KR102580432B1 - Active Current Compensation Device Including One-Chip Integrated Circuit - Google Patents

Abstract

The present invention relates to an active current compensation device that actively compensates for noise generated in a common mode in each of at least two large current paths, comprising: a sensing unit that generates an output signal corresponding to the common mode noise current in the large current path; It includes an amplification unit that amplifies an output signal to generate an amplification current, a compensation unit that generates a compensation current based on the amplification current, and flows the compensation current to each of the at least two high current paths, wherein the amplification unit is It includes an integrated circuit unit and a single-chip integrated circuit, wherein the single-chip integrated circuit contains an active element whose device characteristics vary depending on temperature changes, and wherein the single-chip integrated circuit allows the amplification unit to remain within a certain range even when the temperature changes. Provides an active current compensation device designed to maintain performance.

Description

Active Current Compensation Device Including One-Chip Integrated Circuit}

Embodiments of the present invention relate to an active current compensation device including a single-chip integrated circuit (one-chip IC), which actively compensates for noise input in common mode on two or more high current paths connected to the power system. It relates to a current compensation device.

In general, electrical devices such as home appliances, industrial electrical products, or electric vehicles emit noise while operating. For example, noise may be emitted through power lines due to the switching operation of power conversion devices within electronic devices. If this noise is left unattended, it is not only harmful to the human body but also causes malfunctions or failures in surrounding parts and other electronic devices. In this way, the electromagnetic interference that electronic devices cause to other devices is called EMI (Electromagnetic Interference), and among them, noise transmitted through wires and board wiring is called conducted emission (CE) noise.

In order to ensure that electronic devices operate without causing malfunctions in surrounding components and other devices, the amount of EMI noise emissions from all electronic products is strictly regulated. Therefore, most electronic products necessarily include a noise reduction device (e.g., EMI filter) that reduces EMI noise current in order to satisfy regulations on noise emissions. For example, in white appliances such as air conditioners, electric vehicles, aviation, and energy storage systems (ESS), EMI filters are essential. Conventional EMI filters use a common mode choke (CM choke) to reduce common mode (CM) noise among conducted emission (CE) noise. The common mode (CM) choke is a passive filter and serves to 'suppress' the common mode noise current.

Meanwhile, to maintain the noise reduction performance of the passive EMI filter in a high-power system, the size or number of common mode chokes must be increased. Therefore, in high-power products, the size and price of passive EMI filters increase significantly.

In order to overcome the limitations of passive EMI filters as described above, interest in active EMI filters has emerged. An active EMI filter can remove EMI noise by detecting EMI noise and generating a signal that cancels out the noise. An active EMI filter includes an active circuit (or amplification unit) that can generate an amplified signal from a detected noise signal.

The active EMI filter may include, for example, a Bipolar Junction Transistor (BJT). However, when current flows through the BJT and heat is generated, the current gain of the BJT increases (or the internal resistance of the BJT decreases). Then, positive feedback occurs in which heat is generated again according to the increased current. Due to this positive feedback, heat continues to increase, which may cause the BJT to be damaged or lose its original characteristics. This phenomenon is called thermal runaway phenomenon.

When constructing the amplification part of an active EMI filter using a BJT, this thermal runaway problem must be resolved.

The present invention was devised to overcome the above problems, and its purpose is to provide an active current compensation device including a single-chip integrated circuit (one-chip IC).

However, these tasks are illustrative and do not limit the scope of the present invention.

According to an embodiment of the present invention, an active current compensation device that actively compensates for noise occurring in a common mode in each of at least two large current paths includes a sensing device that generates an output signal corresponding to the common mode noise current on the large current path. wealth; an amplifier that amplifies the output signal to generate an amplification current; and a compensation unit that generates a compensation current based on the amplification current and causes the compensation current to flow through each of the at least two high current paths, wherein the amplification unit includes a non-integrated circuit unit and a single-chip integrated circuit. , the single-chip integrated circuit internalizes active elements whose device characteristics vary depending on temperature changes, and the single-chip integrated circuit may be designed so that the amplification unit maintains performance within a certain range despite temperature changes.

According to one embodiment, an npn BJT and a pnp BJT are internalized in the integrated circuit of the single chip, and a diode may be connected between the base node of the npn BJT and the base node of the pnp BJT.

According to one embodiment, a resistor may be connected between the emitter node of the npn BJT and the emitter node of the pnp BJT.

According to one embodiment, the diode may perform a function of reducing emitter current flowing through the resistor.

According to one embodiment, the diode and the resistor may adjust DC bias currents of the npn BJT and the pnp BJT.

According to one embodiment, the emitter current flowing through the resistor may be maintained within a predetermined range as the temperature changes.

Other aspects, features and advantages in addition to those described above will become apparent from the following drawings, claims and detailed description of the invention.

The active current compensation device according to the embodiments of the present invention as described above can reduce price, area, volume, weight, and heat generation compared to a passive filter composed of a CM choke in a high-power system.

Additionally, the active current compensation device according to embodiments of the present invention can prevent thermal runaway phenomenon. The active current compensation device according to embodiments of the present invention can maintain a constant current range across temperature changes by utilizing both positive and negative feedback regarding the temperature of the BJT.

In addition, in the active current compensation device according to embodiments of the present invention, elements with temperature characteristics are formed in a single-chip integrated circuit (one-chip IC) and share temperature, so it is difficult to predict the characteristics of the elements according to temperature. It can be easy.

Therefore, it is possible to design an active circuit (or amplification unit) that is controllable and predictable despite temperature changes.

Since the amplifier according to embodiments of the present invention includes a single chip integrated circuit, current-voltage (I-V) characteristics can be designed to be controllable compared to the case where it is composed of commercially available discrete elements. That is, single chip integrated circuits according to embodiments of the present invention can be custom designed. That is, the current and voltage inside a single chip integrated circuit can be controlled.

In addition, the single-chip integrated circuit and the active current compensation device including the same according to embodiments of the present invention may have a slight increase in production cost even when mass-produced. Additionally, the size increase due to an increase in the number of semiconductor devices may be minimal.

Of course, the scope of the present invention is not limited by this effect.

Figure 1 schematically shows the configuration of a system including an active current compensation device 100 according to an embodiment of the present invention.
Figure 2 shows a more specific example of the embodiment shown in Figure 1, and schematically shows an active current compensation device (100A) according to an embodiment of the present invention.
FIG. 3 shows a more specific example of the embodiment shown in FIG. 2 and schematically shows an active current compensation device 100A-1 according to an embodiment of the present invention.
Figure 4 schematically shows a single-chip integrated circuit (one-chip IC) 131A according to one embodiment of the present invention.
FIG. 5 shows simulation results of bias voltage and current according to temperature of the single chip integrated circuit 131A shown in FIG. 4.
Figure 6 schematically shows the configuration of an active current compensation device 100A-2 according to another embodiment of the present invention.

Since the present invention can be modified in various ways and can have various embodiments, specific embodiments will be illustrated in the drawings and described in detail in the detailed description. The effects and features of the present invention and methods for achieving them will become clear by referring to the embodiments described in detail below along 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. When describing with reference to the drawings, identical or corresponding components will be assigned the same reference numerals and redundant description thereof will be omitted. .

In the following embodiments, terms such as first and second are used not in a limiting sense but for the purpose of distinguishing one component from another component. In the following examples, singular terms include plural terms unless the context clearly dictates otherwise. In the following embodiments, terms such as include or have mean that the features or components described in the specification exist, and do not exclude in advance the possibility of adding one or more other features or components. In the drawings, the sizes of components may be exaggerated or reduced for convenience of explanation. In the following embodiments, when components, parts, units, modules, etc. are connected, not only are the components, parts, units, and modules directly connected, but also other components are inserted between the components, parts, units, and modules. , also includes cases where parts, units, and modules are indirectly connected.

Figure 1 schematically shows the configuration of a system including an active current compensation device 100 according to an embodiment of the present invention. The active current compensation device 100 compensates for the first currents I11 and I12 (e.g., EMI) input in common mode (CM) from the first device 300 through two or more large current paths 111 and 112. noise current) can be actively compensated.

Referring to FIG. 1, the active current compensation device 100 may include a sensing unit 120, an amplifying unit 130, and a compensating unit 160.

In this specification, the first device 300 may be various types of power systems that use power supplied by the second device 200. For example, the first device 300 may be a load driven using power supplied by the second device 200. Additionally, the first device 300 stores energy using power supplied by the second device 200, and may be a load (eg, an electric vehicle) driven using the stored energy. However, it is not limited to this.

In this specification, the second device 200 may be a system of various types for supplying power to the first device 300 in the form of current and/or voltage. The second device 200 may be a device that supplies stored energy. However, it is not limited to this.

A power conversion device may be located on the first device 300 side. For example, the first currents I11 and I12 may be input to the current compensation device 100 through a switching operation of the power conversion device. That is, the first device 300 side can correspond to the noise source, and the second device 200 side can correspond to the noise receiver.

The two or more large current paths 111 and 112 may be paths for transmitting the power supplied by the second device 200, that is, the second currents I21 and I22, to the first device 300, for example, they may be power lines. there is. For example, each of the two or more high current paths 111 and 112 may be a live line and a neutral line. At least a portion of the large current paths 111 and 112 may pass through the current compensation device 100. The second currents I21 and I22 may be alternating currents having a frequency in the second frequency band. The second frequency band may be, for example, a 50Hz to 60Hz band.

Additionally, the two or more large current paths 111 and 112 may be paths through which noise generated in the first device 300, that is, the first currents I11 and I12, is transmitted to the second device 200. The first currents I11 and I12 may be input in common mode to each of the two or more large current paths 111 and 112. 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 virtual capacitance between the first device 300 and the surrounding environment. Alternatively, the first currents I11 and I12 may be noise currents generated by a switching operation of the power conversion device of the first device 300. The first currents I11 and I12 may be currents having a frequency in the first frequency band. The first frequency band may be a higher frequency band than the above-described second frequency band. The first frequency band may be, for example, a 150KHz to 30MHz band.

Meanwhile, the two or more large current paths 111 and 112 may include two paths as shown in FIG. 1, or may include three paths as shown in FIG. 6. In addition, the two or more high current paths 111 and 112 may include four paths. The number of high current paths 111 and 112 may vary depending on the type and/or type of power source used by the first device 300 and/or the second device 200.

The sensing unit 120 may detect the first currents I11 and I12 on the two or more large current paths 111 and 112 and generate output signals corresponding to the first currents I11 and I12. In other words, the sensing unit 120 may mean a means for detecting the first currents I11 and I12 on the large current paths 111 and 112. At least a portion of the large current paths 111 and 112 may pass through the sensing unit 120 for sensing the first currents I11 and I12, but an output signal is generated by sensing within the sensing unit 120. The portion may be insulated from the high current paths 111 and 112. For example, the sensing unit 120 may be implemented as a sensing transformer. The sensing transformer may sense the first currents I11 and I12 on the large current paths 111 and 112 while being insulated from the large current paths 111 and 112. However, the sensing unit 120 is not limited to a sensing transformer.

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

The amplification unit 130 is electrically connected to the sensing unit 120 and can amplify the output signal output by the sensing unit 120 to generate an amplified output signal. In the present invention, 'amplification' by the amplification unit 130 may mean adjusting the size and/or phase of the amplification target. The amplification unit 130 may be implemented by various means and may include active elements. In one embodiment, the amplifier 130 may include a Bipolar Junction Transistor (BJT). For example, the amplifier 130 may include a plurality of passive elements such as resistors and capacitors in addition to the BJT. However, it is not limited to this, and the means for 'amplification' described in the present invention can be used without limitation as the amplification unit 130 of the present invention.

According to one embodiment, the second reference potential 602 of the amplification unit 130 and the first reference potential 601 of the current compensation device 100 may be distinguished from each other. For example, when the amplification unit 130 is insulated from the large current paths 111 and 112, the second reference potential 602 of the amplification unit 130 and the first reference potential 601 of the current compensation device 100 can be distinguished from each other.

However, the present invention is not limited to this. For example, if the amplification unit 130 is not insulated from the high current paths 111 and 112, the reference potential of the amplification unit and the reference potential of the current compensation device may not be distinguished.

The amplifier 130 according to various embodiments of the present invention may include a single-chip integrated circuit 131 and a non-integrated circuit unit 132. A single-chip integrated circuit (one-chip IC) 131 may include the essential components of the active current compensation device 100. Essential components may include active elements. That is, the active elements included in the amplification unit 130 may be integrated into a single chip integrated circuit 131. The non-integrated circuit unit 132 of the amplifier unit 130 may not include active elements. The integrated circuit 131 may further include passive elements as well as active elements.

The integrated circuit 131 according to an embodiment of the present invention may physically be one IC chip. The integrated circuit 131 according to an embodiment of the present invention can be applied to the active current compensation device 100 of various designs. The single chip integrated circuit 131 according to an embodiment of the present invention has versatility as an independent module and can be applied to the current compensation device 100 of various designs.

The non-integrated circuit unit 132 according to an embodiment of the present invention may be modified depending on the design of the active current compensation device 100.

The single-chip integrated circuit (one-chip IC) 131 may include terminals b1, b2, e1, and e2 for connection to the non-integrated circuit unit 132. The integrated circuit 131 and the non-integrated circuit unit 132 can be combined together to function as an amplification unit 130. The combination of the integrated circuit 131 and the non-integrated circuit unit 132 can perform the function of generating an amplified signal from the output signal output from the sensing unit 120. The amplified signal may be input to the compensation unit 160.

Examples of the detailed configuration of the amplification unit 130 including the integrated circuit 131 and the non-integrated circuit unit 132 will be described later with reference to FIGS. 3, 5, and 6.

The amplifier 130 may receive power from a power supply 400 that is separate from the first device 300 and/or the second device 200. The amplifying unit 130 may receive power from the power supply 400 and amplify the output signal output from the sensing unit 120 to generate an amplified current.

The power supply device 400 may be a device that receives power from a power source unrelated to the first device 300 and the second device 200 and generates input power to the amplifier 130. Optionally, the power supply device 400 may be a device that receives power from any one of the first device 300 and the second device 200 to generate input power for the amplifier 130.

The single-chip integrated circuit (one-chip IC) 131 includes a terminal (c1) for connection to the power supply 400, a terminal (c2) for connection to the second reference potential 602, and a non-integrated circuit unit (132). ) may include terminals (b1, b2, e1, e2) to be connected to. In another embodiment, the single chip integrated circuit 131 may further include terminals for other functions.

The power supply device 400 may supply a direct current (DC) voltage V _dc based on the second reference potential 602 to drive the amplifier 130. A decoupling capacitor C _dc for V _dc may be connected in parallel to the power supply 400. Capacitor C _dc is connected to the outside of the integrated circuit 131, and may be connected between the power terminal (c1) and the terminal (c2) corresponding to the second reference potential.

The remaining components of the amplifier unit 130 except the integrated circuit 131 may be included in the non-integrated circuit unit 132. Therefore, it may be said that the capacitor C _dc is included in the non-integrated circuit unit 132.

The compensation unit 160 may generate compensation currents IC1 and IC2 based on the output signal amplified by the amplifier 130. The output side of the compensation unit 160 may be connected to the high current paths 111 and 112 to flow compensation currents IC1 and IC2 to the high current paths 111 and 112.

According to one embodiment, the output side of the compensation unit 160 may be insulated from the amplification unit 130. For example, the compensation unit 160 may include a compensation transformer for the insulation. For example, the output signal of the amplifier 130 may flow through the primary side of the compensation transformer, and a compensation current based on the output signal may be generated on the secondary side of the compensation transformer.

However, the present invention is not limited to this. According to another embodiment, the output side of the compensation unit 160 may be non-insulated from the amplification unit 130. In this case, the amplification unit 130 may be non-insulated from the high current paths 111 and 112.

The compensation unit 160 injects compensation currents (IC1, IC2) into the large current paths (111, 112) through each of two or more large current paths (111, 112) in order to offset the first currents (I11, I12). ) can be done. The compensation currents IC1 and IC2 may have the same magnitude and opposite phases as the first currents I11 and I12.

Figure 2 shows a more specific example of the embodiment shown in Figure 1, and schematically shows an active current compensation device (100A) according to an embodiment of the present invention. The active current compensation device 100A actively compensates for the first currents I11 and I12 (e.g., noise current) input in common mode to each of the two large current paths 111 and 112 connected to the first device 300. Compensation is possible.

Referring to FIG. 2, the active current compensation device 100A may include a sensing transformer 120A, an amplifier 130, and a compensation unit 160A.

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 detecting the first currents I11 and I12 on the high current paths 111 and 112 while being insulated from the high current paths 111 and 112. The sensing transformer 120A may sense the first currents I11 and I12, which are noise currents input from the first device 300 to the high current paths 111 and 112 (eg, power lines).

The sensing transformer 120A may include a primary side 121A disposed on the high current paths 111 and 112, and a secondary side 122A differentially connected to the input terminal of the amplifier 130. there is. The sensing transformer 120A is 2 based on the magnetic flux density induced by the first currents I11 and I12 in the primary side 121A (e.g., primary winding) disposed on the high current paths 111 and 112. An induced current can be created on the primary side (122A) (e.g., secondary winding). The primary side 121A of the sensing transformer 120A may be, for example, a winding in which the first high current path 111 and the second high current path 112 are each wound around one core. However, the present invention is not limited to this, and the primary side 121A of the sensing transformer 120A may have a first high current path 111 and a second high current path 112 passing through the core.

Specifically, the magnetic flux density induced by the first current (I11) on the first large current path 111 (e.g., live line) and the first current (I12) on the second large current path 112 (e.g., neutral line) The magnetic flux densities induced by may be configured to overlap (or reinforce) each other. At this time, second currents (I21, I22) also flow on the large current paths (111, 112), and the magnetic flux density induced by the second current (I21) on the first large current path (111) and the second large current path (112) ) The magnetic flux densities induced by the first current (I22) may be configured to cancel each other out. Also, as an example, the sensing transformer 120A may have the magnitude of the magnetic flux density induced by the first currents I11 and I12 in the first frequency band (for example, a band ranging from 150 KHz to 30 MHz) at the second frequency. It may be configured to be larger than the magnitude of the magnetic flux density induced by the second currents I21 and I22 in the band (for example, a band ranging from 50 Hz to 60 Hz).

In this way, the sensing transformer 120A is configured so that the magnetic flux densities induced by the second currents I21 and I22 cancel each other, so that only the first currents I11 and I12 are sensed. That is, the current induced in the secondary side 122A of the sensing transformer 120A may be a current obtained by converting the first currents I11 and I12 at a certain ratio.

For example, in the sensing transformer 120A, the turns ratio of the primary side 121A and the secondary side 122A is 1:N _sen , and the self-inductance of the primary side 121A of the sensing transformer 120A is L. When _sen , the secondary side 122A may have a self-inductance of N _sen ² ·L _sen . At this time, the current induced in the secondary side (122A) is 1/N _sen times the first current (I11, I12). In one example, the primary side 121A and the secondary side 122A of the sensing transformer 120A may be coupled with a coupling coefficient of k _sen .

The secondary side 122A of the sensing transformer 120A may be connected to the input terminal of the amplifier 130. For example, the secondary side 122A of the sensing transformer 120A may be differentially connected to the input terminal of the amplifier 130 to provide an induced current or induced voltage to the amplifier 130.

The amplifier 130 may amplify the current detected by the sensing transformer 120A and induced in the secondary side 122A. For example, the amplifier 130 may amplify the magnitude of the induced current at a certain rate and/or adjust the phase.

According to various embodiments of the present invention, the amplification unit 130 may include a single-chip integrated circuit (one-chip IC) 131 and a non-integrated circuit unit 132 that is a component other than the single chip.

The integrated circuit 131 may include active elements. The integrated circuit 131 may be connected to the power supply 400 based on the second reference potential 602 to drive the active element. The second reference potential 602 can be distinguished from the first reference potential 601 of the current compensation device 100A (or compensation unit 160A).

The single chip integrated circuit 131 includes a terminal c1 for connection to the power supply 400, a terminal c2 for connection to the second reference potential 602, and a terminal for connection to the non-integrated circuit unit 132. (b1, b2, e1, e2) can be formed.

The compensation unit 160A may be an example of the compensation unit 160 described above. In one embodiment, the compensation unit 160A may include a compensation transformer 140A and a compensation capacitor unit 150A. The amplification current amplified by the above-described amplifier 130 may flow to the primary side 141A of the compensation transformer 140A.

The compensation transformer 140A according to an embodiment may be a means for insulating the amplification unit 130 including an active element from the high current paths 111 and 112. That is, the compensation transformer 140A is insulated from the large current paths 111 and 112, and generates a compensation current (on the secondary side 142A) for injection into the large current paths 111 and 112 based on the amplified current. It may be a means for

The compensation transformer 140A may include a primary side 141A differentially connected to the output terminal of the amplifier 130, and a secondary side 142A connected to the high current paths 111 and 112. there is. Compensation transformer 140A induces a compensation current in secondary side 142A (e.g., secondary winding) based on the magnetic flux density induced by the amplification current flowing in primary side 141A (e.g., primary winding). can do.

At this time, the secondary side 142A may be placed on a path connecting the compensation capacitor unit 150A, which will be described later, and the first reference potential 601 of the current compensation device 100A. That is, one end of the secondary side (142A) is connected to the high current path (111, 112) through the compensation capacitor unit (150A), and the other end of the secondary side (142A) is connected to the first end of the active current compensation device (100A). 1 Can be connected to the reference potential (601). Meanwhile, the primary side 141A of the compensation transformer 140A, the amplifier 130, and the secondary side 122A of the sensing transformer 120A are separated from the remaining components of the active current compensation device 100A. It may be connected to the second reference potential 602. The first reference potential 601 of the current compensation device 100A according to one embodiment and the second reference potential 602 of the amplification unit 130 may be distinguished.

As such, the current compensation device 100A according to one embodiment uses a different reference potential (i.e., the second reference potential 602) for the component that generates the compensation current from the remaining components, and uses a separate power supply ( By using 400), the components that generate the compensation current can be operated in an insulated state, thereby improving the reliability of the active current compensation device (100A). However, the active current compensation device including the integrated circuit 131 and the non-integrated circuit portion 132 according to the present invention is not limited to this insulating structure. The active current compensation device according to another embodiment of the present invention may be non-insulated from the high current path.

In the compensation transformer (140A) according to one embodiment, the turns ratio of the primary side (141A) and the secondary side (142A) is 1:N _inj , and the self-inductance of the primary side (141A) of the compensation transformer (140A) is Assuming L _inj , the secondary side 142A may have a self-inductance of N _inj ² ·L _inj . At this time, the current induced in the secondary side (142A) is 1/N _inj times the current (i.e., amplification current) flowing in the primary side (141A). In one example, the primary side 141A and the secondary side 142A of the compensation transformer 140A may be coupled with a coupling coefficient of k _inj .

The current converted through the compensation transformer 140A may be injected as compensation currents IC1 and IC2 into the high current paths 111 and 112 (eg, power lines) through the compensation capacitor unit 150A. Accordingly, the compensation currents IC1 and IC2 may have the same magnitude and opposite phase as the first currents I11 and I12 in order to cancel the first currents I11 and I12. Accordingly, the size of the current gain of the amplification unit 130 can be designed to be N _sen ·N _inj . However, since magnetic coupling loss may occur in actual situations, the target current gain of the amplifier 130 may be designed to be higher than N _sen ·N _inj .

As described above, the compensation capacitor unit 150A may provide a path through which the current generated by the compensation transformer 140A flows to each of the two large current paths 111 and 112.

The compensation capacitor unit 150A is a Y-capacitor (Y) whose one end is connected to the secondary side 142A of the compensation transformer 140A and the other end is connected to each of the large current paths 111 and 112. -cap) may be included. For example, one end of the two Y-caps shares a node connected to the secondary side (142A) of the compensation transformer (140A), and the opposite ends of each of the two Y-caps are connected to the first high current path 111 and the It may have a node connected to the second high current path 112.

The compensation capacitor unit 150A may flow compensation currents IC1 and IC2 induced by the compensation transformer 140A to the power line. The current compensation device 100A can reduce noise by the compensation currents IC1 and IC2 compensating (or offsetting) the first currents I11 and I12.

Meanwhile, the compensation capacitor unit 150A may be configured so that the current IL1 flowing between the two large current paths 111 and 112 through the compensation capacitor is less than the first threshold size. Additionally, the compensation capacitor unit 150A may be configured so that the current IL2 flowing between each of the two large current paths 111 and 112 and the first reference potential 601 through the compensation capacitor is less than the second threshold size.

The active current compensation device 100A according to an embodiment can realize an isolated structure by using a compensation transformer 140A and a sensing transformer 120A.

FIG. 3 shows a more specific example of the embodiment shown in FIG. 2 and schematically shows an active current compensation device 100A-1 according to an embodiment of the present invention. The active current compensation device 100A-1, the amplifier 130A, and the integrated circuit 131A shown in FIG. 3 are the active current compensation device 100A, the amplifier 130, and the integrated circuit shown in FIG. 2. These are examples of the circuit 131.

The active current compensation device 100A-1 according to one embodiment may include a sensing transformer 120A, an amplification unit 130A, a compensation transformer 140A, and a compensation capacitor unit 150A. In one embodiment, the active current compensation device 100A-1 may further include a decoupling capacitor portion 170A on the output side (i.e., the second device 200 side). In other embodiments, the decoupling capacitor unit 170A may be omitted. Descriptions of the sensing transformer 120A, compensation transformer 140A, and compensation capacitor unit 150A are omitted since they are redundant.

In one embodiment, the induced current induced in the secondary side (122A) by the sensing transformer (120A) may be differentially input to the amplifier (130A).

The amplification unit 130A of the active current compensation device 100A-1 according to an embodiment may include a single chip integrated circuit 131A and a non-integrated circuit unit. The remaining components of the amplifier unit 130A, excluding the integrated circuit 131A, may be included in the non-integrated circuit unit. In embodiments of the present invention, the integrated circuit 131A is physically implemented on one chip. Components included in the non-integrated circuit unit may be discrete commercial devices. The non-integrated circuit unit may be implemented differently depending on the embodiment. The non-integrated circuit part may be modified so that the same single chip integrated circuit 131A can be applied to the active current compensation device 100 of various designs.

The single chip integrated circuit 131A may include an npn BJT 11, a pnp BJT 12, a diode 13, and one or more resistors.

In one embodiment, one or more resistors included in the integrated circuit 131A may include R _npn , R _pnp , and/or R _e . Within the integrated circuit 131A, the resistor R _npn may connect the collector node and the base node of the npn BJT 11. Within the integrated circuit 131A, a resistor R _pnp may connect the collector node and the base node of the pnp BJT 12. Within the integrated circuit 131A, resistance R _e may connect the emitter node of the npn BJT 11 and the emitter node of the pnp BJT 12.

The power supply 400 may supply a DC voltage V _dc between the collector node of the npn BJP 11 and the collector node of the pnp BJT 12 in order to drive the amplifier 130A. The collector node of the pnp BJT 12 may correspond to the second reference potential 602, and the collector node of the npn BJT 11 may correspond to the supply voltage of the power supply 400 based on the second reference potential 602. It can correspond to (V _dc ).

In one embodiment, the biasing diode 13 may connect the base node of the npn BJT 11 and the base node of the pnp BJT 12 within the integrated circuit 131A. That is, one end of the diode 13 may be connected to the base node of the npn BJT (11), and the other end of the diode 13 may be connected to the base node of the pnp BJT (12).

According to embodiments of the present invention, the resistors R _npn , R _pnp , R _e , and/or the biasing diode 13 included in the integrated circuit unit 131A are connected to the DC bias of the BJTs 11 and 12. can be used In one embodiment of the present invention, the resistors R _npn , R _pnp , R _e , and the biasing diode 13 are general-purpose components in various active current compensation devices (100, 100A), so they can be integrated on a single chip (one-chip) It may be integrated into the circuit unit 131A.

A single-chip integrated circuit (one-chip IC) 131A according to an embodiment of the present invention has a terminal (b1) corresponding to the base of the npn BJT (11), and a terminal (c1) corresponding to the collector of the npn BJT (11). , a terminal (e1) corresponding to the emitter of the npn BJT (11), a terminal (b2) corresponding to the base of the pnp BJT (12), a terminal (c1) corresponding to the collector of the pnp BJT (12), and a terminal (c1) corresponding to the collector of the pnp BJT (12). It may include a terminal (e1) corresponding to the emitter of (12). However, it is not limited to this, and the single chip integrated circuit 131A may further include other terminals in addition to the terminals b1, b2, c1, c2, e1, and e2.

In various embodiments, at least one of terminals b1, b2, c1, c2, e1, and e2 of the single chip integrated circuit 131A may be connected to a non-integrated circuit unit. The single chip integrated circuit 131A and the non-integrated circuit unit may be combined together to function as an amplification unit 130A according to an embodiment.

In one embodiment, the non-integrated circuit unit may include capacitors C _b , C _e , and C _dc , and impedances Z ₁ and Z ₂ .

According to one embodiment, the capacitor C _b of the non-integrated circuit unit may be connected to the base terminals b1 and b2 of the integrated circuit (one-chip IC) 131A chip, respectively. A capacitor C _e of the non-integrated circuit unit may be connected to the emitter terminals e1 and e2 of the integrated circuit 131A chip, respectively. Outside the integrated circuit 131A, the collector terminal c2 of the pnp BJT 12 may be connected to the second reference potential 602. Outside of the integrated circuit 131A, a power supply 400 may be connected between both collector terminals c1 and c2. A capacitor C _dc of the non-integrated circuit may be connected between both collector terminals c1 and c2 outside the integrated circuit 131A.

Capacitors C _b and C _e included in the non-integrated circuit unit can block the DC voltage at the base node and emitter node of the BJT (11, 12). Capacitors C _b and C _e can selectively couple only alternating current (AC) signals.

Capacitor C _dc is a DC decoupling capacitor for voltage V _dc , and may be connected in parallel with respect to the supply voltage V _dc of the power supply 400. Capacitor C _dc can selectively couple only AC signals between both collectors of the npn BJT (11) and pnp BJT (12).

The current gain of the amplification unit 130A can be controlled by the ratio of impedance Z ₁ and Z ₂ . Z ₁ and Z ₂ can be flexibly designed according to the required target current gain and the turns ratio of the sensing transformer (120A) and the compensation transformer (140A). Accordingly, Z ₁ and Z ₂ may be implemented outside of the one-chip integrated circuit 131A (i.e., in a non-integrated circuit portion).

The combination of the integrated circuit 131A and the non-integrated circuit parts C _b , C _e , C _dc , Z ₁ , and Z ₂ may function as an amplification unit 130A according to an embodiment. For example, the amplifier 130A may have a push-pull amplifier structure including an npn BJT and a pnp BJT.

In one embodiment, the secondary side 122A of the sensing transformer 120A may be connected between the base side and the emitter side of the BJTs 11 and 12. In one embodiment, the primary side 141A of the compensation transformer 140A may be connected between the collector side and the base side of the BJTs 11 and 12. Here, connection includes cases of indirect connection.

In one embodiment, the amplification unit 130A may have a return structure that injects the output current back into the base of the BJTs 11 and 12. Due to the regression structure, the amplification unit 130A can stably obtain a constant current gain for operation of the active current compensation device 100A-1.

For example, in the case of a positive swing where the input voltage of the amplifier 130A due to a noise signal is greater than 0, the npn BJT 11 may operate. At this time, the operating current may flow through the first path passing through the npn BJT (11). In the case of a negative swing where the input voltage of the amplifier 130A due to noise is less than 0, the pnp BJT 12 may operate. At this time, the operating current may flow through the second path passing through the pnp BJT (12).

In the integrated circuit 131A, resistors R _npn , R _pnp , and R _e can adjust the operating point of the BJT. Resistance R _npn , R _pnp , and R _e can be designed according to the operating point of the BJT.

According to an embodiment of the present invention, devices having temperature characteristics can be integrated into a single-chip integrated circuit (one-chip IC) 131A. According to one embodiment, the npn BJT 11, the pnp BJT 12, the biasing diode 13, R _npn , R _pnp , and R _e may be integrated into a single chip integrated circuit 131A. When integrated on a single chip, the size of the amplifier 130A can be minimized compared to when discrete elements are used. In this document, devices having temperature characteristics may refer to devices having certain circuit characteristics over a wide temperature range, for example, from extremely low temperatures to high temperatures. Devices having temperature characteristics may refer to devices whose device characteristics vary depending on temperature changes in a wide temperature range. According to an embodiment of the present invention, by internalizing an active element with temperature characteristics into the single-chip integrated circuit 131A, a single-chip integrated circuit 131A with constant (or stable) circuit characteristics despite temperature changes can be implemented. According to an embodiment of the present invention, by internalizing an active element with temperature characteristics into a single chip integrated circuit (131A), an amplifier (130A) and an active current compensation device (100A-1) that provide constant performance despite temperature changes can be implemented. there is. That is, the single chip integrated circuit 131A can be designed so that the amplification unit 130A provides constant performance despite temperature changes. Here, the meaning of the amplification unit 130A producing a certain performance includes maintaining stable performance within a certain range.

Additionally, according to an embodiment of the present invention, devices having temperature characteristics (e.g., BJTs 11 and 12, diodes 13, _Re, etc.) may share the temperature. Therefore, it can be easy to predict temperature-dependent characteristics through, for example, simulation. Therefore, it is possible to design an amplification unit 130A that is controllable and predictable despite temperature changes. On the other hand, if discrete elements such as BJTs, diodes, and resistors are used, the temperature characteristics of the elements may be different, making it difficult to predict the operation of the active circuit part.

Additionally, according to an embodiment of the present invention, even if the number of semiconductor devices increases, the increase in size and production cost of the integrated circuit 131A and the active current compensation device 100A may be minimal. Therefore, mass production of the single chip integrated circuit 131A and the active compensation device 100A may be easy.

The inductor, capacitor (eg, C _b , C _e , C _dc ), Z ₁ and Z ₂ of the non-integrated circuit part are individual components and may be implemented around the single chip integrated circuit 131A.

The capacitance required for capacitors C _b , C _e , and C _dc to couple an alternating current (AC) signal may be several μF or more (e.g., 10 μF). Since this capacitance value is difficult to implement within a single chip integrated circuit, the capacitors C _b , C _e , and C _dc may be implemented outside of the integrated circuit 131A, that is, in a non-integrated circuit part.

Depending on the design of the non-integrated circuit portion, the single chip integrated circuit 131A may be used for the first device 300 (or the second device 200) of various power systems. For example, the single chip integrated circuit 131A may be independent of the rated power of the first device 300, and the non-integrated circuit may be designed according to the rated power of the first device 300. For example, the values of impedance Z ₁ and Z ₂ may be determined based on the turns ratio of the sensing transformer 120A and the compensation transformer 140A, and the target current gain of the amplifier 130A. The configuration of the single chip integrated circuit 131A may be independent of the turns ratio and the target current gain.

Impedances Z ₁ and Z ₂ may be implemented external to the integrated circuit, i.e., in non-integrated circuitry, to achieve design flexibility for various power systems or various first devices 300 . Z ₁ and Z ₂ can be flexibly designed according to the turns ratio of the sensing transformer (120A) and the compensation transformer (140A) and the required target current gain. By adjusting the impedance Z ₁ and Z ₂ , various current compensation devices can be designed that allow the same integrated circuit 131A to be applied to various power systems.

In particular, the size and impedance characteristics of the sensing transformer (120A) must vary depending on the maximum rated current of the first device (300). Therefore, appropriate design of Z ₁ and Z ₂ is necessary to uniformize the ratio of injection current to sensing noise current over a wide frequency range. By adjusting the turns ratio and the ratio of Z ₁ and Z ₂ of the sensing transformer (120A) and the compensation transformer (140A), the ratio of the injection current to the sensing noise current can be designed to be 1 in a wide frequency range. To this end, impedances Z ₁ and Z ₂ may be implemented outside the integrated circuit 131A for design flexibility. In one embodiment, Z ₁ may be a series connection of a resistor R ₁ and a capacitor C ₁ , and Z ₂ may be a series connection of a resistor R ₂ and a capacitor C ₂ . Since C ₁ and C ₂ are implemented additionally in series next to R ₁ and R ₂ , respectively, the ratio of injection current to sensing noise current in the low-frequency range can have better performance.

Since the integrated circuit 131A according to various embodiments of the present invention is designed with scalability in mind, it can be used in various types of active current compensation devices. The same type of integrated circuit 131A may be used in various embodiments, and the non-integrated circuit portion may be designed differently depending on the embodiment.

Meanwhile, the active current compensation device 100A-1 may further include a decoupling capacitor portion 170A on the output side (i.e., the second device 200 side). One end of each capacitor included in the decoupling capacitor unit 170A may be connected to the first large current path 111 and the second large current path 112, respectively. The opposite end of each capacitor may be connected to the first reference potential 601 of the current compensation device 100A-1.

The decoupling capacitor unit 170A may prevent the output performance of the compensation current of the active current compensation device 100A-1 from significantly changing depending on the change in the impedance value of the second device 200. The impedance (Z _Y ) of the decoupling capacitor unit 170A may be designed to have a value smaller than a specified value in the first frequency band that is the target of noise reduction. Due to the combination of the decoupling capacitor portion 170A, the current compensation device 100A-1 can be used as an independent module in any system.

According to one embodiment, the decoupling capacitor unit 170A may be omitted in the active current compensation device 100A-1.

Figure 4 schematically shows a single-chip integrated circuit (one-chip IC) 131A according to one embodiment of the present invention. A detailed description of the integrated circuit 131A is omitted as it overlaps with the above description.

The DC bias circuit of a BJT should be designed to have a constant DC operating point if possible even when temperature changes. According to embodiments of the present invention, the DC bias circuit of the BJTs 11 and 12 can be designed to have a stable DC operating point within a certain range despite temperature changes.

Referring to FIG. 4, the biasing diode 13 and resistors R _npn , R _pnp , and R _e can be used in DC bias design. To bias a BJT, the forward voltage of biasing diode 13 may need to be equal to or slightly higher than twice the base-to-emitter voltage of the BJT. In an embodiment of the present invention, the biasing diode 13 and the resistor R _e can prevent thermal runaway of the BJTs 11 and 12.

In general, when current flows through a BJT and heat is generated, the current gain of the BJT increases, which causes more heat to be generated. Thermal runaway refers to a phenomenon in which heat continues to increase due to this positive feedback, damaging the BJT.

According to an embodiment of the present invention, by providing a resistance R _e between the emitter node of the npn BJT (11) and the emitter node of the pnp BJT (12), the DC bias current can be adjusted and thermal runaway can be prevented. As the temperature increases, the resistance of R _e also increases, so the current I _e can be prevented from increasing. Therefore, resistance R _e can act as negative feedback for current I _e or heat.

According to an embodiment of the present invention, thermal runaway can be prevented by providing a diode 13 between the base node of the npn BJT 11 and the base node of the pnp BJT 12. The diode 13 has the characteristic that the forward voltage decreases compared to the forward current as the temperature increases. Therefore, in the embodiment of the present invention, the diode 13 formed between the base ends of the BJTs 11 and 12 can serve to lower the voltage between the base ends as the temperature increases. Because of this, compared to the case without the diode 13, the BJTs 11 and 12 may be turned on relatively less when the diode 13 is present. Therefore, the current I _e may relatively decrease as the temperature increases. In this way, the diode 13 can act as negative feedback for the current I _e .

As described above, for the BJTs 11 and 12, positive feedback according to temperature and negative feedback due to Re and the diode 13 act together, so that the BJTs 11 and 12 maintain a constant current range despite temperature changes. You can.

If the DC bias voltage in the npn BJT (11) and pnp BJT (12) is well balanced, the DC emitter current I _e can be obtained as in Equation 1 below.

In Equation 1, V _dc is the voltage supplied between the collector of the npn BJT (11) and the collector of the pnp BJT (12), I _d is the forward bias current of the diode 13, and V _be is the base of the BJT - is the emitter voltage, and h _fe is the current gain of the BJT. Also, in one embodiment, R _bias = R _npn = R _pnp .

In one embodiment, the values of I _d and V _be may be designed according to the IV (current-voltage) characteristics of the diode 13 and BJTs 11 and 12 in the customized integrated circuit 131A.

FIG. 5 shows simulation results of bias voltage and current according to temperature of the single chip integrated circuit 131A shown in FIG. 4. The graph shown in FIG. 5 is a DC simulation result of the integrated circuit 131A according to temperature change from -50°C to 125°C.

Ie is the DC emitter current, V _bn is the voltage of the base node of the npn BJT (11) with respect to the second reference potential 602 (i.e., DC ground reference), and V _en is the voltage with respect to the second reference potential 602. is the voltage of the emitter node of the npn BJT (11), V _bp is the voltage of the base node of the pnp BJT (12) with respect to the second reference potential 602, and V _ep is the voltage with respect to the second reference potential 602. This is the voltage of the emitter node of the pnp BJT (12).

Referring to Figure 5, V _be (= V _bn - V _en ) of npn BJT (11) and V _be (= V _ep - V _bp ) of pnp BJT (12) are maintained at about 0.75V over the entire temperature range. You can see that. Additionally, the DC bias voltage is well balanced around 6 V, which is half of V _dc . That is, the voltages (Vbn, Ven, Vbp, and Vep) of each node can be uniformly distributed according to temperature. The more uniformly the voltage at each node is distributed according to temperature changes, the more advantageous it can be for the performance of the active current compensation device (100A-1).

According to one embodiment, the current I _e can be seen to maintain a constant level in the range of about 40 to 50 mA even as the temperature increases to 125°C. While the temperature increases, the current I _e does not increase beyond a certain range, but rather decreases slightly above 40°C. In other words, the current I _e does not continuously increase even as the temperature increases, so it can be seen that thermal runaway does not occur.

As a result, thanks to the internalization of the bias resistance Re and the diode 13 in the one-chip IC 131A, thermal runaway can be prevented without using additional individual components.

On the other hand, if devices with temperature characteristics (e.g., BJT (11, 12), diode (13), Re _, etc.) are discrete devices, there is a limit to the devices' ability to share temperature. In this case, the temperature characteristics of the resistor, diode 13, and BJT (11, 12) may be different from each other. Therefore, it may be difficult to predict and control bias voltage and current according to actual temperature. Additionally, when the amplification unit is constructed with commercially available discrete elements, it is difficult to freely design IV (current-voltage) characteristics, so optimal design for an active current compensation device may be difficult. Additionally, when discrete devices are used, production costs may continue to increase depending on the number of semiconductor devices.

In embodiments of the present invention, the amplifier unit of the active current compensation device includes a single chip integrated circuit (131A), so that the emitter current Ie and voltage can be adjusted as desired in consideration of the characteristics of the semiconductor device. In embodiments of the present invention, since devices having temperature characteristics are formed in a single-chip integrated circuit (one-chip IC) and share temperature, it can be easy to predict the characteristics of the devices according to temperature. In the case of the integrated circuit 131A according to embodiments of the present invention, the size increase due to an increase in the number of semiconductor devices is minimal, and the cost increase due to mass production may also be minimal.

Figure 6 schematically shows the configuration of an active current compensation device 100A-2 according to another embodiment of the present invention. Hereinafter, descriptions of content that overlaps with the content described with reference to FIGS. 2 to 5 will be omitted.

Referring to Figure 6, the active current compensation device (100A-2) is a first current (I11, I12, I13) input in common mode to each of the high current paths (111, 112, and 113) connected to the first device (300). can be actively compensated.

For this purpose, the active current compensation device (100A-2) includes three large current paths (111, 112, 113), a sensing transformer (120A-2), an amplification unit (130A), a compensation transformer (140A), and a compensation capacitor unit (150A-2). 2) may be included.

In contrast to the active current compensation devices (100A, 100A-1) according to the above-described embodiment, the active current compensation device (100A-2) according to the embodiment shown in FIG. 6 has three large current paths (111, 112, 113), and accordingly, there is a difference between the sensing transformer (120A-2) and the compensation capacitor unit (150A-2). Therefore, hereinafter, the active current compensation device (100A-2) will be described focusing on the above-mentioned differences.

The active current compensation device 100A-2 may include a first large current path 111, a second large current path 112, and a third large current path 113 that are distinct from each other. According to one embodiment, the first high-current path 111 may be an R-phase power line, the second high-current path 112 may be an S-phase power line, and the third high-current path 113 may be a T-phase power line. The first currents I11, I12, and I13 may be input to each of the first large current path 111, the second large current path 112, and the third large current path 113 in a common mode.

The primary side (121A-2) of the sensing transformer (120A-2) is disposed in each of the first, second, and third large current paths (111, 112, and 113), and induces an induced current in the secondary side (122A-2) can be created. The magnetic flux densities generated in the sensing transformer 120A-2 by the first currents I11, I12, and I13 on the three large current paths 111, 112, and 113 may be mutually reinforced.

In the active current compensation device 100A-2 according to the embodiment shown in FIG. 6, the amplification unit 130A may correspond to the amplification unit 130A described above.

The compensation capacitor unit 150A-2 provides a path through which the compensation currents (IC1, IC2, IC3) generated by the compensation transformer (140A) flow to the first, second, and third large current paths (111, 112, and 113), respectively. can be provided.

The active current compensation device 100A-2 may further include a decoupling capacitor portion 170A-2 on the output side (i.e., the second device 200 side). One end of each capacitor included in the decoupling capacitor unit 170A-2 may be connected to the first large current path 111, the second large current path 112, and the third large current path 113, respectively. The opposite terminal of each capacitor may be connected to the first reference potential 601 of the current compensation device 100A-2.

The decoupling capacitor unit 170A-2 may prevent the output performance of the compensation current of the active current compensation device 100A-2 from significantly changing depending on the change in the impedance value of the second device 200. The impedance (Z _Y ) of the decoupling capacitor unit 170A-2 may be designed to have a value smaller than a specified value in the first frequency band that is the target of noise reduction. Due to the combination of the decoupling capacitor portion 170A-2, the current compensation device 100A-2 can be used as an independent module in any system (eg, 3-phase 3-wire system).

According to one embodiment, the decoupling capacitor unit 170A-2 may be omitted from the active current compensation device 100A-2.

The active current compensation device (100A-2) according to this embodiment can be used to compensate (or offset) the first current (I11, I12, I13) moving from the load to the power source in a three-phase, three-wire power system. .

Of course, according to the technical idea of the present invention, the active current compensation device according to various embodiments can be modified to be applied to a three-phase, four-wire system.

The amplifying unit 130A according to an embodiment of the present invention can be applied to a single-phase (2-wire) system shown in FIG. 3, a 3-phase 3-wire system shown in FIG. 6, and a 3-phase 4-wire system (not shown). there is. Since the single chip integrated circuit 131A can be applied to multiple systems, the integrated circuit 131A can have versatility in active current compensation devices according to various embodiments.

The specific implementations described in the present invention are examples and do not limit the scope of the present invention in any way. For the sake of brevity of the specification, descriptions of conventional electronic components, control systems, software, and other functional aspects of the systems may be omitted. In addition, the connections or connection members of lines between components shown in the drawings exemplify functional connections and/or physical or circuit connections, and in actual devices, various functional connections or physical connections may be replaced or added. Can be represented as connections, or circuit connections.

The spirit of the present invention should not be limited to the above-described embodiments, and the scope of the patent claims described below as well as all scopes equivalent to or equivalently changed from the scope of the claims fall within the scope of the spirit of the present invention. They will say they do it.

Claims (6)

In the active current compensation device that actively compensates for noise occurring in common mode in each of at least two large current paths,
a sensing unit that generates an output signal corresponding to the common mode noise current on the high current path;
an amplifier that amplifies the output signal to generate an amplification current; and
It includes a compensation unit that generates a compensation current based on the amplification current and causes the compensation current to flow through each of the at least two high current paths,
The amplifier unit includes a non-integrated circuit unit and a single chip integrated circuit,
Active devices whose device characteristics change depending on temperature changes are internalized in the single chip integrated circuit,
The single-chip integrated circuit is designed so that the amplifier maintains performance within a certain range even when temperature changes,
npn BJT, pnp BJT, resistor and diode are internalized in the integrated circuit of the single chip,
The resistor is connected between the emitter node of the npn BJT and the emitter node of the pnp BJT,
The diode is connected between the base node of the npn BJT and the base node of the pnp BJT,
An active current compensation device, wherein the resistor and the diode act as temperature-dependent negative feedback. delete delete According to paragraph 1,
The diode performs the function of reducing the emitter current flowing through the resistor.
Active current compensation device. According to paragraph 1,
The diode and the resistor adjust DC bias current of the npn BJT and the pnp BJT,
Active current compensation device. According to paragraph 1,
The emitter current flowing through the resistor maintains a predetermined range as the temperature changes.
Active current compensation device.

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