阅读说明：本技术 用于感应同步器输出端的前置放大电路及感应同步器 (Pre-amplification circuit for output end of induction synchronizer and induction synchronizer ) 是由 李太平 胡继宝 姜婷 姜守望 孙永雪 于 2021-08-17 设计创作，主要内容包括：本发明提供了一种用于感应同步器输出端的前置放大电路及感应同步器,差分放大电路的输出端与低通滤波电路的输入端连接；低通滤波电路的输出端与带通放大电路的输入端连接；带通放大电路的输出端与全通移相电路的输入端连接。本发明通过差分放大电路将原有的感应同步器输出的差分信号转换为单端信号,提高系统的驱动能力和抗干扰能力,确保了后续的滤波电路的正常工作,满足感应同步器输出特性。(The invention provides a pre-amplification circuit for the output end of an induction synchronizer and the induction synchronizer, wherein the output end of a differential amplification circuit is connected with the input end of a low-pass filter circuit; the output end of the low-pass filter circuit is connected with the input end of the band-pass amplifying circuit; the output end of the band-pass amplifying circuit is connected with the input end of the all-pass phase shifting circuit. According to the invention, the differential signal output by the original induction synchronizer is converted into the single-ended signal through the differential amplification circuit, so that the driving capability and the anti-interference capability of the system are improved, the normal work of the subsequent filter circuit is ensured, and the output characteristic of the induction synchronizer is satisfied.)

1. A pre-amplifier circuit used for the output end of an induction synchronizer is characterized by comprising a differential amplifier circuit, a low-pass filter circuit, a band-pass amplifier circuit and a full-pass phase-shifting circuit;

the input end of the differential amplification circuit is used for receiving signals, and the output end of the differential amplification circuit is connected with the input end of the low-pass filter circuit;

the output end of the low-pass filter circuit is connected with the input end of the band-pass amplifying circuit;

the output end of the band-pass amplifying circuit is connected with the input end of the all-pass phase-shifting circuit, and the output end of the all-pass phase-shifting circuit is used for outputting signals;

the differential amplification circuit is used for converting the original differential signal of the induction synchronizer into a single-ended signal; the low-pass filter circuit is used for further amplifying the signal output by the differential amplifier; the band-pass amplifying circuit is used for filtering high-frequency noise and low-frequency components; the all-pass phase shift circuit is used for adjusting the output phase of the amplified circuit.

2. The preamplifier circuit for sensing the output of a synchronizer of claim 1, wherein the differential amplifier circuit comprises a first amplifier U1, a first resistor R1, a second resistor R2 and a third resistor R3;

two ends of the first resistor R1 are respectively connected to an RG pin of the first amplifier U1;

the second electricityOne end of a resistor R2 is connected with V of the first amplifier U1_IN+A first input terminal on a pin and serving as the first amplifier U1; the other end of the second resistor R2 is respectively connected with the REF pin of the first amplifier U1 and one end of the third resistor R3 and is grounded;

the other end of the third resistor R3 is connected with V of the first amplifier U1_IN-A pin and serves as a second input terminal of the first amplifier U1;

v of the first amplifier U1_OUTA pin serves as the output of the first amplifier U1.

3. The preamplifier circuit for sensing the output of a synchronizer of claim 1, wherein the low pass filter circuit comprises a second amplifier U2, a fourth resistor R4, a fifth resistor R5, a first capacitor C1 and a second capacitor C2;

one end of the fourth resistor R4 is used as the input end of the low-pass filter circuit, and the other end of the fourth resistor R4 is respectively connected to the non-inverting input end of the second amplifier U2, one end of the first capacitor C1 and one end of the fifth resistor R5;

the other end of the first capacitor C1 is grounded; the other end of the fifth resistor R5 is connected with one end of the second capacitor C2; the other end of the second capacitor C2 is connected to the output end of the second amplifier U2 and the negative-phase input end of the second amplifier U2 respectively and serves as the output end of the low-pass filter circuit.

4. The preamplifier circuit for sensing the output of a synchronizer of claim 1, wherein the band-pass amplifier circuit comprises a third amplifier U3, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a third capacitor C3 and a fourth capacitor C4;

one end of the sixth resistor R6 is used as the input end of the band-pass amplifying circuit, and the other end of the sixth resistor R6 is connected to one end of the third capacitor C3, one end of the fourth capacitor C4, and one end of the seventh resistor R7, respectively;

the other end of the third capacitor C3 is respectively connected to one end of the eighth resistor R8 and the output end of the third amplifier U3 and serves as the output end of the band-pass amplifying circuit;

the other end of the fourth capacitor C4 is respectively connected with the other end of the eighth resistor R8 and the negative-phase input end of the third amplifier U3;

the other end of the seventh resistor R7 is connected to the non-inverting input of the third amplifier U3 and to ground.

5. The pre-amplifier circuit of claim 1, wherein the all-pass phase shift circuit comprises a fourth amplifier U4, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, and a fifth capacitor C5;

one end of the ninth resistor R9 is connected to one end of the fifth capacitor C5 and serves as an input end of an all-pass phase shift circuit, and the other end of the ninth resistor R9 is connected to one end of the tenth resistor R10 and a negative-phase input end of the fourth amplifier U4 respectively;

the other end of the tenth resistor R10 is connected to the output end of the fourth amplifier U4 and serves as the output end of the all-pass phase shift circuit;

the other end of the fifth capacitor C5 is respectively connected to the non-inverting input end of the fourth amplifier U4 and one end of the eleventh resistor R11;

the other end of the eleventh resistor R11 is grounded.

6. The preamplifier circuit for sensing an output of a synchronizer of claim 1, wherein an amplification of the differential amplifier circuit is not less than 100.

7. The pre-amplifier circuit of claim 1, wherein the amplification in the passband of the low pass filter circuit is not less than 10.

8. The pre-amplifier circuit of claim 1, wherein the amplification in the bandpass amplifier circuit bandpass is no more than 3.

9. The preamplifier circuit for the output end of the induction synchronizer according to claim 1, wherein the amplification factor of the all-pass phase shift circuit is 1, and the phase shift mode of the all-pass phase shift circuit is to adjust the capacity of the capacitor.

10. An inductive synchronizer comprising a preamplifier circuit for an output of an inductive synchronizer according to any of claims 1 to 9.

Technical Field

The invention relates to the technical field of automatic control and measurement, in particular to a preamplifier circuit for an output end of an induction synchronizer and the induction synchronizer.

Background

With the increasing life of the spacecraft and the increasing and improving precision of the movable parts on the spacecraft, the precision and reliability of the angle measuring element are also increased, and angle measuring parts represented by circular gratings and encoders are gradually replaced by induction synchronizers in partial applications due to the difficulty in ensuring the long service life and high reliability of the angle measuring parts in an on-orbit mode.

The post-processing module of the induction synchronizer is generally implemented by using a special chip of Analog Device. However, the output signal of the induction synchronizer is very weak, the peak-to-peak value is not more than 5mV, and a special chip or a digital circuit generally needs the peak-to-peak value of the input signal to be 5V, so that the output signal needs to be effectively amplified. Meanwhile, signal phase shift is inevitably caused in the amplification process, and the working principle of the induction synchronizer determines that two output ends and a reference signal of the induction synchronizer need to meet a certain phase relation, so that the pre-processing circuit needs to perform phase shift. The pre-processing circuit is generally formed by connecting two low-pass and phase-shifting circuits in series, but when the method is adopted, the driving capability of the induction synchronizer is very weak, the induction synchronizer is easily interfered by noise on a ground plane, meanwhile, in order to realize larger amplification factor, a plurality of stages of low-pass filters are required to be connected in series, and some low-frequency interference cannot be effectively filtered.

The patent document with publication number CN110864620A discloses a device for improving signal-to-noise ratio of an induction synchronizer signal, and relates to the field of angle measurement of induction synchronizers, the device includes a preceding stage amplifying circuit, the preceding stage amplifying circuit includes a signal input terminal IN1, a signal input terminal IN2, a high-precision matching pipe U1, a triode Q and a diode D, the signal input terminal IN1 and the signal input terminal IN2 are connected with an output winding of the induction synchronizer, resistors R3 and R4 are connected IN series with a potentiometer RP1 to form a zero adjusting circuit, and the triode Q, the diode D, a resistor R5, a resistor R6 and a resistor R7 form a constant current source circuit. However, the patent document still has the defect of poor interference filtering effect.

Disclosure of Invention

In view of the defects in the prior art, the present invention provides a preamplifier circuit for an output terminal of an induction synchronizer and the induction synchronizer.

The invention provides a pre-amplification circuit for an output end of an induction synchronizer, which comprises a differential amplification circuit, a low-pass filter circuit, a band-pass amplification circuit and a full-pass phase-shifting circuit;

the input end of the differential amplification circuit is used for receiving signals, and the output end of the differential amplification circuit is connected with the input end of the low-pass filter circuit;

the output end of the low-pass filter circuit is connected with the input end of the band-pass amplifying circuit;

the output end of the band-pass amplifying circuit is connected with the input end of the all-pass phase-shifting circuit, and the output end of the all-pass phase-shifting circuit is used for outputting signals;

the differential amplification circuit is used for converting the original differential signal of the induction synchronizer into a single-ended signal; the low-pass filter circuit is used for further amplifying the signal output by the differential amplifier; the band-pass amplifying circuit is used for filtering high-frequency noise and low-frequency components; the all-pass phase shift circuit is used for adjusting the output phase of the amplified circuit.

Preferably, the differential amplifier circuit includes a first amplifier U1, a first resistor R1, a second resistor R2, and a third resistor R3;

two ends of the first resistor R1 are respectively connected to an RG pin of the first amplifier U1;

one end of the second resistor R2 is connected to V of the first amplifier U1_IN+A first input terminal on a pin and serving as the first amplifier U1; the other end of the second resistor R2 is respectively connected with the REF pin of the first amplifier U1 and one end of the third resistor R3 and is grounded;

the other end of the third resistor R3 is connected with V of the first amplifier U1_IN-A pin and serves as a second input terminal of the first amplifier U1;

v of the first amplifier U1_OUTA pin serves as the output of the first amplifier U1.

Preferably, the low-pass filter circuit comprises a second amplifier U2, a fourth resistor R4, a fifth resistor R5, a first capacitor C1 and a second capacitor C2;

one end of the fourth resistor R4 is used as the input end of the low-pass filter circuit, and the other end of the fourth resistor R4 is respectively connected to the non-inverting input end of the second amplifier U2, one end of the first capacitor C1 and one end of the fifth resistor R5;

the other end of the first capacitor C1 is grounded; the other end of the fifth resistor R5 is connected with one end of the second capacitor C2; the other end of the second capacitor C2 is connected to the output end of the second amplifier U2 and the negative-phase input end of the second amplifier U2 respectively and serves as the output end of the low-pass filter circuit.

Preferably, the band-pass amplifying circuit includes a third amplifier U3, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a third capacitor C3 and a fourth capacitor C4;

one end of the sixth resistor R6 is used as the input end of the band-pass amplifying circuit, and the other end of the sixth resistor R6 is connected to one end of the third capacitor C3, one end of the fourth capacitor C4, and one end of the seventh resistor R7, respectively;

the other end of the third capacitor C3 is respectively connected to one end of the eighth resistor R8 and the output end of the third amplifier U3 and serves as the output end of the band-pass amplifying circuit;

the other end of the fourth capacitor C4 is respectively connected with the other end of the eighth resistor R8 and the negative-phase input end of the third amplifier U3;

the other end of the seventh resistor R7 is connected to the non-inverting input of the third amplifier U3 and to ground.

Preferably, the all-pass phase shift circuit comprises a fourth amplifier U4, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11 and a fifth capacitor C5;

one end of the ninth resistor R9 is connected to one end of the fifth capacitor C5 and serves as an input end of an all-pass phase shift circuit, and the other end of the ninth resistor R9 is connected to one end of the tenth resistor R10 and a negative-phase input end of the fourth amplifier U4 respectively;

the other end of the tenth resistor R10 is connected to the output end of the fourth amplifier U4 and serves as the output end of the all-pass phase shift circuit;

the other end of the fifth capacitor C5 is respectively connected to the non-inverting input end of the fourth amplifier U4 and one end of the eleventh resistor R11;

the other end of the eleventh resistor R11 is grounded.

Preferably, the amplification factor of the differential amplification circuit is not less than 100.

Preferably, the amplification factor in the passband of the low-pass filter circuit is not less than 10.

Preferably, the amplification factor in the band pass of the band pass amplification circuit is not more than 3.

Preferably, the amplification factor of the all-pass phase shift circuit is 1, and the phase shift mode of the all-pass phase shift circuit is to adjust the capacity of the capacitor.

The invention also provides an induction synchronizer which comprises the preamplifier circuit used for the output end of the induction synchronizer.

Compared with the prior art, the invention has the following beneficial effects:

1. according to the invention, the differential signal output by the original induction synchronizer is converted into the single-ended signal through the differential amplification circuit, so that the driving capability and the anti-interference capability of a system are improved, the normal work of a subsequent filter circuit is ensured, and the output characteristic of the induction synchronizer is met;

2. according to the invention, high-frequency noise and low-frequency components are further filtered by the band-pass filter, so that the signal-to-noise ratio is improved;

3. the invention adjusts the output phase of the amplified circuit through the all-pass phase shift circuit, so that the output phase meets the requirements of a rear-end demodulation circuit and precision.

Drawings

Other features, objects and advantages of the invention will become more apparent upon reading of the detailed description of non-limiting embodiments with reference to the following drawings:

FIG. 1 is a block diagram of a preamplifier circuit for an output of an inductive synchronizer according to the present invention;

FIG. 2 is a connection diagram of a differential amplifier circuit of the present invention;

FIG. 3 is a schematic diagram of a low pass filter circuit of the present invention;

FIG. 4 is a schematic diagram of the bandpass amplification circuit of the present invention;

FIG. 5 is a schematic diagram of an all-pass phase shift circuit of the present invention.

Detailed Description

The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the invention, but are not intended to limit the invention in any way. It should be noted that it would be obvious to those skilled in the art that various changes and modifications can be made without departing from the spirit of the invention. All falling within the scope of the present invention.

As shown in fig. 1 to 5, the pre-amplifier circuit for the output terminal of the induction synchronizer according to the present invention comprises a differential amplifier circuit and a low-pass filter circuit, the band-pass amplifier comprises a band-pass amplifier circuit and a full-pass phase-shifting circuit, wherein the input end of the differential amplifier circuit is used for receiving signals, the output end of the differential amplifier circuit is connected with the input end of a low-pass filter circuit, the output end of the low-pass filter circuit is connected with the input end of the band-pass amplifier circuit, the output end of the band-pass amplifier circuit is connected with the input end of the full-pass phase-shifting circuit, the output end of the full-pass phase-shifting circuit is used for outputting signals, the differential amplifier circuit is used for converting the differential signals of an original induction synchronizer into single-ended signals, the low-pass filter circuit is used for further amplifying the signals output by the differential amplifier, the band-pass amplifier circuit is used for filtering high-frequency noise and low-frequency components, and the full-pass phase-shifting circuit is used for adjusting the output phase of the amplified circuit.

The amplification factor of the differential amplification circuit is not less than 100. The amplification factor in the band of the low-pass filter circuit is not less than 10. The amplification factor in a passband of the bandpass amplification circuit is not more than 3. The amplification factor of the all-pass phase-shift circuit is 1, and the phase-shift mode of the all-pass phase-shift circuit is to adjust the capacity of the capacitor.

The differential amplifying circuit comprises a first amplifier U1, a first resistor R1, a second resistor R2 and a third resistor R3, wherein two ends of the first resistor R1 are respectively connected with the second resistor R3An amplifier U1 having an RG pin, and a second resistor R2 with one end connected to V of the first amplifier U1_IN+The pin is connected with a first input end of a first amplifier U1, the other end of the second resistor R2 is respectively connected with the REF pin of the first amplifier U1 and one end of a third resistor R3 and is grounded, and the other end of the third resistor R3 is connected with the V of the first amplifier U1_IN-Pin and as a second input of the first amplifier U1, V of the first amplifier U1_OUTThe pin serves as the output of the first amplifier U1.

The low-pass filter circuit comprises a second amplifier U2, a fourth resistor R4, a fifth resistor R5, a first capacitor C1 and a second capacitor C2, one end of the fourth resistor R4 serves as an input end of the low-pass filter circuit, the other end of the fourth resistor R4 is connected with a non-inverting input end of the second amplifier U2, one end of the first capacitor C1 and one end of the fifth resistor R5 respectively, and the other end of the first capacitor C1 is grounded; the other end of the fifth resistor R5 is connected to one end of the second capacitor C2, and the other end of the second capacitor C2 is connected to the output end of the second amplifier U2 and the negative-phase input end of the second amplifier U2 respectively and serves as the output end of the low-pass filter circuit.

The band-pass amplifying circuit comprises a third amplifier U3, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a third capacitor C3 and a fourth capacitor C4, wherein one end of the sixth resistor R6 is used as an input end of the band-pass amplifying circuit, the other end of the sixth resistor R6 is respectively connected with one end of the third capacitor C3, one end of the fourth capacitor C4 and one end of the seventh resistor R7, the other end of the third capacitor C3 is respectively connected with one end of the eighth resistor R8 and an output end of the third amplifier U3 and is used as an output end of the band-pass amplifying circuit, the other end of the fourth capacitor C4 is respectively connected with the other end of the eighth resistor R8 and a negative phase input end of the third amplifier U3, and the other end of the seventh resistor R7 is connected with a positive phase input end of the third amplifier U3 and is grounded.

The all-pass phase shift circuit comprises a fourth amplifier U4, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11 and a fifth capacitor C5, wherein one end of the ninth resistor R9 is connected with one end of the fifth capacitor C5 and serves as an input end of the all-pass phase shift circuit, the other end of the ninth resistor R9 is connected with one end of the tenth resistor R10 and a negative phase input end of the fourth amplifier U4, the other end of the tenth resistor R10 is connected with an output end of the fourth amplifier U4 and serves as an output end of the all-pass phase shift circuit, the other end of the fifth capacitor C5 is connected with a positive phase input end of the fourth amplifier U4 and one end of the eleventh resistor R11, and the other end of the eleventh resistor R11 is grounded.

The differential amplification circuit converts the original differential signal of the induction synchronizer into a single-ended signal, so that the driving capability and the anti-interference capability of a system are improved, the normal work of a subsequent filter circuit is ensured, and the output characteristic of the induction synchronizer is met. The rear end of the differential amplifying circuit is connected with a low-pass filter circuit, so that the amplification factor is further improved. The back end of the low-pass filter circuit is connected with a band-pass amplifying circuit, so that high-frequency noise and low-frequency components are further filtered, and the signal-to-noise ratio is improved. The rear end of the band-pass amplifying circuit is connected with a full-pass phase shifting circuit, and the output phase of the amplified circuit is adjusted by adjusting the capacitance value of the adjustable capacitor, so that the requirements of a rear-end demodulation circuit and precision are met.

In fig. 1, a differential amplifying circuit, a low-pass filter circuit, a band-pass amplifying circuit and a full-pass phase-shifting circuit are connected in series.

In FIG. 2, a differential amplifier circuit is shown, wherein U1 suggests an instrument amplifier, S₊、S_{_}Respectively, the voltage at the differential input, i.e. the voltage at the output of the induction synchronizer, V₁The input and the output of the voltage at the output end satisfy the following conditions:

R₀is a coefficient related to the U1 model, wherein R₁The specific size is subsequently determined according to the overall magnification of the system,is not less than 100 to improve the signal-to-noise ratio at the input.

FIG. 3 is a low pass filter, V₁Is the voltage at its input, V₂The voltage of the output end is the voltage of the output end, and the output and the input of the output end meet the following conditions:

wherein s denotes s in Laplace transformation, and the magnification is not less than 10.

FIG. 4 shows a band-pass filter, V₂Is the voltage at its input, V₃The voltage of the output end is the voltage of the output end, and the output and the input of the output end meet the following conditions:

the design magnification was 1.

FIG. 5 is a full pass phase shift circuit, V₃Is the voltage at its input, V₄The voltage of the output end is the voltage of the output end, and the output and the input of the output end meet the following conditions:

R₉＝R₁₀so it becomes:

after the low-pass filter circuit finishes the circuit board pasting, the output end and a reference signal (given by an excitation signal of the induction synchronizer) are connected to the oscilloscope, and C is adjusted₄The phase of each output end of the induction synchronizer meets the relation with the reference signal, and simultaneously meets the phase relation between the two output ends of the induction synchronizer. After the phase meets the requirement, the R of the differential amplifying circuit is adjusted₁And the amplitude of the output end meets the requirement of a back-end special chip.

The invention also provides an induction synchronizer which comprises the preamplifier circuit used for the output end of the induction synchronizer.

According to the invention, the differential signal output by the original induction synchronizer is converted into the single-ended signal through the differential amplification circuit, so that the driving capability and the anti-interference capability of the system are improved, the normal work of the subsequent filter circuit is ensured, and the output characteristic of the induction synchronizer is satisfied.

The foregoing description of specific embodiments of the present invention has been presented. It is to be understood that the present invention is not limited to the specific embodiments described above, and that various changes or modifications may be made by one skilled in the art within the scope of the appended claims without departing from the spirit of the invention. The embodiments and features of the embodiments of the present application may be combined with each other arbitrarily without conflict.