Active noise matching transformer

Abstract

The invention provides an active noise matching transformer which can be applied to the technical field of transformers. The active noise matching transformer comprises a primary coil, a feedback module, a secondary coil and a first active amplifier, the first end of the primary coil is electrically connected with the output end of the magnetofluid angular vibration sensor, the second end of the primary coil is electrically connected with the first end of the feedback module, and the primary coil is electromagnetically coupled with the secondary coil; two ends of the secondary coil are electrically connected with two input ends of the first active amplifier respectively; the second end of the feedback module receives an output signal of a 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 value of the feedback module are configured to enable the equivalent input impedance of the primary side loop where the primary coil is located to be the target impedance under the condition that the system voltage gain of the active noise matching transformer is equal to the target voltage gain.

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] The magnetohydrodynamic angular vibration sensor belongs to a high-frequency angular vibration sensor, and has characteristics such as high sensitivity, wide working range, low noise, and small volume. The magnetohydrodynamic angular vibration sensor is based on the principle of conductive fluid dynamics. When an external vibration signal is input, the conductive fluid moves relative to each other in a magnetic field, generating an induced electromotive force, thereby realizing the detection of the angular vibration signal.

[0003] The angular vibration signal detected by the magnetohydrodynamic angular vibration sensor is weak. By adding a noise matching transformer between the sensitive element of the sensor and the active amplifier to form a noise matching network, the extraction of the high-frequency angular vibration signal is realized.

[0004] However, in practical applications, the noise matching transformer has harmonic distortion in the low-frequency band, for example, in the frequency band less than 5 Hz, specifically manifested as output asymmetry, waveform distortion, etc., resulting in low working efficiency and performance degradation of the magnetohydrodynamic 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 magnetohydrodynamic 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; both ends of the secondary coil are respectively electrically connected to 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 value of the feedback module are configured to make the equivalent input impedance of the primary side loop where the primary coil is located be the target impedance when the system voltage gain of the active noise matching transformer is equal to the target voltage gain, wherein the target voltage gain is the system voltage gain of the active noise matching transformer when the feedback module is not included, and the target voltage gain is calculated under the condition that the equivalent output resistance of the loop where the primary coil, the secondary coil, and the magnetohydrodynamic angular vibration sensor are located is equal to the optimal source resistance of the first active amplifier, and the optimal source resistance of the first active amplifier is calculated according to the power spectral density of the equivalent input voltage of the first active amplifier and the power spectral density of the equivalent input current of the first active amplifier.

[0007] For example, the above 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 value of the second feedback resistor is configured according to the turns ratio of the secondary coil to the primary coil, the resistance value 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 magnetohydrodynamic angular vibration sensor.

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

[0010] For example, the first target transfer function of the system voltage gain of the above active noise matching transformer is obtained according to the following operations: after adding the resistance values of the first feedback resistor and the second feedback resistor, multiply them successively by the inductance value 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 the first term; multiply the resistance values of the first feedback resistor and the second feedback resistor to obtain the second term; multiply the resistance values of the first feedback resistor and the source resistor to obtain the third term; multiply the resistance values of the second feedback resistor and the source resistor to obtain the fourth term; after 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 value of the first feedback resistor, the resistance value of the first feedback resistor, and the resistance value of the second feedback resistor, multiply it by the inductance value of the primary coil to obtain the fifth term; according to the first term, the second term, the third term, the fourth term, and the fifth term, obtain the first target transfer function.

[0011] For example, the above 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; 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 value of the second feedback resistor described above is determined based on the turns ratio of the secondary coil to the primary coil, the resistance value of the source resistor, and the voltage gain coefficient of the second active amplifier, where the source resistor is the equivalent resistance of the sensor sensitive element included in the magnetohydrodynamic angular vibration sensor.

[0013] For example, the resistance value of the first feedback resistor described above is configured based on the turns ratio of the secondary coil to the primary coil and the resistance value of the source resistor.

[0014] For example, the second target transfer function of the system voltage gain of the active noise matching transformer described above is obtained through the following operations: after adding the resistance values of the first feedback resistor and the second feedback resistor, multiply them successively by the inductance value 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 the first term; multiply the resistance values of the first feedback resistor and the second feedback resistor to obtain the second term; multiply the resistance value of the first feedback resistor and the resistance value of the source resistor to obtain the third term; multiply the resistance value of the second feedback resistor and the resistance value of the source resistor to obtain the fourth term; after 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, multiply it by the inductance value of the primary coil to obtain the fifth term; based on the first term, the second term, the third term, the fourth term, and the fifth term, obtain the second target transfer function.

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

[0016] According to the active noise matching transformer provided by the embodiment of the present invention, by electrically connecting the first end of the primary coil to the output end of the magnetohydrodynamic angular vibration sensor, electrically connecting the second end of the primary coil to the first end of the feedback module, electromagnetic coupling between the primary coil and the secondary coil, electrically connecting both ends of the secondary coil to two input ends of the first active amplifier respectively, receiving the output signal of the secondary side loop where the secondary coil is located at the second end of the feedback module, and grounding the third end of the feedback module, the number of turns of the secondary coil and the equivalent resistance value of the feedback module can make the equivalent input impedance of the primary side loop where the primary coil is located be the target impedance when 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 value of the feedback module, it is possible to increase the equivalent input impedance of the primary side loop while keeping the system voltage gain unchanged, corresponding to a decrease in the current of the primary side loop to prevent magnetic core saturation, and thus solve the problem of harmonic distortion in the low-frequency band, and improve the working efficiency and performance of the magnetohydrodynamic angular vibration sensor in the low-frequency band.

[0017] Meanwhile, since the target voltage gain is the system voltage gain of the active noise matching transformer without the feedback module, the target voltage gain is calculated under the condition that the equivalent output resistance of the loop where the primary coil, the secondary coil, and the magnetohydrodynamic 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 first active amplifier corresponding to the target voltage gain operates in the optimal noise figure state, that is, the noise matching state. The output signal output by the first active amplifier is less affected by the noise voltage, and the output signal output by the first active amplifier is more accurate. When adjusting the number of turns of the secondary coil and the equivalent resistance value of the feedback module while keeping the system voltage gain of the active noise matching transformer equal to the target voltage gain, it is possible to make the output signal output by the first active amplifier less affected by the noise voltage, the output signal output by the first active amplifier more accurate, the signal range of the output signal unchanged, and at the same time reduce the current of the corresponding primary side loop to prevent the magnetic core from saturating. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Through the following description of the embodiments of the present invention with reference to the accompanying drawings, the above content and other objects, features, and advantages of the present invention will become clearer.

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

[0020] Figure 2 The structural schematic diagram of the active noise matching transformer according to another embodiment of the present invention is shown.

[0021] Figure 3 The structural schematic diagram of the active noise matching transformer according to still another embodiment of the present invention is shown. DETAILED DESCRIPTION OF THE EMBODIMENTS

[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 and are not intended to limit the scope of the present invention. In the following detailed description, for the sake of explanation, many specific details are set forth to provide a comprehensive understanding of the embodiments of the present invention. However, obviously, one or more embodiments can also be implemented without these specific details. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessarily confusing the concepts of the present invention.

[0023] The terms used herein are for describing specific embodiments only and are not intended to limit the present invention. The terms "including", "comprising", etc. used herein indicate the presence of the described 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] In cases where expressions similar to "at least one of A, B, and C, etc." are used, generally, it should be interpreted according to 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 not be limited to, a system having only A, only B, only C, having A and B, having A and C, having B and C, and / or having A, B, and C, etc.).

[0026] The related technology realizes the extraction of high-frequency angular vibration signals by adding a noise matching transformer between the sensitive element of the sensor and the active amplifier to form a noise matching network. However, in practical applications, the noise matching transformer has harmonic distortion in the low-frequency band, for example, in the frequency band less than 5 Hz, specifically manifested as output asymmetry, waveform distortion, etc. Analyzing the reason for the harmonic distortion is that the input impedance value of the primary circuit side of the noise matching transformer is small in the low-frequency band, resulting in a large primary circuit current, which in turn causes the magnetic core of the noise matching transformer to saturate, leading to the non-linear characteristics of the noise matching transformer. In the saturated state, the waveform of the output signal is distorted and becomes sharp or irregular, and these irregular components will be manifested as harmonics. In spectral analysis, in addition to the fundamental frequency signal, harmonic components of integer multiples of the frequency can also be seen, such as the second harmonic, the third harmonic, etc. These harmonics will cause an additional burden on other devices in the circuit and affect the normal operation of the sensor. Running in the saturated state for a long time may also cause sensor damage and a decrease in the system test efficiency. Therefore, solving the problem of harmonic distortion of this active noise matching transformer in the low-frequency domain and improving the working efficiency of the sensor in the low-frequency domain are particularly important for improving the performance of the sensor.

[0027] Existing technical solutions to solve core saturation include increasing the air gap and selecting appropriate core materials. By introducing an air gap in the core to increase the total length of the magnetic flux path and delay the saturation phenomenon, the magnetic permeability of the core will be significantly reduced, resulting in a decrease in the inductance of the noise matching transformer winding and still possibly causing non-linear distortion of the output signal. Another solution is to select a core material with a higher saturation magnetic flux density, which can increase the operating range of the noise matching transformer. However, the sensor core mentioned in the present invention is a soft magnetic material with high magnetic permeability, and no replaceable core material has been found yet.

[0028] In view of this, embodiments of the present invention provide an active noise matching transformer, which can be applied to the field of transformers. Considering from the circuit design, by changing the circuit structure, the primary side current of the noise matching transformer is reduced to avoid saturation of the transformer core in the low-frequency domain and avoid harmonic distortion.

[0029] The active noise matching transformer applicable to the magneto-fluid angular vibration sensor provided by the present invention proposes an improvement scheme based on circuit topology optimization for the technical defect of harmonic distortion existing in the magneto-fluid angular vibration sensor 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 turn ratio of the windings on both sides of the noise matching transformer, and introducing a feedback resistor network to form a dynamic compensation loop. On the premise of maintaining the constant voltage gain of the system, by adjusting the number of turns of the secondary coil and the equivalent resistance value of the feedback module, the equivalent input impedance of the primary side is adjusted, effectively reducing the input current of the primary side, and fundamentally solving the problem of output waveform distortion caused by the saturation of the noise matching transformer core. Among them, the noise matching transformer includes a primary coil and a secondary coil.

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

[0031] As Figure 1 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] The first end of the primary coil 110 may be electrically connected to the output end of the magneto-fluid angular vibration sensor 101. The second end of the primary coil 110 may be electrically connected to the first end of the feedback module 120. The primary coil 110 may be electromagnetically coupled to the secondary coil 130.

[0033] Both ends of the secondary coil 130 can be electrically connected to two input ends of the first active amplifier 140 respectively. 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. Or, 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 value of the feedback module 120 are configured such 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 where the primary coil 110 is located is the target impedance. Among them, the target voltage gain is the system voltage gain when the feedback module is not included in the active noise matching transformer 100, and the target voltage gain is calculated under the condition that the equivalent output resistance of the loop where the primary coil, the secondary coil, and the magnetohydrodynamic 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 of the first active amplifier and the power spectral density of the equivalent input current of the first active amplifier. At this time, 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] In Figure 1 the sensitive element 1011 of the magnetohydrodynamic angular vibration sensor 101 outputs a signal after being amplified twice by the active noise matching transformer 100. The equivalent resistance of the sensitive element 1011 of the magnetohydrodynamic angular vibration sensor 101 is the source resistance R S .

[0037] According to the active noise matching transformer provided by the embodiments of the present invention, by electrically connecting the first end of the primary coil to the output end of the magnetohydrodynamic angular vibration sensor, the second end of the primary coil to the first end of the feedback module, the primary coil being electromagnetically coupled to the secondary coil, the two ends of the secondary coil being respectively electrically connected to the two input ends of the first active amplifier, the second end of the feedback module receiving the output signal of the secondary side loop where the secondary coil is located, and the third end of the feedback module being grounded, the number of turns of the secondary coil and the equivalent resistance value of the feedback module can make the equivalent input impedance of the primary side loop where the primary coil is located be the target impedance when 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 value of the feedback module, it is possible to increase the equivalent input impedance of the primary side loop while keeping the system voltage gain unchanged, corresponding to a decrease in the current of the primary side loop, so as to prevent magnetic core saturation, and further solve the problem of harmonic distortion in its low-frequency band, and improve the working efficiency and performance of the magnetohydrodynamic angular vibration sensor in the low-frequency band.

[0038] At the same time, since the target voltage gain is the system voltage gain of the active noise matching transformer without the feedback module, the target voltage gain is calculated under the condition that the equivalent output resistance of the loop where the primary coil, the secondary coil, and the magnetohydrodynamic angular vibration sensor are located is equal to the optimal source resistance of the first active amplifier, and 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 first active amplifier corresponding to the target voltage gain operates in the optimal noise factor state, that is, the noise matching state. The output signal output by the first active amplifier is less affected by the noise voltage, and the output signal output by the first active amplifier is relatively accurate. When adjusting the number of turns of the secondary coil and the equivalent resistance value of the feedback module while keeping the system voltage gain of the active noise matching transformer equal to the target voltage gain, it is possible to make the output signal output by the first active amplifier less affected by the noise voltage, the output signal output by the first active amplifier is relatively accurate, the signal range of the output signal remains unchanged, and at the same time, the current of the corresponding primary side loop is reduced to prevent magnetic core saturation.

[0039] According to the active noise matching transformer provided by the embodiments of the present invention, it is possible to change the number of turns of the secondary coil while inputting the same angular vibration signal to the active noise matching transformer and without changing the number of turns of the winding in the primary coil, and at the same time adding a feedback module, so as to increase the equivalent input impedance of the primary side while keeping the system voltage gain unchanged, corresponding to a decrease in the primary side current. By based on the circuit characteristics of the active noise matching transformer and adjusting the circuit structure, it is possible to reduce the primary side current of the noise matching transformer to prevent magnetic core saturation, and further solve the problem of harmonic distortion in its low-frequency band.

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

[0041] The active noise matching transformer provided according to an embodiment of the present invention has a simple circuit design and low required cost, and has obvious advantages compared with selecting 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 magnetohydrodynamic angular vibration sensor 101 can be e s , and 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 , and 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 magnetohydrodynamic angular vibration sensor 101, and the optimal source resistance of the first active amplifier 140 is equal to the source resistance R S , the first active amplifier 140 operates in the optimal noise coefficient state, which is called the noise matching state. When the optimal source resistance of the first active amplifier 140 is not equal to the source resistance R S , a transformer can be added between the sensitive element 1011 of the magnetohydrodynamic angular vibration sensor 101 and the first active amplifier 140 to make the first active amplifier 140 operate in the optimal noise coefficient state. That is, when the feedback module 120 in the active noise matching transformer 100 is removed, the active noise matching transformer 100 does not include the feedback module 120, and the second end of the primary coil 110 is grounded, the equivalent output resistance of the loop where the primary coil 110, the secondary coil 130, and the magnetohydrodynamic angular vibration sensor 101 are located increases by the square of the turns ratio, so that the equivalent output resistance of the loop where the primary coil 110, the secondary coil 130, and the magnetohydrodynamic angular vibration sensor 101 are located is equal to the optimal source resistance of the first active amplifier 140, realizing noise matching to achieve the minimum noise coefficient. Among them, 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 value.

[0044] When the active noise matching transformer 100 does not include the feedback module 120, the turns ratio of the secondary coil 130 to the primary coil 110 is n1, and n1 is equal to the optimal turns ratio of the transformer corresponding to the minimum noise coefficient, . The primary side winding of the noise matching transformer has one turn, and the turns ratio is the number of turns of the secondary side winding. The active noise matching transformer without the feedback module has a small equivalent input impedance in the low frequency range. Under the input of the same angular vibration signal, the equivalent input voltage remains constant, resulting in a large primary side loop current, which easily causes the magnetic core saturation of the noise matching transformer and leads to distortion and distortion of the output waveform.

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

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

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

[0048] Based on Kirchhoff's voltage law, it can be known that Figure 1 the primary side loop where the primary coil 110 is located in

[0049] (1);

[0050] Among them, is the output voltage generated by the sensitive element of the magnetohydrodynamic angular vibration sensor under vibration excitation, 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] Apply Kirchhoff's current law at the node of 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 satisfies Equation (2).

[0052] (2);

[0053] where is the resistance value of the first feedback resistor, is the resistance value 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 Equation (3).

[0055] (3);

[0056] where is the transimpedance gain, , 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 Equation (2), the voltage across the first feedback resistor shown in Equation (4) can be obtained .

[0058] (4).

[0059] Substitute Equation (4) into Equation (1) to obtain Equation (5).

[0060] (5).

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

[0062] (6).

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

[0064] (7).

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

[0066] (8).

[0067] Here, 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 the addition, the fifth term is obtained by multiplying the inductance value 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 as shown in formula (9).

[0071] (9).

[0072] According to an embodiment of the present invention, while keeping the number of turns of the primary winding of the noise matching transformer (i.e., the number of turns of the winding of the primary coil) unchanged, by changing the number of turns of the secondary winding of the noise matching transformer (i.e., the number of turns of the winding of the secondary coil), the turns ratio can be changed. Zero-pole matching is performed on formula (8) and formula (9) to make the transfer function coefficient when the feedback module in the active noise matching transformer is removed the same as the transfer function coefficient of the active noise matching transformer including the feedback module, and the corresponding zero-poles are the same.

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

[0074] (10).

[0075] (11).

[0076] (12).

[0077] It can be seen from formula (11) that the resistance value of the second feedback resistor is configured according to the turns ratio of the secondary coil to the primary coil, the resistance value of the source resistor, and the voltage gain coefficient of the first active amplifier. For example, the resistance value of the second feedback resistor can be configured according to the turns ratio of the secondary coil to the primary coil, the resistance value of the source resistor, and the voltage gain coefficient of the first active amplifier after the active noise matching transformer includes the feedback module. The source resistor is the equivalent resistance of the sensor sensitive element included in the magnetohydrodynamic angular vibration sensor.

[0078] It can be seen from formula (12) that the resistance value of the first feedback resistor is configured according to the turns ratio of the secondary coil to the primary coil and the resistance value of the source resistor. For example, the resistance value of the first feedback resistor can be configured according to the turns ratio of the secondary coil to the primary coil before and after the active noise matching transformer adds the feedback module and the resistance value of the source resistor.

[0079] According to the active noise matching transformer applicable to the magnetohydrodynamic angular vibration sensor provided by the embodiment of the present invention, by adjusting the turns ratio of the secondary coil to the primary coil and adding a feedback resistor to form a feedback loop, it is possible to increase the equivalent input impedance on the primary side while ensuring that the system voltage gain of the active noise matching transformer remains unchanged, correspondingly achieving attenuation of the input current on the primary side and avoiding saturation of the magnetic core of the noise matching transformer.

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

[0081] As Figure 2 shown, the equivalent voltage noise of the sensitive element 1011 of the magneto - fluid angular vibration sensor 101 is e s , and 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 , and 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 equivalent thermal noise voltages of the second feedback resistor R F and the first feedback resistor R G are respectively expressed as e f and e g . The noise figure of the active noise - matching transformer 100 is , where is the resistance value of the equivalent resistor R G formed by the parallel connection of the first feedback resistor R F and the second feedback resistor R p , .

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

[0083] As Figure 3 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 , a second feedback resistor R F , and a second active amplifier 121.

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

[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 the control of the input current and the 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, avoiding the saturation of the transformer core.

[0087] When the feedback module includes a first feedback resistor, a second feedback resistor, and a second active amplifier, the 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] It can be known from formula (13) that Figure 3 the second target transfer function of the system voltage gain of the active noise matching transformer 100 shown is obtained according to the following operations: After adding the resistance values of the first feedback resistor R G and the second feedback resistor R and multiplying successively by the inductance value 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, the first term is obtained. Multiply the resistance values of the first feedback resistor R F and the second feedback resistor R to obtain the second term. Multiply the resistance values of the first feedback resistor R G and the source resistor R to obtain the third term. Multiply the resistance values of the second feedback resistor R F and the source resistor R to obtain the fourth term. Multiply the product of the turns ratio n2 of the secondary coil 130 to the primary coil 110, the voltage gain coefficient K2 of the second active amplifier 121, and the resistance value of the first feedback resistor R G by the resistance value of the first feedback resistor R and the resistance value of the second feedback resistor R S and the resistance value of the source resistor R and the resistance value of the second feedback resistor R F and the resistance value of the source resistor R and the resistance value of the source resistor R S and the resistance value of the first feedback resistor R and the resistance value of the second feedback resistor R G and the resistance value of the first feedback resistor R and the resistance value of the first feedback resistor R G and the resistance value of the second feedback resistor R and the resistance value of the second feedback resistor R F and the resistance value of the second feedback resistor R After addition, multiply by the inductance value L1 of the primary coil 110 to obtain the fifth term. According to the first term, the second term, the third term, the fourth term, and the fifth term, obtain the second target transfer function G2(s).

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

[0092] According to an embodiment of the present invention, while keeping the number of turns of the primary winding of the noise matching transformer (i.e., the number of turns of the primary coil) unchanged, by changing the number of turns of the secondary winding of the noise matching transformer (i.e., the number of turns of the secondary coil), the turns ratio can be changed. Perform zero-pole matching on formula (9) and formula (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 zero-poles are the same.

[0093] With the magnetic core of the active noise matching transformer unchanged and the primary winding remaining 1 turn unchanged, that is, the inductance value of the equivalent inductance on the primary side where the primary coil is located remains unchanged, change the turns ratio of the secondary coil 130 to the primary coil 110 from n1 to n2, and perform zero-pole matching on formula (9) and formula (13) to obtain the conclusions shown in formula (14) to formula (15).

[0094] (14).

[0095] (15).

[0096] It can be seen from formula (14) that the resistance value 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 includes the feedback module, the resistance value of the source resistor, and the voltage gain coefficient of the second active amplifier, where the source resistor is the equivalent resistance of the sensor sensitive element included in the magnetohydrodynamic angular vibration sensor.

[0097] It can be seen from formula (15) that the resistance value of the first feedback resistor is configured according to the turns ratio of the secondary coil to the primary coil and the resistance value of the source resistor. For example, the resistance value of the first feedback resistor can be configured according to the turns ratio of the secondary coil to the primary coil before and after the active noise matching transformer adds the feedback module and the resistance value 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 an embodiment of the present invention, the target number of turns can be selected according to actual situations and is not limited herein.

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

[0101] For example, in the case where 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. At this time, 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 according to the actual situation and is not limited herein. 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 by the embodiments of the present invention realizes the technical problem of solving low-frequency harmonic distortion without replacing the magnetic core material of the noise matching transformer through hardware circuit innovation, and its current suppression mechanism provides a general circuit design paradigm for the magnetic saturation distortion problem of transformers of the same type.

[0103] According to the active noise matching transformer provided by the embodiments of the present invention, circuit topology optimization is carried out to solve the problem of magnetic core saturation of the transformer in the low-frequency domain (e.g., 0 - 5 Hz), and the optimal turns ratio and the minimum noise coefficient of the corresponding active noise matching transformer can be given.

[0104] Those skilled in the art can understand that the features described in the various embodiments of the present invention can be combined and / or combined in various ways, even if such combinations or combinations are not explicitly described in the present invention. In particular, without departing from the spirit and teachings of the present invention, the features described in the various embodiments of the present invention can be combined and / or combined in various ways. All such combinations and / or combinations fall within the scope of the present invention.

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

Claims

1. An active noise matching transformer, characterized in that, Comprising: A primary coil, a feedback module, a secondary coil, and a first active amplifier; Wherein, a first end of the primary coil is electrically connected to an output end of a magnetohydrodynamic angular vibration sensor, a second end of the primary coil is electrically connected to a first end of the feedback module, and the primary coil is electromagnetically coupled with the secondary coil; Two ends of the secondary coil are respectively electrically connected to two input ends of the first active amplifier; A second end of the feedback module receives an output signal of a secondary side loop where the secondary coil is located, and a third end of the feedback module is grounded; Wherein, the number of turns of the secondary coil and the equivalent resistance value of the feedback module are configured such that when the system voltage gain of the active noise matching transformer is equal to a target voltage gain, the equivalent input impedance of a primary side loop where the primary coil is located is a target impedance. The target voltage gain is the system voltage gain of the active noise matching transformer without the feedback module, and the target voltage gain is calculated under the condition that the equivalent output resistance of a loop where the primary coil, the secondary coil, and the magnetohydrodynamic angular vibration sensor are located is equal to an 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 of the first active amplifier and the power spectral density of the equivalent input current of the first active amplifier.

2. The active noise matching transformer according to claim 1, wherein The feedback module includes a first feedback resistor and a second feedback resistor; Wherein, a first end of the first feedback resistor is electrically connected to a second end of the primary coil and a 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 an output end of the first active amplifier.

3. The active noise matching transformer according to claim 2, wherein, The resistance value of the second feedback resistor is configured according to the turns ratio of the secondary coil to the primary coil, the resistance value of the source resistor, and the voltage gain coefficient of the first active amplifier, where the source resistor is the equivalent resistance of a sensor sensitive element included in the magnetohydrodynamic angular vibration sensor.

4. The active noise matching transformer according to claim 3, wherein The resistance value of the first feedback resistor is configured according to the turns ratio of the secondary coil to the primary coil and the resistance value of the source resistor.

5. The active noise matching transformer according to claim 4, characterized in that, The first target transfer function of the system voltage gain of the active noise matching transformer is obtained according to the following operations: After adding the resistance values of the first feedback resistor and the second feedback resistor, multiplying them successively by the inductance value 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 values of the first feedback resistor and the second feedback resistor to obtain a second term; Multiplying the resistance value of the first feedback resistor and the resistance value of the source resistor to obtain a third term; Multiplying the resistance value of the second feedback resistor and the resistance value of the source resistor to obtain a fourth term; Add 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 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 multiply the sum by the inductance value of the primary coil to obtain the fifth term; Obtain the first target transfer function according to the first term, the second term, the third term, the fourth term, and the fifth term; 6. The active noise matching transformer according to claim 1, wherein 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; The two input ends of the second active amplifier are electrically connected to the two ends of the secondary coil respectively; 7. The active noise matching transformer according to claim 6, wherein The resistance value of the second feedback resistor is determined according to the turns ratio of the secondary coil to the primary coil, the resistance value of the source resistor, and the voltage gain coefficient of the second active amplifier, where the source resistor is the equivalent resistance of the sensor sensitive element included in the magnetohydrodynamic angular vibration sensor; 8. The active noise matching transformer according to claim 7, characterized in that, The resistance value of the first feedback resistor is configured according to the turns ratio of the secondary coil to the primary coil and the resistance value of the source resistor; 9. The active noise matching transformer according to claim 8, wherein The second target transfer function of the system voltage gain of the active noise matching transformer is obtained according to the following operations: Add the resistance value of the first feedback resistor and the resistance value of the second feedback resistor, and then multiply the sum by the inductance value 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 the first term; Multiply the resistance value of the first feedback resistor and the resistance value of the second feedback resistor to obtain the second term; Multiply the resistance value of the first feedback resistor and the resistance value of the source resistor to obtain the third term; Multiply the resistance value of the second feedback resistor and the resistance value of the source resistor to obtain the fourth term; Add 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 multiply the sum by the inductance value of the primary coil to obtain the fifth term; Obtain the second target transfer function according to the first term, the second term, the third term, the fourth term, and the fifth term; 10. The active noise matching transformer according to claim 4 or 8, 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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