NMR gyroscope fast closed loop control of excitation magnetic field

Abstract

The application discloses a kind of quick closed-loop control methods of nuclear magnetic resonance gyro excitation magnetic field, using a set of wave trap filter in cascade to filter mixed signal frequency division, obtain with 129 Xe and 131 Larmor precession frequency of Xe Single-phase sinusoidal signal of base frequency, through SOGI second-order generalized integrator to generate orthogonal signal, through Park transformation to obtain phase error, finally through the loop filter in PLL and voltage controller feedback excitation magnetic field signal, complete closed-loop control.The quick closed-loop control method of nuclear magnetic resonance gyro excitation magnetic field proposed in the application has high-precision frequency separation ability and fast phase tracking ability, and has the effect of improving the stability of the overall system.

Description

Technical Field

[0001] This invention belongs to the technical field of complex system detection and control, and mainly relates to a fast closed-loop control method for the excitation magnetic field of a nuclear magnetic resonance gyroscope. Background Technology

[0002] Gyroscopes, as crucial precision instruments in inertial navigation, are used to measure the angular velocity or angular displacement of a vehicle. Gyroscope technology has a history of over 160 years and can be categorized by working principle into rotor gyroscopes, optical gyroscopes, vibrating gyroscopes, and atomic gyroscopes. Newer atomic gyroscopes include spin-free exchange relaxation gyroscopes (SERFG), atomic interferometer gyroscopes (AIG), and nuclear magnetic resonance gyroscopes (NMRG). These atomic gyroscopes offer strong anti-interference capabilities, small size, and high precision.

[0003] Among them, the nuclear magnetic resonance gyroscope is a novel quantum gyroscope with high precision and small size. Its main core component is an atomic gas cell filled with alkali metal atoms and inert gas atoms. Nuclear magnetic resonance refers to the addition of a static magnetic field and an excitation magnetic field perpendicular to the static magnetic field in the direction of the gas cell, causing the inert gas atoms to generate a three-dimensional macroscopic magnetic moment and induce Larmor precession in the static magnetic field. When the frequency of the excitation magnetic field matches the Larmor precession frequency of the atoms, nuclear magnetic resonance will be formed. When the carrier has a certain rotational speed, the precession frequency of the macroscopic magnetic moment will be superimposed with the carrier's rotational speed. This superimposed rotational speed is observed by an atomic magnetometer formed of alkali metals. The frequency of the excitation magnetic field needs to be adjusted in real time according to the observed frequency of the macroscopic magnetic moment to form a magnetic field closed loop to achieve nuclear magnetic resonance stability and improve the measurement range of the gyroscope's rotational speed.

[0004] In practical systems, inert gases are generally used. 129 Xe / 131 The rotational speed of a nuclear magnetic resonance gyroscope is measured using a dual-working-substrate gas chamber composed of Xe gas. This method allows for differential measurement of the carrier's rotational angular velocity, effectively reducing measurement errors caused by static magnetic field interference. Theoretically, this method can neglect the influence of the static magnetic field on the rotational speed, thus showing greater promise. However, it also implies that the system requires a more complex closed-loop control method for the excitation magnetic field. The main challenges lie in:

[0005] (i) It is necessary to separate the observations from those taken in the same air chamber. 129 Xe / 131 Two frequency signals generated by Xe excitation;

[0006] (ii) The excitation closed loop needs a certain degree of adaptive capability to cope with the rapidly changing carrier rotation speed and frequency.

[0007] While the closed-loop control method for separating the excitation magnetic field based on traditional integral cascade filters has some effectiveness in handling the separation of mixed speed signals, it also has some potential drawbacks: 1. High complexity and cost: Implementing this closed-loop control method requires the design and implementation of complex circuits and algorithms, which increases the cost and complexity of the system, especially under high-precision requirements. 2. High requirements for signal processing: This method relies on filtering and separating mixed signals, requiring high-level algorithms and techniques for signal processing, including filter design and parameter tuning. 3. Stability and reliability challenges: The stability and reliability of the closed-loop control system are crucial for high-precision instruments such as NMR gyroscopes. Due to the complex signal processing and control loops involved, system stability and robustness may face challenges. 4. Sensitivity to environmental changes: The system performance may be affected by environmental factors such as temperature changes and electromagnetic interference, which may lead to a decrease in the performance of the closed-loop control or its failure.

[0008] Therefore, obtaining signals of the corresponding frequency under the operation of a complex duplex medium gas chamber system, responding quickly and accurately to rapidly changing rotational speeds, and providing stable closed-loop feedback to the excitation magnetic field are the key points and challenges of rotational speed measurement and closed-loop control in nuclear magnetic resonance gyroscopes. Summary of the Invention

[0009] This invention addresses the problem that traditional closed-loop control methods for filtering and separating the excitation magnetic field using integral-series filters heavily rely on high-performance digital signal processing algorithms and are easily affected by environmental interference, leading to inadequate sensitivity of the feedback excitation magnetic field signal to the sensitive atomic gas chamber and potential resonance failure. It provides a fast closed-loop control method for the excitation magnetic field of a nuclear magnetic resonance gyroscope, using a cascaded set of notch filters to filter and divide the mixed signal, obtaining a signal with... 129 Xe and 131 The single-phase sinusoidal signal with the Larmor precession frequency of Xe as the fundamental frequency is used to generate orthogonal signals through a second-order generalized integrator (SOGI). The phase error is obtained through Park transform, and finally, the excitation magnetic field signal is fed back through a loop filter and voltage controller in the PLL, completing closed-loop control. The fast closed-loop control method for the excitation magnetic field of the nuclear magnetic resonance gyroscope proposed in this invention has high-precision frequency separation capability and fast phase tracking capability, which improves the overall system stability.

[0010] To achieve the above objectives, the technical solution adopted by this invention is: a fast closed-loop control method for the excitation magnetic field of a nuclear magnetic resonance gyroscope, which uses a cascaded set of notch filters to filter and divide the mixed signal to obtain a result. 129 Xe and 131The single-phase sinusoidal signal with the Larmor precession frequency of Xe as the fundamental frequency is generated into an orthogonal signal by the SOGI second-order generalized integrator. The phase error is obtained by the Park transform, and finally the excitation magnetic field signal is fed back through the loop filter and voltage controller in the PLL to complete the closed-loop control.

[0011] As an improvement of the present invention, a fast closed-loop control method for the excitation magnetic field of a nuclear magnetic resonance gyroscope includes the following steps:

[0012] S1: Determine the current gyroscope based on... 129 Xe and 131 The operation is carried out in a chamber composed of two inert isotope gases, Xe, through... 87 The Rb magnetometer is sensitive to the macroscopic magnetic moment component to detect the rotational speed signal, wherein the steady-state magnetic moment detection signal is Ψ. dual (t);

[0013] S2: The detection result of step S1, using a notch filter to filter out the contents. 129 Xe and 131 Xe rotation speed signal Ψ dual (t) performs frequency separation to obtain the following values ​​respectively. 129 Xe and 131 Xe is a single-phase sinusoidal signal with the fundamental frequency;

[0014] S3: Use the SOGI second-order generalized integrator to generate mutually orthogonal signals from the single-phase sinusoidal signal obtained in step S2;

[0015] S4: Perform direct phase detection based on the quadrature signal obtained in step S3, and use a phase-locked loop to detect the rotational frequency ω. r To identify the error, the finite difference method is used to eliminate measurement error in the solution.

[0016] S5: The rotational speed frequency and the Larmor precession frequency of the inert gas in step S4 are used as the complete excitation magnetic field closed-loop feedback output to adjust the motion state of the gyroscope and realize closed-loop control.

[0017] As an improvement of the present invention, the steady-state magnetic moment detection signal Ψ in step S1 dual (t) Specifically:

[0018]

[0019] In the formula, Ψ 129 and Ψ 131 They are respectively 129 Xe and 131 Xe is the steady-state detection amplitude of the transverse magnetic moment, B0 is the static magnetic field along the Z-axis, and γ is the amplitude of the transverse magnetic moment. 129 and γ 131 They are respectively 129 Xe and 131The gyrometry of Xe and They are respectively 129 Xe and 131 The phase of the Xe steady-state magnetic moment detection signal, where t is the detection time.

[0020] As another improvement of the present invention, in the frequency separation process of step S2, the parameters of the notch filter are designed, and the equivalent transfer function model of the notch filter is:

[0021]

[0022] Where, ω th The notch center frequency selected for the notch filter, and ξ1 and ξ2 are the notch coefficients, are as follows:

[0023]

[0024] ξ2=Dξ1

[0025]

[0026] Where D is the notch depth at the center frequency of the notch, and B w The width of the notch at the center frequency.

[0027] As another improvement of the present invention, the notch filter used in step S2 is composed of three notch filters cascaded together, with a notch center frequency interval of 2π×0.5rad / s, a notch depth of 0.00001 (-100dB) for each filter, and a notch width of 2π×20rad / s for each filter.

[0028] As another improvement of the present invention, the SOGI second-order generalized integrator used in step S3 has the following transfer function:

[0029]

[0030] Where, k sg ω is the gain coefficient of SOGI. n H is the natural frequency of SOGI. α (s) and H β (s) are the transfer function expressions for the second-order bandpass filter and the second-order lowpass filter, respectively.

[0031] As another improvement of the present invention, the Park transform method is used to perform speed phase detection on the orthogonal signals in step S4. The transformation for the two orthogonal signals is as follows:

[0032]

[0033] When the phase-locked loop locks the phase, the difference between the original phase and the estimated phase of the signal is small, which is considered to be Ψ. 129d For amplitude estimation of the input signal, Ψ 129q The phase detection process is completed in proportion to the feedback error of the phase.

[0034] As another improvement of the present invention, the observation frequencies of the 129Xe and 131Xe macroscopic magnetic moments under static magnetic field interference are taken into account.

[0035] ω obs129 =γ 129 (B0+δB0)+ω r

[0036] ω obs131 =γ 131 (B0+δB0)+ω r

[0037] The rotational speed obtained by solving the above formula eliminates the interference of static magnetic field:

[0038]

[0039] As a further improvement of the present invention, the excitation feedback magnetic field obtained in step S5 will be provided to the dual working chambers as an excitation magnetic field signal, and the frequency of the excitation magnetic field signal will be consistent with the observed rotational speed.

[0040]

[0041] in This is the X-axis excitation signal. The excitation magnetic field signal along the Y-axis. and Based on 129 Xe and 131 Xe observes the excitation magnetic field signal generated by the rotational speed, B0 is the static magnetic field along the Z-axis, and γ 129 and γ 131 They are respectively 129 Xe and 131 The gyrometry of Xe and They are respectively 129 Xe and 131 Xe is the phase of the observed rotational speed signal, and t is the detection time.

[0042] Compared with existing technologies, this invention offers the following advantages: The fast closed-loop control method for the excitation magnetic field of a dual-working-substrate nuclear magnetic resonance gyroscope proposed in this invention achieves rapid and accurate frequency separation. The orthogonal signal generator phase-locked loop can quickly lock the frequency-separated signals into phases, resulting in excellent real-time performance. Under this closed-loop method, the gyroscope exhibits better dynamic response characteristics and system stability, and its common-mode interference immunity is improved. Testing shows a 7Hz bandwidth at the resonant frequencies of 85Hz and 25Hz. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of the structure of the method of the present invention;

[0044] Figure 2 This is a diagram showing the internal structure of a phase-locked loop (QSG-PLL) based on a quadrature signal generator, as shown in Embodiment 2 of the present invention.

[0045] Figure 3 This is a graph showing the test results of the phase-locked loop bandwidth based on the quadrature signal generator in the test examples of this invention. Detailed Implementation

[0046] The present invention will be further illustrated below with reference to the accompanying drawings and specific embodiments. It should be understood that the following specific embodiments are for illustrative purposes only and are not intended to limit the scope of the present invention.

[0047] Example 1

[0048] A fast closed-loop control method for the excitation magnetic field of a nuclear magnetic resonance gyroscope includes the following steps:

[0049] Step S1: Based on the basic components of the gyroscope's air chamber, determine that the current gyroscope should be based on... 129 Xe and 131 It operates in a chamber composed of two inert isotope gases, Xe, while simultaneously... 87 The Rb magnetometer is sensitive to the macroscopic magnetic moment component to detect the rotational speed signal. Therefore, it is necessary to analyze the output signal Ψ. dual (t) is used for detection;

[0050] The macroscopic magnetic moment component generated in the current dual-workpiece NMR gyroscope is measured in the Y direction, and the measured magnetic moment signal is: 129 Xe and 131 The superposition of the magnetic moment signals of Xe and Xe, using Ψ dual (t) is used to achieve closed-loop control of the excitation magnetic field for the two isotopes. The steady-state magnetic moment detection signal can then be written as: Among them Ψ 129 and Ψ 131 They are respectively 129 Xe and 131The steady-state detection amplitude of the Xe transverse magnetic moment is constant; the two dynamic phases are represented as: as well as The dynamic phase includes the static magnetic field disturbance δB0 and the carrier rotational angular velocity ω. r Information.

[0051] Step S2: Based on the current detection state in step S1, design a notch filter to filter the included... 129 Xe and 131 Xe rotation speed signal Ψ dual (t) performs frequency separation to obtain the following values ​​respectively. 129 Xe and 131 Xe is a single-phase sinusoidal signal with the fundamental frequency;

[0052] Consider using a notch filter bank for Ψ dual In (t), the two signals are first separated by frequency, for example, by filtering out The component, since the notch filter bank has very little effect on signals far from the notch frequency, the remaining signal is: In the process of frequency separation, appropriate parameters need to be selected for the design of the notch filter. The equivalent transfer function model of the notch filter is as follows:

[0053]

[0054] Where ω th The notch center frequency is selected for the notch filter, and ξ1 and ξ2 are the notch coefficients. D is designed as the notch depth at the notch center frequency, and B... w The notch width at the center frequency of the notch is given by the formula for calculating the notch coefficient:

[0055]

[0056] In application, multiple notch filters with similar center frequencies are cascaded to form a notch filter bank, thereby obtaining a wider and deeper stopband. The notch center frequency of the notch filter bank varies with the output of the phase-locked loop. and Real-time adjustments ensure the reliability of frequency separation, taking into account... 129 Xe and 131 The Larmor precession frequencies of Xe at a magnetic field strength of 7.143T are 25Hz and 85Hz, so the center frequencies of the notch filters are mainly selected at 25Hz and 85Hz.

[0057] The notch filter array used in the frequency division consists of three cascaded notch filters with a center frequency interval of 2π × 0.5 rad / s, a notch depth of 0.00001 (-100 dB), and a notch width of 2π × 20 rad / s. This results in a stopband width of approximately 1.5 Hz at -80 dB, meaning that even without frequency feedback, as long as... 129 Xe and 131 Frequency separation can be effectively performed when the Xe resonant frequency varies within ±0.75Hz.

[0058] Step S3: Use the SOGI second-order generalized integrator to generate mutually orthogonal signals from the single-phase sinusoidal signal obtained in step S2;

[0059] An orthogonal signal generator is used to generate two mutually orthogonal signals from a single-phase signal. A second-order generalized integrator, SOGI, is used, and its transfer function is:

[0060]

[0061] Where k sg ω is the gain coefficient of SOGI. n H is the natural frequency of SOGI. α (s) and H β (s) are second-order bandpass and second-order lowpass filters, which can effectively suppress high-frequency noise in the signal. The steady-state output signals are orthogonal and have equal amplitudes only when the input signal frequency matches the natural frequency of SOGI. Simultaneously, the input signal frequency is affected by the carrier's rotational angular velocity and static magnetic field interference, therefore, the natural frequency of SOGI needs to be adjusted according to the phase-locked loop output, i.e. (by 129 (Example of Xe splitting), thus enabling SOGI to have adaptive characteristics.

[0062] At the same time, it is necessary to consider how to determine the gain coefficient of SOGI, and to take... Among them U and Let u be the amplitude and phase of the input signal, respectively, both constants. When u is input into SOGI, k must satisfy... sg <2, at this point the output signal can be obtained:

[0063]

[0064] in It's about U. k sg The function. Therefore, the output signal needs to suppress the oscillating convergence term, and the convergence rate of this term is affected by the coefficient k. sg The influence of k is taken comprehensively. sg =1.414.

[0065] After a single-phase signal passes through SOGI, SOGI can then pass through the input signal Ψ. 129 (t) Generates a pair of orthogonal signals. The amplitude and frequency of the output signals are consistent with the input signals, but the phase of one signal is consistent with the input signal, while the other lags behind the original phase by 90° (within t). 129 Example of Xe splitting): and

[0066] Step S4: The rotational speed phase detection of the orthogonal signals is performed using the Park transform method. The transform for two orthogonal signals is as follows:

[0067]

[0068] When the phase-locked loop locks the phase, the difference between the original phase and the estimated phase of the signal is small, and after approximation, Ψ can be considered... 129d This refers to the amplitude estimation of the input signal, Ψ. 129q That is, it is proportional to the feedback error of the phase, thus completing the phase detection process.

[0069] Direct phase detection is performed using the obtained orthogonal signals, and the rotational speed frequency ω is monitored via a phase-locked loop. r The system is identified and the finite difference method is used to solve it, eliminating the measurement error caused by static magnetic field fluctuations.

[0070] The rotational speed of the carrier needs to be calculated. The finite difference method is used to eliminate measurement errors caused by static magnetic field fluctuations, considering the carrier's rotation under static magnetic field conditions.

[0071] ω obs129 =γ 129 (B0+δB0)+ω r

[0072] ω obs131 =γ 131 (B0+δB0)+ω r

[0073] Taking into account the observation frequencies of the macroscopic magnetic moments 129Xe and 131Xe for static magnetic field interference, the rotational speed obtained by solving the above formula eliminates static magnetic field interference:

[0074]

[0075] Step S5: Combining the rotational speed frequency from step S4 and the Larmor precession frequency of the inert gas as a complete closed-loop feedback output of the excitation magnetic field, the motion state of the gyroscope is adjusted accordingly.

[0076] Simultaneously, the rotational speed frequency and the Larmor precession frequency of the inert gas are used as the complete closed-loop feedback output of the excitation magnetic field. That is, the excitation feedback magnetic field obtained at this time will be provided to the dual working chambers as the excitation magnetic field signal, and the frequency of the excitation magnetic field signal will be consistent with the observed rotational speed. in

[0077] Example 2

[0078] A fast closed-loop control method for the excitation magnetic field of a nuclear magnetic resonance gyroscope, such as... Figure 1 As shown, a static magnetic field B0 is applied to the gas cell of the nuclear magnetic resonance gyroscope along the Z-axis, and an excitation magnetic field B1cos(ω) is applied along the X-axis. a Furthermore, pump light is applied along the Z-axis to polarize alkali metal atoms, causing spin polarization between them and inert gas atoms. Then, a detection aurora is applied along the X-axis to sensitize the rotating macroscopic magnetic moment, resulting in Ψ with a mixed frequency signal. dual (t).

[0079] Next, a notch filter bank is used, with the frequencies calculated by the two phase-locked loops as the notch center frequencies, to obtain fundamental frequency signals containing 129Xe and 131Xe Larmor progression frequencies, for example, filtering out... The component, since the notch filter bank has very little effect on signals far from the notch frequency, the remaining signal is: Secondly, the single-phase signal is dephased using QSG-PLL to obtain the carrier rotation frequency. Finally, the carrier rotation frequency is fed back to the excitation magnetic field signal generator to complete the magnetic field closed-loop feedback loop. At the same time, the frequencies calculated by the two QSG-PLLs are calculated to obtain the actual carrier frequency that is not affected by static magnetic field fluctuations.

[0080] like Figure 2 As shown, the quadrature signal generator, combined with Park's variation, forms a phase detector. The loop filter still consists of a PI controller, and the integrator corresponds to a voltage-controlled oscillator. Ideally, the quadrature signal generator can determine the phase of the input signal Ψ. 129 (t) Immediately generate a pair of orthogonal signals, and then perform a pair of orthogonal signals Ψ 129α and Ψ 129β Perform the Park transform to obtain the dq-axis signal Ψ 129d and Ψ 129q When the phase-locked loop is in a quasi-locked state and The difference is small, and after approximation, Ψ can be seen. 129d This refers to the amplitude estimation of the input signal, Ψ. 129q The feedback error is proportional to the phase, thus completing the phase detection.

[0081] Test case

[0082] Three notch filters are cascaded to form a notch filter group, with a notch frequency interval of 2×π×0.5 rad / s, a notch depth of 0.00001, and a notch width of 2×π×20 rad / s for each filter. The phase-locked loop (PLL) PI parameters are adjusted to... 129 The closed-loop bandwidth of the Xe excitation magnetic field is approximately 10 Hz. 131 The Xe closed-loop bandwidth is approximately 4 Hz. In traditional frequency-based phase-locked loop (PLL) closed-loop schemes, the closed-loop bandwidth of the excitation magnetic field is determined by the LPF cutoff frequency, which is typically set at 3.5 Hz.

[0083] During simulation, the system is first allowed to reach steady state. After 150 seconds, a step angular velocity signal of 5° / s is introduced. The output is used to measure the gyroscope performance under the two schemes. The bandwidth of the traditional scheme is approximately 3.5Hz; the bandwidth of the scheme presented in this paper is approximately 7Hz, falling between the set 10Hz and 4Hz. The bandwidth of both schemes meets expectations. Figure 3 As shown, the traditional scheme has a resonant peak of 10.8dB at 2.5Hz, while the scheme in this paper has a resonant peak of only 1.6dB at 2Hz. The gyroscope system constructed by the traditional scheme has poor stability and the system's step response will have a larger overshoot.

[0084] In summary, this invention discloses a fast closed-loop control method for the excitation magnetic field of a nuclear magnetic resonance gyroscope, which separates the mixed signal containing... 129 Xe and 131 Xe is a single-phase sinusoidal signal with the fundamental frequency. It generates an orthogonal signal through a second-order generalized integrator of SOG I, then obtains the phase error through Park transform, and finally feeds back the excitation magnetic field signal through the loop filter and voltage controller in the PLL to complete the complete closed-loop control. It has a fast and accurate frequency separation effect and good real-time performance.

[0085] It should be noted that the above content merely illustrates the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. For those skilled in the art, various improvements and modifications can be made without departing from the principle of the present invention, and all such improvements and modifications fall within the scope of protection of the claims of the present invention.

Claims

1. A fast closed-loop control method for the excitation magnetic field of a nuclear magnetic resonance gyroscope, characterized in that: A cascaded set of notch filters is used to filter and divide the mixed signal to obtain the desired result. 129 Xe and 131 The single-phase sinusoidal signal with the Larmor precession frequency of Xe as the fundamental frequency is used to generate orthogonal signals through a second-order generalized integrator (SOGI). The phase error is obtained through Park transform, and finally, the excitation magnetic field signal is fed back through the loop filter and voltage controller in the PLL to complete the closed-loop control. The process includes the following steps: S1: Determine the current gyroscope based on... 129 Xe and 131 It operates in a chamber composed of two inert isotope gases, Xe, and others, through... 87 The Rb magnetometer is sensitive to the macroscopic magnetic moment component to detect the rotational speed signal, wherein the steady-state magnetic moment detection signal is: ; S2: The detection result of step S1, using a notch filter to filter out the contents. 129 Xe and 131 Xe rotation speed signal Perform frequency separation to obtain the following: 129 Xe and 131 Xe is a single-phase sinusoidal signal with the fundamental frequency; during frequency separation, the parameters of the notch filter are designed, and the equivalent transfer function model of the notch filter is: in, The notch center frequency selected for the notch filter. and The notch filter coefficient is as follows: Where D is the notch depth at the center frequency of the notch. The width of the notch at the center frequency; S3: Use the SOGI second-order generalized integrator to generate mutually orthogonal signals from the single-phase sinusoidal signal obtained in step S2; S4: Perform direct phase detection based on the quadrature signal obtained in step S3, and use a phase-locked loop to control the rotational speed and frequency. To identify the error, the finite difference method is used to eliminate measurement error in the solution. S5: The rotational speed frequency and the Larmor precession frequency of the inert gas in step S4 are used as the complete excitation magnetic field closed-loop feedback output to adjust the motion state of the gyroscope and realize closed-loop control.

2. The fast closed-loop control method for the excitation magnetic field of a nuclear magnetic resonance gyroscope as described in claim 1, characterized in that: The steady-state magnetic moment detection signal in step S1 Specifically: In the formula, and They are respectively 129 Xe and 131 Xe transverse magnetic moment steady-state detection amplitude The static magnetic field along the Z-axis. and They are respectively 129 Xe and 131 The gyrometry of Xe and They are respectively 129 Xe and 131 Phase of the Xe steady-state magnetic moment detection signal For the detection time.

3. The fast closed-loop control method for the excitation magnetic field of a nuclear magnetic resonance gyroscope as described in claim 2, characterized in that: The notch filter used in step S2 is composed of three cascaded notch filters with a notch center frequency interval of 2π×0.5rad / s, a notch depth of 0.00001 (-100dB) for each filter, and a notch width of 2π×20rad / s for each filter.

4. The fast closed-loop control method for the excitation magnetic field of a nuclear magnetic resonance gyroscope as described in claim 3, characterized in that: The SOGI second-order generalized integrator used in step S3 has the following transfer function: in, This is the gain coefficient of SOGI. The natural frequency of SOGI. and These are the transfer function expressions for a second-order bandpass filter and a second-order lowpass filter, respectively.

5. The fast closed-loop control method for the excitation magnetic field of a nuclear magnetic resonance gyroscope as described in claim 4, characterized in that: In step S4, the Park transform method is used to perform speed phase detection on the orthogonal signals. The transformation for two orthogonal signals is as follows: When a phase-locked loop locks the phase, the difference between the original phase and the estimated phase of the signal is small, and it is considered that... For amplitude estimation of the input signal, The phase detection process is completed in proportion to the feedback error of the phase.

6. The fast closed-loop control method for the excitation magnetic field of a nuclear magnetic resonance gyroscope as described in claim 5, characterized in that: In step S4, the observation frequencies of the 129Xe and 131Xe macroscopic magnetic moments considering static magnetic field interference are taken into account. The rotational speed obtained by solving the above formula eliminates the interference of static magnetic field: 。 7. The fast closed-loop control method for the excitation magnetic field of a nuclear magnetic resonance gyroscope as described in claim 6, characterized in that: The excitation feedback magnetic field obtained in step S5 will be provided to the dual working chambers as an excitation magnetic field signal, and the frequency of the excitation magnetic field signal will be consistent with the observed rotational speed. in This is the X-axis excitation signal. The excitation magnetic field signal along the Y-axis. and Based on 129 Xe and 131 Xe observes the excitation magnetic field signal generated by the rotational speed. The static magnetic field along the Z-axis. and They are respectively 129 Xe and 131 The gyrometry of Xe and They are respectively 129 Xe and 131 Xe observes the phase of the rotational speed signal. For the detection time.

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