Isolated variable-frequency electromagnetic pendulum driving circuit

Abstract

In order to overcome the defects of poor anti-interference capability and weak load driving capability of an electromagnetic pendulum driving circuit in the existing scheme for improving the zero-bias stability of a mechanical inertial sensor with a built-in bearing, the utility model provides an isolated variable-frequency electromagnetic pendulum driving circuit, which comprises a triode conditioning circuit for generating control square waves, the control circuit is used for controlling on-off of the isolation circuit; the isolation circuit is used for realizing isolation between a control end and a driving end and generating a unipolar driving excitation signal based on the control square wave; the amplitude adjusting circuit is used for adjusting the unipolar driving excitation signal into a bipolar square wave; and the transistor switch control circuit is used for generating a driving signal of which the frequency is consistent with that of the control square wave according to the bipolar square wave. The isolating circuit isolates the front-end control signal from the rear-end driving signal, so that signal interference is effectively reduced. The driving signal finally generated by the transistor switch control circuit comes from the power supply, so that the driving loading capacity is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to electronic equipment drive application technical field. BACKGROUND

[0002] The performance requirement of the inertial sensor is higher and higher for the aircraft navigation and control system, so that the inertial sensor needs to improve the measurement precision, stability and reliability and other indexes. For the mechanical inertial sensor with built-in bearing, the zero offset error is large due to the axial support friction torque in the structure, which greatly restricts the improvement of the zero offset stability.

[0003] In order to reduce the friction torque of the axial support, the design parameters of the axial support are optimized, the high-precision bearing is selected and the electromagnetic swing structure is added in the prior art. Among them, due to the limitation of domestic process, it is difficult to realize the measures of reducing the friction torque by optimizing the design parameters of the axial support and selecting the high-precision bearing; and the internal electromagnetic swing structure of the sensor is based on the principle of limited angle torque motor, and the bearing outer ring is driven to swing at a small angle, so as to reduce the starting friction torque, dynamic friction torque and friction torque fluctuation value of the bearing, so as to greatly eliminate the error caused by the axial support friction torque. In order to drive the periodic swing of the electromagnetic swing structure, the direct drive type circuit is generally used in the prior art, which is easy to be interfered by electromagnetic interference, and has weak load driving capacity, which restricts the improvement of high precision and high reliability of the inertial sensor. UTILITY MODEL CONTENTS

[0004] In order to solve the shortcomings of poor anti-interference ability and weak load driving capacity of the electromagnetic swing driving circuit in the prior art for improving the zero offset stability performance of the mechanical inertial sensor with built-in bearing, the utility model provides an isolated variable frequency electromagnetic swing driving circuit as part of the external control circuit of the mechanical inertial sensor.

[0005] The technical scheme of the utility model is:

[0006] An isolated variable frequency electromagnetic swing driving circuit, characterized in that: it comprises a triode conditioning circuit, an isolation circuit, an amplitude adjustment circuit and a transistor switch control circuit.

[0007] The triode conditioning circuit is used for generating a control square wave and controlling the on-off of the isolation circuit.

[0008] The isolation circuit is used for realizing the isolation of the control end and the driving end, and generating a unipolar driving excitation signal based on the control square wave.

[0009] The amplitude adjustment circuit is used for adjusting the unipolar driving excitation signal into a bipolar square wave.

[0010] The transistor switch control circuit is used for generating a driving signal with a frequency size consistent with the control square wave according to the bipolar square wave.

[0011] Further, the triode conditioning circuit comprises a processor ARM, a crystal triode Q4, resistors R1 and R2; the control square wave generated by the processor ARM is input to the resistor R2, when the control square wave makes the resistor R2 end in suspension or low level, the resistor R1 makes the crystal triode Q4 in the cut-off state; when the control square wave makes the resistor R2 end in high level, the voltage division of the resistor R1 makes the crystal triode Q4 conduct; the crystal triode Q4 realizes the switch on-off with the same frequency of the control square wave with the voltage change of the control square wave, thereby controlling the on-off of the isolation circuit.

[0012] Further, the isolation circuit comprises a current limiting resistor R6, a photoelectric coupler U1 and a voltage dividing resistor R3; the current limiting resistor R6 is connected between the power supply VDD and the photoelectric coupler U1, and is used for protecting the photoelectric coupler U1; the on-off of the photoelectric coupler U1 is controlled by the on-off of the crystal triode Q4, and the unipolar driving excitation signal is output: when the crystal triode Q4 conducts, the photoelectric coupler U1 conducts, and the voltage dividing resistor R3 makes the driving excitation signal output by the photoelectric coupler U1 be high level; when the crystal triode Q4 is cut off, the photoelectric coupler U1 does not conduct, and the voltage dividing resistor R3 makes the driving excitation signal output by the photoelectric coupler U1 be low level.

[0013] Further, the amplitude adjustment circuit comprises an operational amplifier U2A and resistors R7 and R8; the resistors R7 and R8 are used for forming a reference voltage; the operational amplifier U2A is used for comparing the driving excitation signal output by the photoelectric coupler U1 with the reference voltage, and outputting the bipolar square wave according to the voltage comparison result.

[0014] Further, the transistor switch control circuit comprises crystal triodes Q2 and Q3, an N-channel field effect transistor Q1, a P-channel field effect transistor Q5, and voltage dividing resistors R10, R11, R21 and R22; the crystal triodes Q2 and Q3 are triggered to conduct at different times by the high and low levels of the bipolar square wave, so that the P-channel field effect transistor Q5 and the N-channel field effect transistor Q1 are conducted at different times: when the crystal triode Q2 conducts, the voltage division of the voltage dividing resistor R10 makes the N-channel field effect transistor Q1 conduct; when the crystal triode Q3 conducts, the voltage division of the voltage dividing resistor R11 makes the P-channel field effect transistor Q5 conduct; the N-channel field effect transistor Q1 and the P-channel field effect transistor Q5 output the driving signal with the frequency size consistent with the control square wave.

[0015] The beneficial effects of the present application are:

[0016] 1. In order to improve the electromagnetic pendulum drive circuit anti-interference ability and load driving ability, the utility model discloses an isolation type variable frequency electromagnetic pendulum drive circuit, generates the drive signal (the drive signal is the fixed frequency square wave excitation signal) for driving the periodic motion of the internal electromagnetic pendulum structure of mechanical inertia sensor, through the fixed frequency square wave excitation signal of the utility model output to the coil of the electromagnetic pendulum, makes the polarity periodic change of the magnetic pole in the coil, drives the periodic swing of the bearing outer ring, thereby reduces the axial support friction torque, greatly eliminates the error caused by the friction torque, improves the output zero bias stability of the built-in bearing mechanical inertia sensor.

[0017] 2. The utility model discloses an isolation type variable frequency electromagnetic pendulum drive circuit based on processor, crystal triode, photoelectric coupler, operational amplifier and N / P field effect transistor realizes. Processor generates fixed frequency control signal, adopts the on-off characteristic of crystal triode to realize the on-off control of photoelectric coupler to processor, realizes the isolation transmission of frequency control signal sent by processor, according to the photoelectric transmission characteristic of photoelectric coupler, isolates the front-end control signal and rear-end drive signal, effectively reduces signal interference, indirectly controls the switch on of rear-end N / P field effect transistor through the frequency control signal of processor, and the frequency of frequency control signal is consistent with the drive frequency of electromagnetic pendulum, therefore, can adjust the frequency size of frequency control signal of processor adaptively, provides different drive frequency for electromagnetic pendulum structure, satisfies the different requirements of different inertia sensor to electromagnetic pendulum swing frequency, reduces the error, realizes the on-off switching of ± 5V power supply through the switch on characteristic of N / P field effect transistor, finally outputs ± 5V drive signal, since ± 5V drive signal is directly from the power supply ± 5V, therefore effectively improves the drive load capacity.

[0018] 3. The utility model discloses the input is the frequency control signal provided by processor, can adjust the frequency size adaptively, is favorable to the swing frequency of debugging sensor internal electromagnetic pendulum structure, reduces the error.

[0019] 4. The utility model discloses circuit principle simple, logic is strong, applicability is wide, load driving ability is strong. SHEET

[0020] Figure 1 It is the circuit diagram of the utility model isolation type variable frequency electromagnetic pendulum drive circuit.

[0021] Figure 2 It is the simulation diagram of the utility model isolation type variable frequency electromagnetic pendulum drive circuit.

[0022] Figure 3 It is the simulation result of the utility model isolation type variable frequency electromagnetic pendulum drive circuit. SPECIFIC EMBODIMENT

[0023] The utility model is further described in detail below with reference to the drawings.

[0024] With reference to Figure 1 The isolation type variable-frequency electromagnetic swing driving circuit provided by the utility model comprises a triode conditioning circuit, an isolation circuit, an amplitude adjustment circuit and a transistor switch control circuit.

[0025] The triode conditioning circuit is used for generating a control square wave of a certain frequency and for controlling the on-off of the isolation circuit, mainly comprising a processor ARM, a crystal triode Q4, resistors R1 and R2, wherein the control square wave CT (0-3.3V) generated by the processor ARM is input to the resistor R2, when the control square wave CT makes the resistor R2 end be in suspension or low level, the resistor R1 makes the crystal triode Q4 be in the off state, when the control square wave CT makes the resistor R2 be in high level, the voltage division of the resistor R1 makes the crystal triode Q4 be in conduction; the control square wave CT (0-3.3V) of a certain frequency (the frequency size can be adjusted by the processor according to the swing frequency requirement of the electromagnetic swing of the driving circuit adapted inertia sensor) is generated by the front-end processor ARM, and the crystal triode Q4 realizes the on-off switching of the same frequency with the control square wave with the voltage change of the control square wave CT (0-3.3V).

[0026] The isolation circuit is used for realizing the isolation of the control end and the driving end, and generating a unipolar driving excitation signal based on the control square wave generated by the triode conditioning circuit. The isolation circuit comprises a current-limiting resistor R6, a photoelectric coupler U1 and a voltage dividing resistor R3. The current-limiting resistor R6 is connected between the power supply VDD and the photoelectric coupler U1, and is used for protecting the photoelectric coupler U1; the on-off of the photoelectric coupler U1 is controlled by the on-off of the crystal triode Q4, the photoelectric coupler U1 outputs a driving excitation signal (0-5V square wave): when the control square wave is high, the crystal triode Q4 is in conduction, the photoelectric coupler U1 is in conduction, and the voltage dividing resistor R3 makes the driving excitation signal output by the photoelectric coupler U1 be high (5V); when the control square wave is low, the crystal triode Q4 is cut off, the photoelectric coupler U1 is not in conduction, and the voltage dividing resistor R3 makes the driving excitation signal output by the photoelectric coupler U1 be low (0V).

[0027] The amplitude adjusting circuit is mainly used for adjusting the single polarity drive excitation signal into a bipolar square wave, and mainly realizes voltage comparison and amplitude adjustment function based on the operational amplifier U2A, resistors R7, R8, R4, R16 and capacitor C4; according to the open loop characteristic of the operational amplifier U2A, the drive excitation signal (0-5V square wave) output by the photoelectric coupler U1 is compared with the reference voltage (2.5V) composed of the resistors R7 and R8, when the drive excitation signal is high (5V), the open loop output of the operational amplifier is "+3.5V", when the drive excitation signal is low (0V), the open loop output of the operational amplifier is "-3.5V", so that the single polarity drive excitation signal (0-5V square wave) is adjusted into a bipolar square wave (±3.5V); the resistor R4 is used for calibrating bias current and improving the operational amplifier precision of the operational amplifier U2A; the resistor R16 and the capacitor C4 constitute a filter circuit.

[0028] The transistor switch control circuit is used for generating a drive signal with the same frequency as the control square wave according to the bipolar square wave. The transistor switch control circuit comprises transistors Q2, Q3, field effect transistors Q1 and Q5, and voltage dividing resistors R10, R11, R21 and R22; the transistors Q2 and Q3 are triggered to conduct at different times by the high and low levels of the bipolar square wave (±3.5V), so that the P-channel field effect transistor Q5 and the N-channel field effect transistor Q1 are conducted at different times; when the transistor Q2 is conducted, the voltage division of the voltage dividing resistor R10 makes the N-channel field effect transistor Q1 conducted, and when the transistor Q3 is conducted, the voltage division of the voltage dividing resistor R11 makes the P-channel field effect transistor Q5 conducted. The field effect transistors Q1 and Q5 finally output a drive signal DRIVE (-5VJL~+5VJL square wave signal) with the same frequency as the control square wave, which is isolated from the front-end control square wave and has high driving capacity to drive the electromagnetic pendulum inside the rear-end sensor.

[0029] Figures 2-3 For the simulation circuit diagram and simulation results of the isolation type variable frequency electromagnetic pendulum drive circuit, a signal generator is used to input a 500Hz, 0-3.3V square wave, and an oscilloscope is used to test the output as a -5V~+5V square wave.

Claims

1. An isolated variable frequency electromagnetic pendulum drive circuit, characterized by: The triode regulating circuit, the isolation circuit, the amplitude adjusting circuit and the transistor switch control circuit are included. The triode regulating circuit is used for generating a control square wave and controlling the on-off of the isolation circuit. The isolation circuit is used for realizing the isolation between the control end and the driving end and generating a unipolar driving excitation signal based on the control square wave. The amplitude adjusting circuit is used for adjusting the unipolar driving excitation signal into a bipolar square wave. The transistor switch control circuit is used for generating a driving signal with the same frequency and size as the control square wave according to the bipolar square wave.

2. The isolated variable frequency electromagnetic pendulum drive circuit according to claim 1, characterized in that: The triode regulating circuit includes a processor ARM, a crystal triode Q4, resistors R1 and R2. The control square wave generated by the processor ARM is input to the resistor R2. When the control square wave makes the resistor R2 end in suspension or low level, the resistor R1 makes the crystal triode Q4 in the cut-off state. When the control square wave makes the resistor R2 end in high level, the voltage division of the resistor R1 makes the crystal triode Q4 conduct. The crystal triode Q4 realizes the on-off switching with the same frequency as the control square wave with the voltage change of the control square wave, thereby controlling the on-off of the isolation circuit.

3. The isolated variable frequency electromagnetic pendulum drive circuit of claim 2, wherein: The isolation circuit includes a current limiting resistor R6, a photoelectric coupler U1 and a voltage dividing resistor R3. The current limiting resistor R6 is connected between the power supply VDD and the photoelectric coupler U1, and is used for protecting the photoelectric coupler U1. The on-off of the photoelectric coupler U1 is controlled by the on-off of the crystal triode Q4, and the photoelectric coupler U1 outputs the unipolar driving excitation signal. When the crystal triode Q4 is conductive, the photoelectric coupler U1 is conductive, and the voltage dividing resistor R3 makes the driving excitation signal output by the photoelectric coupler U1 in high level. When the crystal triode Q4 is cut off, the photoelectric coupler U1 is not conductive, and the voltage dividing resistor R3 makes the driving excitation signal output by the photoelectric coupler U1 in low level.

4. The isolated variable-frequency electromagnetic pendulum drive circuit according to claim 3, characterized in that: The amplitude adjusting circuit includes an operational amplifier U2A and resistors R7 and R8. The resistors R7 and R8 are used for forming a reference voltage. The operational amplifier U2A is used for comparing the driving excitation signal output by the photoelectric coupler U1 with the reference voltage, and outputting the bipolar square wave according to the voltage comparison result.

5. The isolated variable-frequency electromagnetic pendulum drive circuit according to claim 4, characterized in that: The transistor switch control circuit includes crystal triodes Q2 and Q3, an N-channel field effect transistor Q1, a P-channel field effect transistor Q5, and voltage dividing resistors R10, R11, R21 and R22. The crystal triodes Q2 and Q3 are triggered to conduct at different times by the high and low levels of the bipolar square wave, so that the P-channel field effect transistor Q5 and the N-channel field effect transistor Q1 are not conductive at the same time. When the crystal triode Q2 is conductive, the voltage division of the voltage dividing resistor R10 makes the N-channel field effect transistor Q1 conductive. When the crystal triode Q3 is conductive, the voltage division of the voltage dividing resistor R11 makes the P-channel field effect transistor Q5 conductive. The N-channel field effect transistor Q1 and the P-channel field effect transistor Q5 output the driving signal with the same frequency and size as the control square wave.

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