base terminal of each BJT. have.

The amplification degree A _iamp of the amplifying unit 130A according to another embodiment of the present invention may be adjusted according to the above-described at least one impedance value Z1 and Z2. For example, when the first impedance Z1 is R ₁ and the second impedance Z2 is (n-1) R ₁ , the amplification degree A _iamp may be designed as -n (n>1). . At this time, the design value of n can be tuned in consideration of the characteristic error of the device.

6B is a simplified diagram of the amplifier of FIG. 6A.

Referring to FIG. 6B, the first induced current I _i generated in the second secondary side 122A of the sensing transformer 120A may be an input current input to the amplifying unit 130A. In addition, I _OBJT may be an amplified current I _OBJT passing through the primary side 141A of the compensation transformer 140A is an output current output from the amplifying unit 130A.

The amplification degree A _i,amp of the amplification unit 130A can be expressed as in Equation 3.

(β>>1, Z2 >> rπ/β, Z1 = R _1, Z2 = (n-1) Z-1)

As shown in Equation 3, the amplifier of the present invention may be designed with a current amplification degree (Ai,amp) = -n (n>1). According to the above example, the amplification degree (Ai,amp) can be designed as Nsen*Ninj, and precise tuning of the current amplification degree can be possible by setting the above Z1 and Z2 in consideration of the error.

In particular, when the current compensating device includes the sensing unit 120A having the clamp structure described in FIGS. 4A to 4B, the sensing gain of the first current is not large, and thus at least one impedance Z1 and Z2 is appropriately adjusted to the sensing unit ( 120A) can compensate for the decrease in gain.

Meanwhile, as described above, the amplifying unit 130A may receive power from the third device 400A and amplify the first induced current to generate an amplified current.

The compensation unit 140 may generate a compensation current based on the output signal amplified by the amplification unit 130 described above.

In one embodiment, the compensation unit 140 may include a compensation transformer 140A. At this time, the compensation transformer 140A is insulated from the above-described large current paths 111A and 112A, and compensates on the side of the large current paths 111A and 112A (or to the secondary side 142A to be described later) based on the amplified current. It may be a means for generating an electric current.

More specifically, the compensation transformer 140A is applied to the third magnetic flux density induced by the amplified current generated by the amplifying unit 130A on the primary side 141A differentially connected to the output terminal of the amplifying unit 130A. Based on the compensation current may be generated in the second secondary side 142A. In this case, the second secondary side 142A may be disposed on a path connecting the compensation capacitor unit 150A to be described later and the reference potential (reference potential 1) of the current compensation device.

On the other hand, the primary side (141A) of the compensation transformer (140A), the amplification unit (130A), and the secondary side (122A) of the sensing transformer (120A) are separated from the remaining components of the current compensation device (100A). It can be connected to the reference potential (reference potential 2).

As described above, the present invention uses a reference potential different from the remaining components for the component generating the compensation current, and by using a separate power source, the component generating the compensation current can operate in an insulated state. It is possible to improve the reliability of the current compensating device 100A.

In one embodiment, the compensation capacitor unit 150 is a compensation capacitor unit 150A providing a path through which the current generated by the compensation transformer 140A flows through each of the two high current paths 111A and 112A as described above. Can be implemented.

7 is a diagram for explaining the currents IL1 and IL2 flowing through the compensation capacitor unit 150A.

The compensation capacitor unit 150A may be configured such that the current IL1 flowing between the two large current paths 111A and 112A through the compensation capacitor satisfies a predetermined first current condition. In this case, the predetermined first current condition may be a condition in which the magnitude of the current IL1 is less than a predetermined first threshold magnitude.

In addition, the compensation capacitor unit 150A has a current Il2 flowing between each of the two large current paths 111A and 112A and the reference potential (reference potential 1) of the current compensation device 100A through the compensation capacitor. It can be configured to satisfy the condition. In this case, the predetermined second current condition may be a condition in which the magnitude of the current IL2 is less than the predetermined second threshold magnitude.

The compensation current flowing in each of the two large current paths 111A and 112A along the compensation capacitor unit 150A cancels the first currents I11 and I22 on the large current paths 111A and 112A, thereby canceling the first currents I11 and I22. ) Can be prevented from being transmitted to the second device 200A. In this case, the first currents I11 and I22 and the compensation current may be currents having the same magnitude and opposite phases.

Accordingly, the current compensating device 100A according to an embodiment of the present invention applies the first currents I11 and I12 input in a common mode to each of the two high current paths 111A and 112A connected to the first device 300A. By actively compensating, it is possible to prevent malfunction or damage of the second device 200A.

8 is a diagram schematically showing a configuration of a current compensation device 100B according to another embodiment of the present invention. Hereinafter, descriptions of contents overlapping with those described with reference to FIGS. 1 to 7 will be omitted.

The current compensation device 100B according to another embodiment of the present invention includes first currents I11, I12, and I13 input in a common mode to each of the high current paths 111B, 112B, and 113B connected to the first device 300B. ) Can be actively compensated.

To this end, the current compensation device 100B according to another embodiment of the present invention includes three large current paths 111B, 112B, and 113B, a sensing transformer 120B, an amplifying unit 130B, a compensation transformer 140B, and a compensation capacitor. It may include a part 150B.

Looking in comparison with the current compensating device 100A according to the embodiment described in FIGS. 2 to 7, the current compensating device 100B according to the embodiment illustrated in FIG. 8 includes three large current paths 111B, 112B, and 113B. And, accordingly, there is a difference between the sensing transformer 120B and the compensation capacitor unit 150B. Therefore, hereinafter, the current compensation device 100B will be described based on the above-described differences.

The current compensation device 100B according to another embodiment of the present invention may include a first large current path 111B, a second large current path 112B, and a third large current path 113B, which are separated from each other. According to an embodiment, the first large current path 111B may be an R-phase, the second large current path 112B may be an S-phase, and the third large current path 113B may be a T-phase power line. The first currents I11, I12, and I13 may be input to each of the first high current path 111B, the second high current path 112B, and the third high current path 113B in a common mode.

The first side 121B of the sensing transformer 120B according to another embodiment of the present invention is disposed in each of the first high current path 111B, the second high current path 112B, and the third high current path 113B. It is possible to generate a first induced current. Magnetic flux densities generated in the sensing transformer 120B by the first currents I11, I12, and I13 on the three high current paths 111B, 112B, and 113B may be reinforced with each other. The process of generating the first induced current by the first currents I11, I12, and I13 has been described in FIG. 3A, and thus a detailed description thereof will be omitted.

On the other hand, when the current compensating device 100B includes three high current paths 111B, 112B, and 113B as shown in FIG. 8, when the clamp type sensing unit as shown in FIGS. 4A and 4B is used, sensing is performed compared to when using a conventional sensing transformer. It is possible to maximize the effect of reducing the size of the sub-size and the size of the current compensating device 100B.

Meanwhile, in the compensation capacitor unit 150B according to another embodiment of the present invention, the compensation currents IC1, IC2, and IC3 generated by the compensation transformer are applied to the first high current path 111B, the second high current path 112B, and A path flowing through each of the third large current paths 113B may be provided.

The current compensating device 100B according to this embodiment may be used to cancel (or block) the first currents I11, I12, and I13 that move from the load of the three-phase three-wire power system to the power source.

9 is a diagram schematically showing the configuration of a current compensating device 100C according to another embodiment of the present invention. Hereinafter, descriptions of contents overlapping with those described with reference to FIGS. 1 to 8 will be omitted.

The current compensating device 100C according to the embodiment includes first currents I11, I12, I13, I14 input in a common mode to each of the high current paths 111C, 112C, 113C, and 114C connected to the first device 300C. Can be actively compensated for.

To this end, the current compensation device 100C according to the embodiment includes four large current paths 111C, 112C, 113C, and 114C, a sensing transformer 120C, an amplification unit 130C, a compensation transformer 140C, and a compensation capacitor unit 150C. ) Can be included.

Looking at the current compensating device 100A according to the embodiment described in FIGS. 2 to 7 and the current compensating device 100B according to the embodiment described in FIG. 5, the current compensating device according to the embodiment shown in FIG. 9 ( 100C) includes four large current paths 111C, 112C, 113C, and 114C, and accordingly, there is a difference between the sensing transformer 120C and the compensation capacitor unit 150C. Therefore, hereinafter, the current compensation device 100C will be described centering on the above-described differences.

First, the current compensation device 100C according to the embodiment includes a first high current path 111C, a second high current path 112C, a third high current path 113C, and a fourth high current path 114C. I can. According to an embodiment, the first large current path 111C is an R phase, the second large current path 112C is an S phase, the third large current path 113C is a T phase, and the fourth large current path 114C is It may be an N-phase power line. The first currents I11, I12, I13, and I14 are the first high current path 111C, the second high current path 112C, the third high current path 113C, and the fourth high current path 114C. ) Can be input in common mode.

The first side 121C of the sensing transformer 120C according to the embodiment includes a first large current path 111C, a second large current path 112C, a third large current path 113C, and a fourth large current path 114C, respectively. And may generate a first induced current. The magnetic flux densities generated in the sensing transformer 120C by the first currents I11, I12, I13, and I14 on the four large current paths 111C, 112C, 113C, and 114C may be reinforced with each other. The process of generating the first induced current by the first currents I11, I12, I13, and I14 has been described in FIG. 4A, and thus a detailed description thereof will be omitted.

Meanwhile, in the compensation capacitor unit 150C according to the embodiment, the compensation currents IC1, IC2, IC3, and IC4 generated by the compensation transformer are applied to the first high current path 111C, the second high current path 112C, and the third high current. A path flowing through the path 113C and the fourth large current path 114C may be provided.

The current compensation device 100C according to this embodiment may be used to cancel (or block) the first current (I11, I12, I13, I14) moving from the load of the three-phase, four-wire power system to the power source. have.

Even in this case, when the clamp-type sensing unit as shown in FIGS. 4A and 4B is used, the effect of reducing the size of the sensing unit and the size of the current compensating device 100C can be further maximized compared to when using a conventional sensing transformer.

10 is a diagram schematically showing the configuration of a system in which the current compensation device 100B according to the embodiment shown in FIG. 8 is used.

The current compensation device 100B according to the embodiment may be used with one or more other compensation devices 500 on a high current path connecting the second device 200B and the first device 300B.

For example, the current compensating device 100B according to the embodiment may be used together with the compensating device 1 510 that compensates for a first current input in a common mode. In this case, the compensation device 1 510 may be implemented as an active element, similar to the compensation device 100B, or may be implemented only as a passive element.

In addition, the current compensating device 100B according to the embodiment may be used together with the compensating device 2 520 for compensating a third current input in a differential mode. In this case, the compensation device 2 520 may also be implemented as an active element or only a passive element.

Also, the current compensating device 100B according to the embodiment may be used together with the compensating device n 530 for compensating voltage. In this case, the compensation device n 530 may also be implemented as an active element or only a passive element.

Meanwhile, the type, quantity, and arrangement order of the compensation device 500 described in FIG. 10 are exemplary, and the spirit of the present invention is not limited thereto. Therefore, various quantities and types of compensation devices may be further included in the system according to the design of the system. In addition, optionally, the embodiment illustrated in FIG. 10 may be equally applied to all other embodiments of the present specification.

The specific implementations described in the present invention are examples and do not limit the scope of the present invention in any way. For brevity of the specification, descriptions of conventional electronic configurations, control systems, software, and other functional aspects of the systems may be omitted. In addition, the connection or connection members of the lines between the components shown in the drawings exemplarily represent functional connections and/or physical or circuit connections. Connections, or circuit connections, may be represented. In addition, if there is no specific mention such as "essential", "important", etc., it may not be an essential component for the application of the present invention.

Therefore, the spirit of the present invention is limited to the above-described embodiments and should not be defined, and not only the claims to be described later, but also all ranges equivalent to or equivalently changed from the claims are within the scope of the spirit of the present invention. I would say.

100: current compensation device
111, 112: high current path
120: sensing unit
130: amplification unit
140: compensation unit
150: compensation capacitor unit
200: second device
300: first device

Claims (4)

A current compensating device for actively compensating for a first current input in a common mode to each of at least two or more large current paths connected to the first device,
At least two or more high current paths for passing a second current supplied by a second device to the first device;
A sensing unit having a through opening, the at least two large current paths being inserted into the through opening, sensing the first current on the at least two large current paths, and generating an output signal corresponding to the first current;
An amplification unit for amplifying the output signal to generate an amplified signal;
A compensation unit that generates a compensation current based on the amplified signal; And
Compensation capacitor unit for providing a path through which the compensation current flows through each of the at least two large current paths; Including,
The sensing unit includes a core having the through opening and generating the output signal based on the magnetic flux density generated by the first current on the at least two or more high current paths,
The core has a clamp structure that can be opened and closed, and each of the at least two large current paths is wound once and passed through the current compensation device. The method of claim 1,
The amplification unit,
A first amplifying element for amplifying a positive signal;
A second amplifying element for amplifying a negative signal; And
At least one impedance for controlling an amplification ratio of the first amplifying element and the second amplifying element; including, a current compensation device. According to claim 2
Each of the first amplifying element and the second amplifying element includes a bipolar junction transistor (BJT),
The at least one impedance is
A first impedance Z1 connected to the emitter terminal of the BJT of the first amplifying element and the second amplifying element; And
Including; a second impedance (Z2) connected to the base terminal of the BJT of the first amplifying element and the second amplifying element,
The first impedance Z1 and the second impedance Z2 control an amplification ratio of the first and second amplifying elements based on current amplification degrees of the sensing unit and the compensating unit. The method of claim 3,
When the current amplification degree of the sensing unit is 1/F1, and the current amplification degree of the compensating unit is 1/F2, the first impedance Z1 and the second impedance Z2 are determined so that the current amplification degree of the amplification unit is F1*F2. A current compensation device for adjusting an amplification ratio of the first amplifying element and the second amplifying element.

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