A method and system for identifying a special tooth speed signal

Abstract

The application discloses a method and system for identifying a special tooth speed signal. A transconductance amplifier circuit receives a speed signal containing a special tooth, converts the speed signal into a current signal, converts the current signal into a voltage signal through a grounding resistor, and outputs the voltage signal to a bias amplifier circuit; the bias amplifier circuit receives a first bias reference voltage, and outputs a single-ended voltage signal to a rectifier follow-up circuit; the rectifier follow-up circuit also receives the first bias reference voltage, completes full-wave rectification and amplitude adjustment, outputs a first signal to a closed-loop control circuit, and outputs a second signal to a waveform judgment circuit; the waveform judgment circuit receives a third bias reference voltage, identifies a special tooth signal in the second signal output signal, and outputs a pulse signal indicating the position of the special tooth; the closed-loop control circuit receives a second bias reference voltage, integrates the first signal output, and outputs a direct current signal to control the amplification coefficient of the transconductance amplifier circuit. The application can identify a special tooth waveform in a wide-frequency wide-amplitude speed signal in real time and accurately.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of aero-engine health management, and particularly relates to a method and system for identifying a special tooth speed signal by automatic gain control. BACKGROUND

[0002] As high-end mechanical and electrical products, aero-engines have complex structure, high technology and high cost. Aero-engine health management (PHM) is a key technology for improving aero-engine integrity, reducing maintenance and support costs, and ensuring flight safety.

[0003] In an aero-engine health management system, rotor phase information is very important and is one of the basic information for completing rotor balancing and vibration analysis. At present, rotor phase information is mainly obtained through a specially processed rotor speed measuring tone wheel. One to three special teeth (i.e. high teeth, short teeth, etc.) are contained in N teeth of the speed measuring tone wheel. When the special (high / short) teeth pass through the speed sensor, the sensing signal waveform generated by the sensor is different from that of other teeth (the waveform amplitude is obviously higher or lower than that of the ordinary teeth), and by identifying the waveform of the special tooth in real time and recording it as a rotor reference phase marker in the vibration signal data, the vibration signal phase information can be obtained, providing necessary input for rotor dynamic balancing test processing. For example, CN109668735A discloses a method for determining an engine rotor phase reference, which comprises: receiving a waveform signal of a current tooth; determining a high tooth feature of the waveform signal of the current tooth according to the waveform signal of the current tooth; obtaining high tooth features of waveform signals of the previous N-1 continuous teeth; and determining that the current tooth is a high tooth when the high tooth feature of the waveform signal of the current tooth is greater than the high tooth features of the waveform signals of the previous N-1 teeth.

[0004] The key to timely and accurate judgment of rotor phase is to be able to identify the special tooth waveform in the speed signal in real time and accurately. However, the signal waveform generated by the speed sensor is related to the speed and the gap between the sensor sensing part and the tone wheel teeth, and the amplitude of the speed signal is not constant but changes with the change of the speed and the gap caused by rotor vibration, and the amplitude of the speed signal can differ by tens of times at most. In the case of low speed, the amplitude of the speed signal is small, which makes it difficult to identify the special tooth waveform.

[0005] Therefore, there is an urgent need for a method and system capable of identifying the special tooth waveform in a wide frequency and wide amplitude speed signal in real time and accurately. SUMMARY

[0006] This summary is provided to introduce some concepts of what will be further described in the detailed description below. This summary does not necessarily describe the key features or essential characteristics of the claimed subject matter. Nor does it necessarily describe required essential features or characteristics of the claimed subject matter.

[0007] The application provides a broadband wide-range speed signal conditioning circuit system with special tooth signals and a method for identifying the special tooth signals in real time.

[0008] The conditioning circuit system for identifying the special tooth speed signals according to the application comprises:

[0009] a transconductance amplifier circuit for receiving the speed signals with special tooth signals and converting the signals into current signals; a bias amplifier circuit for receiving a first bias reference voltage and a voltage signal converted from the current signals from the transconductance amplifier circuit through a grounding resistor and outputting a single-ended voltage signal; a rectification follower circuit for receiving the first bias reference voltage and the single-ended voltage signal from the bias amplifier circuit, completing full-wave rectification and amplitude adjustment, and outputting a first signal and a second signal; a closed-loop control circuit for receiving a second bias reference voltage and the first signal from the rectification follower circuit, integrating the first signal to output a direct current signal for controlling the amplification coefficient of the transconductance amplifier circuit; and a waveform judgment circuit for receiving a third bias reference voltage and the second signal from the rectification follower circuit, identifying the special tooth signal in the second signal, and outputting a pulse signal indicating the position of the special tooth signal.

[0010] The closed-loop control circuit further comprises a U-I conversion circuit and an integration circuit, and the integration circuit receives the second bias reference voltage and the first signal from the rectification follower circuit to integrate the first signal and convert the signal into a direct current signal by the U-I conversion circuit.

[0011] The second bias reference voltage is 125% of the first bias reference voltage, the third bias reference voltage is set according to the maximum value of the normal tooth and the minimum value of the high tooth when the special tooth is a high tooth, and the third bias reference voltage is set according to the minimum value of the normal tooth and the maximum value of the short tooth when the special tooth is a short tooth. Preferably, the first bias reference voltage is 2v, the second bias reference voltage is 2.5v, and the third bias reference voltage is 2.85v.

[0012] The method for identifying the special tooth speed signals according to the application comprises:

[0013] receiving the speed signals with special tooth signals by the transconductance amplifier circuit and converting the signals into current signals; converting the current signals into voltage signals to generate a single-ended voltage signal by applying a first bias reference voltage; completing full-wave rectification and amplitude adjustment by using the first bias reference voltage to generate a first signal and a second signal; and identifying the special tooth signal in the second signal by using a third bias reference voltage and outputting a pulse signal indicating the position of the special tooth signal.

[0014] The present application further comprises integrating the first signal using a second bias reference voltage, outputting a direct current signal as an amplification factor of the transconductance discharge circuit, for negative feedback gain control of the transconductance amplification circuit.

[0015] These and other features and advantages will become apparent to those of ordinary skill in the art upon reading the following detailed description, taken in conjunction with the drawings in which: BRIEF DESCRIPTION OF DRAWINGS

[0016] The present application will be described in greater detail by reading the following detailed description with appropriate reference to the accompanying drawings in which:

[0017] Figure 1 is a circuit diagram of the conditioning circuit system of the automatic gain control identifying high / low tooth speed signals according to the present application;

[0018] Figure 2 is Figure 1 is a special tooth identification schematic diagram of the conditioning circuit system in

[0019] Figure 3 is Figure 2 is an integral closed loop control schematic diagram of the closed loop control circuit in

[0020] Figure 4 is an automatic gain control input / output schematic diagram;

[0021] Figure 5 is a high tooth signal simulation diagram;

[0022] Figure 6 is a low tooth signal simulation diagram. DETAILED DESCRIPTION

[0023] The present application will be described in greater detail by reading the following detailed description with appropriate reference to the accompanying drawings in which: Various advantages and features of novelty are besides those specifically described herein can be apparent from consideration of the description and drawings. It is intended that all such additional advantages and features be within the scope of the following claims. It is to be understood that the following description is only exemplary and intended to provide a description of the methods according to the application. Various changes to the implementations and details thereof can be made without departing from the scope of the application, which is defined by the appended claims. Specific embodiments of the application will now be described in detail with reference to the accompanying drawings.

[0024] Figure 1 and Figure 2 is a circuit diagram of the conditioning circuit system of the automatic gain control identifying high / low tooth speed signals according to the present application and a special tooth identification schematic diagram. Figure 2The conditioning circuit system shown in the figure comprises the following modules: a transconductance amplification circuit 1, a bias amplification circuit 2, a rectification follow-up circuit 3, a closed-loop control circuit 4 and a waveform judgment circuit 5. Figure 1 is and Figure 2 The corresponding exemplary circuit diagram is shown in the figure, wherein the parameter values of the labeled elements are preferred and should not be shown as limiting, and those skilled in the art can understand that the values can be flexibly adjusted according to different engine configurations, and other values that can achieve Figure 2 Other values of the functions of the modules in the figure can also be conceived.

[0025] The connection relationship of the modules of the conditioning circuit system of the present application is as follows:

[0026] One input end of the transconductance amplification circuit 1 is connected to a speed signal containing high / low tooth signals, and the output end of the transconductance amplification circuit 1 is connected to one input end of the bias amplification circuit 2.

[0027] The other input end of the bias amplification circuit 2 is simultaneously connected to a bias reference voltage Uref_b input, and the output end of the bias amplification circuit 2 is connected to one input end of the rectification follow-up circuit 3.

[0028] The other input end of the rectification follow-up circuit 3 is simultaneously connected to a bias reference voltage Uref_b input, the first output end of the rectification follow-up circuit 3 is connected to the input end of the closed-loop control circuit 4, and the second output end of the rectification follow-up circuit 3 is connected to one input end of the waveform judgment circuit 5.

[0029] Figure 3 It is further shown that the closed-loop control circuit 4 comprises a U-I conversion circuit 42 and an integration circuit 41. One input end of the integration circuit 41 is connected to the first output end of the rectification follow-up circuit 3, the other input end of the integration circuit 41 is simultaneously connected to a bias reference voltage Uref_b+ input, the output end of the integration circuit 41 is connected to the input end of the U-I conversion circuit 42, and the output end of the U-I conversion circuit 42 is connected to the other input end of the transconductance amplification circuit 1.

[0030] One input end of the waveform judgment circuit 5 is connected to the second output end of the rectification follow-up circuit 3, the other input end of the waveform judgment circuit 5 is simultaneously connected to a bias reference voltage Uref_c input, and the waveform judgment circuit 5 outputs a high / low tooth identification signal.

[0031] The method for identifying a special tooth speed signal by the automatic gain control of the present application comprises the following steps:

[0032] The speed signal containing high / low teeth (i.e., a differential voltage signal) is input to the transconductance amplification circuit 1, the amplification coefficient of the transconductance amplification circuit 1 is controlled by the bias current I b from the closed-loop control circuit 4, and the transconductance amplification circuit 1 converts the input differential voltage signal into a current signal Io Output, current signal I o The signal is converted into voltage through grounding resistor R19, and after the DC value in the signal is eliminated by capacitor C3, it is sent to bias amplifier circuit 2.

[0033] The bias amplifier circuit 2 has a bias reference voltage of U. ref_b Input ( Figure 1 In the embodiment U ref_b The value is 2v, U refb The value of determines the effective value of the output signal of the rectifier follower circuit 3. After receiving the voltage signal from the transconductance amplifier circuit 1, it outputs a single-ended voltage signal U with a bias voltage of Uref_b. o It should be noted that after the bias amplifier circuit 2 superimposes the bias onto the input signal, the entire output signal is positive. Voltage signal U o The input is fed into rectifier follower circuit 3 via resistor R25;

[0034] Due to U o The bias is U ref_b The AC signal, therefore the rectifier follower circuit 3 also has a bias reference voltage of U. ref_b The input is used to eliminate errors caused by the DC component. The single-ended voltage signal U from the output of the bias amplifier circuit 2 is received. o Then, rectifier follower circuit 3 completes full-wave rectification and amplitude adjustment. Full-wave rectification raises the negative half-cycle of the signal to the positive half-cycle. Figure 1 In this embodiment, the signal peak value is controlled to be around 3V. The first signal U of the rectifier follower circuit 3 f An example of the output waveform of the input closed-loop control circuit 4 is shown in the appendix. Figure 4 As shown in the figure, Figure 4 The automatic gain rectifier circuit in the circuit is equivalent to the aforementioned transconductance amplifier circuit 1 + bias amplifier circuit 2 + rectifier follower circuit 3 + closed-loop control circuit 4. Figure 4 The hysteresis comparator circuit in the middle is equivalent to the waveform judgment circuit 5 mentioned above;

[0035] The integrator circuit 41 in the closed-loop control circuit 4 has a bias reference voltage of U. ref_b+ The input, reference voltage U ref_b+ The setting is U ref_b 125%, the integrating circuit 41 will input signal U f Integrating the signal, the output signal approximates a DC signal I. b DC signal I b It serves as the negative feedback for the entire circuit, used for negative feedback gain control of the transconductance amplifier circuit 1, thereby completing the entire gain closed-loop control. Figure 1 In the embodiment U ref_b+ The value is 2.5V, slightly higher than U. ref_b(2v) is used to prevent U f When the signal amplitude rises at an excessively rapid rate, the circuit can still output normally.

[0036] The second signal U of the rectifier follower circuit 3 c Input waveform judgment circuit 5, waveform judgment circuit 5 has a comparison reference voltage of U ref_c The input (in) Figure 1 In this embodiment, the value is 2.85V. The high / low teeth and normal teeth are identified through a voltage comparison function, i.e., based on the comparison reference voltage U. ref_c Complete the U c The system identifies high / low tooth signals within the signal and outputs a pulse signal indicating the location of the high / low tooth signal. When the special tooth is a high tooth, U... ref_c The settings are based on the following: when the speed signal changes, the high-speed tooth and the normal-speed tooth maintain a fixed ratio, and the reference voltage U is compared. ref_c Setting the value to be greater than the maximum value of a normal tooth and less than the minimum value of a high tooth allows for the identification of high / low teeth from normal teeth. Generally, high teeth have a amplitude 20% higher than normal teeth. Figure 1 In the embodiment, the peak value of the high-speed tooth is around 3V, and the peak value of the ordinary tooth is around 2.5V, so U ref_c Set to 2.85V. When the special tooth is a short tooth, U ref_c The settings are based on the same principle, set according to the minimum value of the standard tooth and the maximum value of the short tooth. Those skilled in the art will understand that this comparison reference voltage U... ref_c Engines with different configurations can be flexibly adjusted.

[0037] Appendix Figure 5 and Figure 6 The results of simulation using simulation software are shown for the speed signal conditioning circuit system containing high / low tooth signals.

[0038] As can be seen, the output signal can quickly and accurately indicate the location of high-tooth or low-tooth signals. When a high-tooth or low-tooth signal appears, the output signal is low, and the output signal corresponding to a normal tooth signal is high, with a stable output result. This indicates that the speed signal conditioning circuit containing high / low-tooth signals can accurately and stably identify high / low-tooth signals.

[0039] This invention achieves gain control of speed signals with wide-bandwidth and wide-amplitude variations based on transconductance amplifiers; achieves closed-loop feedback for stable speed signals based on integral loop feedback; achieves speed signal conditioning based on full-wave rectifier circuits; and adjusts the signal waveform through closed-loop compensation to make the amplitude of ordinary tooth waveforms consistent, while simultaneously determining the differences between special tooth waveforms and ordinary tooth waveforms, thereby improving the accuracy of special tooth waveform identification.

[0040] The above embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit the present application; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that the technical solutions recorded in the foregoing embodiments can still be modified, or some or all of the technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should be covered in the scope of the claims and the description of the present application.

Claims

1. A conditioning circuit system for identifying specific gear speed signals, comprising: A transconductance amplifier circuit (1) is used to receive a rotational speed signal containing special teeth and convert it into a current signal (I). o Output; The bias amplifier circuit (2) is used to receive the first bias reference voltage (U). ref_b ) and the current signal (I) from the transconductance amplifier circuit (1). o The voltage signal after being converted by the grounding resistor is output as a single-ended voltage signal (U). o ); The rectifier follower circuit (3) is used to receive the first bias reference voltage (U). ref_b ) and the single-ended voltage signal (U) from the bias amplifier circuit (2). o This completes full-wave rectification and amplitude adjustment, outputting the first signal (U). f ) and second signal (U c ); Closed-loop control circuit (4) is used to receive the second bias reference voltage (U). ref_b+ ) and the first signal (U) from the rectifier follower circuit (3). f ), will the first signal (U) f After integration, the output DC signal (I) is obtained. b ), used to control the amplification factor of the transconductance amplifier circuit (1); as well as Waveform determination circuit (5) is used to receive the third bias reference voltage (U). ref_c ) and the second signal (U) from the rectifier follower circuit (3). c ), to complete the processing of the second signal (U) c The system identifies special tooth signals within the signal and outputs a pulse signal indicating the location of the special tooth signal. Among them, when the special tooth is a high tooth, the third bias reference voltage (U) ref_c The third bias reference voltage (U) is set according to the maximum value of the ordinary tooth and the minimum value of the high tooth. When the special tooth is a low tooth, the reference voltage is set according to the maximum value of the ordinary tooth and the minimum value of the high tooth. ref_c The value is set based on the minimum value of the normal teeth and the maximum value of the short teeth.

2. The conditioning circuit system as described in claim 1, characterized in that, The second bias reference voltage (U) ref_b+ ) is the first bias reference voltage (U) ref_b 125% of ).

3. The conditioning circuit system as described in claim 1, characterized in that, The closed-loop control circuit (4) further includes a UI conversion circuit (42) and an integrator circuit (41), the integrator circuit receiving a second bias reference voltage (U). ref_b+ ) and the first signal (U) from the rectifier follower circuit (3). f ), to be used for the first signal (U) f After integration, the signal is converted into a DC signal (I) by the UI conversion circuit. b ).

4. The conditioning circuit system as described in claim 1, characterized in that, The first bias reference voltage (U) ref_b The second bias reference voltage (U) is 2V. ref_b+ The third bias reference voltage (U) is 2.5V. ref_c The value is 2.85V.

5. A method for identifying a specific gear speed signal, the method comprising: The transconductance amplifier circuit (1) receives the rotational speed signal containing the special tooth signal and converts it into a current signal (I). o ); The current signal (I) o The signal is converted into voltage, and a single-ended voltage signal (U) is generated by applying a first bias reference voltage. o ); Using the first bias reference voltage (U) ref_b The first signal (U) is generated after full-wave rectification and amplitude adjustment. f ) and second signal (U c ); Using the third bias reference voltage (U) ref_c Complete the processing of the second signal (U) c The system identifies special tooth signals and outputs a pulse signal indicating the location of the special tooth signal. Among them, when the special tooth is a high tooth, the third bias reference voltage (U) ref_c The third bias reference voltage (U) is set according to the maximum value of the ordinary tooth and the minimum value of the high tooth. When the special tooth is a low tooth, the reference voltage is set according to the maximum value of the ordinary tooth and the minimum value of the high tooth. ref_c The value is set based on the minimum value of the normal teeth and the maximum value of the short teeth.

6. The method as described in claim 5, characterized in that, Further includes using a second bias reference voltage (U ref_b+ ) for the first signal (U f Integrate to output a DC signal (I). b ) is used as the amplification factor of the transconductance amplifier circuit and is used for negative feedback gain control of the transconductance amplifier circuit (1).

7. The method as described in claim 6, characterized in that, The second bias reference voltage (U) ref_b+ ) is the first bias reference voltage (U) ref_b 125% of ).

8. The method as described in claim 6, characterized in that, The first bias reference voltage (U) ref_b The second bias reference voltage (U) is 2V. ref_b+ The third bias reference voltage (U) is 2.5V. ref_c The value is 2.85V.

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