Filtering device, electronic device and vehicle

Abstract

The application discloses a filtering device, an electronic device and a vehicle, and relates to the technical field of filtering devices.

Description

Technical Field

[0001] This application relates to the field of filtering technology, and in particular to a filtering device, electronic equipment, and vehicle. Background Technology

[0002] In electronic circuit design, circuit structures are often incorporated to filter common-mode voltage signals in order to improve signal quality and ensure circuit performance. However, the circuit structures used for filtering common-mode voltage signals in related technologies usually need to be customized according to load characteristics, resulting in poor versatility and inconvenience in practical applications. Utility Model Content

[0003] This application provides a filtering device, electronic equipment, and vehicle.

[0004] This application provides a filtering device, which is connected to a device to be filtered. The filtering device includes a sampling module, an inverting amplification module, and a filtering module connected in sequence.

[0005] The sampling module is configured to acquire the common-mode voltage signal of the device to be filtered;

[0006] The inverting amplifier module is configured to invert and amplify the common-mode voltage signal to determine the first voltage signal.

[0007] The filtering module is configured to supply a compensation current that is inversely phase with the common-mode voltage signal to the device to be filtered, based on the first voltage signal.

[0008] Thus, in this embodiment, the common-mode voltage of the device to be filtered can be sampled by a sampling module, an inverting amplification module, and a filtering module connected sequentially in the filtering device. The sampled common-mode voltage is then inverted and amplified to obtain a first voltage signal. A compensation current, inverse of the common-mode voltage signal, is then supplied to the device to be filtered through the first voltage signal. This allows the common-mode voltage in the device to be filtered to be filtered out based on the compensation current, thereby ensuring the circuit signal quality and circuit performance in the device to be filtered. Furthermore, since the sampling, inversion, amplification, and compensation current generation are based on the sampled common-mode signal, the generation of the compensation current can be related to the common-mode signal itself. This avoids the situation where the generation of the compensation current is highly correlated with the electrical characteristics of the device to be filtered, and further avoids the situation where the filtering device is only applicable to common-mode voltage filtering of fixed models or types of equipment. This, to a certain extent, ensures the versatility of the filtering device and its convenience in practical applications.

[0009] In some embodiments of this application, the inverting amplifier module includes a current isolation unit and an inverting amplifier unit, and the sampling module, the current isolation unit, the inverting amplifier unit and the filtering module are connected in sequence;

[0010] The current isolation unit is configured to send a second voltage signal corresponding to the common-mode voltage signal to the inverting amplifier unit;

[0011] The inverting amplifier unit is configured to invert and amplify the second voltage signal to determine the first voltage signal.

[0012] Thus, in this embodiment, the inverting amplifier module can be composed of a current isolation unit and an inverting amplifier unit. The current isolation unit can isolate the current flow between the sampling module and the inverting amplifier unit, thereby avoiding interference from the output current of the sampling module when the inverting amplifier unit performs signal inversion and amplification, and thus ensuring the validity of the first voltage signal output by the inverting amplifier unit.

[0013] In some embodiments of this application, the filtering device includes a power supply module, one end of the current isolation unit and one end of the inverting amplifier unit are both connected to the power supply module, and the other end of the current isolation unit and the other end of the inverting amplifier unit are both grounded;

[0014] The power supply module is configured to supply power to the current isolation unit and the inverting amplifier unit.

[0015] Thus, in this embodiment, the inverting amplifier module can be implemented based on a single-sided power supply current isolation unit and an inverting amplifier unit, thereby reducing the overall design difficulty of the filtering device to a certain extent.

[0016] In some embodiments of this application, the current isolation unit includes a first resistor, a second resistor, a third resistor, and a transistor. The power supply module is connected to the base of the transistor through the first resistor. One end of the second resistor is connected to the base, and the other end of the second resistor is grounded. The emitter of the transistor is grounded through the third resistor. The sampling module is connected to the base, and the emitter is connected to the inverting amplifier unit.

[0017] Thus, in this embodiment of the application, the current isolation unit can be composed of a first resistor, a second resistor, a third resistor, and a transistor.

[0018] In some embodiments of this application, the current isolation unit includes a first operational amplifier, which includes a first input terminal, a second input terminal, and a first output terminal. The sampling module is connected to the first input terminal, the second input terminal is connected to the first output terminal, and the first output terminal is connected to the inverting amplifier unit.

[0019] Thus, in this embodiment of the application, the current isolation unit can be implemented based on the first operational amplifier.

[0020] In some embodiments of this application, the inverting amplifier unit includes a first impedance network, a second operational amplifier, and a second impedance network. The second operational amplifier includes a third input terminal, a fourth input terminal, and a second output terminal. The current isolation unit is connected to one end of the first impedance network, and the other end of the first impedance network is connected to the third input terminal. The fourth input terminal is connected to a reference voltage. The second output terminal is connected to the filter module and one end of the second impedance network. The other end of the second impedance network is connected to the third input terminal. The reference voltage is half of the target voltage provided by the power supply module.

[0021] Thus, in this embodiment of the application, the inverting amplifier unit can be constructed based on a first impedance network, a second operational amplifier, and a second impedance network.

[0022] In some embodiments of this application, the inverting amplifier unit includes a third impedance network and a third operational amplifier. The third operational amplifier includes a fifth input terminal, a sixth input terminal, and a third output terminal. The current isolation unit is connected to one end of the third impedance network, and the other end of the third impedance network is connected to the fifth input terminal. The sixth input terminal is connected to a reference voltage, and the third output terminal is connected to the filter module. The reference voltage is half of the target voltage provided by the power supply module.

[0023] Thus, in this embodiment of the application, the inverting amplifier unit can be constructed based on a third impedance network and a third operational amplifier.

[0024] In some embodiments of this application, the filtering module includes a first isolation capacitor, and the inverting amplifier module, the first isolation capacitor, and the device to be filtered are connected in sequence.

[0025] The first isolation capacitor is configured to supply the compensation current to the device to be filtered according to the first voltage signal.

[0026] Thus, in this embodiment of the application, the filtering module can be implemented through the first isolation capacitor, thereby reducing the design difficulty and cost of the filtering model and filtering device to a certain extent.

[0027] In some embodiments of this application, the filtering module includes a current amplification unit and a second isolation capacitor, and the inverting amplification module, the current amplification unit, the second isolation capacitor and the device to be filtered are connected in sequence;

[0028] The current amplification unit is configured to amplify the first current corresponding to the first voltage signal to determine the second current;

[0029] The second isolation capacitor is configured to supply a compensation current that is inversely phase to the common-mode voltage signal to the device to be filtered, based on the second current.

[0030] Thus, in this embodiment, the filter module can be composed of a current amplification unit and a second isolation capacitor, which can, to a certain extent, avoid the situation where the compensation current supplied by the filter module is too small and therefore cannot effectively offset the common-mode voltage signal in the device to be filtered. This can, to a certain extent, ensure the effectiveness and reliability of the compensation current supplied by the filter module.

[0031] In some embodiments of this application, the filtering device includes a power supply module, one end of the current amplification unit is connected to the power supply module, and the other end of the current amplification unit is grounded;

[0032] The power supply module is configured to supply power to the current amplification unit.

[0033] Thus, in this embodiment of the application, the filtering module can be implemented based on a current amplification unit with a single-sided power supply, thereby reducing the design difficulty of the filtering module and the filtering device to a certain extent.

[0034] In some embodiments of this application, the current amplification unit includes a first transistor and a second transistor. The power supply module is connected to the collector of the first transistor, the emitter of the first transistor is connected to the collector of the second transistor, the emitter of the second transistor is grounded, the inverting amplification module is connected to the base of the first transistor and the base of the second transistor, and the connection point between the first transistor and the second transistor is connected to the second isolation capacitor.

[0035] Thus, in this embodiment of the application, the current amplification unit can be implemented by a first transistor and a second transistor.

[0036] In some embodiments of this application, the current amplification unit includes a third transistor, a fourth transistor, a fourth impedance network, a fifth impedance network, and a sixth impedance network. The inverting amplification module is connected to one end of the fourth impedance network, one end of the fifth impedance network, and one end of the sixth impedance network. The other end of the fourth impedance network is connected to the base of the third transistor. The other end of the fifth impedance network is connected to the junction point of the third and fourth transistors. The other end of the sixth impedance network is connected to the base of the fourth transistor. The junction point is connected to the second isolation capacitor. The emitter of the fourth transistor is grounded.

[0037] Thus, in this embodiment, the current amplification module can be implemented by a current amplification unit including a third transistor, a fourth transistor, a fourth impedance network, a fifth impedance network, and a sixth impedance network.

[0038] In some embodiments of this application, the inverting amplifier module includes a third operational amplifier and a seventh impedance network. The third operational amplifier includes a fifth input terminal and a third output terminal, and the third output terminal, the fifth impedance network, the seventh impedance network, and the fifth input terminal are connected in sequence.

[0039] Thus, in this embodiment of the application, a feedback loop for the third operational amplifier can be formed by sequentially connecting the third output terminal, the fifth impedance network, the seventh impedance network, and the fifth input terminal, thereby ensuring the robust processing of voltage signals by the third operational amplifier to a certain extent.

[0040] In some embodiments of this application, the filtering module includes a plurality of current amplification units arranged in parallel.

[0041] Thus, in this embodiment, multiple current amplification units can be arranged in parallel in the filtering module, thereby ensuring that the compensation capability of the filtering module meets the common-mode voltage cancellation requirements.

[0042] In some embodiments of this application, the filtering device includes a power supply module configured to provide a target voltage to the inverting amplifier module and the filtering module;

[0043] The sampling module is configured to perform DC component boosting processing on the common-mode voltage signal based on a reference voltage to determine the processed voltage signal, wherein the reference voltage is half of the target voltage provided by the power supply module.

[0044] The inverting amplifier module is configured to invert and amplify the processed voltage signal to determine the first voltage signal.

[0045] Thus, in this embodiment, the sampling module can perform DC component boosting processing on the common-mode voltage signal based on the reference voltage to determine the processed voltage signal, and the inverting amplifier module can perform inversion and amplification processing on the processed voltage signal to determine the first voltage signal. This allows each module in the filter device to be configured to be powered by a single-sided positive voltage, thereby reducing the design difficulty and cost of the filter device.

[0046] In some embodiments of this application, the filtering device includes a third isolation capacitor, and the device to be filtered, the third isolation capacitor, and the sampling module are connected in sequence.

[0047] Thus, in this embodiment of the application, the device to be filtered, the third isolation capacitor, and the sampling module can be connected in sequence to ensure the robust operation of the sampling module.

[0048] This application provides an electronic device that includes the filtering device described above.

[0049] This application provides a vehicle that includes the above-described filtering device or the above-described electronic device.

[0050] The electronic device and vehicle provided in this application can sample the common-mode voltage of the device to be filtered through a sampling module, an inverting amplification module, and a filtering module connected in sequence in the filtering device. The sampled common-mode voltage is then inverted and amplified to obtain a first voltage signal. A compensation current, inverted from the common-mode voltage signal, is then supplied to the device to be filtered through the first voltage signal. This allows the common-mode voltage in the device to be filtered to be filtered out based on the compensation current, thereby ensuring the circuit signal quality and circuit performance in the device to be filtered. Furthermore, since the sampling, inversion, amplification, and compensation current generation are based on the sampled common-mode signal, the generation of the compensation current can be related to the common-mode signal itself. This avoids the situation where the generation of the compensation current is highly correlated with the electrical characteristics of the device to be filtered, and further avoids the situation where the filtering device is only applicable to common-mode voltage filtering of fixed models or types of equipment. This, to a certain extent, ensures the versatility of the filtering device and its convenience in practical applications.

[0051] Additional aspects and advantages of embodiments of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of embodiments of this application. Attached Figure Description

[0052] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, wherein:

[0053] Figure 1 This is a schematic diagram of a filtering device in some embodiments of this application;

[0054] Figure 2 This is a schematic diagram of a filtering device in some embodiments of this application;

[0055] Figure 3 This is a schematic diagram of a filtering device in some embodiments of this application;

[0056] Figure 4 This is a schematic diagram of a filtering device in some embodiments of this application;

[0057] Figure 5 This is a schematic diagram of a filtering device in some embodiments of this application;

[0058] Figure 6 This is a schematic diagram of a filtering device in some embodiments of this application;

[0059] Figure 7 This is a schematic diagram of a filtering device in some embodiments of this application;

[0060] Figure 8 This is a schematic diagram illustrating application scenarios in some embodiments of this application;

[0061] Figure 9 This is a schematic diagram illustrating application scenarios in some embodiments of this application;

[0062] Figure 10 This is a schematic diagram illustrating application scenarios in some embodiments of this application;

[0063] Figure 11 This is a schematic diagram illustrating application scenarios in some embodiments of this application. Detailed Implementation

[0064] The embodiments of this application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the embodiments of this application, and should not be construed as limiting the embodiments of this application.

[0065] In an active filter circuit proposed in related technologies, the common-mode current generated by the motor load can be actively drawn out in advance, thereby preventing the common-mode current from reaching the LISN (Line Impedance Stabilization Network) detector and VDC (Voltage Direct Current), thus achieving the purpose of suppressing the conduction of common-mode noise to the external power supply.

[0066] Specifically, the active filter circuit includes voltage division sampling of the three-phase voltage noise using three resistors R0, R1, and R2. Simultaneously, it samples the noise voltage at the voltage neutral point and uses an amplifier U1 to follow the noise voltage while isolating the current, preventing the impedance of subsequent circuits from affecting the voltage division sampling accuracy. Therefore, based on the sampling and voltage division using R0, R1, R2, and U1, the expression Vin = Vcm * R2 / (R1 + R2 + R0 / 3) can be obtained, where Vcm is the actual common-mode voltage signal. Then, the control amplifier U2 provides a small current to the base of the transistor in the current amplification stage, thereby driving the current amplification stage to generate a large constant current. The magnitude of this constant current determines the maximum amplitude that Icomp can achieve. Finally, the current Icomp is injected into the three-phase motor load through the isolation capacitor C1 and resistor R4 to filter out the common-mode voltage.

[0067] However, this active filter circuit has the following drawbacks:

[0068] (1) High power consumption and severe heat generation hinder the improvement of current compensation capability. Specifically, there is a constant current in the transistor path of the current amplification stage. In order to ensure that the generated compensation current Icomp is not distorted, this constant current must be greater than or equal to the maximum amplitude of the compensation current. Therefore, the power consumption generated by this path is inevitably large. Furthermore, when the power consumption is large, it is usually accompanied by severe heat generation. Electronic devices usually have upper limits on heat generation and power consumption, which limits the improvement of current level. It is understandable that in automotive electronic control, the peak common-mode current can reach several amperes, so it is clear that this active filter circuit is difficult to meet this level requirement.

[0069] (2) The circuit has poor versatility and requires specific circuit matching for the load impedance. Specifically, the circuit principle of this active filter circuit determines that the load impedance simulation circuit is matched with a specific motor load. This means that every time the load application object is changed, it needs to be rematched, which is inconvenient in practical applications. Moreover, even for the same model of motor, there is a certain impedance difference between each sample, which will also cause compensation error.

[0070] (3) Negative voltage power supply is costly. Specifically, both amplifiers and current amplification stages require negative voltage power supply, which necessitates the use of specialized negative voltage power supply chips. However, there are currently no negative voltage applications in automotive electronic control products. The addition of negative voltage power supply means an increase in cost, and the application of negative voltage power supply is generally not as convenient as single-sided positive voltage power supply.

[0071] (4) Insufficient high-voltage safety. Specifically, this active filter circuit is only suitable for common-mode filtering of low-voltage motors. There is no capacitor isolation between the three phases of the motor and the active filter low-voltage function circuit, so it is not suitable for high-voltage applications.

[0072] Based on the issues mentioned above, please refer to Figure 1 This application provides a filtering device 1000, which is connected to a device 2000 to be filtered. The filtering device 1000 includes a sampling module 1100, an inverting amplifier module 1200, and a filtering module 1300 connected in sequence. The sampling module 1100 is configured to collect the common-mode voltage signal of the device 2000 to be filtered. The inverting amplifier module 1200 is configured to invert and amplify the common-mode voltage signal to determine a first voltage signal. The filtering module 1300 is configured to supply a compensation current that is inverted from the common-mode voltage signal to the device 2000 to be filtered according to the first voltage signal.

[0073] Specifically, this application provides a method for reducing the common-mode voltage by sampling the common-mode voltage, inverting and amplifying the common-mode voltage, and injecting an inverted compensation current into the device to be filtered 2000 caused by the inverted amplified voltage, thereby suppressing (or canceling) the common-mode noise current in the device to be filtered 2000. Specifically, this application provides a filtering device 1000, which, after being connected to the device to be filtered 2000 (such as a vehicle's motor controller, power supply, etc.), injects a compensation current inversely phase to the common-mode voltage into the device to be filtered 2000 through a sampling module 1100, an inverting amplification module 1200, and a filtering module 1300 connected sequentially within the device, thereby suppressing (or canceling) the common-mode signal in the filtering device.

[0074] The sampling module 1100 is used to collect the common-mode voltage signal in the filter device 2000 and send the collected common-mode voltage signal to the inverting amplifier module 1200.

[0075] Furthermore, when the inverting amplifier module 1200 receives the common-mode voltage signal sent by the sampling module 1100, it can invert (i.e., flip the phase by 180°) and amplify (e.g., amplify the signal amplitude) the common-mode voltage signal, thereby obtaining a first voltage signal that is greater than the "common-mode voltage signal sent by the sampling module 1100" and is inverted from the "common-mode voltage signal sent by the sampling module 1100".

[0076] Furthermore, the inverting amplifier module 1200 can send the first voltage signal to the filtering module 1300 when generating the first voltage signal. Upon receiving the first voltage signal, the filtering module 1300 can generate a filter current corresponding to the first voltage signal and inversely phase to the common-mode voltage signal sent by the sampling module 1100, and inject the filter current into the device to be filtered 2000, thereby suppressing the common-mode voltage signal in the device to be filtered 2000.

[0077] Thus, in this embodiment of the application, the common-mode voltage of the device to be filtered 2000 can be sampled by the sampling module 1100, the inverting amplifier module 1200 and the filtering module 1300 connected in sequence in the filtering device 1000. The sampled common-mode voltage is then inverted and amplified to obtain a first voltage signal. A compensation current that is inversely phased with the common-mode voltage signal is then sent to the device to be filtered 2000 through the first voltage signal. This allows the common-mode voltage in the device to be filtered 2000 to be filtered to be filtered out based on the compensation current, thereby ensuring the circuit signal quality and circuit performance in the device to be filtered 2000. Furthermore, since the sampling, inversion, amplification, and compensation current generation are performed based on the sampled common-mode signal, the generation of the compensation current can be related to the common-mode signal itself. This avoids the situation where the generation of the compensation current is highly correlated with the electrical characteristics of the device to be filtered 2000 itself. Consequently, it avoids the situation where the filter device 1000 can only be used for common-mode voltage filtering of fixed models or types of equipment. This can ensure the versatility of the filter device 1000 to a certain extent, and thus ensure the convenience of the filter device 1000 in practical applications.

[0078] It is understood that in this embodiment of the application, the common-mode signal acquired and output by the sampling module 1100 has a low amplitude. Therefore, this embodiment of the application is provided with an inverting amplifier module 1200 for performing voltage signal inversion and amplification, so as to ensure that the amplitude of the voltage signal is high enough so that the filtering module 1300 can generate a sufficiently large compensation current while generating a voltage signal that is inversely phase to the common-mode voltage signal sent by the sampling module 1100.

[0079] In one example, the sampling module 1100 is constructed based on a resistor voltage divider circuit for sampling current. In another example, a resistor-capacitor composite circuit is used for sampling.

[0080] In one example, in addition to the functions of voltage signal inversion and voltage signal amplification, the inverting amplifier module 1200 also has the function of current isolation. In other words, in order to avoid the influence of the current from the sampling module 1100 on the inverting amplifier module 1200 itself and other subsequent modules, the inverting amplifier module 1200 can only receive or acquire the voltage signal (i.e., common-mode voltage signal) from the sampling module 1100, thereby avoiding current interference.

[0081] In one example, the filter module 1300 is a capacitor. When the first voltage signal sent by the inverting amplifier module 1200 is received on one side of the capacitor, a voltage difference is formed on both sides of the capacitor, thereby causing current to flow. This forms a compensation current that is inverse of the common-mode voltage signal sent by the sampling module 1100 and is sent to the filter device 2000.

[0082] Please see Figure 2In some embodiments of this application, the inverting amplifier module 1200 includes a current isolation unit 1210 and an inverting amplifier unit 1220. The sampling module 1100, the current isolation unit 1210, the inverting amplifier unit 1220 and the filtering module 1300 are connected in sequence. The current isolation unit 1210 is configured to send a second voltage signal corresponding to the common-mode voltage signal to the inverting amplifier unit 1220. The inverting amplifier unit 1220 is configured to invert and amplify the second voltage signal to determine the first voltage signal.

[0083] Specifically, in this embodiment of the application, the inverting amplifier module 1200 may be composed of two units: a current isolation unit 1210 and an inverting amplifier unit 1220.

[0084] Understandably, the noise in the input signal of the inverting amplifier unit 1220 should be as low as possible, so as to avoid the inverting amplifier unit 1220 amplifying and outputting the noise as much as possible.

[0085] For example, if the common-mode voltage in the device to be filtered 2000 contains 50Hz power frequency interference, and if the sampling module 1100 outputs the sampled voltage signal to the inverting amplifier module 1200, the inverting amplifier unit 1220 can amplify the 50Hz power frequency interference, which may cause a corresponding resonance problem after the filtering module 1300 injects compensation current into the device to be filtered 2000.

[0086] Therefore, in this embodiment, a current isolation unit 1210 can be set to achieve electrical isolation between the sampling module 1100 and the inverting amplifier unit 1220, such as isolating the current flow between the sampling module 1100 and the inverting amplifier unit 1220, thereby avoiding loop self-excitation or interference coupling, thus achieving equivalent transmission of voltage signals, and further avoiding the impact of the impedance of subsequent circuits on sampling accuracy.

[0087] Furthermore, the inverting amplifier unit 1220 is used to invert (i.e., flip the phase by 180°) and amplify (e.g., amplify the signal amplitude) the received voltage input signal (i.e., the second voltage signal), thereby obtaining a voltage output signal that is greater than the "voltage input signal" and is inverted from the "voltage input signal", which is the aforementioned second voltage signal.

[0088] Thus, in this embodiment, the inverting amplifier module 1200 can be composed of a current isolation unit 1210 and an inverting amplifier unit 1220. The current isolation unit 1210 can isolate the current flow between the sampling module 1100 and the inverting amplifier unit 1220, thereby avoiding interference from the output current of the sampling module 1100 when the inverting amplifier unit 1220 performs signal inversion and amplification, and thus ensuring the validity of the first voltage signal output by the inverting amplifier unit 1220.

[0089] Please refer to it again. Figure 2 In some embodiments of this application, the filter device 1000 includes a power supply module 1400. One end of the current isolation unit 1210 and one end of the inverting amplifier unit 1220 are both connected to the power supply module 1400. The other end of the current isolation unit 1210 and the other end of the inverting amplifier unit 1220 are both grounded. The power supply module 1400 is configured to supply power to the current isolation unit 1210 and the inverting amplifier unit 1220.

[0090] Specifically, in the embodiments of this application, the current isolation unit 1210 and the inverting amplifier unit 1220 are both active devices, thereby ensuring effective isolation of the common-mode voltage signal transmitted by the sampling module 1100 and ensuring robustness when inverting and amplifying the second voltage signal.

[0091] Meanwhile, to reduce the overall design difficulty of the filter device 1000, one end of the current isolation unit 1210 and one end of the inverting amplifier unit 1220 are connected to the power supply module 1400, and the other end of the current isolation unit 1210 and the other end of the inverting amplifier unit 1220 are grounded. In other words, the current isolation unit 1210 and the inverting amplifier unit 1220 are both powered on one side. Compared with the case of dual-sided power supply, the design difficulty of the filter device 1000 is relatively low.

[0092] In one example, to further reduce the design difficulty and cost of the filter device 1000, both the current isolation unit 1210 and the inverting amplifier unit 1220 are powered by a single-sided positive voltage.

[0093] Thus, in this embodiment of the application, the inverting amplifier module 1200 can be implemented based on the single-sided power supply current isolation unit 1210 and the inverting amplifier unit 1220, thereby reducing the overall design difficulty of the filter device 1000 to a certain extent.

[0094] Please refer to the following: Figure 2 and Figure 3 In some embodiments of this application, the current isolation unit 1210 includes a first resistor 1211, a second resistor 1212, a third resistor 1213, and a transistor 1214. The power supply module 1400 is connected to the base of the transistor 1214 through the first resistor 1211. One end of the second resistor 1212 is connected to the base, and the other end of the second resistor 1212 is grounded. The emitter of the transistor 1214 is grounded through the third resistor 1213. The sampling module 1100 is connected to the base, and the emitter is connected to the inverting amplifier unit 1220.

[0095] Specifically, in this embodiment, the current isolation unit 1210 may be composed of a first resistor 1211, a second resistor 1212, a third resistor 1213, and a transistor 1214. Specifically, the power supply module 1400 is connected to the base of the transistor 1214 via the first resistor 1211. One end of the second resistor 1212 is connected to the base of the transistor 1214, while the other end of the second resistor 1212 is grounded, thereby forming a voltage divider bias circuit. Furthermore, the emitter of the transistor 1214 is connected to one end of the third resistor 1213, while the other end of the third resistor 1213 is grounded. It is understood that the input signal (such as the common-mode voltage signal sent by the sampling module 1100) is connected to the base, and the output signal (such as the second voltage signal) is led out from the emitter via the third resistor 1213.

[0096] Among them, the first resistor 1211, the second resistor 1212, and the third resistor 1213 can be used in conjunction with the target voltage output by the power supply module 1400 (i.e., Figure 4 The common-mode voltage signal sampled and output by the sampling module 1100 is applied to the base of the transistor 1214, and the emitter voltage follows the change of the base voltage (emitter junction forward bias).

[0097] Furthermore, due to the base current I B Much smaller than the emitter current I E Therefore, the input current almost does not flow directly into the output side, thus achieving current isolation. At the same time, the emitter voltage closely follows the base voltage, completing the equivalent transmission of the voltage signal and avoiding the influence of subsequent circuit impedance on sampling accuracy.

[0098] In one example, the base current I B Much smaller than the emitter current I E The relationship between them can be shown in the following formula:

[0099] I E =(1+β)I B

[0100] In the formula, β is the current amplification factor.

[0101] Thus, in this embodiment of the application, the current isolation unit 1210 can be composed of a first resistor 1211, a second resistor 1212, a third resistor 1213 and a transistor 1214.

[0102] Please refer to the following: Figure 2 and Figure 4In some embodiments of this application, the current isolation unit 1210 includes a first operational amplifier 1215, which includes a first input terminal, a second input terminal, and a first output terminal. The sampling module 1100 is connected to the first input terminal, the second input terminal is connected to the first output terminal, and the first output terminal is connected to the inverting amplifier unit 1220.

[0103] Specifically, in this embodiment, the current isolation unit 1210 can be implemented by a first operational amplifier 1215. Specifically, the first operational amplifier 1215 is powered by a power supply module 1400 (i.e., Figure 4 The input signal (such as the common-mode voltage signal sent by the sampling module 1100) is connected to the first input terminal of the first operational amplifier 1215, and the first output terminal of the first operational amplifier 1215 is connected to the second input terminal of the first operational amplifier 1215, thereby forming a voltage follower structure.

[0104] Understandably, the first operational amplifier 1215 has extremely high input impedance and extremely low output impedance. Therefore, the high input impedance makes the current flowing into the first operational amplifier 1215 along the first input terminal approximately zero, thus not affecting the current distribution of the preceding sampling circuit and achieving current isolation. And, the output voltage V... out Closely follow the input voltage V in The low output impedance ensures stable voltage signal transmission, thereby blocking current while transmitting the voltage signal to subsequent circuits without distortion, thus ensuring sampling accuracy.

[0105] In one example, the first input terminal of the first operational amplifier 1215 is a positive input terminal (+), and the second input terminal of the first operational amplifier 1215 is a negative input terminal (-).

[0106] Thus, in this embodiment of the application, the current isolation unit 1210 can be implemented based on the first operational amplifier 1215.

[0107] Please refer to the following: Figure 2 and Figure 5 In some embodiments of this application, the inverting amplifier unit 1220 includes a first impedance network 1221, a second operational amplifier 1222, and a second impedance network 1223. The second operational amplifier 1222 includes a third input terminal, a fourth input terminal, and a second output terminal. The current isolation unit 1210 is connected to one end of the first impedance network 1221, and the other end of the first impedance network 1221 is connected to the third input terminal. The fourth input terminal is connected to a reference voltage. The second output terminal is connected to the filter module 1300 and one end of the second impedance network 1223. The other end of the second impedance network 1223 is connected to the third input terminal. The reference voltage is half of the target voltage provided by the power supply module 1400.

[0108] Specifically, in this embodiment, the inverting amplifier unit 1220 may be composed of a first impedance network 1221, a second operational amplifier 1222, and a second impedance network 1223. The current isolation unit 1210 is connected to one end of the first impedance network 1221, the other end of the first impedance network 1221 is connected to the third input terminal of the second operational amplifier 1222, the fourth input terminal of the second operational amplifier 1222 is connected to a reference voltage Vref, the second output terminal of the second operational amplifier 1222 is connected to the filter module 1300 and one end of the second impedance network 1223, and the other end of the second impedance network 1223 is connected to the third input terminal of the second operational amplifier 1222.

[0109] The second operational amplifier 1222 processes the first voltage signal sent by the current isolation unit 1210 based on the reference voltage Vref. Specifically, based on the parameters (such as the resistance ratio) set by the first impedance network 1221 and the second impedance network 1223 respectively, the second operational amplifier 1222 amplifies the first voltage signal sent by the current isolation unit 1210 in reverse phase.

[0110] As an example, for the AC component containing common-mode noise in the first voltage signal sent by the current isolation unit 1210, the second operational amplifier 1222 can process the AC component, causing its phase to be reversed and its amplitude to be amplified by a set gain. Furthermore, for the DC component in the first voltage signal sent by the current isolation unit 1210, the DC component maintains a steady state based on a reference voltage Vref. Therefore, the voltage signal output along the second output terminal of the second operational amplifier 1222 is (Vref - A × ΔV), which can then provide a sufficient voltage drive signal for the filter module 1300, where A is the amplification factor and ΔV is the AC component containing common-mode noise.

[0111] It is understandable that the purpose of connecting the second input terminal of the second operational amplifier 1222 to the reference voltage Vref is to cancel the magnitude of the DC component of the "first voltage signal sent by the current isolation unit 1210", avoid a large change in the amplitude of the DC component of the amplified output signal, and make the magnitude of the DC component of the amplified output signal the same as or similar to the magnitude of the DC component of the "first voltage signal sent by the current isolation unit 1210".

[0112] It is also understood that, in the embodiments of this application, the specific structures of the first impedance network 1221 and the second impedance network 1223 can be set according to the actual situation, such as any network composed of a capacitor and at least one resistor.

[0113] Furthermore, it is understandable that half of the target voltage Vcc of the power supply module 1400 (i.e., the reference voltage Vref) can be considered as the midpoint of the single-sided positive voltage supply range. Therefore, setting the signal reference to the midpoint allows the AC component to achieve maximum symmetrical fluctuation within the positive voltage range, thereby fully utilizing the dynamic range of the supply voltage. Moreover, if the reference voltage Vref is greater than or equal to half of the target voltage, it may cause the signal to bias towards the positive or negative voltage side, compressing the effective fluctuation range, and even requiring adjustments to the threshold design of subsequent modules.

[0114] In one example, the third input of the second operational amplifier 1222 is a positive input (+), and the fourth input of the second operational amplifier 1222 is a negative input (-).

[0115] In addition, it is understandable that Figure 5 Vcc in the figure represents the target voltage provided by the power supply module 1400 to the second operational amplifier 1222.

[0116] Thus, in this embodiment of the application, the inverting amplifier unit 1220 can be constructed based on the first impedance network 1221, the second operational amplifier 1222, and the second impedance network 1223.

[0117] Please refer to the following: Figure 2 and Figure 6 In some embodiments of this application, the inverting amplifier unit 1220 includes a third impedance network 1224 and a third operational amplifier 1225. The third operational amplifier 1225 includes a fifth input terminal, a sixth input terminal, and a third output terminal. The current isolation unit 1210 is connected to one end of the third impedance network 1224, and the other end of the third impedance network 1224 is connected to the fifth input terminal. The sixth input terminal is connected to a reference voltage, and the third output terminal is connected to the filter module 1300. The reference voltage is half of the target voltage provided by the power supply module 1400.

[0118] Specifically, in this embodiment, the inverting amplifier unit 1220 can be implemented by a third impedance network 1224 and a third operational amplifier 1225. Specifically, the second voltage signal output from the current isolation unit 1210 is connected to the third impedance network 1224. After being processed by the third impedance network 1224, the second voltage signal enters the third operational amplifier 1225 through its fifth input terminal. The sixth input terminal of the third operational amplifier 1225 is connected to a reference voltage Vref. Simultaneously, the third operational amplifier 1225 receives the target voltage Vcc provided by the power supply module 1400.

[0119] Furthermore, after the second voltage signal output by the current isolation unit 1210 is processed by the third impedance network 1224, the processed voltage signal enters the third operational amplifier 1225 through the fifth input terminal of the third operational amplifier 1225. Next, the AC component of the processed voltage signal is amplified by the third operational amplifier 1225 and its phase is inverted, while the DC component of the processed voltage signal remains steady with reference voltage Vref as a reference. Finally, based on the parameters set by the impedance network (such as the resistance ratio), the signal amplification factor is determined so that the final output signal (i.e., the first voltage signal) is (Vref - A × ΔV), thereby providing sufficient voltage drive signal for the filter module 1300, where A is the amplification factor and ΔV is the AC component containing common-mode noise.

[0120] It is understandable that the purpose of connecting the reference voltage Vref to the sixth input terminal of the third operational amplifier 1225 is to cancel the magnitude of the DC component of the "first voltage signal sent by the current isolation unit 1210", to avoid a large change in the amplitude of the DC component of the amplified output signal, and to make the magnitude of the DC component of the amplified output signal the same as or similar to the magnitude of the DC component of the "first voltage signal sent by the current isolation unit 1210".

[0121] It is also understood that, in the embodiments of this application, the specific structure of the third impedance network 1224 can be set according to the actual situation, such as any network composed of a capacitor and at least one resistor.

[0122] Furthermore, it is understandable that half of the target voltage Vcc of the power supply module 1400 (i.e., the reference voltage Vref) can be considered as the midpoint of the single-sided positive voltage supply range. Therefore, setting the signal reference to the midpoint allows the AC component to achieve maximum symmetrical fluctuation within the positive voltage range, thereby fully utilizing the dynamic range of the supply voltage. Moreover, if the reference voltage Vref is greater than or equal to half of the target voltage, it may cause the signal to bias towards the positive or negative voltage side, compressing the effective fluctuation range, and even requiring adjustments to the threshold design of subsequent modules.

[0123] In one example, the fifth input of the third operational amplifier 1225 is a positive input (+), and the sixth input of the second operational amplifier 1222 is a negative input (-).

[0124] In addition, it is understandable that Figure 6 Vcc in the figure represents the target voltage Vcc provided by the power supply module 1400 to the third operational amplifier 1225.

[0125] Thus, in this embodiment of the application, the inverting amplifier unit 1220 can be constructed based on the third impedance network 1224 and the third operational amplifier 1225.

[0126] In some embodiments of this application, the filtering module 1300 includes a first isolation capacitor, and the inverting amplifier module 1200, the first isolation capacitor and the device to be filtered 2000 are connected in sequence. The first isolation capacitor is configured to supply a compensation current to the device to be filtered 2000 according to a first voltage signal.

[0127] Specifically, in this embodiment, the filtering module 1300 can be implemented by a capacitor that provides voltage isolation, i.e., by a first isolation capacitor. It is understood that when the first voltage signal sent by the inverting amplifier module 1200 is received on one side of the first isolation capacitor, a voltage difference is formed across the first isolation capacitor, causing current to flow. This forms a compensation current that is inversely phase to the common-mode voltage signal sent by the sampling module 1100 and is transmitted to the device to be filtered 2000, thereby filtering out (or suppressing) the common-mode voltage signal in the device to be filtered 2000.

[0128] Thus, in this embodiment of the application, the filtering module 1300 can be implemented through the first isolation capacitor, thereby reducing the design difficulty and cost of the filtering model and the filtering device 1000 to a certain extent.

[0129] Please refer to it again. Figure 2 In some embodiments of this application, the filtering module 1300 includes a current amplification unit 1310 and a second isolation capacitor 1320. The inverting amplification module 1200, the current amplification unit 1310, the second isolation capacitor 1320 and the device to be filtered 2000 are connected in sequence. The current amplification unit 1310 is configured to amplify the first current corresponding to the first voltage signal to determine the second current. The second isolation capacitor 1320 is configured to supply a compensation current that is inversely phase to the common-mode voltage signal to the device to be filtered 2000 according to the second current.

[0130] Specifically, to avoid the compensation current supplied to the filtering device 2000 being too small to effectively cancel (or suppress) the common-mode voltage signal in the filtering device 2000, in this embodiment of the application, the filtering module 1300 may be composed of a current amplification unit 1310 and a second isolation capacitor 1320. The current amplification unit 1310 can amplify the driving current (i.e., the first current) output by the inverting amplification module 1200 in terms of amplitude, thereby ensuring that the second isolation capacitor 1320 can generate a compensation current of sufficient strength.

[0131] It is understandable that the voltage signal output by the inverting amplifier module 1200 contains a drive current signal (i.e., the first current) that is inversely phase to the common-mode noise. It is also understandable that when the second current sent by the current amplification unit 1310 is received on one side of the second isolation capacitor 1320, a voltage difference is formed across the second isolation capacitor 1320, causing current flow. This results in a compensation current that is inversely phase to the common-mode voltage signal sent by the sampling module 1100 and is sent to the filtering device 2000, thereby filtering out (or suppressing) the common-mode voltage signal in the filtering device 2000.

[0132] It is also understood that the number of second isolation capacitors 1320 can be set according to actual needs. For example, when the number of second isolation capacitors 1320 is greater than 2, one end of each second isolation capacitor 1320 can be connected in parallel to the inverting amplifier module 1200, and the other end of each second isolation capacitor 1320 can be connected to the same or different positions in the filter device 2000.

[0133] It is understandable that if the input terminal of the filter device and the other end (i.e., the output terminal) of each of the second isolation capacitors 1320 are at the same location in the device to be filtered 2000, a closed-loop negative feedback is formed. It is also understandable that if the input terminal of the filter device and the other end (i.e., the output terminal) of each of the second isolation capacitors 1320 are at different locations in the device to be filtered 2000, it is necessary to confirm whether the formed negative feedback is reasonable.

[0134] Thus, in this embodiment, the filter module 1300 can be composed of a current amplification unit 1310 and a second isolation capacitor 1320, which can, to a certain extent, avoid the situation where the compensation current supplied by the filter module 1300 is too small and therefore cannot effectively offset the common-mode voltage signal in the device to be filtered 2000. This can, to a certain extent, ensure the effectiveness and reliability of the compensation current supplied by the filter module 1300.

[0135] Please refer to it again. Figure 2 In some embodiments of this application, the filter device 1000 includes a power supply module 1400, one end of the current amplification unit 1310 is connected to the power supply module 1400, the other end of the current amplification unit 1310 is grounded, and the power supply module 1400 is configured to supply power to the current amplification unit 1310.

[0136] Specifically, in the embodiments of this application, the current amplification unit 1310 in the filter module 1300 is an active device.

[0137] Furthermore, to reduce the design complexity of the filter module 1300, one end of the current amplification unit 1310 is connected to the power supply module 1400, while the other end of the current amplification unit 1310 is grounded. In other words, the current amplification unit 1310 is powered from one side. It is understandable that compared to the current amplification unit 1310 being powered from both sides, the design complexity of the filter module 1300 and the filter device 1000 is relatively lower.

[0138] In one example, to further reduce the design difficulty and cost of the filter module 1300 and the filter device 1000, the current amplification unit 1310 is powered by a single-sided positive voltage.

[0139] Thus, in this embodiment of the application, the filter module 1300 can be implemented based on the current amplification unit 1310 with single-sided power supply, thereby reducing the design difficulty of the filter module 1300 and the filter device 1000 to a certain extent.

[0140] Please refer to it again. Figure 5 In some embodiments of this application, the current amplification unit 1310 includes a first transistor 1311 and a second transistor 1312. The power supply module 1400 is connected to the collector of the first transistor 1311, the emitter of the first transistor 1311 is connected to the collector of the second transistor 1312, the emitter of the second transistor 1312 is grounded, the inverting amplification module 1200 is connected to the base of the first transistor 1311 and the base of the second transistor 1312, and the connection point of the first transistor 1311 and the second transistor 1312 is connected to the second isolation capacitor 1320.

[0141] Specifically, in this embodiment, the current amplification unit 1310 may be composed of a first transistor 1311 and a second transistor 1312. The collector of the first transistor 1311 receives the target voltage provided by the power supply module 1400, the emitter of the first transistor 1311 is connected to the collector of the second transistor 1312, and the connection point of the first transistor 1311 and the second transistor 1312 is connected to a second isolation capacitor 1320 to send a first current to the second isolation capacitor 1320.

[0142] Furthermore, in this embodiment, when the first voltage signal output by the inverting amplifier module 1200 is greater than the reference voltage Vref, the first transistor 1311 near the power supply module 1400 is turned on to provide injected compensation current. Conversely, when the first voltage signal output by the inverting amplifier module 1200 is less than the reference voltage Vref, the second transistor 1312 near the ground side is turned on to provide injected compensation current. It is understood that the current amplification module does not affect the conduction of the first voltage signal to the second isolation capacitor 1320, but it helps to provide a large compensation current.

[0143] As an example, assuming that both the first transistor 1311 and the second transistor 1312 are P-type transistors, then: when the first voltage signal output by the inverting amplifier module 1200 is greater than the reference voltage Vref, the first transistor 1311 is turned on, and the current output by the self-powered unit flows through the first switch, the second isolation capacitor 1320, and the access point B of the filter device 2000 into the filter device 2000, realizing the injection of compensation current; when the first voltage signal output by the inverting amplifier module 1200 is greater than the reference voltage Vref, the second transistor 1312 is turned on, and the current in the filter device 2000 flows from the access point B through the second isolation power supply and the second switch to ground, realizing the extraction of compensation current, or in other words, forming an inverted compensation current.

[0144] It is understandable that by switching the on and off of the first transistor 1311 and the second transistor 1312, the first voltage signal output by the inverting amplifier module 1200 can be converted into a large current output, thereby enhancing the compensation capability for common-mode noise. Moreover, the direction of the output current changes with the voltage signal, thus ensuring that it is in opposite phase to the common-mode noise current and effectively canceling the common-mode noise.

[0145] It is also understood that, in the embodiments of this application, the first transistor 1311 and the second transistor 1312 can be selected according to the actual situation. For example, in one example, the first transistor 1311 is an N-type transistor or a MOS transistor (a metal-oxide-semiconductor field-effect transistor), and the second transistor 1312 is a P-type transistor or a MOS transistor.

[0146] In one example, to further improve the stability of the circuit, a symmetrical resistor can be set between the first transistor 1311 and the second transistor 1312.

[0147] In one example, to further improve the stability of the circuit, a resistor or capacitor network can be set between the connection point of the first transistor 1311 and the second transistor 1312 and the second isolation capacitor 1320.

[0148] Thus, in this embodiment of the application, the current amplification unit 1310 can be implemented by the first transistor 1311 and the second transistor 1312.

[0149] Please refer to it again. Figure 6In some embodiments of this application, the current amplification unit 1310 includes a third transistor 1313, a fourth transistor 1314, a fourth impedance network 1315, a fifth impedance network 1316, and a sixth impedance network 1317. The inverting amplification module 1200 is connected to one end of the fourth impedance network 1315, one end of the fifth impedance network 1316, and one end of the sixth impedance network 1317. The other end of the fourth impedance network 1315 is connected to the base of the third transistor. The other end of the fifth impedance network 1316 is connected to the connection point of the third transistor 1313 and the fourth transistor 1314. The other end of the sixth impedance network 1317 is connected to the base of the fourth transistor. The connection point is connected to the second isolation capacitor 1320. The emitter of the fourth transistor 1314 is grounded.

[0150] Specifically, in the embodiments of this application, the current amplification unit 1310 may be composed of a third transistor 1313, a fourth transistor 1314, a fourth impedance network 1315, a fifth impedance network 1316, and a sixth impedance network 1317. In this circuit, the collector of the third transistor 1313 receives the target voltage provided by the power supply module 1400, the emitter of the fourth transistor 1314 is grounded, the first voltage signal output by the inverting amplifier module 1200 is connected to the connection point between the third transistor 1313 and the fourth transistor 1314 through the fifth impedance network 1316, the fourth impedance network 1315 is connected to the base of the third transistor 1313, the sixth impedance network 1317 is connected to the base of the fourth transistor 1314, and the connection point between the third transistor 1313 and the fourth transistor 1314 is also connected to the second isolation capacitor 1320, so that the second isolation capacitor 1320 can receive the first current based on the connection point between the third transistor 1313 and the fourth transistor 1314.

[0151] Furthermore, in this embodiment, when the first voltage signal output by the inverting amplifier module 1200 is greater than the reference voltage Vref, the third transistor 1313 near the power supply module 1400 is turned on to provide injected compensation current. Conversely, when the first voltage signal output by the inverting amplifier module 1200 is less than the reference voltage Vref, the fourth transistor 1314 near the ground side is turned on to provide injected compensation current. It is understood that the current amplification module does not affect the conduction of the first voltage signal to the second isolation capacitor 1320, but it helps to provide a large compensation current.

[0152] As an example, assuming that the third transistor 1313 and the fourth transistor 1314 are both P-type transistors, then: when the first voltage signal output by the inverting amplifier module 1200 is greater than the reference voltage Vref, the third transistor 1313 is turned on through the fourth impedance network 1315, and the current output by the self-powered unit flows into the filter device 2000 through the third transistor 1313, the second isolation capacitor 1320, and the access point B of the filter device 2000, realizing the injection of compensation current; when the first voltage signal output by the inverting amplifier module 1200 is less than the reference voltage Vref, the fourth transistor 1314 is turned on through the sixth impedance network 1317, and the current in the filter device 2000 flows from the access point B through the second isolation capacitor 1320 and the fourth transistor 1314 to ground, realizing the extraction of compensation current, or in other words, forming an inverted compensation current.

[0153] It is understandable that by switching the third and fourth switching diodes on and off, the first voltage signal output by the inverting amplifier module 1200 can be converted into a large current output, and the current direction is opposite to the common-mode noise current, thus effectively canceling the common-mode noise.

[0154] It is also understood that, in the embodiments of this application, the third transistor 1313 and the fourth transistor 1314 can be selected according to the actual situation. For example, in one example, the third transistor 1313 is an N-type transistor or a MOS transistor (metal-oxide-semiconductor field-effect transistor), and the fourth transistor 1314 is a P-type transistor or a MOS transistor.

[0155] In one example, to further improve the stability of the circuit, a symmetrical resistor can be set between the third transistor 1313 and the fourth transistor 1314.

[0156] In one example, to further improve the stability of the circuit, a resistor or capacitor network can be set between the connection point of the third transistor 1313 and the fourth transistor 1314 and the second isolation capacitor 1320.

[0157] Thus, in this embodiment of the application, the current amplification module can be implemented by the current amplification unit 1310 including a third transistor 1313, a fourth transistor 1314, a fourth impedance network 1315, a fifth impedance network 1316, and a sixth impedance network 1317.

[0158] Please refer to it again. Figure 6In some embodiments of this application, the inverting amplifier module 1200 includes a third operational amplifier 1225 and a seventh impedance network 1226. The third operational amplifier 1225 includes a fifth input terminal and a third output terminal. The third output terminal, the fifth impedance network 1316, the seventh impedance network 1226 and the fifth input terminal are connected in sequence.

[0159] Specifically, to achieve closed-loop negative feedback based on common-mode voltage and further ensure the filtering of common-mode voltage, in this embodiment, after the common-mode voltage acquired and output by the sampling module 1100 flows into the inverting amplifier module 1200 (the third operational amplifier 1225 used to invert and amplify the voltage signal) along the fifth input terminal of the third operational amplifier 1225, the third operational amplifier 1225 inverts and amplifies the common-mode voltage acquired and output by the sampling module 1100 to output... After the voltage signal is output, or in other words, after the first voltage signal is output, the first voltage signal flows to the fourth impedance network 1315, the fifth impedance network 1316 and the sixth impedance network 1317 respectively. After the fifth impedance network 1316 processes the received first voltage signal and outputs the corresponding processed voltage signal, the signal also flows into the seventh impedance network 1226. After being processed by the seventh impedance network 1226, it flows into the third operational amplifier 1225 again along the fifth input terminal of the third operational amplifier 1225, thus forming a closed-loop feedback.

[0160] Thus, in this embodiment of the application, a feedback loop for the third operational amplifier 1225 can be formed by sequentially connecting the third output terminal, the fifth impedance network 1316, the seventh impedance network 1226 and the fifth input terminal, thereby ensuring the robust processing of voltage signals by the third operational amplifier 1225 to a certain extent.

[0161] Please see Figure 7 In some embodiments of this application, the filter module 1300 includes a plurality of current amplification units 1310 arranged in parallel.

[0162] Specifically, considering that a higher compensation current injection is required to cancel common-mode voltage in some scenarios, or that a single-stage current amplification unit 1310 may not be able to meet the common-mode voltage cancellation requirements in some scenarios, in some embodiments of this application, multiple current amplification units 1310 can be arranged in parallel in the filter module 1300, thereby proportionally increasing the current of the filter module 1300.

[0163] Thus, in this embodiment, multiple current amplification units 1310 can be arranged in parallel in the filter module 1300, thereby ensuring that the compensation capability of the filter module 1300 meets the common-mode voltage cancellation requirements.

[0164] Please refer to it again. Figure 2 In some embodiments of this application, the filtering device 1000 includes a power supply module 1400, a sampling module 1100 configured to perform DC component boosting processing on the common-mode voltage signal according to a reference voltage to determine the processed voltage signal, and an inverting amplifier module 1200 configured to invert and amplify the processed voltage signal to determine a first voltage signal, wherein the reference voltage is half of the target voltage provided by the power supply module 1400.

[0165] Specifically, in order to further reduce the design difficulty and cost of the filter device 1000, in this embodiment of the application, the sampling module 1100 performs DC component boosting processing on the collected common-mode voltage signal based on the reference voltage Vref, thereby generating a processed voltage signal, and then outputs the processed voltage signal to the inverting amplifier module 1200, which inverts and amplifies the processed voltage signal to determine the first voltage signal.

[0166] It is understandable that after the sampling module 1100 performs DC component boosting processing on the common-mode voltage signal, other modules in the filter device 1000 located on the output side of the sampling module 1100, such as the inverting amplifier module 1200 and the filter module 1300, can be set to single-sided positive voltage power supply, thereby avoiding the need to consider negative voltage power supply, which reduces the design difficulty and design cost of the filter device 1000.

[0167] Thus, in this embodiment, the sampling module 1100 can perform DC component boosting processing on the common-mode voltage signal based on the reference voltage Vref to determine the processed voltage signal, and the inverting amplifier module 1200 can perform inversion and amplification processing on the processed voltage signal to determine the first voltage signal. This allows each module in the filter device 1000 to be configured to be powered by a single-sided positive voltage, thereby reducing the design difficulty and cost of the filter device 1000.

[0168] Please refer to it again. Figure 2 In some embodiments of this application, the filtering device 1000 includes a third isolation capacitor 1500, and the device to be filtered 2000, the third isolation capacitor 1500, and the sampling module 1100 are connected in sequence.

[0169] Specifically, in order to prevent the device to be filtered 2000 from supplying high voltage to the sampling module 1100, which could damage the sampling module 1100 and other modules connected to it, in this embodiment, the sampling module 1100 can be connected to the device to be filtered 2000 through a third isolation capacitor 1500, so that the high voltage in the circuit of the device to be filtered 2000 and the static low voltage of the sampling module 1100 can be isolated from each other based on the third isolation capacitor 1500.

[0170] Furthermore, it is understood that the isolation capacitor has high-pass characteristics, and thus, the third isolation capacitor 1500 also helps to suppress low-frequency signals below 150kHz from entering the sampling module 1100, thereby ensuring the effectiveness of the common-mode voltage sampled and output by the sampling module 1100.

[0171] Additionally, it is understandable that the number of the third isolation capacitor (1500) can be set according to the actual situation; if it is one, then... Figure 2 As shown, if there are multiple capacitors, they can be connected in parallel at one end of the sampling module 1100, and the other end can be connected to the same or different positions in the device to be filtered 2000. It is understandable that when connected to different positions, the sampling voltage can be the median value of these connected positions.

[0172] Thus, in this embodiment of the application, the filter device 2000, the third isolation capacitor 1500 and the sampling module 1100 can be connected in sequence to ensure the stable operation of the sampling module 1100.

[0173] For a clearer illustration of the filter device 1000 in the embodiments of this application, please also refer to... Figure 2 , Figure 8 , Figure 9 , Figure 10 and Figure 11 , Figure 8 , Figure 9 , Figure 10 and Figure 11 These are all schematic diagrams illustrating application scenarios in certain embodiments of this application. Specifically, such as... Figure 2 As shown in the embodiments of this application, the filtering device 1000 may be composed of a third isolation capacitor 1500, a sampling module 1100, a current isolation unit 1210, an inverting amplifier unit 1220, a current amplifier unit 1310, and a second isolation capacitor 1320.

[0174] Furthermore, one end of the third isolation capacitor 1500 can be connected to access point A on the circuit of the device to be filtered 2000 (such as an electrically controlled high-voltage bus), and the other end is connected to the sampling module 1100. Correspondingly, one end of the second isolation capacitor 1320 is connected to the current amplification unit 1310, and the other end can be connected to access point B on the circuit of the device to be filtered 2000 (such as an electrically controlled high-voltage bus).

[0175] The third isolation capacitor 1500 isolates the high voltage of the circuit of the device to be filtered 2000 from the static low voltage of the sampling module 1100, and suppresses low-frequency signals below 150kHz from entering the sampling module 1100. It is understood that there can be one or more third isolation capacitors 1500. When the number of third isolation capacitors 1500 is greater than one, multiple third isolation capacitors 1500 can be connected in parallel near one end of the sampling module 1100, and the other end can be connected to the same or different locations in the circuit of the device to be filtered 2000. It is also understood that when connected to different locations, the sampling voltage will be the median value of these connected locations.

[0176] The sampling module 1100 can acquire and output a common-mode voltage signal, and boost the DC component of the output voltage signal through the connected reference voltage Vref, so that all subsequent units can be powered by a single positive voltage, avoiding negative voltage power supply.

[0177] The current isolation unit 1210 blocks the current flow between the two circuits and performs equivalent transmission of voltage signals, avoiding the impact of the impedance of subsequent circuits on the sampling accuracy.

[0178] The inverting amplifier unit 1220 can amplify the voltage signal input from the current isolation module in reverse phase. During the inverting amplification process, the DC component of the "input voltage signal" can be canceled by the connected reference voltage Vref, avoiding a large change in the amplitude of the DC component of the amplified output signal, so that the DC component of the amplified output signal is the same as or similar to the DC component of the "input voltage signal".

[0179] The current amplification unit 1310 can follow the injected compensation current generated on the second isolation capacitor 1320 in real time and supports multi-stage parallel connection.

[0180] The second isolation capacitor 1320 isolates the high voltage of the filter device 2000 circuit from the low voltage of the current amplification unit 1310. Simultaneously, the voltage difference generated on both sides induces current flow, forming an inverse common-mode compensation current that is injected into the filter device 2000 circuit through connection point B. This partially offsets the original common-mode current in the main circuit, thereby reducing the common-mode voltage. It is understood that the number of second isolation capacitors 1320 can be set according to actual conditions. When the number of second isolation capacitors 1320 is greater than one, one end of each second isolation capacitor 1320 can be connected in parallel, and the other ends of each second isolation capacitor 1320 can be connected to the same or different locations. If all are connected to connection point A or B, a closed-loop negative feedback is formed. If the other ends of each second isolation capacitor 1320 are connected to different locations, it is necessary to confirm whether the formed negative feedback is reasonable.

[0181] It is understandable that the filtering circuits in the related technologies are generally suitable for low-power common-mode rejection applications, while the filtering device 1000 in the embodiments of this application has a wider range of applicable power because it includes a current amplification unit 1310.

[0182] It is also understandable that some related technologies do not offer low-power performance. For example, the power consumption of the source filter circuit mentioned above always needs to be maintained at a high level and will not change with the compensation requirements. In contrast, the current amplification stage in the embodiment of this application can maintain low power consumption while ensuring the compensation current.

[0183] Furthermore, it is understood that some related technologies require both positive and negative voltage power supply, while negative voltage power supply leads to higher costs and more complex power supply circuits. In contrast, the filter device 1000 provided in this application does not require negative voltage power supply.

[0184] It is also understandable that some solutions proposed in related technologies lack versatility and require specific matching, or the solutions themselves are designed for specific application scenarios, making them inconvenient to migrate. In contrast, the filter device 1000 provided in this application, based on closed-loop negative feedback of common-mode voltage, can be migrated and applied as long as the noise level is similar.

[0185] Furthermore, some related technologies employ transformer voltage / current sampling or compensation, but transformers are relatively large, thus affecting their usability to some extent. In contrast, the filter device 1000 provided in this application does not require a transformer, and through capacitor sampling / compensation, it ensures that the filter device 1000 itself is relatively small in size.

[0186] Furthermore, some solutions proposed in related technologies are designed for low-voltage applications and do not consider high-voltage isolation, thus lacking sufficient safety for high-voltage applications. In contrast, the filtering device 1000 provided in this application can achieve high-voltage isolation based on the third isolation capacitor 1500 and the second isolation capacitor 1320, thereby ensuring robust filtering of common-mode voltage.

[0187] Exemplary, with Figure 8 For example, for a motor controller with a bus voltage of 600V and a switching frequency of 10kHz, the original filter is a passive filter composed of a common-mode magnetic ring and a Y capacitor. Without changing the original filter circuit, a filter device 1000 is connected in parallel to the original filter. The connected filter device 1000 uses resistor voltage divider sampling and operational amplifier current isolation, with a current compensation limit designed to be 1A. Simulation and experimental tests were performed before and after connecting the filter device 1000. The results before and after the addition are shown below. Figure 9 , Figure 10 and Figure 11 As shown.

[0188] in, Figure 9 In the spectrum diagram shown, the horizontal axis represents frequency, ranging from 150 kHz to 10 MHz, and the vertical axis represents receiver-detected noise, using a logarithmic scale, ranging from 1.0 μV to 1.0 V. Figure 9 The two curves represent the situation before and after the addition of filter device 1000. From... Figure 9 As can be seen, before the addition of filter 1000, the noise fluctuated significantly across the entire frequency range, especially in the 150kHz-1.0MHz band. After the addition of filter 1000, the noise in most frequency bands was significantly reduced, and the common-mode voltage in the 150kHz-5MHz band decreased by up to 18 times, or up to 25dB.

[0189] as well as, Figure 10 and Figure 11 In the spectrum diagrams shown, the horizontal axis represents frequency (Hz), ranging from 150k to 108m; the vertical axis represents the noise level detected at the receiver (dBμV), ranging from 32.5 to 130. Figure 10 This can characterize the frequency domain experimental results of the common-mode voltage at the receiver before the 1000-meter-high filter. Figure 11 This can characterize the frequency domain experimental results of the common-mode voltage at the receiver after connecting the filter device 1000. From Figure 10 and Figure 11 As can be seen, after adding the filter device 1000, the common-mode voltage in the 150kHz-5MHz frequency band drops by up to 20dB, which proves that the filter device 1000 has good filtering performance.

[0190] This application provides an electronic device, which includes the filtering device 1000 described above.

[0191] This application also provides a vehicle that includes the above-described filter device 1000.

[0192] In this specification, the terms "specifically," "furthermore," "particularly," "understandably," etc., refer to specific features, structures, materials, or characteristics described in connection with embodiments or examples that are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0193] Any process or method described in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing a particular logical function or process, and the scope of the preferred embodiments of this application includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the function involved, as will be understood by those skilled in the art to which embodiments of this application pertain.

[0194] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A filtering device (1000), characterized in that, The filtering device (1000) is connected to the device to be filtered (2000), and the filtering device (1000) includes a sampling module (1100), an inverting amplification module (1200) and a filtering module (1300) connected in sequence. The sampling module (1100) is configured to acquire the common-mode voltage signal of the device to be filtered (2000); The inverting amplifier module (1200) is configured to invert and amplify the common-mode voltage signal to determine the first voltage signal; The filtering module (1300) is configured to supply a compensation current that is inverse of the common-mode voltage signal to the device to be filtered (2000) according to the first voltage signal.

2. The filtering device (1000) according to claim 1, characterized in that, The inverting amplifier module (1200) includes a current isolation unit (1210) and an inverting amplifier unit (1220), and the sampling module (1100), the current isolation unit (1210), the inverting amplifier unit (1220) and the filtering module (1300) are connected in sequence; The current isolation unit (1210) is configured to send a second voltage signal corresponding to the common-mode voltage signal to the inverting amplifier unit (1220); The inverting amplifier unit (1220) is configured to invert and amplify the second voltage signal to determine the first voltage signal.

3. The filtering device (1000) according to claim 2, characterized in that, The filtering device (1000) includes a power supply module (1400), one end of the current isolation unit (1210) and one end of the inverting amplifier unit (1220) are both connected to the power supply module (1400), and the other end of the current isolation unit (1210) and the other end of the inverting amplifier unit (1220) are both grounded; The power supply module (1400) is configured to supply power to the current isolation unit (1210) and the inverting amplifier unit (1220).

4. The filtering device (1000) according to claim 3, characterized in that, The current isolation unit (1210) includes a first resistor (1211), a second resistor (1212), a third resistor (1213), and a transistor (1214). The power supply module (1400) is connected to the base of the transistor (1214) through the first resistor (1211). One end of the second resistor (1212) is connected to the base, and the other end of the second resistor (1212) is grounded. The emitter of the transistor (1214) is grounded through the third resistor (1213). The sampling module (1100) is connected to the base, and the emitter is connected to the inverting amplifier unit (1220).

5. The filtering device (1000) according to claim 3, characterized in that, The current isolation unit (1210) includes a first operational amplifier (1215), which includes a first input terminal, a second input terminal and a first output terminal. The sampling module (1100) is connected to the first input terminal, the second input terminal is connected to the first output terminal, and the first output terminal is connected to the inverting amplifier unit (1220).

6. The filtering device (1000) according to claim 3, characterized in that, The inverting amplifier unit (1220) includes a first impedance network (1221), a second operational amplifier (1222), and a second impedance network (1223). The second operational amplifier (1222) includes a third input terminal, a fourth input terminal, and a second output terminal. The current isolation unit (1210) is connected to one end of the first impedance network (1221), and the other end of the first impedance network (1221) is connected to the third input terminal. The fourth input terminal is connected to a reference voltage. The second output terminal is connected to the filter module (1300) and one end of the second impedance network (1223). The other end of the second impedance network (1223) is connected to the third input terminal. The reference voltage is half of the target voltage provided by the power supply module (1400).

7. The filtering device (1000) according to claim 3, characterized in that, The inverting amplifier unit (1220) includes a third impedance network (1224) and a third operational amplifier (1225). The third operational amplifier (1225) includes a fifth input terminal, a sixth input terminal, and a third output terminal. The current isolation unit (1210) is connected to one end of the third impedance network (1224), and the other end of the third impedance network (1224) is connected to the fifth input terminal. The sixth input terminal is connected to a reference voltage, and the third output terminal is connected to the filter module (1300). The reference voltage is half of the target voltage provided by the power supply module (1400).

8. The filtering device (1000) according to claim 1, characterized in that, The filtering module (1300) includes a first isolation capacitor, and the inverting amplifier module (1200), the first isolation capacitor and the device to be filtered (2000) are connected in sequence. The first isolation capacitor is configured to supply the compensation current to the device to be filtered (2000) according to the first voltage signal.

9. The filtering device (1000) according to claim 1, characterized in that, The filtering module (1300) includes a current amplification unit (1310) and a second isolation capacitor (1320), and the inverting amplification module (1200), the current amplification unit (1310), the second isolation capacitor (1320) and the device to be filtered (2000) are connected in sequence. The current amplification unit (1310) is configured to amplify the first current corresponding to the first voltage signal to determine the second current; The second isolation capacitor (1320) is configured to supply a compensation current that is inverse to the common-mode voltage signal to the filter device (2000) according to the second current.

10. The filtering device (1000) according to claim 9, characterized in that, The filtering device (1000) includes a power supply module (1400), one end of the current amplification unit (1310) is connected to the power supply module (1400), and the other end of the current amplification unit (1310) is grounded; The power supply module (1400) is configured to supply power to the current amplification unit (1310).

11. The filtering device (1000) according to claim 10, characterized in that, The current amplification unit (1310) includes a first transistor (1311) and a second transistor (1312). The power supply module (1400) is connected to the collector of the first transistor (1311). The emitter of the first transistor (1311) is connected to the collector of the second transistor (1312). The emitter of the second transistor (1312) is grounded. The inverting amplification module (1200) is connected to the base of the first transistor (1311) and the base of the second transistor (1312). The connection point between the first transistor (1311) and the second transistor (1312) is connected to the second isolation capacitor (1320).

12. The filtering device (1000) according to claim 10, characterized in that, The current amplification unit (1310) includes a third transistor (1313), a fourth transistor (1314), a fourth impedance network (1315), a fifth impedance network (1316), and a sixth impedance network (1317). The inverting amplification module (1200) is connected to one end of the fourth impedance network (1315), one end of the fifth impedance network (1316), and one end of the sixth impedance network (1317). The other end of the fourth impedance network (1315) is connected to the base of the third transistor. The other end of the fifth impedance network (1316) is connected to the connection point of the third transistor (1313) and the fourth transistor (1314). The other end of the sixth impedance network (1317) is connected to the base of the fourth transistor. The connection point is connected to the second isolation capacitor (1320). The emitter of the fourth transistor (1314) is grounded.

13. The filtering device (1000) according to claim 12, characterized in that, The inverting amplifier module (1200) includes a third operational amplifier (1225) and a seventh impedance network (1226). The third operational amplifier (1225) includes a fifth input terminal and a third output terminal. The third output terminal, the fifth impedance network (1316), the seventh impedance network (1226) and the fifth input terminal are connected in sequence.

14. The filtering device (1000) according to claim 9, characterized in that, The filtering module (1300) includes a plurality of current amplification units (1310) arranged in parallel.

15. The filtering device (1000) according to claim 1, characterized in that, The filtering device (1000) includes a power supply module (1400), which is configured to provide a target voltage to the inverting amplifier module (1200) and the filtering module (1300); The sampling module (1100) is configured to perform DC component boosting processing on the common-mode voltage signal based on a reference voltage to determine the processed voltage signal, wherein the reference voltage is half of the target voltage provided by the power supply module (1400). The inverting amplifier module (1200) is configured to invert and amplify the processed voltage signal to determine the first voltage signal.

16. The filtering device (1000) according to claim 1, characterized in that, The filtering device (1000) includes a third isolation capacitor (1500), and the device to be filtered (2000), the third isolation capacitor (1500) and the sampling module (1100) are connected in sequence.

17. An electronic device, characterized in that, The electronic device includes the filtering device (1000) according to any one of claims 1-16.

18. A vehicle, characterized in that, The vehicle includes a filter device (1000) as described in any one of claims 1-16, or includes an electronic device as described in claim 17.

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