Active noise matching transformer

Abstract

The present invention provides an active noise matching transformer, which can be applied to the field of transformer technology. The active noise matching transformer includes: a primary coil, a feedback module, a secondary coil, and a first active amplifier. The first end of the primary coil is electrically connected to the output end of a magnetic fluid angular vibration sensor, and the second end of the primary coil is electrically connected to the first end of the feedback module, so that the primary coil and the secondary coil are electromagnetically coupled. The two ends of the secondary coil are respectively electrically connected to the two input ends of the first active amplifier. The second end of the feedback module receives the output signal of the secondary-side loop in which the secondary coil is located, and the third end of the feedback module is grounded. The number of turns of the secondary coil and the equivalent resistance of the feedback module are configured so that, when the system voltage gain of the active noise matching transformer is equal to the target voltage gain, the equivalent input impedance of the primary-side loop in which the primary coil is located is equal to the target impedance.

Description

Technical Field

[0001] The present invention relates to the technical field of transformers, and more particularly to an active noise matching transformer. Background Art

[0002] Magnetic fluid angular vibration sensors are high-frequency angular vibration sensors characterized by high sensitivity, a wide operating range, low noise, and a compact size. These sensors are based on the principles of conductive fluid dynamics. When a vibration signal is input, the conductive fluid moves relative to the magnetic field, generating an induced potential that detects the angular vibration signal.

[0003] The angular vibration signal detected by the magnetic fluid angular vibration sensor is weak. By adding a noise matching transformer between the sensor's sensitive element and the active amplifier to form a noise matching network, the high-frequency angular vibration signal can be extracted.

[0004] However, in practical applications, the noise matching transformer has harmonic distortion in the low frequency band, for example, the frequency band below 5Hz, which is manifested as output asymmetry and waveform distortion, resulting in low working efficiency and performance degradation of the magnetic fluid angular vibration sensor in the low frequency band. Summary of the Invention

[0005] In view of the above problems, the present invention provides an active noise matching transformer.

[0006] The active noise matching transformer provided by the present invention includes: a primary coil, a feedback module, a secondary coil and a first active amplifier; wherein the first end of the primary coil is electrically connected to the output end of the magnetic fluid angular vibration sensor, the second end of the primary coil is electrically connected to the first end of the feedback module, and the primary coil and the secondary coil are electromagnetically coupled; the two ends of the secondary coil are respectively electrically connected to the two input ends of the first active amplifier; the second end of the feedback module receives the output signal of the secondary side loop where the secondary coil is located, and the third end of the feedback module is grounded; wherein the number of turns of the secondary coil and the equivalent resistance of the feedback module are configured to be in the active noise matching transformer When the system voltage gain is equal to the target voltage gain, the equivalent input impedance of the primary-side loop where the primary coil is located is set to the target impedance, wherein the target voltage gain is the system voltage gain when the active noise matching transformer does not include a feedback module. The target voltage gain is calculated when the equivalent output resistance of the loop where the primary coil, the secondary coil, and the magnetic fluid angular vibration sensor are located is equal to the optimal source resistance of the first active amplifier. The optimal source resistance of the first active amplifier is calculated based on the power spectral density of the equivalent input voltage and the power spectral density of the equivalent input current of the first active amplifier.

[0007] For example, the feedback module includes a first feedback resistor and a second feedback resistor; wherein, the first end of the first feedback resistor is electrically connected to the second end of the primary coil and the first end of the second feedback resistor, and the second end of the first feedback resistor is grounded; the second end of the second feedback resistor is electrically connected to the output end of the first active amplifier.

[0008] For example, the resistance of the second feedback resistor is configured based on the turns ratio of the secondary coil to the primary coil, the resistance of the source resistor, and the voltage gain coefficient of the first active amplifier, wherein the source resistor is the equivalent resistance of the sensor sensitive element included in the magnetic fluid angular vibration sensor.

[0009] For example, the resistance of the first feedback resistor is configured according to the turns ratio of the secondary coil to the primary coil and the resistance of the source resistor.

[0010] For example, a first target transfer function of the system voltage gain of the active noise matching transformer is obtained by the following operations: adding the resistance of the first feedback resistor and the resistance of the second feedback resistor, and multiplying the sum by the inductance of the primary coil, the turns ratio of the secondary coil to the primary coil, and the voltage gain coefficient of the first active amplifier, to obtain a first term; multiplying the resistance of the first feedback resistor and the resistance of the second feedback resistor, to obtain a second term; multiplying the resistance of the first feedback resistor and the resistance of the source resistor, to obtain a third term; multiplying the resistance of the second feedback resistor and the resistance of the source resistor, to obtain a fourth term; adding the product of the turns ratio of the secondary coil to the primary coil, the voltage gain coefficient of the first active amplifier, and the resistance of the first feedback resistor, the resistance of the first feedback resistor, and the resistance of the second feedback resistor, and multiplying the sum by the inductance of the primary coil, to obtain a fifth term; and obtaining the first target transfer function based on the first, second, third, fourth, and fifth terms.

[0011] For example, the feedback module includes a first feedback resistor, a second feedback resistor, and a second active amplifier; wherein, the first end of the first feedback resistor is electrically connected to the second end of the primary coil and the first end of the second feedback resistor, and the second end of the first feedback resistor is grounded; the second end of the second feedback resistor is electrically connected to the output end of the second active amplifier; and the two input ends of the second active amplifier are respectively electrically connected to the two ends of the secondary coil.

[0012] For example, the resistance of the second feedback resistor is determined based on the turns ratio of the secondary coil to the primary coil, the resistance of the source resistor, and the voltage gain coefficient of the second active amplifier, wherein the source resistor is the equivalent resistance of the sensor sensitive element included in the magnetic fluid angular vibration sensor.

[0013] For example, the resistance of the first feedback resistor is configured according to the turns ratio of the secondary coil to the primary coil and the resistance of the source resistor.

[0014] For example, the second target transfer function of the system voltage gain of the active noise matching transformer is obtained by the following operations: adding the resistance of the first feedback resistor and the resistance of the second feedback resistor, and multiplying the sum by the inductance of the primary coil, the turns ratio of the secondary coil to the primary coil, and the voltage gain coefficient of the first active amplifier, to obtain a first term; multiplying the resistance of the first feedback resistor and the resistance of the second feedback resistor, to obtain a second term; multiplying the resistance of the first feedback resistor and the resistance of the source resistor, to obtain a third term; multiplying the resistance of the second feedback resistor and the resistance of the source resistor, to obtain a fourth term; adding the product of the turns ratio of the secondary coil to the primary coil, the voltage gain coefficient of the second active amplifier, and the resistance of the first feedback resistor, the resistance of the first feedback resistor, and the resistance of the second feedback resistor, and multiplying the sum by the inductance of the primary coil, to obtain a fifth term; and obtaining the second target transfer function based on the first, second, third, fourth, and fifth terms.

[0015] For example, the number of turns of the secondary coil is an integer multiple of the target number of turns.

[0016] According to an embodiment of the present invention, an active noise matching transformer is provided. By electrically connecting the first end of a primary coil to the output end of a magnetic fluid angular vibration sensor, the second end of the primary coil to the first end of a feedback module, electromagnetically coupling the primary coil to a secondary coil, and electrically connecting the two ends of the secondary coil to the two input ends of a first active amplifier, respectively, and the second end of the feedback module to receive the output signal of the secondary-side loop in which the secondary coil resides, and grounding the third end of the feedback module, the number of turns of the secondary coil and the equivalent resistance of the feedback module are adjusted to ensure that the equivalent input impedance of the primary-side loop in which the primary coil resides is equal to the target impedance, provided that the system voltage gain of the active noise matching transformer is equal to the target voltage gain. Furthermore, by adjusting the number of turns of the secondary coil and the equivalent resistance of the feedback module, the equivalent input impedance of the primary-side loop can be increased while maintaining the system voltage gain unchanged, thereby reducing the current in the corresponding primary-side loop and preventing magnetic core saturation. This solves the problem of harmonic distortion in the low-frequency band and improves the operating efficiency and performance of the magnetic fluid angular vibration sensor in the low-frequency band.

[0017] At the same time, since the target voltage gain is the system voltage gain when the active noise matching transformer does not include the feedback module, the target voltage gain is calculated when the equivalent output resistance of the loop containing the primary coil, the secondary coil, and the magnetic fluid angular vibration sensor is equal to the optimal source resistance of the first active amplifier. The optimal source resistance of the first active amplifier is calculated based on the power spectral density of the equivalent input voltage and the power spectral density of the equivalent input current of the first active amplifier. At the target voltage gain, the first active amplifier operates in an optimal noise figure state, i.e., a noise matching state. The output signal of the first active amplifier is less affected by the noise voltage and more accurate. By adjusting the number of turns of the secondary coil and the equivalent resistance of the feedback module while maintaining the system voltage gain of the active noise matching transformer equal to the target voltage gain, the output signal of the first active amplifier can be less affected by the noise voltage, the output signal of the first active amplifier is more accurate, and the signal range of the output signal remains unchanged. At the same time, the current in the corresponding primary-side loop is reduced to prevent magnetic core saturation. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above contents and other objects, features and advantages of the present invention will become more apparent through the following description of the embodiments of the present invention with reference to the accompanying drawings.

[0019] Figure 1 A schematic structural diagram of an active noise matching transformer according to an embodiment of the present invention is shown.

[0020] Figure 2 FIG. 4 shows a structural diagram of an active noise matching transformer according to another embodiment of the present invention.

[0021] Figure 3 FIG. 4 shows a structural diagram of an active noise matching transformer according to another embodiment of the present invention. DETAILED DESCRIPTION

[0022] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present invention. In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of embodiments of the present invention. However, it is apparent that one or more embodiments may also be implemented without these specific details. In addition, in the following description, descriptions of known structures and technologies are omitted to avoid unnecessary confusion of the concept of the present invention.

[0023] The terms used herein are only for describing specific embodiments and are not intended to limit the present invention. The terms "comprise", "include", etc. used herein indicate the presence of the features, steps, operations and / or components, but do not exclude the presence or addition of one or more other features, steps, operations or components.

[0024] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0025] When expressions such as "at least one of A, B, and C, etc." are used, they should generally be interpreted in accordance with the meaning commonly understood by those skilled in the art (for example, "a system having at least one of A, B, and C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.).

[0026] Related technologies employ a noise matching transformer (NMT) between the sensor's sensitive element and active amplifier to form a noise matching network, enabling the extraction of high-frequency angular vibration signals. However, in practical applications, NMTs exhibit harmonic distortion at low frequencies, such as those below 5 Hz. This can manifest as output asymmetry and waveform distortion. Analysis reveals that the harmonic distortion is caused by the low input impedance of the NMT's primary circuit at low frequencies, resulting in high primary circuit currents. This in turn causes the NMT's core to saturate, leading to nonlinear characteristics. In the saturated state, the output signal waveform becomes distorted, becoming sharp or irregular. These irregularities manifest as harmonics. Spectral analysis reveals that, in addition to the fundamental frequency signal, harmonic components at integer multiples, such as 2nd and 3rd multiples, can also be observed. These harmonics impose additional burdens on other components in the circuit and affect sensor operation. Prolonged operation in a saturated state can also damage the sensor and reduce system testing efficiency. Therefore, it is particularly important to solve the harmonic distortion problem of this active noise matching transformer in the low-frequency domain and improve the working efficiency of the sensor in the low-frequency domain in order to improve the performance of the sensor.

[0027] Existing solutions to core saturation include increasing the air gap and selecting appropriate core materials. Introducing an air gap in the core increases the total length of the magnetic flux path and delays saturation, but this significantly reduces the core's permeability, resulting in a decrease in the inductance of the noise matching transformer windings and potentially causing nonlinear distortion in the output signal. Another solution is to select a core material with a higher saturation flux density, which can extend the operating range of the noise matching transformer. However, the sensor cores described in this invention are made of high-permeability soft magnetic materials, and alternative core materials have yet to be found.

[0028] In light of this, embodiments of the present invention provide an active noise matching transformer for use in the transformer field. By modifying the circuit structure, the present invention reduces the primary-side current of the noise matching transformer, preventing saturation of the transformer core in the low-frequency domain and thus harmonic distortion.

[0029] The present invention provides an active noise matching transformer suitable for a magnetic fluid angular vibration sensor, and proposes an improvement scheme based on circuit topology optimization to address the technical defect of the magnetic fluid angular vibration sensor having harmonic distortion in the low frequency band. The active noise matching transformer is composed of a noise matching transformer and an active amplifier. Its core innovation lies in: constructing a current attenuation channel by optimizing the ratio of the number of turns of the windings on both sides of the noise matching transformer, and introducing a feedback resistor network to form a dynamic compensation loop. Under the premise of maintaining a constant system voltage gain, the present invention adjusts the equivalent input impedance of the primary side by adjusting the number of turns of the secondary coil and the equivalent resistance of the feedback module, effectively reducing the input current of the primary side, and fundamentally solving the problem of output waveform distortion caused by the saturation of the magnetic core of the noise matching transformer. Among them, the noise matching transformer includes a primary coil and a secondary coil.

[0030] Figure 1 A schematic structural diagram of an active noise matching transformer according to an embodiment of the present invention is shown.

[0031] like Figure 1 As shown, the active noise matching transformer 100 may include a primary coil 110 , a feedback module 120 , a secondary coil 130 and a first active amplifier 140 .

[0032] A first end of the primary coil 110 may be electrically connected to an output end of the magnetic fluid angular vibration sensor 101 , a second end of the primary coil 110 may be electrically connected to a first end of the feedback module 120 , and the primary coil 110 may be electromagnetically coupled to the secondary coil 130 .

[0033] The two ends of the secondary coil 130 can be electrically connected to the two input ends of the first active amplifier 140. The second end of the feedback module 120 can receive the output signal of the secondary side loop where the secondary coil 130 is located. The third end of the feedback module 120 can be grounded.

[0034] For example, the second end of the feedback module 120 can receive the output signal output by the first active amplifier 140 in the secondary side loop where the secondary coil 130 is located. Alternatively, the second end of the feedback module 120 can receive the output signal output by the secondary coil 130 .

[0035] The number of turns of the secondary coil 130 and the equivalent resistance of the feedback module 120 are configured so that, when the system voltage gain of the active noise matching transformer 100 is equal to the target voltage gain, the equivalent input impedance of the primary-side loop containing the primary coil 110 is equal to the target impedance. The target voltage gain is the system voltage gain of the active noise matching transformer 100 without the feedback module. The target voltage gain is calculated when the equivalent output resistance of the loop containing the primary coil, secondary coil, and magnetic fluid angular vibration sensor is equal to the optimal source resistance of the first active amplifier. The optimal source resistance of the first active amplifier is calculated based on the power spectral density of the equivalent input voltage and the power spectral density of the equivalent input current of the first active amplifier. At this point, the equivalent output resistance of the secondary side of the active noise matching transformer is equal to the optimal source resistance of the first active amplifier 140.

[0036] exist Figure 1 In FIG, the sensitive element 1011 of the magnetic fluid angular vibration sensor 101 outputs a signal after being amplified in two stages by the active noise matching transformer 100. The equivalent resistance of the sensitive element 1011 of the magnetic fluid angular vibration sensor 101 is the source resistance R S .

[0037] According to an embodiment of the present invention, an active noise matching transformer is provided. By electrically connecting the first end of a primary coil to the output end of a magnetic fluid angular vibration sensor, the second end of the primary coil to the first end of a feedback module, electromagnetically coupling the primary coil to a secondary coil, and electrically connecting the two ends of the secondary coil to the two input ends of a first active amplifier, respectively, and the second end of the feedback module to receive the output signal of the secondary-side loop in which the secondary coil resides, and grounding the third end of the feedback module, the number of turns of the secondary coil and the equivalent resistance of the feedback module are adjusted to ensure that the equivalent input impedance of the primary-side loop in which the primary coil resides is equal to the target impedance, provided that the system voltage gain of the active noise matching transformer is equal to the target voltage gain. Furthermore, by adjusting the number of turns of the secondary coil and the equivalent resistance of the feedback module, the equivalent input impedance of the primary-side loop can be increased while maintaining the system voltage gain unchanged, thereby reducing the current in the corresponding primary-side loop and preventing magnetic core saturation. This solves the problem of harmonic distortion in the low-frequency band and improves the operating efficiency and performance of the magnetic fluid angular vibration sensor in the low-frequency band.

[0038] At the same time, since the target voltage gain is the system voltage gain when the active noise matching transformer does not include the feedback module, the target voltage gain is calculated when the equivalent output resistance of the loop containing the primary coil, the secondary coil, and the magnetic fluid angular vibration sensor is equal to the optimal source resistance of the first active amplifier. The optimal source resistance of the first active amplifier is calculated based on the power spectral density of the equivalent input voltage and the power spectral density of the equivalent input current of the first active amplifier. At the target voltage gain, the first active amplifier operates in an optimal noise figure state, i.e., a noise matching state. The output signal of the first active amplifier is less affected by the noise voltage and more accurate. By adjusting the number of turns of the secondary coil and the equivalent resistance of the feedback module while maintaining the system voltage gain of the active noise matching transformer equal to the target voltage gain, the output signal of the first active amplifier can be less affected by the noise voltage, the output signal of the first active amplifier is more accurate, and the signal range of the output signal remains unchanged. At the same time, the current in the corresponding primary-side loop is reduced to prevent magnetic core saturation.

[0039] The active noise matching transformer provided in an embodiment of the present invention can change the number of winding turns in the secondary coil when the same angular vibration signal is input to the active noise matching transformer and the number of winding turns in the primary coil is not changed. At the same time, a feedback module is added to increase the equivalent input impedance on the primary side and reduce the corresponding primary side current while maintaining the system voltage gain unchanged. Based on the circuit characteristics of the active noise matching transformer, the circuit structure is adjusted to reduce the primary side current of the noise matching transformer to prevent core saturation, thereby solving the problem of harmonic distortion in the low frequency band.

[0040] According to an embodiment of the present invention, a noise matching network is formed by adding a noise matching transformer between the sensitive element and the first active amplifier of the magnetic fluid angular vibration sensor, so that the optimal source resistance of the first active amplifier is as close as possible to the source resistance of the sensitive element, thereby achieving a minimum noise coefficient and a two-stage signal amplification operation, thereby realizing the extraction of high-frequency angular vibration signals.

[0041] The active noise matching transformer provided according to the embodiment of the present invention has a simple circuit design and low required cost, and has obvious advantages compared to other magnetic core materials and structures.

[0042] According to an embodiment of the present invention, the equivalent voltage noise of the sensitive element 1011 of the magnetic fluid angular vibration sensor 101 can be e s The equivalent input voltage noise and current noise of the first active amplifier 140 can be expressed as e n and i n The power spectral density (PSD) of the equivalent input voltage of the first active amplifier 140 can be expressed as , the PSD of the equivalent input current of the first active amplifier 140 can be expressed as The optimal source resistance corresponding to the minimum noise coefficient of the first active amplifier 140 is .

[0043] When the first active amplifier 140 is directly electrically connected to the output end of the magnetic fluid angular vibration sensor 101 , the optimal source resistance of the first active amplifier 140 is With the source resistance R S When the first active amplifier 140 is equal to the first active amplifier 140, the first active amplifier 140 operates in the optimal noise coefficient state, which is called the noise matching state. With the source resistance R S When the voltages are not equal, a transformer can be added between the sensitive element 1011 of the magnetic fluid angular vibration sensor 101 and the first active amplifier 140 to enable the first active amplifier 140 to operate in an optimal noise coefficient state. That is, by removing the feedback module 120 from the active noise matching transformer 100, or by excluding the feedback module 120 from the active noise matching transformer 100, and grounding the second end of the primary coil 110, the equivalent output resistance of the loop including the primary coil 110, the secondary coil 130, and the magnetic fluid angular vibration sensor 101 is increased by the square of the turns ratio, so that the equivalent output resistance of the loop including the primary coil 110, the secondary coil 130, and the magnetic fluid angular vibration sensor 101 is equal to the optimal source resistance of the first active amplifier 140, thereby achieving noise matching and achieving the minimum noise coefficient. The transformer includes a primary coil 110 and a secondary coil 130, k is the Boltzmann constant, T is the absolute temperature, is the source resistance R S resistance value.

[0044] When the active noise matching transformer 100 does not include the feedback module 120 , the turns ratio of the secondary winding 130 to the primary winding 110 is n1, which is equal to the optimal turns ratio of the transformer corresponding to the minimum noise figure. The primary winding of the noise matching transformer is one turn, and the turns ratio is equal to the number of turns on the secondary winding. An active noise matching transformer without a feedback module has a low equivalent input impedance in the low-frequency domain. Under the same angular vibration signal input, the equivalent input voltage remains constant, resulting in high primary-side loop current, which can easily cause the noise matching transformer's core to saturate, leading to distortion and distortion of the output waveform.

[0045] Therefore, the present invention proposes a scheme of adding a feedback loop, that is, adding a feedback module to reduce the primary side loop current when the equivalent input voltage remains constant under the same angular vibration signal input to avoid saturation of the noise matching transformer core.

[0046] like Figure 1 As shown, the feedback module 120 may include a first feedback resistor R G and the second feedback resistor R F .

[0047] The first feedback resistor R G The first end of the primary coil 110 and the second end of the second feedback resistor R F The first end of the first feedback resistor R G The second end of the feedback resistor R F The second end of is electrically connected to the output end of the first active amplifier 140 .

[0048] According to Kirchhoff's voltage law, Figure 1 The primary side loop where the primary coil 110 is located satisfies the voltage equation shown in formula (1).

[0049] (1);

[0050] in, It is the output voltage generated by the sensitive element of the magnetic fluid angular vibration sensor when it is excited by vibration. is the voltage across the first feedback resistor, L1 is the equivalent inductance of the primary side where the primary coil is located, is the equivalent input current of the primary side loop where the primary coil is located, j is the imaginary unit, and ω is the frequency of the alternating current.

[0051] Applying Kirchhoff's current law at the node between the feedback module and the primary side loop where the primary coil is located, the equivalent input current of the primary side loop where the primary coil is located is Satisfies formula (2).

[0052] (2);

[0053] in, is the resistance of the first feedback resistor, is the resistance of the second feedback resistor, V out is the output voltage of the first active amplifier.

[0054] The voltage equation of the forward path of the active noise matching transformer 100 is shown in formula (3).

[0055] (3);

[0056] in, is the transimpedance gain, , It reflects the relationship between the output voltage of the first active amplifier and the equivalent input current of the primary side loop, n2 is the turns ratio of the secondary coil to the primary coil, and K1 is the voltage gain coefficient of the first active amplifier.

[0057] According to formula (2), the voltage across the first feedback resistor shown in formula (4) can be obtained .

[0058] (4).

[0059] Substituting formula (4) into formula (1) yields formula (5).

[0060] (5).

[0061] From formula (5), the equivalent input impedance shown in formula (6) can be obtained: .

[0062] (6).

[0063] From formula (3) and formula (5), the system voltage gain shown in formula (7) can be obtained.

[0064] (7).

[0065] According to formula (7), the first target transfer function G1(s) of the system voltage gain of the active noise matching transformer shown in formula (8) can be obtained.

[0066] (8).

[0067] Where s is a complex variable.

[0068] According to formula (8), Figure 1 The first target transfer function G1(s) of the system voltage gain of the active noise matching transformer 100 is obtained by the following operation: the first feedback resistor R G Resistance and the second feedback resistor R F Resistance After adding, the first term is obtained by multiplying the inductance L1 of the primary coil 110, the turns ratio n2 of the secondary coil 130 to the primary coil 110, and the voltage gain coefficient K1 of the first active amplifier 140 in sequence. G Resistance and the second feedback resistor R F Resistance Multiply them together to get the second term. G Resistance and source resistance R S Resistance Multiply them together to get the third term. F Resistance and source resistance R S Resistance The fourth term is obtained by multiplying the turns ratio n2 of the secondary coil 130 to the primary coil 110 with the voltage gain coefficient K1 of the first active amplifier 140 and the first feedback resistor R G Resistance The product of the first feedback resistor R G Resistance , the second feedback resistor R F Resistance After addition, the fifth term is obtained by multiplying the inductance L1 of the primary coil 110. According to the first term, the second term, the third term, the fourth term and the fifth term, the first target transfer function G1(s) is obtained.

[0069] For example, the second term, the third term, the fourth term, and the fifth term may be added together to obtain a sum value, and the first term may be divided by the sum value to obtain the first target transfer function G1(s).

[0070] When the feedback module 120 in the active noise matching transformer 100 is removed and the second end of the primary coil 110 is grounded, the transfer function G0(s) of the system voltage gain is shown in Formula (9).

[0071] (9).

[0072] According to an embodiment of the present invention, the number of turns of the primary winding of the noise matching transformer (i.e., the number of turns of the primary coil) remains unchanged, and the number of turns of the secondary winding of the noise matching transformer (i.e., the number of turns of the secondary coil) is changed to change the winding turns ratio. Zero-pole matching is performed on Equations (8) and (9) so that the transfer function coefficient when the feedback module in the active noise matching transformer is removed is the same as the transfer function coefficient of the active noise matching transformer including the feedback module, and the corresponding zeros and poles are the same.

[0073] While the core of the active noise matching transformer remains unchanged and the primary winding remains unchanged at 1 turn, that is, the inductance value of the equivalent inductance on the primary side where the primary coil is located remains unchanged, the turns ratio of the secondary coil 130 to the primary coil 110 is changed from n1 to n2, and zero-pole matching is performed on formulas (8) and (9), resulting in the conclusions shown in formulas (10) to (12).

[0074] (10).

[0075] (11).

[0076] (12).

[0077] Formula (11) shows that the resistance of the second feedback resistor is configured based on the turns ratio of the secondary coil to the primary coil, the resistance of the source resistor, and the voltage gain coefficient of the first active amplifier. For example, the resistance of the second feedback resistor can be configured based on the turns ratio of the secondary coil to the primary coil after the active noise matching transformer includes the feedback module, the resistance of the source resistor, and the voltage gain coefficient of the first active amplifier. The source resistor is the equivalent resistance of the sensor sensitive element included in the magnetic fluid angular vibration sensor.

[0078] Formula (12) shows that the resistance of the first feedback resistor is configured based on the turns ratio of the secondary winding to the primary winding and the resistance of the source resistor. For example, the resistance of the first feedback resistor can be configured based on the turns ratio of the secondary winding to the primary winding before and after the active noise matching transformer is added to the feedback module, as well as the resistance of the source resistor.

[0079] According to an embodiment of the present invention, an active noise matching transformer for a magnetic fluid angular vibration sensor is provided. By adjusting the turns ratio of the secondary coil to the primary coil and adding a feedback resistor to form a feedback loop, the equivalent input impedance of the primary side can be increased while ensuring that the system voltage gain of the active noise matching transformer remains unchanged. This correspondingly achieves input current attenuation on the primary side and avoids saturation of the noise matching transformer core.

[0080] Figure 2 FIG. 4 is a schematic structural diagram of an active noise matching transformer according to another embodiment of the present invention.

[0081] like Figure 2 As shown, the equivalent voltage noise of the sensitive element 1011 of the magnetic fluid angular vibration sensor 101 is e s The equivalent input voltage noise and current noise of the first active amplifier 140 are e n and i n The PSD of the equivalent input voltage of the first active amplifier 140 is , the PSD of the equivalent input current of the first active amplifier 140 is The source resistance of the sensor sensitive element 1011 is Rs. The second feedback resistor R F and the first feedback resistor R G The equivalent thermal noise voltage is expressed as e f and e g The noise figure of the active noise matching transformer 100 is ,in is the first feedback resistor R G and the second feedback resistor R F The equivalent resistance R in parallel p The resistance value, .

[0082] Figure 3 FIG. 4 shows a structural diagram of an active noise matching transformer according to another embodiment of the present invention.

[0083] like Figure 3 As shown, the active noise matching transformer 100 may include a primary coil 110 , a feedback module 120 , a secondary coil 130 and a first active amplifier 140 .

[0084] The feedback module 120 may include a first feedback resistor R G , the second feedback resistor R F and a second active amplifier 121 .

[0085] Among them, the first feedback resistor R G The first end of the primary coil 110 and the second end of the second feedback resistor R F The first end of the first feedback resistor R G The second end of the feedback resistor R F The second end of the second active amplifier 121 is electrically connected to the output end of the second active amplifier 121. The two input ends of the second active amplifier 121 are electrically connected to the two ends of the secondary coil 130 respectively.

[0086] According to an embodiment of the present invention, by adjusting the voltage gain of the second active amplifier 121 included in the feedback module 120, the equivalent input impedance can be adjusted to achieve control of the input current and system voltage gain. For example, increasing the voltage gain of the second active amplifier 121 will reduce the system voltage gain and significantly attenuate the input current, thereby preventing transformer core saturation.

[0087] In the case where the feedback module includes a first feedback resistor, a second feedback resistor, and a second active amplifier, a second target transfer function G2(s) of the system voltage gain of the active noise matching transformer can be obtained according to formula (13).

[0088] (13).

[0089] Wherein, K2 is the voltage gain coefficient of the second active amplifier.

[0090] According to formula (13), Figure 3 The second target transfer function of the system voltage gain of the active noise matching transformer 100 is obtained by the following operation: the first feedback resistor R G Resistance and the second feedback resistor R F Resistance After adding, the first term is obtained by multiplying the inductance L1 of the primary coil 110, the turns ratio n2 of the secondary coil 130 to the primary coil 110, and the voltage gain coefficient K1 of the first active amplifier 140 in sequence. G Resistance and the second feedback resistor R F Resistance Multiply them together to get the second term. G Resistance and source resistance R S Resistance Multiply them together to get the third term. F Resistance and source resistance R S Resistance Multiplying the turns ratio n2 of the secondary coil 130 to the primary coil 110 with the voltage gain coefficient K2 of the second active amplifier 121 and the first feedback resistor R G Resistance The product of the first feedback resistor R G Resistance , the second feedback resistor R F Resistance After addition, the fifth term is obtained by multiplying the inductance L1 of the primary coil 110. According to the first term, the second term, the third term, the fourth term and the fifth term, the second target transfer function G2(s) is obtained.

[0091] For example, the second term, the third term, the fourth term, and the fifth term may be added together to obtain a sum value, and the first term may be divided by the sum value to obtain the second target transfer function G2(s).

[0092] According to an embodiment of the present invention, the number of turns of the primary winding of the noise matching transformer (i.e., the number of turns of the primary coil) remains unchanged, and the number of turns of the secondary winding of the noise matching transformer (i.e., the number of turns of the secondary coil) is changed to change the winding turns ratio. Zero-pole matching is performed on Equations (9) and (13) so that the transfer function coefficient when the feedback module in the active noise matching transformer is removed is the same as the transfer function coefficient of the active noise matching transformer including the feedback module, and the corresponding zeros and poles are the same.

[0093] When the core of the active noise matching transformer remains unchanged and the primary winding remains unchanged at 1 turn, that is, the inductance value of the equivalent inductance on the primary side where the primary coil is located remains unchanged, the turns ratio of the secondary coil 130 to the primary coil 110 is changed from n1 to n2, and zero-pole matching is performed on formulas (9) and (13), the conclusions shown in formulas (14) and (15) are obtained.

[0094] (14).

[0095] (15).

[0096] It can be seen from formula (14) that the resistance of the second feedback resistor is determined according to the turns ratio of the secondary coil to the primary coil after the active noise matching transformer including the feedback module, the resistance of the source resistor, and the voltage gain coefficient of the second active amplifier, wherein the source resistor is the equivalent resistance of the sensor sensitive element included in the magnetic fluid angular vibration sensor.

[0097] Formula (15) shows that the resistance of the first feedback resistor is configured based on the turns ratio of the secondary winding to the primary winding and the resistance of the source resistor. For example, the resistance of the first feedback resistor can be configured based on the turns ratio of the secondary winding to the primary winding before and after the active noise matching transformer is added to the feedback module, as well as the resistance of the source resistor.

[0098] According to an embodiment of the present invention, the number of turns of the secondary coil 130 is an integer multiple of the target number of turns.

[0099] According to the embodiment of the present invention, the target number of turns can be selected according to actual conditions and is not limited here.

[0100] For example, the number of turns of the secondary coil 130 may be 2, 3, or 5 times the target number of turns.

[0101] For example, if the feedback module 120 in the active noise matching transformer 100 is removed and the second end of the primary coil 110 is grounded, the number of turns of the secondary coil 130 can be the target number of turns. In this case, n2 is an integer multiple of n1. For example, n2 can be 5 times n1. The number of turns of the primary coil can be selected based on actual conditions and is not limited here. For example, the number of turns of the primary coil can be 1, 2, 3, 4, 5, etc.

[0102] The active noise matching transformer provided in the embodiment of the present invention solves the technical problem of low-frequency harmonic distortion through hardware circuit innovation without replacing the core material of the noise matching transformer. Its current suppression mechanism provides a universal circuit design paradigm for solving the magnetic saturation distortion problem of similar transformers.

[0103] The active noise matching transformer provided in an embodiment of the present invention performs circuit topology optimization to address the transformer core saturation problem in the low-frequency range (e.g., 0-5 Hz) and provides the optimal turns ratio and minimum noise figure for the active noise matching transformer.

[0104] It will be understood by those skilled in the art that the features described in the various embodiments of the present invention may be combined and / or coupled in various ways, even if such combinations or couplings are not explicitly described in the present invention. In particular, the features described in the various embodiments of the present invention may be combined and / or coupled in various ways without departing from the spirit and teachings of the present invention. All such combinations and / or couplings fall within the scope of the present invention.

[0105] The above describes embodiments of the present invention. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of the present invention. Although each embodiment has been described separately above, this does not mean that the measures in each embodiment cannot be advantageously used in combination. Without departing from the scope of the present invention, those skilled in the art may make various substitutions and modifications, which should all fall within the scope of the present invention.

Claims

1. An active noise matching transformer, characterized in that: include: a primary coil, a feedback module, a secondary coil, and a first active amplifier; Wherein, the first end of the primary coil is electrically connected to the output end of the magnetic fluid angular vibration sensor, the second end of the primary coil is electrically connected to the first end of the feedback module, and the primary coil is electromagnetically coupled to the secondary coil; Two ends of the secondary coil are electrically connected to two input ends of the first active amplifier respectively; The second end of the feedback module receives the output signal of the secondary side loop where the secondary coil is located, and the third end of the feedback module is grounded; The number of turns of the secondary coil and the equivalent resistance of the feedback module are configured so that, when the system voltage gain of the active noise matching transformer is equal to the target voltage gain, the equivalent input impedance of the primary-side loop in which the primary coil is located is equal to the target impedance. The target voltage gain is the system voltage gain when the active noise matching transformer does not include the feedback module. The target voltage gain is calculated when the equivalent output resistance of the loop in which the primary coil, the secondary coil, and the magnetic fluid angular vibration sensor are located is equal to the optimal source resistance of the first active amplifier. The optimal source resistance of the first active amplifier is calculated based on the power spectral density of the equivalent input voltage and the power spectral density of the equivalent input current of the first active amplifier. The feedback module includes a first feedback resistor and a second feedback resistor; a first end of the first feedback resistor is electrically connected to the second end of the primary coil and the first end of the second feedback resistor, and a second end of the first feedback resistor is grounded; a second end of the second feedback resistor is electrically connected to the output end of the first active amplifier; In the case where the feedback module includes a first feedback resistor and a second feedback resistor, a first target transfer function of the system voltage gain of the active noise matching transformer is obtained according to the following operations: adding the resistance of the first feedback resistor and the resistance of the second feedback resistor, and multiplying the sum by the inductance of the primary coil, the turns ratio of the secondary coil to the primary coil, and the voltage gain coefficient of the first active amplifier in sequence to obtain a first term; multiplying the resistance of the first feedback resistor and the resistance of the second feedback resistor to obtain a second term; multiplying the resistance of the first feedback resistor and the resistance of the source resistor to obtain a third term; multiplying the resistance of the second feedback resistor and the resistance of the source resistor to obtain a fourth term; adding the product of the turns ratio of the secondary coil to the primary coil, the voltage gain coefficient of the first active amplifier, and the resistance of the first feedback resistor, the resistance of the first feedback resistor, and the resistance of the second feedback resistor, and multiplying the sum by the inductance of the primary coil to obtain a fifth term; and obtaining the first target transfer function according to the first, second, third, fourth, and fifth terms. Alternatively, the feedback module includes a first feedback resistor, a second feedback resistor and a second active amplifier; the first end of the first feedback resistor is electrically connected to the second end of the primary coil and the first end of the second feedback resistor, and the second end of the first feedback resistor is grounded; the second end of the second feedback resistor is electrically connected to the output end of the second active amplifier; and the two input ends of the second active amplifier are respectively electrically connected to the two ends of the secondary coil.

2. The active noise matching transformer according to claim 1, characterized in that: When the feedback module includes a first feedback resistor and a second feedback resistor, the resistance of the second feedback resistor is configured based on the turns ratio of the secondary coil to the primary coil, the resistance of the source resistor, and the voltage gain coefficient of the first active amplifier, wherein the source resistor is the equivalent resistance of the sensor sensitive element included in the magnetic fluid angular vibration sensor.

3. The active noise matching transformer according to claim 2, characterized in that: The resistance of the first feedback resistor is configured according to the turns ratio of the secondary coil to the primary coil and the resistance of the source resistor.

4. The active noise matching transformer according to claim 1, characterized in that: When the feedback module includes a first feedback resistor, a second feedback resistor, and a second active amplifier, the resistance of the second feedback resistor is determined based on the turns ratio of the secondary coil to the primary coil, the resistance of the source resistor, and the voltage gain coefficient of the second active amplifier, wherein the source resistor is the equivalent resistance of the sensor sensitive element included in the magnetic fluid angular vibration sensor.

5. The active noise matching transformer according to claim 4, characterized in that: The resistance of the first feedback resistor is configured according to the turns ratio of the secondary coil to the primary coil and the resistance of the source resistor.

6. The active noise matching transformer according to claim 5, characterized in that: The second target transfer function of the system voltage gain of the active noise matching transformer is obtained according to the following operation: Adding the resistance of the first feedback resistor and the resistance of the second feedback resistor, and multiplying the sum by the inductance of the primary coil, the turns ratio of the secondary coil to the primary coil, and the voltage gain coefficient of the first active amplifier in sequence to obtain a first term; Multiplying the resistance of the first feedback resistor and the resistance of the second feedback resistor to obtain a second term; Multiplying the resistance of the first feedback resistor and the resistance of the source resistor to obtain a third term; Multiplying the resistance of the second feedback resistor and the resistance of the source resistor to obtain a fourth term; A fifth term is obtained by adding the product of the turns ratio of the secondary coil to the primary coil, the voltage gain coefficient of the second active amplifier, and the resistance value of the first feedback resistor, the resistance value of the first feedback resistor, and the resistance value of the second feedback resistor, and then multiplying the result by the inductance value of the primary coil; The second target transfer function is obtained according to the first term, the second term, the third term, the fourth term and the fifth term.

7. The active noise matching transformer according to claim 3 or 5, characterized in that: The number of turns of the secondary coil is an integer multiple of the target number of turns.

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