KR20240026976A - Active compensation device for compensating voltage and current - Google Patents

Abstract

The present invention relates to an active compensation device that actively compensates for noise occurring in common mode in each of at least two large current paths connected to a first device, in which the large current supplied by the second device is transmitted to the first device. At least two large current paths for delivering to the device, a sensing unit that senses the common mode noise current on the large current path and generates an output signal corresponding to the noise current, and amplifies the output signal of the sensing unit to generate a first amplification voltage and a second 2 an amplification unit for generating an amplification voltage, a first compensation unit for generating a compensation voltage on the high current path based on the first amplification voltage, and branching a compensation current from the large current path based on the second amplification voltage. An active compensation device is provided, including a second compensation unit that is withdrawn by a user.

Description

Active compensation device that compensates for voltage and current {ACTIVE COMPENSATION DEVICE FOR COMPENSATING VOLTAGE AND CURRENT}

Embodiments of the present invention relate to an active compensation device that compensates for voltage and current, and relates to an active compensation device that actively compensates simultaneously for noise voltage and current occurring in common mode on two or more large current paths connecting the two devices. will be.

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 that suppresses common mode noise current.

Meanwhile, with the development of technology, more and more high-power products are being released, and in high-power/high-current systems, the noise reduction performance of common mode chokes rapidly deteriorates due to magnetic saturation. Therefore, in order to prevent magnetic saturation and maintain noise reduction performance in high-power/high-current systems, conventionally, the size or number of common mode chokes had to be increased. This caused the problem that the size and price of EMI filters for high-power products increased significantly.

The present invention was devised to improve the above problems, and its purpose is to provide an active compensation device that can effectively compensate for common mode voltage and current simultaneously. For example, in high-power products, an active compensation device can be provided that can satisfy noise emission regulations by actively compensating for common mode noise without increasing the size or size of the CM choke. 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 compensation device that actively compensates for noise occurring in common mode in each of at least two high current paths connected to the first device includes a high current supplied by the second device. at least two high current paths for delivering to the first device; a sensing unit that senses the common mode noise current on the high current path and generates an output signal corresponding to the noise current; an amplification unit that amplifies the output signal of the sensing unit to generate a first amplification voltage and a second amplification voltage; a first compensation unit that generates a compensation voltage on the high current path based on the first amplification voltage; and a second compensation unit that branches and draws a compensation current from the high current path based on the second amplified voltage.

According to one embodiment, the first compensation unit is a type that generates the compensation voltage on the high current path between the sensing unit and the second device, and the second compensation unit is a type that generates the compensation voltage between the sensing unit and the first device. It may be a feedback type that branches off the compensation current from the large current path.

According to one embodiment, the sensing unit may be a CM choke on which the two or more high current paths are wound, and a wire for generating the input voltage of the amplifying unit is wound over the CM choke.

According to one embodiment, the first compensating unit may be formed so that a wire outputting the first amplified voltage of the amplifying unit passes through a core, and the high current path passes through the core or is wound one or more times.

According to one embodiment, the amplification unit includes a first amplification unit that outputs the first amplification voltage and a second amplification unit that outputs the second amplification voltage, and the first compensation unit includes a first compensation transformer, The second compensation unit may include a second compensation transformer that generates an induced voltage in a path through which the compensation current is drawn based on the second amplified voltage.

According to one embodiment, the second compensation unit may further include a compensation capacitor unit made of a Y-capacitor branched from the high current path and connected to the secondary side of the second compensation transformer.

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.

According to various embodiments of the present invention as described above, it is possible to provide a compensation device whose price, area, volume, and weight do not significantly increase even in a high-power system. For example, in high-power products, price, area, volume, and weight can be reduced compared to passive filters that only include CM chokes by actively compensating for common-mode noise voltage and current without increasing the size or size of the CM choke. .

According to various embodiments of the present invention, common mode voltage and current can be compensated at the same time, and noise can be reduced more effectively.

Through this, the present invention can provide an active compensation device that can perform current and voltage compensation functions regardless of the load of the surrounding situation on the side where EMI noise is emitted.

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 compensation device 100 according to an embodiment of the present invention.
FIG. 2 schematically shows an active compensation device 100A according to an embodiment of the present invention as a specific example of the active compensation device shown in FIG. 1.
FIG. 3 schematically shows an active compensation device 100B according to an embodiment of the present invention as a specific example of the active compensation device shown in FIG. 2.
4 to 6 schematically show active compensation devices 100C-1, 100C-2, and 100C-3 according to an embodiment of the present invention as a specific example of the active compensation device shown in FIG. 3. .
Figure 7 schematically shows the configuration of a system including an active compensation device 100D according to another embodiment of the present invention.
Figure 8 schematically shows the configuration of a system including an active compensation device 100E 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. If an embodiment can be implemented differently, a specific process sequence may be performed differently from the described sequence. In the following embodiments, when areas, components, parts, units, modules, etc. are connected, not only are the areas, components, parts, units, and modules directly connected, but also the areas, components, parts, units, and modules are connected. This also includes cases where other areas, components, parts, units, and modules are interposed and indirectly connected.

Figure 1 schematically shows the configuration of a system including an active compensation device 100 according to an embodiment of the present invention. The active compensation device 100 is a current I _n (e.g., EMI noise current) and voltage V generated in common mode (CM) on two or more large current paths 111 and 112 from the first device 300. _n (e.g. EMI noise voltage) can be actively compensated.

Referring to FIG. 1 , the active compensation device 100 may include a sensing unit 120, an amplifying unit 130, a first compensation unit 140, and a second compensation unit 160.

In this specification, the first device 300 may be various types of devices 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 device of various types 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 it may be a device that supplies power produced by another device (for example, an electric vehicle charging device). Of course, 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, due to the switching operation of the power conversion device, common mode noise current I _n may be generated on the high current paths 111 and 112. Or, for example, noise current leaked from the first device 300 may flow into the large current paths 111 and 112 through the second device 200 via the ground, thereby generating noise current I _n .

The noise current I _n occurring in the same direction on the large current paths 111 and 112 may be referred to as a common mode noise current. Additionally, the common mode noise voltage V _n may be a voltage generated between the ground (e.g., reference potential 1) and the large current paths 111 and 112, rather than a voltage generated between the large current paths 111 and 112.

For example, the first device 300 may correspond to a noise source, and the second device 200 may correspond to a noise receiver.

The two or more large current paths 111 and 112 may be paths for transmitting power supplied by the second device 200, that is, large currents I21 and I22, to the first device 300. For example, they may be power lines. 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 compensation device 100. The large 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 the noise current I _n is transmitted from the first device 300 to the second device 200. Alternatively, it may be a path in which noise voltage V _n is generated with respect to the ground (e.g., reference potential 1).

The noise current I _n or the noise voltage V _n may be input in common mode for each of the two or more large current paths 111 and 112. The noise current I _n may be a current unintentionally generated in the first device 300 due to various causes. For example, the noise current I _n may be a noise current due to parasitic capacitance between the first device 300 and the surrounding environment. Alternatively, the noise current I _n may be a noise current generated by a switching operation of the power conversion device of the first device 300. The noise current I _n and the noise voltage V _n may have 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.

In the drawing, the noise current I _n and the noise voltage V _n are shown between the node where the second compensation unit 160 and the large current paths 111 and 112 meet and the sensing unit 120, but in this document, they are referred to as 'noise current' The term 'noise voltage' is not limited thereto, and may refer to voltage and current that may occur in a common mode with a first frequency throughout the large current paths 111 and 112.

Meanwhile, the two or more large current paths 111 and 112 may include two paths as shown in FIG. 1, three paths (e.g., a three-phase, three-wire power system), or four paths (e.g., a three-phase, four-wire power system). line power system). 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 noise current I _n on the two or more large current paths 111 and 112, and generate an output signal corresponding to the noise current I _n to the amplifying unit 130. In other words, the sensing unit 120 may mean a means for detecting the noise current I _n 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 noise current I _n , but the portion where the output signal by sensing is generated within the sensing unit 120 is a large current. It may be insulated from the paths 111 and 112. For example, the sensing unit 120 may be implemented as a sensing transformer. For example, the sensing unit 120 may be in the form of a CM choke on which power lines corresponding to the high current paths 111 and 112 are wound, and the wire on the amplifying unit 130 is wound over the CM choke. The sensing transformer may sense the noise current I _n on the high current paths 111 and 112 while being insulated from the high current paths 111 and 112.

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 amplification unit 130 may include OP-AMP. For example, the amplifier 130 may include a plurality of passive elements such as resistors and capacitors in addition to the OP-AMP. In another 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. The reference potential of the amplifier 130 (reference potential 2) and the reference potential of the compensation device 100 (reference potential 1) may be different potentials.

The amplifier unit 130 receives power from the third device 400, which is distinct from the first device 300 and/or the second device 200, and amplifies the output signal output by the sensing unit 120. It can generate electric current. At this time, the third 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 third 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 output signal amplified by the amplifier 130 may be input to the first compensation unit 140 and the second compensation unit 160. For example, the amplification current output from the amplifying unit 130 may flow toward the first compensating unit 140 and the second compensating unit 160, respectively. For example, the amplification unit 130 includes a first amplification unit that outputs a first amplification current (or a first amplification voltage) to the first compensation unit 140, and a second amplification unit to output a first amplification current (or first amplification voltage) to the second compensation unit 160. It may be composed of a second amplification unit that outputs a current (or a second amplification voltage).

The active compensation device 100 according to an embodiment of the present invention includes a first compensation unit 140 and a second compensation unit 160.

The first compensation unit 140 is a type of compensation unit that compensates for the voltage in front or behind the CM choke in preparation for noise input from the first device 300. The second compensation unit 160 is a feedback type compensation unit that compensates for noise by going back to the rear end.

The first compensator 140 may generate a compensation voltage in series on the high current paths 111 and 112 based on the amplified voltage output from the amplification unit 130. The output side of the first compensator 140 may generate a compensation voltage in series to the high current paths 111 and 112, but may be isolated from the amplification unit 130. For example, the first compensation unit 140 may be made of a compensation transformer for the insulation. For example, the output signal (e.g., output voltage) of the amplifier 130 may be applied to the primary side of the compensation transformer, and a compensation voltage based on the output signal may be generated on the secondary side of the compensation transformer. The compensation voltage can have the effect of suppressing the noise current I _n flowing on the large current paths 111 and 112.

The second compensator 160 may generate a compensation current based on the output signal amplified by the amplifier 130 and output to the second compensator 160. The second compensation unit 160 is connected to the high current paths 111 and 112, respectively, and can cause compensation current to flow from the high current paths 111 and 112 to the reference potential 1. For example, in the second compensation unit 160, the compensation current may be branched from the large current paths 111 and 112. Through this, the noise current I _n flowing on the large current paths 111 and 112 can be compensated. The output side of the second compensator 160 may be connected to the high current paths 111 and 112 to compensate for the noise current I _n on the high current paths 111 and 112, but may be insulated from the amplification unit 130. For example, the second compensation unit 160 may include a compensation transformer for the insulation. For example, the output voltage of the amplifier 130 may be applied to the primary side of the compensation transformer, and a compensation current based on the transformation of the output voltage may be generated on the secondary side of the compensation transformer. The compensation current may reduce the noise current I _n by allowing at least a portion of the noise current I _n to flow to the ground (eg, reference potential 1).

The active compensation device 100 according to various embodiments of the present invention as described above may have a structure that combines voltage compensation and current compensation. For example, the first compensator 140 can compensate for voltage and the second compensator 160 can compensate for current.

FIG. 2 shows a more specific example of the embodiment shown in FIG. 1 and schematically shows an active compensation device 100A according to an embodiment of the present invention. The active compensation device 100A may include a sensing unit 120, a first amplification unit 131, a second amplification unit 132, a first compensation unit 140, and a second compensation unit 160. .

The large current paths 111 and 112, the sensing unit 120, the first and second compensation units 140 and 160, and the third device 400 shown in relation to the active compensation device 100A of FIG. 2. , the description of reference potential 1 and reference potential 2 corresponds to the description of FIG. 1.

Additionally, in FIG. 2 and the drawings below, the first device 300 and the second device 200 may be omitted. That is, the high current paths 111 and 112 at the front end (e.g., the first compensator 140 side) of the active compensation device 100A may be connected to the power line of the second device 200, and the high current paths 111 and 112 at the rear end (e.g., the second compensator 140 side) may be connected to the power line of the second device 200. The high current paths 111 and 112 on the compensator 160 side may be connected to the power line of the first device 300.

The active compensation device 100A according to an embodiment of the present invention may include a first amplification unit 131 and a second amplification unit 132.

The sensing unit 120 may sense the noise current I _n on the large current paths 111 and 112 and generate an output signal toward the first amplification unit 131 and the second amplification unit 132. The output signal may correspond to the voltage between nodes a and b. Nodes a and b may be differentially connected to the input terminal of the first amplifier 131 and may also be differentially connected to the input terminal of the second amplifier 132. Accordingly, the voltage between nodes a and b may be input as an input voltage to the first amplification unit 131 and the second amplification unit 132.

The first amplifier 131 and the second amplifier 132 may each amplify the input voltage and output separate output signals (eg, output voltages). At this time, the gain (eg, voltage gain) of the first amplifier 131 and the gain (eg, voltage gain) of the second amplifier 132 may be different from each other.

The amplified voltage V ₁ output from the first amplification unit 131 becomes the input signal of the first compensator 140, and the first compensator 140 operates the high current paths 111 and 112 based on the V ₁ A compensation voltage can be generated in series across the phases.

The amplified voltage V ₂ output from the second amplification unit 132 becomes the input signal of the second compensation unit 160. The second compensation unit 160 can reduce the noise current I _n by flowing a compensation current from the high current paths 111 and 112 to the reference potential 1 based on the V ₂ .

The first amplification unit 131 and the second amplification unit 132 are expressed separately in terms of function, but according to one embodiment, the first amplification unit 131 and the second amplification unit 132 are implemented as one IC. possible.

Meanwhile, the first compensation unit 140 and the second compensation unit 160 each use a compensation transformer to insulate the large current paths 111 and 112 from the first amplifier 131 and the second amplifier 132. may include.

FIG. 3 shows a more specific example of the embodiment shown in FIG. 2 and schematically shows an active compensation device 100B according to an embodiment of the present invention.

The active compensation device 100B can actively compensate for noise current I _n or noise voltage V _n input in common mode to each of the two large current paths 111 and 112 connected to the first device 300.

Referring to FIG. 2, the active compensation device 100B includes a sensing transformer 120B, a first amplifier 131B, a second amplifier 132B, and a first amplifier disposed on the output side of the first amplifier 131B. 1 It may include a compensation transformer 140B, a second compensation transformer 161B disposed on the output side of the second amplifier 132B, and a compensation capacitor unit 162B.

In one embodiment, the above-described sensing unit 120 may include a sensing transformer 120B. At this time, the sensing transformer (120B) is insulated from the high current path (111, 112) and the voltage induced at both ends of the sensing transformer (120B) due to the noise current I _n or noise current I _n on the high current path (111, 112). It may be a means to detect. The sensing transformer (120B) is induced at both ends of the sensing transformer (120B) due to the noise current I _n or the noise current I _n input from the first device 300 side to the high current path 111, 112 (e.g., power line). Voltage can be sensed.

The sensing transformer 120B includes a primary side 121 disposed on the high current path 111 and 112, and a secondary side 122 differentially connected to the input terminals of the amplifiers 131B and 132B. can do. The sensing transformer 120B is located on the primary side 121B (e.g., primary winding) disposed on the high current path 111, 112, and on the secondary side 122 based on the magnetic flux density induced by the noise current I _n . ) (e.g. secondary winding) can generate induced current or induced voltage. The primary side 121 of the sensing transformer 120B may be, for example, a winding in which a first high current path 111 and a second high current path 112 are each wound around one core.

According to one embodiment of the present invention, the sensing transformer (120B) has a secondary side (122) wire wrapped around a CM choke on which the first large current path 111 and the second large current path 112 are wound. It can be. In this way, when the sensing transformer 120B is formed using the CM choke, the sensing transformer 120B not only performs the functions of sensing and transforming, but also can function as a passive filter as the CM choke. That is, when the sensing transformer (120B) is formed by wrapping the secondary side (122) wire around the CM choke, the sensing transformer (120B) senses and transforms the noise current I _n , and suppresses or suppresses the noise current I _n . It can play a deterrent role at the same time. Meanwhile, along with the above-described CM choke, active compensation devices (100, 100A, 100B, 100C-1, 100C-2) according to various embodiments of the present invention are added, so that even in a high-power system, common Mode noise voltage and current can be effectively reduced.

Specifically, the sensing transformer 120B has a magnetic flux density induced by the noise current I _n on the first large current path 111 (e.g., a live line) and a noise current on the second large current path 112 (e.g., a neutral line). The magnetic flux densities induced by I _n may be configured to overlap (or reinforce) each other. At this time, large currents (I21, I22) also flow on the large current paths (111, 112), and the magnetic flux density induced by the large current (I21) on the first large current path (111) and the large current (I22) on the second large current path (112) The magnetic flux densities induced by I22) can be configured to cancel each other. Also, as an example, the sensing transformer 120B may determine that the magnitude of the magnetic flux density induced by the noise current I _n in the first frequency band (e.g., a band ranging from 150 KHz to 30 MHz) is determined by the second frequency band (e.g. For example, it may be configured to be larger than the size of the magnetic flux density induced by the large current (I21, I22) in the range of 50Hz to 60Hz.

In this way, the sensing transformer 120B is configured so that the magnetic flux densities induced by the large currents I21 and I22 cancel each other, so that only the noise current I _n can be sensed. That is, the voltage induced in the secondary side 122 of the sensing transformer 120B may be a voltage obtained by converting the induced voltage in the primary side 121 according to the noise current I _n at a certain ratio.

For example, in the sensing transformer 120B, the turns ratio of the primary side 121 and the secondary side 122 is 1:N _sen , and the self-inductance of the primary side 121 of the sensing transformer 120B is L. When _sen , the secondary side 122 may have a self-inductance of N _sen ² L _sen . For example, the primary side 121 and the secondary side 122 of the sensing transformer 120B may be combined with a predetermined coupling coefficient.

For example, if the voltage induced on both ends of the primary side 121 of the sensing transformer 120B due to the noise current I _n is V _choke , the voltage V _sen induced on the secondary side 122 is V _choke . is N _sen times.

Meanwhile, the secondary side 122 of the sensing transformer 120B may be connected in parallel with the input terminal of the first amplifier 131B and the input terminal of the second amplifier 132B. For example, the secondary side 122 of the sensing transformer 120B is differentially connected in parallel with the input terminal of the first amplifier 131B and the input terminal of the second amplifier 132B, and the first amplifier 131B and An induced voltage (V _sen ) may be supplied to the second amplifier 132B.

The first amplification unit 131B and the second amplification unit 132B may be examples of the above-described amplification unit 130, and correspond to the above-described first amplification unit 131 and the second amplification unit 132, respectively. can do. Each of the first amplifier 131B and the second amplifier 132B may amplify the induced voltage V _sen detected by the sensing transformer 120B and induced in the secondary side 122. For example, the amplification units 131B and 132B may amplify the magnitude of the induced voltage V _sen at a certain rate and/or adjust the phase.

The voltage gain G ₁ of the first amplification unit 131B and the voltage gain G ₂ of the second amplification unit 132B may be different from each other. According to one embodiment of the present invention, the voltage gain G ₂ of the second amplifier 132B may be designed to be greater than the voltage gain G ₁ of the first amplifier 131B. A detailed description of this will be provided later. However, it is not limited to this, and G ₁ and G ₂ may be determined according to various embodiments.

The output voltage V ₁ of the first amplifier 131B can be expressed as Equation 2 below.

The output voltage V ₁ of the first amplifier 131B becomes the input voltage of the first compensation transformer 140B. That is, the output voltage V ₁ of the first amplification unit 131B becomes the primary side 141 voltage of the first compensation transformer 140B, and the first compensation transformer 140B produces the secondary side (141) based on V ₁ A compensation voltage V _inj1 can be generated in series on the large current paths 111 and 112 (142).

The first compensation transformer 140B may correspond to the first compensation unit 140 described above. The first compensation transformer 140B may be a means for insulating the amplification units 131B and 132B including active elements from the high current paths 111 and 112. That is, the first compensation transformer 140B is insulated from the high current paths 111 and 112 and applies a compensation voltage V _inj1 to the high current paths 111 and 112 based on the output voltage V ₁ of the first amplifier 131B. Induction may be a means for voltage compensation.

For example, the first compensation transformer 140B may have a structure in which the primary side 141 wire and the secondary side 142 wire pass through one core or are wound at least once. The primary side 141 wire is a wire through which the output signal of the first amplifier 131B flows, and the secondary side 142 wire may correspond to the high current paths 111 and 112.

The first compensation transformer 140B may induce a compensation voltage V _inj1 on the high current paths 111 and 112 of the secondary side 142 based on the amplified voltage V ₁ generated on the primary side 141.

For example, in the first compensation transformer 140B, if the turns ratio of the primary side 141 and the secondary side 142 is 1:N _inj1 , the voltage V _inj1 induced in the secondary side 142 is V It is N _inj1 times ₁ . Therefore, the compensation voltage V _inj1 can be expressed as Equation 3.

Meanwhile, when the voltage gain of the second amplifier 132B is G ₂ , the output voltage V ₂ of the second amplifier 132B can be expressed as Equation 4 below.

The output voltage V ₂ of the second amplification unit 132B becomes the input voltage of the second compensation unit 160, that is, the input voltage of the second compensation transformer 161B.

A configuration in which the second compensation transformer 161B and the compensation capacitor unit 162B are combined may correspond to the above-described second compensation unit 160. The output voltage V ₂ of the second amplifier 132B becomes the primary side voltage of the second compensation transformer. The second compensation transformer 161B may be a means for insulating the amplification units 131B and 132B, which include active elements, from the high current paths 111 and 112. That is, the second compensation transformer (161B) is insulated from the large current paths (111, 112) and generates a compensation current Icy on the secondary side of the second compensation transformer (161B) for branching from the large current paths (111, 112). It may be a means to do so.

The second compensation transformer 161B has a primary side differentially connected to the output terminal of the second amplifier 132B and a secondary side connected through the high current paths 111 and 112 and the compensation capacitor section 162B. Sides may be included.

The second compensation transformer 161B may induce an induced voltage V ₃ on the secondary side based on the amplified voltage V ₂ generated on the primary side. For example, in the second compensation transformer 161B, if the turns ratio of the primary side and the secondary side is 1:N _inj2 , the voltage V ₃ induced in the secondary side is N _inj2 times that of V ₂ . Therefore, the induced voltage V ₃ can be expressed as Equation 5.

The secondary side of the second compensation transformer 161B may be placed on a path connecting the compensation capacitor unit 162B, which will be described later, and the reference potential (reference potential 1) of the compensation device 100B. That is, one end of the secondary side of the second compensation transformer (161B) is connected to the high current path (111, 112) through the compensation capacitor unit (162B), and the other end of the secondary side is connected to the active compensation device (100B). It can be connected to the reference potential (reference potential 1). Meanwhile, the primary side of the second compensation transformer (161B), the primary side (141) of the first compensation transformer (140B), the amplifier units (131B, 132B), and the secondary side (122) of the sensing transformer (120B) may be connected to a reference potential (reference potential 2) that is distinct from the remaining components of the active compensation device (100B). The reference potential (reference potential 1) of the compensation device 100B and the reference potential (reference potential 2) of the amplification units 131B and 132B can be distinguished.

As such, the present invention uses a different reference potential for the component that generates the compensation current from the remaining components and uses a separate power source, thereby allowing the component that generates the compensation current to operate in an insulated state. The reliability of the active compensation device 100B can be improved.

The voltage V ₃ converted through the second compensation transformer 161B may draw a compensation current I _cy from the high current paths 111 and 112 (eg, power line) through the compensation capacitor unit 162B.

The compensation capacitor unit 162B may provide a path through which at least a portion of the noise current on the large current paths 111 and 112 is drawn to the secondary side of the second compensation transformer 161B.

The compensation capacitor unit 162B includes two Y-capacitors (Y-capacitors, Y), one end of which is connected to the secondary side of the second compensation transformer 161B, and the other end of which is connected to the high current paths 111 and 112. -cap) may be included. One end of each of the two Y-caps shares a node connected to the secondary side of the second compensation transformer (161B), and the opposite ends of each of the two Y-caps are connected to the first high current path 111 and the second high current path 111, respectively. It may have a node connected to the high current path 112.

The compensation capacitor unit 162B may draw compensation current I _cy from the power line based on the voltage V ₃ induced by the second compensation transformer 161B. As the compensation current I _cy compensates (or cancels out) the noise current on the high current paths 111 and 112, the compensation device 100B can reduce noise.

Meanwhile, the common mode noise voltage of the node where the compensation capacitor unit 162B meets the high current paths 111 and 112 is V _n , and the voltage between the first compensation transformer 140B and the second device 200 is V _LISN. , and solving the circuit equation between V _n and V _LISN is as shown in Equation 6 below. V _n and V _LISN may represent the potential for reference potential 1 (eg, ground).

Meanwhile, since the noise emitted toward the second device 200 by the operation of the active compensation device 100B should correspond to almost 0, V _LISN should correspond to 0, and Equation 7 below can be derived.

Meanwhile, using this, the effective impedance of the large current paths 111 and 112 at the point between the sensing transformer 120B and the compensation capacitor unit 162B can be calculated as shown in Equation 8.

In Equation 8, s*L _choke may represent the impedance of the CM choke included in the sensing transformer (120B). Therefore, Z _line,eff is that the impedance on the large current path (111, 112) (viewed from point V _n ) is ' than the impedance s*L _choke of the CM choke. ' Indicates that the effect is doubled.

This may be an effect of the first amplifier 131 (eg, first amplifier 131B) and the first compensation unit 140 (eg, first compensation transformer 140B). The first amplifier 131 and the first compensation unit 140 can perform voltage compensation (V _inj1 ) on the high current path, which gives an effect corresponding to the effect of increasing the inductance and suppresses noise current from flowing. You can do it (L boost type).

In other words, the active compensation device (100B) according to an embodiment of the present invention has a lower inductance than the CM choke's inductance L _choke . 'Since it can have the effect of a twofold increase in effective inductance L _choke,eff (Equation 9), the noise suppression effect can be increased compared to when only the CM choke exists.

For example, the noise suppression effect can be adjusted according to the voltage gain G ₁ of the first amplifier 131B, the turns ratio N _sen of the sensing transformer 120B, and the turns ratio N _inj1 of the first compensation transformer 140B.

Meanwhile, if the circuit equation between the node (V _n ) where the compensation capacitor unit 162B meets the high current paths 111 and 112 and the reference potential 1 is solved, it becomes Equation 10 below.

Here, C _y is the capacitance of the Y-capacitor included in the compensation capacitor unit 162B. Meanwhile, using this, the effective Y-impedance Z _cy,eff viewed from the node (V _n ) where the compensation capacitor unit 162B and the large current paths 111 and 112 meet toward the compensation capacitor unit 162B is expressed as Equation 11: can be calculated.

Equation 11 above is obtained by substituting Equation 7 for V _choke . In Equation 11, 1/(s*C _y ) represents the impedance of the Y-capacitor included in the compensation capacitor unit 162B. Z _cy,eff represents the effective Y-impedance viewed toward the compensation capacitor unit 162B from the node where the compensation capacitor unit 162B and the high current paths 111 and 112 meet.

Referring to Equation 11, the effective Y-impedance Z _cy,eff is ' than the impedance 1/(s*C _y ) of the Y-capacitor. 'Indicates that it has a fold-reduced effect.

This may be an effect of the second amplification unit 132 (e.g., second amplification unit 132B) and the second compensation unit 160 (e.g., first compensation transformer 161B and compensation capacitor unit 162B). there is. The second amplifier 132 and the second compensation unit 142 are of the feedback type and can provide current compensation (I _cy ) so that the noise current is branched from the high current path, which has the effect of increasing the Y-capacitance. By giving a corresponding effect, noise can be effectively drawn to the ground (i.e., reference potential 1) (C boost type).

In other words, the active compensation device 100B according to an embodiment of the present invention has a capacitance C _y of the Y-capacitor. 'Since it can have the effect of a twofold increase in effective Y-capacitance C _y,eff (Equation 12), the noise extraction effect can be increased compared to when only Y-capacitance exists.

For example, the noise extraction effect is caused by the voltage gain G ₁ of the first amplifier 131B, the voltage gain G ₂ of the second amplifier 132B, the turns ratio N _inj1 of the first compensation transformer 140B, and the second compensation transformer ( 161B) can be adjusted according to the turns ratio N _inj2 .

For example, in the first compensation transformer 140B, the primary side 141 wire passes through the core, and the secondary side 142 wire (i.e., high current path 111, 112) passes through the core or once. It can be formed to be wound.

4 to 6 are specific examples of the active compensation device shown in FIG. 3, and schematically show active compensation devices 100C-1, 100C-2, and 100C-3 according to an embodiment of the present invention. .

The compensation device 100C-1 according to an embodiment shown in FIG. 4 includes a sensing transformer 120C, a first amplifier 131C, a second amplifier 132C, a first compensation transformer 140C-1, and a first compensation transformer 140C-1. 2 It may include a compensation transformer (161C) and a compensation capacitor unit (162C).

The compensation device 100C-2 according to an embodiment shown in FIG. 5 includes a sensing transformer 120C, a first amplifier 131C, a second amplifier 132C, a first compensation transformer 140C-2, and a first compensation transformer 140C-2. 2 It may include a compensation transformer (161C) and a compensation capacitor unit (162C).

The compensation device 100C-1 shows an embodiment in which the primary side wire and the secondary side large current paths 111 and 112 of the first compensation transformer 140C-1 pass through the core, and the turns ratio N _inj1 is about 1. It may be to some extent.

The compensation device (100C-2) shows an embodiment in which the primary side wire of the first compensation transformer (140C-2) passes through the core and the secondary side large current paths (111, 112) wind the core once. The turns ratio N _inj1 may be about 2.

4 and 5, a sensing transformer (120C), a first amplifier (131C), a second amplifier (132C), a first compensation transformer (140C-1, 140C-2), a second compensation transformer (161C), and a compensation capacitor. The unit 162C includes the sensing transformer 120B, the first amplifier 131B, the second amplifier 132B, the first compensation transformer 140B, the second compensation transformer 161B, and the compensation capacitor unit ( Corresponds to the description in 162B).

4 and 5, in the active compensation device (100C-1, 100C-2) according to an embodiment of the present invention, the sensing transformer (120C) is the first compensation transformer (140C-1, 140C-2) ) and may be a different type of device from the second compensation transformer (161C).

For example, unlike the first compensation transformer (140C-1, 140C-2) and the second compensation transformer (161C) that only perform the role of a transformer, the sensing transformer (120C) corresponds to the large current path (111, 112). The wires on the amplification unit (131C, 132C) may be wrapped around a CM choke with a power line wrapped around it. The CM choke is a passive filter that can suppress noise current using inductance, and the sensing transformer (120C) can sense noise by simply wrapping the secondary wire around the CM choke.

Meanwhile, the compensation device 100C-3 according to an embodiment shown in FIG. 6 includes a sensing transformer 120C, a first amplifier 131C, a second amplifier 132C, and a first compensation transformer 140C-3. , it may include a second compensation transformer (161C) and a compensation capacitor unit (162C).

The active compensation device 100C-3 according to an embodiment can actively compensate for the noise current I _n or the noise voltage V _n generated in the common mode in the large current paths 111 and 112.

Sensing transformer (120C), first amplifier (131C), second amplifier (132C), first compensation transformer (140C-3), second compensation transformer (161C), compensation included in the active compensation device (100C-3) The capacitor unit 162C includes the sensing transformer 120B, the first amplifier 131B, the second amplifier 132B, the first compensation transformer 140B, the second compensation transformer 161B, and the compensation capacitor unit described in FIG. 3. It may correspond to the explanation in (162B).

In the active compensation device 100C-3 according to an embodiment, the first compensation transformer 140C-3 is connected to the sensing transformer 120C (e.g., CM), which is on the first device 300 side with respect to the sensing transformer 120C. Can be placed behind the chalk). The first compensation transformer 140C-3 may generate a compensation voltage (V _inj1 ) on the high current paths 111 and 112 between the CM choke and the first device 300.

Figure 7 schematically shows the configuration of a system including an active compensation device 100D according to another embodiment of the present invention. Hereinafter, descriptions of content that overlaps with the content described with reference to FIG. 3 will be omitted.

Referring to FIG. 7, the active compensation device 100D can actively compensate for the noise current I _n input in common mode to each of the high current paths 111D, 112D, and 113D connected to the first device 300D.

To this end, the active compensation device (100D) according to another embodiment of the present invention includes three high current paths (111D, 112D, 113D), a sensing transformer (120D), a first amplifier (131D), and a second amplifier (132D). ), a first compensation transformer (140D) disposed on the output side of the first amplification unit (131D), a second compensation transformer (161D) and a compensation capacitor unit (162D) disposed on the output side of the second amplification unit (132D) may include.

In contrast to the active compensation device 100B according to the embodiment described in FIG. 3, the active compensation device 100D according to the embodiment shown in FIG. 7 includes three large current paths 111D, 112D, and 113D, Accordingly, there is a difference between the sensing transformer 120D, the first compensation transformer 140D, and the compensation capacitor unit 162D. Therefore, the following will describe the active compensation device (100D) focusing on the above-mentioned differences.

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

The primary side (121D) of the sensing transformer (120D) is disposed in each of the first large current path (111D), the second large current path (112D), and the third large current path (113D), and an induced voltage is applied to the secondary side (122D). V _sen can be generated. The magnetic flux density generated in the sensing transformer (120D) by the noise current I _n on the three large current paths (111D, 112D, and 113D) can be mutually reinforced.

Meanwhile, in the active compensation device 100D, the first and second amplification units 131D and 132D correspond to the amplification units 131B and 132B. For example, the secondary side (122D) wire of the sensing transformer (120D) may be connected in parallel to each of the first amplification unit (131D) and the second amplification unit (132D). The voltage V _sen induced in the secondary side (122D) of the sensing transformer (120D) becomes the input voltage of the first amplification unit (131D) and the second amplification unit (132D). The first amplification unit 131D may output an amplification voltage V ₁ based on the input voltage, and the second amplification unit 132D may output an amplification voltage V ₂ based on the input voltage.

The V ₁ may be the input voltage of the first compensation transformer 140D, that is, the voltage of the primary side 141D of the first compensation transformer 140D. The V ₂ may be the input voltage of the second compensation transformer 161D, that is, the primary side voltage of the second compensation transformer 161D.

Meanwhile, the secondary side 142D of the first compensation transformer 140D may be disposed in each of the first high current path 111D, the second high current path 112D, and the third high current path 113D. The first compensation transformer (140D) is based on the primary side (141D) voltage (V ₁ ) output from the first amplifier (131D), and three high current paths (111D, 112D, 111D, 112D, 113D) A compensation voltage V _inj1 can be generated in series for each.

Meanwhile, the second compensation transformer 161D and the compensation capacitor unit 162D are included in the second compensation unit 160D, and V ₂ , the output voltage of the second amplification unit 132D, is the input of the second compensation unit 160D. It may be the voltage, that is, the voltage of the primary side (141D) of the second compensation transformer (161D). The second compensation transformer 161D may generate an induced voltage V ₃ on the secondary side based on the primary side voltage V ₂ .

The secondary side of the second compensation transformer 161D may be placed on a path connecting the compensation capacitor unit 162D and the reference potential (reference potential 1) of the compensation device 100D.

The compensation capacitor unit 162D includes three Y-capacitors (Y-), one end of which is connected to the secondary side of the second compensation transformer 161D, and the other end of which is connected to each of the high current paths 111D, 112D, and 113D. capacitor, Y-cap).

The compensation capacitor unit 150D is supplied from each of the first large current path 111D, the second large current path 112D, and the third large current path 113D based on the secondary side induced voltage V ₃ of the second compensation transformer 161D. The compensation current I _c is drawn to the reference potential of 1.

The active compensation device 100D according to this embodiment can simultaneously perform voltage compensation and current compensation for common mode noise on the power line of a three-phase, three-wire power system.

Figure 8 schematically shows the configuration of a system including an active compensation device 100E according to another embodiment of the present invention. Hereinafter, descriptions of content that overlaps with the content described with reference to FIG. 3 will be omitted.

Referring to FIG. 7, the active compensation device 100E can actively compensate for the noise current I _n input in common mode to each of the high current paths 111E, 112E, 113E, and 114E connected to the first device 300E. .

To this end, the active compensation device (100E) according to an embodiment of the present invention includes four large current paths (111E, 112E, 113E, 114E), a sensing transformer (120E), a first amplifier (131E), and a second amplifier ( 132E), a first compensation transformer 140E disposed on the output side of the first amplifier 131E, a second compensation transformer 161E and a compensation capacitor portion 162E disposed on the output side of the second amplifier 132E. ) may include.

In contrast to the active compensation device 100B according to the embodiment described in FIG. 3, the active compensation device 100E according to the embodiment shown in FIG. 8 includes four large current paths 111E, 112E, 113E, and 114E. And, accordingly, there is a difference between the sensing transformer 120E, the first compensation transformer 140E, and the compensation capacitor unit 162E. Therefore, hereinafter, the active compensation device 100E will be described focusing on the above-mentioned differences.

The active compensation device 100E may include a first large current path 111E, a second large current path 112E, a third large current path 113E, and a fourth large current path 114E that are distinct from each other. According to one embodiment, the first large current path 111E is the R phase, the second large current path 112E is the S phase, the third large current path 113E is the T phase, and the fourth large current path 114E is the T phase. may be an N-phase power line. The noise current I _n may be input in common mode to each of the first, second, third, and fourth large current paths (111E, 112E, 113E, and 114E).

The primary side 121E of the sensing transformer 120E is disposed in each of the first large current path 111E, the second large current path 112E, the third large current path 113E, and the fourth large current path 114E, An induced voltage V _sen can be generated on the secondary side (122E). The magnetic flux density generated in the sensing transformer 120E by the noise current I _n on the four large current paths 111E, 112E, 113E, and 114E can be mutually reinforced.

Meanwhile, in the active compensation device 100E, the first and second amplification units 131E and 132E correspond to the amplification units 131B and 132B. For example, the secondary side (122E) wire of the sensing transformer (120E) may be connected in parallel to each of the first amplification unit (131E) and the second amplification unit (132E). The voltage V _sen induced in the secondary side 122E of the sensing transformer 120E becomes the input voltage of the first amplifier 131E and the second amplifier 132E. The first amplifier 131E may output an amplified voltage V ₁ based on the input voltage, and the second amplifier 132E may output an amplified voltage V ₂ based on the input voltage.

The V ₁ may be the input voltage of the first compensation transformer 140E, that is, the voltage of the primary side 141E of the first compensation transformer 140E. The V ₂ may be the input voltage of the second compensation transformer 161E, that is, the primary side voltage of the second compensation transformer 161E.

Meanwhile, the secondary side 142E of the first compensation transformer 140E includes a first large current path 111E, a second large current path 112E, a third large current path 113E, and a fourth large current path 114E, respectively. can be placed in The first compensation transformer 140E is based on the primary side (141E) voltage (V ₁ ) output from the first amplifier 131E, and four high current paths 111E, 112E, which are the secondary side 142E, 113E, 114E), a compensation voltage V _inj1 can be generated in series for each.

Meanwhile, the second compensation transformer 161E and the compensation capacitor unit 162E are included in the second compensation unit 160E, and V ₂ , the output voltage of the second amplification unit 132E, is the input of the second compensation unit 160E. It may be the voltage, that is, the voltage of the primary side (141E) of the second compensation transformer (161E). The second compensation transformer 161E may generate an induced voltage V ₃ on the secondary side based on the primary side voltage V ₂ .

The secondary side of the second compensation transformer 161E may be placed on a path connecting the compensation capacitor unit 162E and the reference potential (reference potential 1) of the compensation device 100E.

The compensation capacitor unit 162E includes four Y-capacitors ( Includes Y-capacitor, Y-cap).

The compensation capacitor unit 150E includes a first large current path _111E , a second large current path 112E, a third large current path 113E, and The compensation current I _c is drawn to the reference potential 1 from each of the fourth large current paths 114E.

The active compensation device 100E according to this embodiment can simultaneously perform voltage compensation and current compensation for common mode noise on the power line of a three-phase, four-wire power system.

Unlike the case where only the CM choke is used, the active compensation device according to various embodiments may have only a small increase in size or price even if it is used for high power.

In addition, the active compensation device according to various embodiments of the present invention has a structure that is electrically insulated from a high current path (e.g., a power line), so the elements included in the amplification unit 130 can be protected from electrical overstress (EOS). . For example, since the amplifier 130 according to various embodiments of the present invention is insulated from the power line, it can use DC low voltage (e.g., third device 400, within 48V) used in the control board. Therefore, the amplifier 130 does not require a separate power conversion circuit. In addition, the active compensation device according to various embodiments of the present invention is rated to configure the amplification unit 130, regardless of the reference potential (reference potential 1) of the power supply device (e.g., the second device 200). Elements with low voltage can be used.

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. Additionally, if there is no specific mention such as “essential,” “important,” etc., it may not be a necessary component for the application of the present invention.

Therefore, 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 are within the scope of the spirit of the present invention. It will be said to belong to

Claims (1)

In the active compensation device that actively compensates for noise occurring in common mode in each of at least two large current paths connected to the first device,
at least two high current paths for transmitting a large current supplied by a second device to the first device;
a sensing unit that senses the common mode noise current on the high current path and generates an output signal corresponding to the noise current;
an amplification unit that amplifies the output signal of the sensing unit to generate a first amplification voltage and a second amplification voltage;
a first compensation unit that generates a compensation voltage on the high current path based on the first amplification voltage; and
An active compensation device comprising; a second compensation unit that branches and draws compensation current from the large current path based on the second amplified voltage.