Frequency compensation type quartz accelerometer excitation drive circuit

Abstract

The invention relates to a frequency compensation type quartz accelerometer excitation drive circuit, which comprises a voltage conversion module, an excitation drive module and a frequency compensation module, and is characterized in that the voltage conversion module is connected with the excitation drive module and the frequency compensation module, and the front stage of the excitation drive module is connected with the frequency compensation module; the excitation driving module front stage is connected with the excitation driving module rear stage; the voltage conversion module is used for converting external power supply voltage into low voltage and supplying power to the excitation driving module and the frequency compensation module; the excitation driving module is connected with the quartz resonant beam to jointly form a closed loop and realize self-excitation oscillation; and the frequency compensation module is used for improving the output temperature characteristic of the quartz vibrating beam accelerometer. The driving device is high in driving capacity, high in output precision and good in stability, can directly reduce the influence of temperature on the quartz vibrating beam accelerometer, has the advantages of being simple in structure, small in number of components and easy to miniaturize, can be applied to vibrating accelerometers of similar vibrating beam structural forms, and has universality.

Description

Technical Field

[0001] The invention belongs to the technical field of inertial element driving, in particular to an excitation driving circuit of a frequency compensation type quartz accelerometer. Background Art

[0002] Inertial elements such as gyroscopes and accelerometers are important components of the inertial navigation system. The accelerometer is mainly used to sense the magnitude of linear acceleration. The inertial navigation system determines the position of the carrier by integrating the linear acceleration over time, thereby obtaining the motion state of the carrier and achieving autonomous navigation.

[0003] The quartz vibration beam accelerometer is a high-precision accelerometer based on the piezoelectric effect and force-frequency characteristics of quartz crystals. According to the force-frequency characteristics, the inertial force formed by the input acceleration changes the equivalent stiffness of the quartz resonance beam to change its inherent resonant frequency; under the excitation of the excitation drive circuit, the quartz resonance beam forms bending vibration based on the inverse piezoelectric effect, thereby generating a frequency output, and the acceleration information can be sensed through frequency measurement. The quartz vibration beam accelerometer has few parts, small size, simple structure, large range, high scale factor, wide dynamic range, high stability and high precision, and low power consumption. The direct frequency output can reduce the accuracy loss caused by analog-to-digital conversion, and has broad application prospects in the field of inertial navigation.

[0004] As an important component of the quartz beam accelerometer, the excitation drive circuit is the key to achieving the quartz resonant beam oscillation and frequency output. The excitation drive circuit and the quartz resonant beam together form a closed loop, using self-excited oscillation to form frequency output, and forming high gain through linear amplification to achieve the quartz resonant beam oscillation, and meet the amplitude balance and phase balance conditions for the continuous oscillation of the quartz resonant beam.

[0005] The quartz resonant beam can be driven by a series oscillation circuit or a parallel oscillation circuit. Usually, the quartz resonant beam has the characteristics of high impedance (up to MΩ level), which is equivalent to a high-value inductor in the parallel oscillation circuit, with a small driving current and difficult to start oscillation; and the parallel oscillation frequency is related to the static capacitance and external capacitance of the quartz resonant beam, and the self-stabilizing frequency capability is poor. In the series oscillation circuit, the quartz resonant beam is purely resistive, but in order to meet the needs of a larger range and higher sensitivity, the designed and processed double-ended fixed tuning fork quartz resonant beam (DETF) may have tens of MΩ in equivalent impedance, and the driving capability needs to be further improved; in addition, due to the choice of cutting type when processing quartz crystals, the quartz resonant beam will have a non-zero temperature coefficient, and the process level is not perfect when the dual resonant beam is symmetrically assembled, as well as the differences between the properties of the quartz resonant beam and the adhesive and pendulum mass materials, the output of the quartz resonant beam accelerometer will drift with temperature changes. Summary of the invention

[0006] The purpose of the present invention is to overcome the shortcomings of the prior art and propose a frequency compensated quartz accelerometer excitation drive circuit, which utilizes multi-stage cascade amplification of CMOS inverters, introduces gain adjustment and filtering networks to suppress noise interference, reduces the influence of temperature changes through frequency compensation, realizes excitation drive of ultra-high impedance quartz resonant beam, improves the output frequency accuracy and stability of the quartz resonant beam accelerometer, and improves its output temperature characteristics.

[0007] The present invention solves the technical problem by adopting the following technical solutions:

[0008] A frequency compensation type quartz accelerometer excitation drive circuit comprises a voltage conversion module, an excitation drive module and a frequency compensation module, wherein the voltage conversion module is respectively connected to the excitation drive module and the frequency compensation module, the front stage of the excitation drive module is connected to the frequency compensation module, and the front stage of the excitation drive module is connected to the rear stage of the excitation drive module; the voltage conversion module is used for converting an external power supply voltage to a low voltage and supplying power to the excitation drive module and the frequency compensation module; the excitation drive module is connected to a quartz resonance beam to jointly form a closed loop and realize self-excited oscillation; the frequency compensation module is used for improving the output temperature characteristics of the quartz vibration beam accelerometer.

[0009] Moreover, the input end of the voltage conversion module is directly connected to the external power supply, and the output end is used to provide the converted power to the excitation drive module and the frequency compensation module respectively, and the high power supply voltage is converted into a low power supply compatible with the CMOS level through the principle of linear voltage regulation.

[0010] Moreover, the excitation drive module includes an excitation drive module front stage and an excitation drive module back stage, wherein the excitation drive module front stage includes a linear amplification link, a phase shift amplification link, a gain adjustment and filtering network and a linear amplification and amplitude stabilization link, the linear amplification link, the phase shift amplification link, the gain adjustment and filtering network and the linear amplification and amplitude stabilization link are connected in sequence, the output end of the linear amplification and amplitude stabilization link is respectively connected to the frequency compensation module and the quartz resonant beam, the input end of the linear amplification link is connected to the quartz resonant beam, and the output end of the linear amplification link is connected to the phase shift amplification link; the linear amplification link, the phase shift amplification link, the gain adjustment and filtering network and the linear amplification and amplitude stabilization link and the quartz resonant beam together constitute a closed-loop positive feedback loop, which is used for the oscillation of the quartz resonant beam and meets the amplitude balance and phase balance conditions of continuous oscillation.

[0011] Moreover, the latter stage of the excitation drive module includes an output shaping link and a drive enhancement link, wherein the input end of the output shaping link is connected to the frequency compensation module, the output end of the output shaping link is connected to the drive enhancement link, the drive enhancement link outputs the excitation drive circuit output signal, the output shaping link is used to perform waveform shaping on the signal whose frequency is independent of temperature to improve the signal waveform quality; the drive enhancement link enhances the signal's load capacity by means of parallel driving and ensures that the phase remains unchanged, thereby finally forming the excitation drive circuit output signal.

[0012] Moreover, the frequency compensation module includes a thermistor, a sine wave generating link, a frequency conversion link and a square wave conversion link, wherein the thermistor, the sine wave generating link, the frequency conversion link and the square wave conversion link are connected in sequence, the thermistor is used to realize the temperature measurement of the quartz vibration beam accelerometer head, and is connected to the sine wave generating link as a bridge resistor; the sine wave generating link generates a sine wave signal whose frequency changes linearly with temperature according to the working principle of the RC oscillation circuit; the frequency conversion link realizes the multiplication of the driving signal and the sine wave signal through a multiplier, and obtains a sine wave signal whose frequency is independent of temperature after filtering by a phase shifter and a notch filter; the square wave conversion link converts the sine wave signal whose frequency is independent of temperature into a square wave signal whose frequency is independent of temperature through a zero-crossing comparator and a limiting diode.

[0013] The advantages and positive effects of the present invention are:

[0014] 1. The present invention includes a voltage conversion module, an excitation drive module and a frequency compensation module. The voltage conversion module is connected to the excitation drive module and the frequency compensation module respectively. The front stage of the excitation drive module is connected to the frequency compensation module, and the front stage of the excitation drive module is connected to the rear stage of the excitation drive module. The voltage conversion module is used to convert the external power supply voltage to low voltage and supply power to the excitation drive module and the frequency compensation module. The excitation drive module is connected to the quartz resonant beam to form a closed loop and realize self-excited oscillation. The frequency compensation module is used to improve the output temperature characteristics of the quartz vibration beam accelerometer. The present invention has strong driving ability, high output accuracy, good stability, and can directly reduce the influence of temperature on the quartz vibration beam accelerometer. At the same time, it has the advantages of simple structure, small number of components, and easy miniaturization. It can be applied to vibration accelerometers with similar vibration beam structures and has universality. It has huge economic value and social benefits in the fields of high-precision inertial navigation, gravity measurement, missile guidance, etc.

[0015] 2. The present invention forms a closed-loop positive feedback self-excited oscillation circuit by connecting linear amplification, phase-shift amplification, gain adjustment and filtering network, linear amplification and amplitude stabilization links in series. The multi-stage cascade method provides extremely high gain, enhances the driving ability of the circuit, and can effectively realize the oscillation of the ultra-high impedance quartz resonant beam.

[0016] 3. The present invention introduces a gain adjustment and filtering network into the closed-loop positive feedback series self-excited oscillation circuit. The gain adjustment can be achieved by adjusting the feedback resistor and the input resistor value of the operational amplifier circuit. Compared with adjusting the parallel resistor value of the CMOS inverter to change the gain, the adjustment method is simpler and more convenient, and the influence of the easy deviation of the static operating point is reduced. The first-order filtering network is introduced to filter the noise frequency signal, avoid the quartz resonant beam working at the overtone frequency, and the output frequency signal has high accuracy and good stability.

[0017] 4. The present invention converts the temperature information obtained by measuring the thermistor into a frequency signal in a manner of generating a sine wave through an RC oscillation circuit; by reasonably designing the parameters of the RC oscillation circuit, the magnitude of the frequency signal changing with temperature is kept consistent with that of a quartz resonant beam; the sine wave frequency signal with temperature information is further fused with a driving frequency signal through a multiplier, the temperature change portion is offset through frequency conversion, and the temperature-independent sine wave signal is converted into a CMOS level square wave frequency signal that is more easily received and processed by a digital system through notch filtering and waveform conversion, thereby directly reducing the influence of temperature on the quartz resonant beam accelerometer through frequency compensation. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural block diagram of the frequency compensation type excitation drive circuit of the present invention;

[0019] Figure 2 2 is a schematic diagram of the front stage principle of the excitation drive module according to an embodiment of the present invention;

[0020] Figure 3 is a schematic diagram of the principle of a frequency compensation module according to an embodiment of the present invention;

[0021] Figure 4 2 is a schematic diagram of the rear stage principle of the excitation drive module according to an embodiment of the present invention;

[0022] Figure 5 It is the frequency temperature curve of the quartz resonant beam under double-end fixation in the present invention.

[0023] Description of labels:

[0024] 1-voltage conversion module, 2-excitation drive module, 3-frequency compensation module, 4-excitation drive module front stage, 5-excitation drive module back stage, 6-quartz resonant beam, 7-linear amplification link, 8-phase shift amplification link, 9-gain adjustment and filtering network, 10-linear amplification and amplitude stabilization link, 11-output shaping link, 12-drive enhancement link, 13-excitation drive module front stage input signal, 14-excitation drive module front stage output drive signal, 15-thermistor, 16-sine wave generation link, 17-frequency conversion link, 18-square wave conversion link, 19-sine wave signal whose frequency changes with temperature, 20-sine wave signal whose frequency is independent of temperature, 21-square wave signal whose frequency is independent of temperature, 22-excitation drive circuit output signal. DETAILED DESCRIPTION

[0025] The present invention is further described in detail below with reference to the accompanying drawings.

[0026] A frequency compensation type quartz accelerometer excitation drive circuit, such as Figure 1 As shown, it includes a voltage conversion module 1, an excitation drive module 2 and a frequency compensation module 3. The voltage conversion module 1 is connected to the excitation drive module 2 and the frequency compensation module 3 respectively. The excitation drive module includes an excitation drive module front stage 4 and an excitation drive module rear stage 5. The excitation drive module front stage 4 is connected to the frequency compensation module 3, and the excitation drive module front stage 4 is connected to the excitation drive module rear stage 5; the voltage conversion module 1 is used to convert the external power supply voltage to a low voltage and supply power to the excitation drive module 2 and the frequency compensation module 3; the excitation drive module 2 is connected to the quartz resonant beam 6 to form a closed loop and realize self-oscillation; the frequency compensation module 3 is used to improve the output temperature characteristics of the quartz resonant beam accelerometer.

[0027] The input end of the voltage conversion module 1 is directly connected to the external power supply, and the output end is used to provide the converted power to the excitation drive module 2 and the frequency compensation module 3 respectively. Through the principle of linear voltage regulation, the high power supply voltage is converted into a low power supply compatible with the CMOS level.

[0028] The front stage 4 of the excitation driving module includes a linear amplifier link 7, a phase-shift amplifier link 8, a gain adjustment and filtering network 9 and a linear amplifier and amplitude stabilization link 10. The linear amplifier link 7, the phase-shift amplifier link 8, the gain adjustment and filtering network 9 and the linear amplifier and amplitude stabilization link 10 are connected in sequence. The output end of the linear amplifier and amplitude stabilization link 10 is respectively connected to the frequency compensation module 3 and the quartz resonance beam 6. The output end of the linear amplifier and amplitude stabilization link 10 outputs the front stage output drive signal 14 of the excitation driving module to the quartz resonance beam 6. The input end of the linear amplifier link 7 is connected to the quartz resonance beam 6, and the output end of the linear amplifier link 7 is connected to the phase-shift amplifier link 8; the linear amplifier link 7, the phase-shift amplifier link 8, the gain adjustment and filtering network 9 and the linear amplifier and amplitude stabilization link 10 and the quartz resonance beam 6 together constitute a closed-loop positive feedback loop, which is used for the oscillation of the quartz resonance beam and meets the amplitude balance and phase balance conditions of continuous oscillation.

[0029] The back stage 5 of the excitation drive module includes an output shaping link 11 and a drive enhancement link 12, wherein the input end of the output shaping link 11 is connected to the frequency compensation module 3, and the output end of the output shaping link 11 is connected to the drive enhancement link 12. The drive enhancement link 12 outputs the excitation drive circuit output signal 22. The output shaping link 11 is used to perform waveform shaping on the inverse square wave signal 21 whose frequency is independent of temperature to improve the signal waveform quality; the drive enhancement link 12 enhances the signal's load capacity by parallel driving and ensures that the phase remains unchanged, thereby finally forming the excitation drive circuit output signal 22.

[0030] The frequency compensation module 3 includes a thermistor 15, a sine wave generating link 16, a frequency conversion link 17 and a square wave conversion link 18, wherein the thermistor 15, the sine wave generating link 16, the frequency conversion link 17 and the square wave conversion link 18 are connected in sequence, the thermistor 15 has a linear temperature characteristic, is used to realize the temperature measurement of the quartz vibration beam accelerometer head, and is connected to the sine wave generating link 16 as a bridge resistor; the sine wave generating link 16 generates a sine wave signal 19 whose frequency changes with temperature according to the working principle of the RC oscillation circuit; the frequency conversion link 17 realizes the multiplication of the driving signal and the sine wave signal through a multiplier, and obtains a sine wave signal 20 whose frequency is independent of temperature after filtering by a phase shifter and a notch filter; the square wave conversion link 18 converts the sine wave signal 20 whose frequency is independent of temperature into a square wave signal 21 whose frequency is independent of temperature through a zero-crossing comparator and a limiting diode, and the amplitude of the square wave signal is limited to the CMOS level of +5V.

[0031] According to the above-mentioned frequency compensation type quartz accelerometer excitation drive circuit, an actual circuit module is constructed to conduct tests to illustrate the effect of the present invention.

[0032] Figure 2The figure is a schematic diagram of the front stage principle of the excitation drive module of the embodiment of the present invention. One electrode of the quartz resonant beam is connected to the input end of the CMOS inverter U1A and one end of the resistor R1, and the other electrode is connected to the resistor R6, one end of the resistor R7, and the positive electrode of the diode D1 and the negative electrode of the diode D2. The other end of the resistor R1 and the output end of the CMOS inverter U1A are connected to one end of the capacitor C1, and the resistor R1 and the CMOS inverter U1A together constitute a linear amplification link. The other end of the capacitor C2 is connected to the input end of the CMOS inverter U1B, the resistor R2 and one end of the capacitor C2, and the other end of the resistor R2 and the capacitor C2 together with the output end of the CMOS inverter U1B are connected to one end of the resistor R3, and the resistor R2 and the capacitor C2 are connected in parallel, and constitute a phase shift amplification link with the CMOS inverter U1B. The other end of the resistor R3 is connected to the negative input end of the operational amplifier U2A, the resistor R5 and one end of the capacitor C3. One end of the resistor R4 is connected to the positive input end of the operational amplifier U2A, and the other end is grounded. The output end of the operational amplifier U2A, the resistor R5 and the other end of the capacitor C3 are connected to the input end of the CMOS inverter U1C, and are also connected to the cathode of the diode D1, the anode of the diode D2 and one end of the resistor R6. The resistor R5 and the capacitor C3 are connected in parallel, and together with the operational amplifier U2A, they form a first-order filter. The resistor R3 and the resistor R5 are adjusted to achieve gain adjustment. The output end of the CMOS inverter U1C is connected to the other end of the resistor R7. The CMOS inverter U1C, the resistor R6, the resistor R7, the diode D1 and the diode D2 form a linear amplification and amplitude stabilization link.

[0033] Figure 3 The frequency compensation module of the embodiment of the present invention is a schematic diagram of the principle of the frequency compensation module. T1 One end of the resistor R8 is connected to one end of the high-value resistor R8, and the other end is connected to one end of the capacitor C4; the other end of the high-value resistor R8 is connected to the output end of the operational amplifier U2B and one end of the resistor R10, and the other end of the capacitor C4 is connected to the positive input end of the operational amplifier U2B, as well as the resistor R9 and one end of the capacitor C5; the other end of the resistor R9 is connected to the thermistor R T2 One end of the thermistor R T2 The other end of the resistor R10 is connected to the negative input terminal of the operational amplifier U2B and one end of the resistor R11, and the other end of the resistor R11 is grounded.

[0034] The thermistor R T1 and R T2 The same type of thermistor, satisfying R T1 =R T2 =R T , the resistance is:

[0035] R T =R0+K R T(1)

[0036] Where R0 is the basic resistance of the thermistor at 0°C; K R is the temperature coefficient of the thermistor; T is the temperature of the quartz resonant beam.

[0037] In addition, high-resistance resistor R8=R9=R, capacitor C4=C5=C, resistors R8, R9, R10, R11, R T1 and R T2 , capacitors C4 and C5, and operational amplifier U2B together form an RC oscillation circuit, i.e., a sine wave generating circuit. The generated sine wave frequency is:

[0038]

[0039] like Figure 5 As shown in the figure, the frequency-temperature characteristic of the quartz resonant beam under the double-end fixed constraint is approximately linear, and the output frequency f V for:

[0040] f V =f s +K V T = f s0 +K a ·a+K V ·T(3)

[0041] Among them, f s is the resonant frequency of the quartz resonant beam under the combined effect of input acceleration a and temperature T, f s0 K is the natural frequency of the quartz resonant beam at 0°C without acceleration input; a is the acceleration coefficient of the quartz resonant beam; a is the input acceleration; K V is the temperature conversion coefficient of the quartz resonant beam; T is the temperature of the quartz resonant beam.

[0042] The series resistors R8 and R9 are high-value resistors, so the nonlinear parts such as the quadratic term are ignored. According to the basic resistance value R0 and the temperature coefficient value K of the thermistor R , reasonably select and design the resistance values ​​of the series resistors R8 and R9 and the capacitance values ​​of the capacitors C4 and C5 in the RC oscillation circuit to ensure that the magnitude of the coefficient of change of the sine wave frequency with temperature is consistent with the temperature coefficient K of the quartz resonant beam. a Same size and direction:

[0043]

[0044] Therefore, the frequency of the generated sine wave is:

[0045]

[0046] The output of the operational amplifier U2B is connected to one of the input terminals of the multiplier U3, and the output of the linear amplification and amplitude stabilization link of the excitation drive module is connected to the other input terminal of the multiplier U3. The sine wave signal output by equation (5) is multiplied by the square wave signal of equation (3) to output the signal u o (t) is:

[0047]

[0048] Among them, E1 is the amplitude of the square wave signal output by the excitation drive module; E2 is the amplitude of the sine wave signal output by the sine wave generation link; is the phase deviation of the sine wave signal relative to the square wave signal.

[0049] The baseband signal part in formula (6) Expanded:

[0050]

[0051] The output end of the multiplier U3 is connected to capacitor C6 and one end of resistor R12, the other end of capacitor C6 is connected to resistor R14 and one end of capacitor C7, the other end of resistor R12 is connected to resistor R13 and one end of capacitor C8; the other end of resistor R14 is connected to the output end of operational amplifier U2C and one end of resistor R16, the other end of capacitor C7 is connected to the other end of resistor R13 and the positive input end of operational amplifier U2C, and the other end of capacitor C8 is grounded; the other end of resistor R16 is connected to one end of resistor R15 and the negative input end of operational amplifier U2C, and the other end of resistor R15 is grounded. Resistors R12, R13, R14, R15, R16 and capacitors C6, C7, C8 and operational amplifier U2C together form a notch filter, which filters out the high-frequency and low-frequency components in the multiplier output signal equations (6) and (7), and retains Part, the actual output sine wave signal frequency f s -f0 is independent of temperature.

[0052] The output of the operational amplifier U2C is connected to one of the inputs of the zero-crossing comparator U4. The other input of the zero-crossing comparator U4 is grounded. The zero-crossing comparator forms a square wave conversion link. The sine wave signal After passing through the zero-crossing comparator, the sine wave signal is converted into a signal with the same frequency f s -f0=f s0 +K a A square wave signal of a-f0, which has no relation to temperature and contains only acceleration information.

[0053] like Figure 4The figure shows a schematic diagram of the back-stage principle of the excitation drive module of an embodiment of the present invention. The input end of the CMOS inverter U1D is connected to the output end of the square wave conversion link in the frequency compensation module, and the output end of the CMOS inverter U1D is connected to the input end of the CMOS inverters U1E and U1F. The CMOS inverter U1D alone constitutes an output shaping link to perform waveform shaping on the output signal of the square wave conversion link. The output ends of the CMOS inverters U1E and U1F are connected, which is the output end of the entire excitation drive circuit. The CMOS inverters U1E and U1F are connected in parallel as a drive enhancement link to enhance the load-carrying capacity of the output signal of the excitation drive circuit and keep the phase unchanged.

[0054] The present invention converts the temperature information obtained by measuring the thermistor into a frequency signal in a manner of generating a sine wave through an RC oscillation circuit; reasonably designs the parameters of the RC oscillation circuit so that the magnitude of the frequency signal changing with temperature is consistent with that of a quartz resonant beam; further, a multiplier is used to fuse the sine wave frequency signal with the temperature information with a driving frequency signal, and the temperature change portion is offset through frequency conversion; and then, through notch filtering and waveform conversion, the sine wave signal that is independent of temperature is converted into a CMOS level square wave frequency signal that is more easily received and processed by a digital system, thereby directly reducing the influence of temperature on the quartz resonant beam accelerometer through frequency compensation.

[0055] It should be emphasized that the embodiments described in the present invention are illustrative rather than restrictive. Therefore, the present invention includes but is not limited to the embodiments described in the specific implementation manner. Any other implementation manners derived by those skilled in the art based on the technical solution of the present invention also fall within the scope of protection of the present invention.

Claims

1. A frequency compensation type quartz accelerometer excitation drive circuit, characterized in that: It includes a voltage conversion module, an excitation drive module and a frequency compensation module. The voltage conversion module is connected to the excitation drive module and the frequency compensation module respectively. The front stage of the excitation drive module is connected to the frequency compensation module, and the front stage of the excitation drive module is connected to the rear stage of the excitation drive module. The voltage conversion module is used to convert the external power supply voltage to low voltage and supply power to the excitation drive module and the frequency compensation module. The excitation drive module is connected to a quartz resonant beam to form a closed loop and realize self-oscillation. The frequency compensation module is used to improve the output temperature characteristics of the quartz vibration beam accelerometer.

2. The frequency compensation type quartz accelerometer excitation drive circuit according to claim 1, characterized in that: The input end of the voltage conversion module is directly connected to the external power supply, and the output end is used to provide converted power to the excitation drive module and the frequency compensation module respectively. Through the principle of linear voltage regulation, the high power supply voltage is converted into a low power supply compatible with the CMOS level.

3. The frequency compensation type quartz accelerometer excitation drive circuit according to claim 1, characterized in that: The excitation drive module includes an excitation drive module front stage and an excitation drive module back stage, wherein the excitation drive module front stage includes a linear amplification link, a phase shift amplification link, a gain adjustment and filtering network and a linear amplification and amplitude stabilization link, the linear amplification link, the phase shift amplification link, the gain adjustment and filtering network and the linear amplification and amplitude stabilization link are connected in sequence, the output end of the linear amplification and amplitude stabilization link is respectively connected to the frequency compensation module and the quartz resonant beam, the input end of the linear amplification link is connected to the quartz resonant beam, and the output end of the linear amplification link is connected to the phase shift amplification link; the linear amplification link, the phase shift amplification link, the gain adjustment and filtering network and the linear amplification and amplitude stabilization link and the quartz resonant beam together constitute a closed-loop positive feedback loop, which is used for the oscillation of the quartz resonant beam and meets the amplitude balance and phase balance conditions of continuous oscillation.

4. The frequency compensation type quartz accelerometer excitation drive circuit according to claim 3, characterized in that: The latter stage of the excitation drive module includes an output shaping link and a drive enhancement link, wherein the input end of the output shaping link is connected to the frequency compensation module, the output end of the output shaping link is connected to the drive enhancement link, the drive enhancement link outputs the output signal of the excitation drive circuit, and the output shaping link is used to perform waveform shaping on the signal whose frequency is independent of temperature to improve the signal waveform quality; The drive enhancement link enhances the signal's load-carrying capacity through parallel driving and ensures that the phase remains unchanged, ultimately forming an output signal of the excitation drive circuit.

5. The frequency compensation type quartz accelerometer excitation drive circuit according to claim 1, characterized in that: The frequency compensation module includes a thermistor, a sine wave generating link, a frequency conversion link and a square wave conversion link, wherein the thermistor, the sine wave generating link, the frequency conversion link and the square wave conversion link are connected in sequence, the thermistor is used to realize the temperature measurement of the quartz vibration beam accelerometer head, and is connected to the sine wave generating link as a bridge resistor; the sine wave generating link generates a sine wave signal whose frequency changes linearly with temperature according to the working principle of the RC oscillation circuit; the frequency conversion link realizes the multiplication of the driving signal and the sine wave signal through a multiplier, and obtains a sine wave signal whose frequency is independent of temperature after filtering by a phase shifter and a notch filter; the square wave conversion link converts the sine wave signal whose frequency is independent of temperature into a square wave signal whose frequency is independent of temperature through a zero-crossing comparator and a limiting diode.

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