Novel dynamic parameter measuring device and method for hydraulic high-speed switch valve

Abstract

The invention provides a novel dynamic parameter measuring device and method for a hydraulic high-speed switch valve. The novel dynamic parameter measuring device comprises a super-radiation luminescence light source, an optical fiber coupler, a reference arm, a detection arm, the hydraulic high-speed switch valve, a spectrograph and an upper computer. Near-infrared light of the super-radiation light-emitting light source is coupled into the optical fiber coupler and then is divided into reference light and detection light used for detecting a sample, and the reference light enters the reference arm and then is reflected by the plane mirror in the reference arm and returns to the optical fiber coupler. The detection light is focused on the end face of an armature of the high-speed switch valve (9) through the detection arm, reflected and returned to the optical fiber coupler, the reference light and the detection light return to the optical fiber coupler interfere in the optical fiber coupler, and a generated interference signal is collected by the grating spectrometer (11) and then transmitted to the upper computer. The upper computer processes the interference signals to measure dynamic parameters of the high-speed switch valve; according to the invention, high-precision dynamic parameter measurement of the high-speed switch valve can be realized under a non-contact condition.

Description

Technical Field

[0001] The present invention relates to, in particular, a novel dynamic parameter measuring device and method of a hydraulic high-speed switching valve. Background Art

[0002] High-speed on-off valve is a precision fluid control element that uses digital on-off control instead of valve opening throttling control. It can greatly reduce the throttling loss of the valve control system, improve the anti-pollution ability of the electro-hydraulic control system, and realize hydraulic digitization and high-reliability control. The high-speed on-off valve changes the output discrete fluid flow by adjusting the duty cycle of the PWM signal to achieve regulation and control of the loop system. Its operating frequency can reach more than 400Hz. High-speed on-off valves are widely used in aero engines, oil drilling equipment and other fields due to their fast response speed and low cost. High-speed on-off valves achieve precise control of flow by adjusting the vibration frequency, duty cycle and amplitude of the armature in the valve body. Therefore, monitoring these dynamic parameters has become a very important task in the design process of high-speed on-off valves.

[0003] There are many methods for measuring the dynamic parameters of high-speed switch valves. The traditional methods for measuring the dynamic parameters of high-speed switch valves include: pressure test method, displacement sensor method, acceleration sensor vibration signal method, flow test method, etc. However, the measurement equipment of these traditional methods is close to the target to be measured, and they all have direct or indirect contact with the target to be measured. The frequency measurement range is limited and the anti-electromagnetic interference ability is weak. When measuring a high-speed switch valve with a small stroke, the unstable jitter of the vibration meter itself will cause a large measurement error. When measuring a high-speed switch valve with a small stroke, the unstable jitter of the vibration meter itself will cause a large measurement error. Secondly, the installed vibration sensor will change the original quality of the valve core, and the change in the quality of the valve core will change its action response time, and ultimately affect the linearity of the output and the flow rate. Therefore, the traditional mechanical measurement method is not suitable for monitoring high-speed switch valves.

[0004] Optical measurement belongs to non-contact measurement. The new optical non-contact method for measuring the dynamic parameters of hydraulic high-speed switch valves can avoid the problems of traditional mechanical measurement. This method indirectly obtains the macroscopic or microscopic vibration information of the measured target by measuring the amplitude, phase, frequency, measurement angle or polarization state of the modulated echo light. Since it can achieve high-precision and high-real-time contactless vibration measurement, it has been widely used in precision measurement engineering and has great application prospects in the dynamic parameter measurement of high-speed switch valves. The new hydraulic high-speed switch valve dynamic parameter measurement device and method proposed by the present invention has the following technical advantages:

[0005] 1. Low cost and small size: Frequency domain optical coherence vibrometer technology can use broadband light source. Compared with other optical non-contact detection methods, it has the advantages of low cost and small size.

[0006] 2. High-precision measurement: This technology is based on the principle of low-coherence light interference and has the advantages of low cost, high measurement accuracy, and non-destructiveness. It can well meet the requirements of precision vibration measurement. The measurement accuracy reaches the nanometer level.

[0007] 3. Wide applicability: Frequency domain optical coherence vibrometer technology is suitable for a variety of application scenarios, including thermal deformation detection, rotating structure vibration measurement, etc. These fields have a high demand for non-contact measurement methods.

[0008] 4. High stability: Frequency domain optical coherence vibrometer technology can provide high-precision displacement measurement, and effective vibration measurement can be achieved by recording the measurement time. The system has high measurement accuracy and good stability.

[0009] Therefore, a new type of dynamic parameter measurement device and method for hydraulic high-speed switching valve is proposed. Summary of the invention

[0010] The present invention provides a novel device and method for measuring dynamic parameters of a hydraulic high-speed switching valve, which can realize high-precision dynamic parameter measurement of a high-speed switching valve in a non-contact situation.

[0011] The present invention adopts the following technical solutions.

[0012] A novel dynamic parameter measuring device for a hydraulic high-speed switch valve comprises: a super radiant light source, a fiber coupler, a reference arm, a detection arm, a hydraulic high-speed switch valve, a spectrometer, and a host computer; after the near-infrared light of the super radiant light source is coupled into the fiber coupler, it is divided into reference light and detection light for detecting a sample; after the reference light enters the reference arm, it is reflected by a plane reflector in the reference arm and returns to the fiber coupler; the detection light is focused on the armature end face of the high-speed switch valve (9) through the detection arm, is reflected and returns to the fiber coupler; the reference light and the detection light returning to the fiber coupler interfere with each other in the fiber coupler; the generated interference signal is collected by a grating spectrometer (11) and transmitted to the host computer; the host computer processes the interference signal to measure the dynamic parameters of the high-speed switch valve.

[0013] The super luminescent light source is an SLD broadband light source (1), comprising a super luminescent diode capable of emitting near infrared light.

[0014] The optical fiber coupler is a 2×2 optical fiber coupler; the superluminescent diode emits near-infrared light with a central wavelength of 880nm and a bandwidth of 70nm.

[0015] The reference arm is provided with a reference arm optical fiber FC-APC connector (2), a reference arm collimating lens (3), a reference arm focusing lens (4), and a plane reflector in sequence at its optical path, wherein the plane reflector is a reference arm gold-plated plane reflector (5);

[0016] The detection arm is provided with a detection arm optical fiber FC-APC connector (6), a detection arm collimating lens (7), and a detection arm focusing lens (8) in sequence at its optical path;

[0017] The grating spectrometer is provided with a spectrometer optical fiber connector (10), a grating spectrometer collimating lens (12), a grating spectrometer reflective ruled diffraction grating (13), a grating spectrometer focusing lens (14), and a high-speed linear array CCD camera (15) in sequence at the input optical path;

[0018] The host computer is a computer (16).

[0019] A novel method for measuring dynamic parameters of hydraulic high-speed switching valves, using the above-mentioned device for measuring dynamic parameters of hydraulic high-speed switching valves, is characterized in that it comprises the following steps:

[0020] Step S1, a superluminescent diode radiates a near-infrared light source which enters a fiber coupler and is divided into a reference light and a detection light for scanning a high-speed switch valve sample;

[0021] Step S2, fixing the position of the detection arm so that the detection light is focused onto the armature end face of the high-speed switch valve;

[0022] Step S3, the detection light returned from the armature cross section meets and couples with the reference light at the fiber coupler to form an interference signal, which is converted into an electrical signal by the spectrometer and input into the host computer;

[0023] Step S4: Use the energy center correction method to process the collected sequence of interference signals to obtain the time-vibration displacement data of the armature section of the high-speed switch valve, and calculate various dynamic parameters of the switch valve.

[0024] In step S1, the light from the light source enters the reference arm through the optical fiber FC connector, becomes parallel light after passing through the collimating lens, and then is focused on the upper surface of the gold-plated plane reflector by the focusing lens to form the reference light that is finally reflected back into the optical fiber coupler;

[0025] In step S2, the structure of the detection arm is the same as that of the reference arm. The light from the light source enters the detection arm through the optical fiber FC connector, and then enters the high-speed switch valve, and is reflected by the metal interface inside the cavity of the high-speed switch valve to form a detection light that is finally reflected back to the optical fiber coupler. The detection light and the reference light that return to the optical fiber coupler interfere with each other in the optical fiber coupler to form an interference signal, which is collected by a grating spectrometer.

[0026] The interference signal is collimated into parallel light by the collimating lens of the grating spectrometer, and then split by the reflection grating. It is focused on the linear array CCD photosensitive element of the high-speed linear array CCD camera under the action of the focusing lens. The high-speed linear array CCD camera collects the spectral information and transmits it back to the computer for data processing.

[0027] In step S4, the CCD sampling frequency of the high-speed linear array CCD camera is set to 25000 Hz, the high-speed switching valve is turned on to put the valve body in a working state, and its working frequencies are set to 50 Hz, 90 Hz, 200 Hz, 300 Hz, 400 Hz, 500 Hz, 600 Hz, and 700 Hz, respectively. The frequency domain optical coherence vibration measurement system is used to collect the corresponding interference signal under this condition. At this time, the interference signal includes the dynamic parameters of the corresponding high-speed switching valve at different frequencies.

[0028] In step S4, the amplitude, vibration frequency, duty cycle and displacement nonlinear error of the switch valve are calculated.

[0029] In step S4, the host computer starts the frequency domain optical coherence vibration measurement system, and collects interference signals from the high-speed switch valves in the working state of 50 Hz, 90 Hz, 200 Hz, 300 Hz, 400 Hz, 500 Hz, 600 Hz, and 700 Hz respectively; performs spectral correction and fast Fourier transform on the eight groups of interference signals collected; uses the Hanning window energy center of gravity correction method to obtain the peak data after the fast Fourier transform, converts it into displacement information and draws the displacement time curve;

[0030] Specifically, the Hanning window energy center of gravity correction algorithm is:

[0031]

[0032] in, is the normalized frequency of the harmonic signal, k is the spectral line number corresponding to the maximum point of the spectral line amplitude, G is the amplitude corresponding to the i-th spectral line, f s is the sampling frequency, and N is the number of sampling points.

[0033] In step S4, the host computer obtains the interference signal of the high-speed switch valve through the frequency domain optical coherence vibrometer, draws the time-displacement curve, and calculates the amplitude, vibration frequency, working duty cycle and displacement nonlinear error of the switch valve related dynamic parameters; specifically:

[0034] Assume x1 is the initial vibration position of the high-speed switch valve, x2 is the position of the high-speed switch valve at time t, and Lx is the displacement; as time t changes during the operation of the high-speed switch valve, the displacement Lx will also change with time t, and the specific signal change is reflected in the density change of the interference signal; the interference signal at the above starting position and time t is subjected to Fourier transform and spectrum correction to obtain the displacement change that occurs at time t, thereby establishing the Lx-t displacement time curve.

[0035] Compared with the prior art, the present invention and its preferred solution can realize a high-precision dynamic parameter measurement method for high-speed switch valves in a non-contact situation through frequency domain optical coherence vibration measurement technology, overcoming the problems of limited frequency measurement range and weak anti-electromagnetic interference ability of the traditional mechanical measurement method, as well as the problem that the unstable jitter of the vibration meter itself will cause large measurement errors when measuring high-speed switch valves with small strokes. This method has great application potential in the measurement of dynamic parameters of high-speed switch valves.

[0036] The novel hydraulic high-speed switch valve dynamic parameter measurement device and method proposed by the present invention has the following technical advantages:

[0037] 1. Low cost and small size: Frequency domain optical coherence vibrometer technology can use broadband light source. Compared with other optical non-contact detection methods, it has the advantages of low cost and small size.

[0038] 2. High-precision measurement: This technology is based on the principle of low-coherence light interference and has the advantages of low cost, high measurement accuracy, and non-destructiveness. It can well meet the requirements of precision vibration measurement. The measurement accuracy reaches the nanometer level.

[0039] 3. Wide applicability: Frequency domain optical coherence vibrometer technology is suitable for a variety of application scenarios, including thermal deformation detection, rotating structure vibration measurement, etc. These fields have a high demand for non-contact measurement methods.

[0040] 4. High stability: Frequency domain optical coherence vibrometer technology can provide high-precision displacement measurement, and effective vibration measurement can be achieved by recording the measurement time. The system has high measurement accuracy and good stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments:

[0042] Attached Figure 1 Schematic diagram of the structure principle of the frequency domain optical coherence vibration measurement system in an embodiment of the present invention;

[0043] Attached Figure 2 Schematic diagram of a high-speed switch valve measured in an embodiment of the present invention;

[0044] Attached Figure 3 Schematic diagram of the displacement time curve of the high-speed switching valve at different operating frequencies collected in step S4 in an embodiment of the present invention;

[0045] Attached Figure 4 Schematic diagram of peak signal-to-noise ratio curve of frequency domain optical coherence vibrometer system in an embodiment of the present invention;

[0046] Attached Figure 5 Schematic diagram of vibration displacement nonlinear error curve in an embodiment of the present invention;

[0047] Attached Figure 6 Schematic diagram of amplitude results collected at a vibration frequency of 50 Hz for a high-speed switching valve in an embodiment of the present invention;

[0048] Attached Figure 7 A schematic diagram showing comparison of measurement results of high-speed switching valves with different duty cycles in an embodiment of the present invention;

[0049] Attached Figure 8 It is a schematic diagram of a method for drawing a time-displacement curve in step S4 and calculating relevant dynamic parameters such as amplitude, vibration frequency, duty cycle and displacement nonlinear error;

[0050] In the figure: 1 is an SLD broadband light source, 2 is a reference arm optical fiber FC-APC connector, 3 is a reference arm collimating lens, 4 is a reference arm focusing lens, 5 is a reference arm gold-plated plane reflector, 6 is a detection arm optical fiber FC-APC connector, 7 is a detection arm collimating lens, 8 is a detection arm focusing lens, 9 is a high-speed switching valve, 10 is a spectrometer optical fiber connector, 11 is a grating spectrometer, 12 is a grating spectrometer collimating lens, 13 is a grating spectrometer reflection ruled diffraction grating, 14 is a grating spectrometer focusing lens, 15 is a high-speed linear array CCD camera, and 16 is a computer. DETAILED DESCRIPTION

[0051] In order to make the features and advantages of this patent more obvious and easy to understand, the following embodiments are specifically described in detail as follows:

[0052] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used in this specification have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0053] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0054] As shown in the figure, a novel dynamic parameter measuring device for a hydraulic high-speed switching valve is provided, the measuring device comprising: a super radiant luminescent light source, a fiber coupler, a reference arm, a detection arm, a hydraulic high-speed switching valve, a spectrometer, and a host computer; after the near-infrared light of the super radiant luminescent light source is coupled into the fiber coupler, it is divided into a reference light and a detection light for detecting a sample; after the reference light enters the reference arm, it is reflected by a plane reflector in the reference arm and returns to the fiber coupler; the detection light is focused on the armature end face of the high-speed switching valve 9 by the detection arm, is reflected and returns to the fiber coupler; the reference light and the detection light returning to the fiber coupler interfere with each other in the fiber coupler; the generated interference signal is collected by a grating spectrometer 11 and transmitted to the host computer; the host computer processes the interference signal to measure the dynamic parameters of the high-speed switching valve.

[0055] The super luminescent light source is an SLD broadband light source 1, which includes a super luminescent diode that can emit near-infrared light.

[0056] The optical fiber coupler is a 2×2 optical fiber coupler; the superluminescent diode emits near-infrared light with a central wavelength of 880nm and a bandwidth of 70nm.

[0057] The reference arm is provided with a reference arm optical fiber FC-APC connector 2, a reference arm collimating lens 3, a reference arm focusing lens 4, and a plane reflector in sequence at its optical path, wherein the plane reflector is a reference arm gold-plated plane reflector 5;

[0058] The detection arm is provided with a detection arm optical fiber FC-APC connector 6, a detection arm collimating lens 7, and a detection arm focusing lens 8 in sequence at its optical path;

[0059] The grating spectrometer is provided with a spectrometer optical fiber connector 10, a grating spectrometer collimating lens 12, a grating spectrometer reflective ruled diffraction grating 13, a grating spectrometer focusing lens 14, and a high-speed linear array CCD camera 15 in sequence at the input optical path;

[0060] The host computer is a computer 16 .

[0061] A novel method for measuring dynamic parameters of hydraulic high-speed switching valves, using the above-mentioned device for measuring dynamic parameters of hydraulic high-speed switching valves, is characterized in that it comprises the following steps:

[0062] Step S1, a superluminescent diode radiates a near-infrared light source which enters a fiber coupler and is divided into a reference light and a detection light for scanning a high-speed switch valve sample;

[0063] Step S2, fixing the position of the detection arm so that the detection light is focused onto the armature end face of the high-speed switch valve;

[0064] Step S3, the detection light returned from the armature cross section meets and couples with the reference light at the fiber coupler to form an interference signal, which is converted into an electrical signal by the spectrometer and input into the host computer;

[0065] Step S4: Use the energy center correction method to process the collected sequence of interference signals to obtain the time-vibration displacement data of the armature section of the high-speed switch valve, and calculate various dynamic parameters of the switch valve.

[0066] In step S1, the light from the light source enters the reference arm through the optical fiber FC connector, becomes parallel light after passing through the collimating lens, and then is focused on the upper surface of the gold-plated plane reflector by the focusing lens to form the reference light that is finally reflected back into the optical fiber coupler;

[0067] In step S2, the structure of the detection arm is the same as that of the reference arm. The light from the light source enters the detection arm through the optical fiber FC connector, and then enters the high-speed switch valve, and is reflected by the metal interface inside the cavity of the high-speed switch valve to form a detection light that is finally reflected back to the optical fiber coupler. The detection light and the reference light that return to the optical fiber coupler interfere with each other in the optical fiber coupler to form an interference signal, which is collected by a grating spectrometer.

[0068] The interference signal is collimated into parallel light by the collimating lens of the grating spectrometer, and then split by the reflection grating. It is focused on the linear array CCD photosensitive element of the high-speed linear array CCD camera under the action of the focusing lens. The high-speed linear array CCD camera collects the spectral information and transmits it back to the computer for data processing.

[0069] In step S4, the CCD sampling frequency of the high-speed linear array CCD camera is set to 25000 Hz, the high-speed switching valve is turned on to put the valve body in a working state, and its working frequencies are set to 50 Hz, 90 Hz, 200 Hz, 300 Hz, 400 Hz, 500 Hz, 600 Hz, and 700 Hz, respectively. The frequency domain optical coherence vibration measurement system is used to collect the corresponding interference signal under this condition. At this time, the interference signal includes the dynamic parameters of the corresponding high-speed switching valve at different frequencies.

[0070] In step S4, the amplitude, vibration frequency, duty cycle and displacement nonlinear error of the switch valve are calculated.

[0071] In step S4, the host computer starts the frequency domain optical coherence vibration measurement system, and collects interference signals from the high-speed switch valves in the working state of 50 Hz, 90 Hz, 200 Hz, 300 Hz, 400 Hz, 500 Hz, 600 Hz, and 700 Hz respectively; performs spectral correction and fast Fourier transform on the eight groups of interference signals collected; uses the Hanning window energy center of gravity correction method to obtain the peak data after the fast Fourier transform, converts it into displacement information and draws the displacement time curve;

[0072] Specifically, the Hanning window energy center of gravity correction algorithm is:

[0073]

[0074] in, is the normalized frequency of the harmonic signal, k is the spectral line number corresponding to the maximum point of the spectral line amplitude, G is the amplitude corresponding to the i-th spectral line, f s is the sampling frequency, and N is the number of sampling points.

[0075] In step S4, the host computer obtains the interference signal of the high-speed switch valve through the frequency domain optical coherence vibrometer, draws the time-displacement curve, and calculates the amplitude, vibration frequency, working duty cycle and displacement nonlinear error of the switch valve related dynamic parameters; specifically:

[0076] Assume x1 is the initial vibration position of the high-speed switch valve, x2 is the position of the high-speed switch valve at time t, and Lx is the displacement; as time t changes during the operation of the high-speed switch valve, the displacement Lx will also change with time t, and the specific signal change is reflected in the density change of the interference signal; the interference signal at the above starting position and time t is subjected to Fourier transform and spectrum correction to obtain the displacement change that occurs at time t, thereby establishing the Lx-t displacement time curve.

[0077] Example:

[0078] This embodiment provides a method for measuring dynamic parameters of a high-speed switch valve based on frequency domain optical coherence vibration measurement technology, comprising the following steps:

[0079] S1. A novel high-speed switch valve measuring device mainly comprises a frequency domain optical coherence vibration measurement system and a high-speed switch valve;

[0080] In this embodiment, if Figure 1As shown, the frequency domain optical coherence vibrometer system includes: 1 is an SLD broadband light source, 2 is a reference arm optical fiber FC connector, 3 is a reference arm collimating lens, 4 is a reference arm focusing lens, 5 is a reference arm gold-plated plane reflector, 6 is a detection arm including an optical fiber FC connector, 7 is a detection arm collimating lens, 8 is a detection arm focusing lens, 9 is a high-speed switching valve, 10 is a spectrometer optical fiber connector, 11 is a grating spectrometer, 12 is a grating spectrometer collimating lens, 13 is a grating spectrometer reflection ruled diffraction grating, 14 is a grating spectrometer focusing lens, 15 is a high-speed linear array CCD camera, and 16 is a computer. The optical path of the frequency domain optical coherence vibration measurement system is as follows: a near-infrared light source with a central wavelength of 880nm and a bandwidth of 70nm is emitted by a superluminescent diode. The light source enters from one end of a 2×2 optical fiber coupler and is divided into reference light and sample light (detection light). After the reference light enters the reference arm, it is reflected by the gold-plated plane reflector in the reference arm. The detection light is focused on the end face of the armature of the high-speed switch valve through the detection arm and is reflected by the end face of the armature. The two beams of light return to the optical fiber coupler and interfere in the optical fiber coupler. Finally, the interference signal is collected by a grating spectrometer.

[0081] S2. Fix the high-speed switch valve on the detection arm of the frequency domain optical coherence vibration measurement system, and measure multiple dynamic parameters of the high-speed switch valve under different working conditions; open the high-speed switch valve to put the valve body in the working state; set the working frequency of the high-speed switch valve to 50Hz, 90Hz, 200Hz, 300Hz, 400Hz, 500Hz, 600Hz, and 700Hz respectively;

[0082] The frequency domain optical coherence vibration measurement system is turned on to collect interference signals of high-speed switch valves under working conditions of 50Hz, 90Hz, 200Hz, 300Hz, 400Hz, 500Hz, 600Hz, and 700Hz respectively; the eight groups of interference signals collected are spectrally corrected and fast Fourier transformed; the peak data after S7 fast Fourier transform is obtained using the Hanning window energy center of gravity correction method, which is converted into displacement information and the displacement time curve is plotted. Specifically, the Hanning window energy center of gravity correction algorithm is:

[0083]

[0084] in, is the normalized frequency of the harmonic signal, k is the spectral line number corresponding to the maximum point of the spectral line amplitude, G is the amplitude corresponding to the i-th spectral line, f s is the sampling frequency, and N is the number of sampling points.

[0085] S3. The dynamic parameters measured by a new type of dynamic parameter measurement device for hydraulic high-speed switching valve include: amplitude, vibration frequency, duty cycle and displacement nonlinear error.

[0086] S4. Obtain the interference signal of the high-speed switch valve under operation by the frequency domain optical coherence vibrometer, draw the time-displacement curve, and calculate the amplitude, vibration frequency, working duty cycle, displacement nonlinear error and other related dynamic parameters;

[0087] In step S4, the method for drawing the time-displacement curve and calculating the amplitude, vibration frequency, duty cycle, displacement nonlinear error and other related dynamic parameters is specifically embodied as follows:

[0088] As shown in the figure below, x1 is the initial test position of the high-speed switch valve vibration, x2 is the position of the high-speed switch valve at time t, and Lx is the displacement. During the operation of the high-speed switch valve, as time t changes, the displacement Lx will also change with time t, and the specific signal is reflected in the density change of the interference signal. By performing Fourier transform and spectrum correction on the above starting position and the interference signal at time t, the displacement change at time t can be obtained, and the Lx-t displacement time curve can be established.

[0089] A set of interference signals with a time of t and a displacement of Lx are processed. Since the spectrum signal at time t will undergo periodic changes in the amplitude range during the operation of the high-speed switching valve, the switching valve working at a fixed frequency is sampled for multiple cycles, and a periodic point in the spectrum signal is extracted as the observation object to establish a time-displacement curve. The amplitude of the high-speed switching valve at the corresponding operating frequency can be easily obtained.

[0090] Assuming that the displacement change period in the obtained time displacement curve is T and the frequency is f, then f=1 / T, the actual operating frequency and duty cycle can be measured, and the nonlinear error analysis of the actual operating frequency obtained by the system and the set operating frequency can be performed to obtain the nonlinear error curve.

[0091] According to the above method, in an application example of this embodiment, eight operating frequencies of 50 Hz, 90 Hz, 200 Hz, 300 Hz, 400 Hz, 500 Hz, 600 Hz, and 700 Hz are selected from the operating frequency of the high-speed switch valve, and interference signals are collected for the high-speed switch valves under the eight operating frequencies. Figure 2 is a high-speed switching valve measured in an embodiment of the present invention, Figure 3 Figure 1 is a schematic diagram of the displacement time curve of the high-speed switching valve at different operating frequencies. Table 1 is the measurement results of different operating frequencies collected by the system.

[0092] Table 1 Calculation results of high-speed switching valves at different operating frequencies

[0093]

[0094] The signal-to-noise ratio curve of the frequency domain optical coherence vibrometer system used in this embodiment is as follows: Figure 4, the peak signal-to-noise ratio PSNR is 106dB. Figure 5 This is the vibration displacement nonlinear error curve, and the nonlinear error is 0.0668%. Figure 6 This is the amplitude result graph collected at a vibration frequency of 50 Hz for this high-speed switching valve, with an amplitude of 180.744 μm.

[0095] The duty cycle of the high-speed switch valve (the ratio of the time of the high level (or activation state) in the control signal to the entire cycle time) is set to 10%, 30%, and 50%. The frequency domain optical coherence vibration measurement system is used to perform interference signal sampling detection on the three duty cycles respectively. The results are shown in the figure below. Table 2 shows the detection results of different duty cycle settings.

[0096] Table 2 Test results of high-speed switching valves with different duty ratios

[0097]

[0098] The frequency domain optical coherence vibrometer system was used to measure the high-speed switching valve at different operating frequencies and different duty cycles. The nonlinear error obtained was only 0.0668%. The experimental system has a high signal-to-noise ratio and has great application prospects in the dynamic parameter detection of high-speed switching valves. The experimental results prove the feasibility and accuracy of this method.

[0099] The above experiments and results show that the method proposed in the present invention can non-destructively measure the dynamic parameters of high-speed switching valves with high precision, and has strong practicality and broad application prospects.

[0100] The above are only preferred embodiments of the present invention, and are not intended to limit the present invention in other forms. Any technician familiar with the profession may use the above disclosed technical content to change or modify it into an equivalent embodiment with equivalent changes. However, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the technical solution of the present invention still falls within the protection scope of the technical solution of the present invention.

[0101] This patent is not limited to the above-mentioned optimal implementation mode. Anyone can derive other forms of high-speed switch valve dynamic parameter measurement methods based on frequency domain optical coherence vibration measurement technology under the inspiration of this patent. All equal changes and modifications made according to the scope of the patent application of the present invention should be covered by this patent.

Claims

1. A new type of dynamic parameter measurement device for hydraulic high-speed switching valve, characterized in that: The measuring device comprises: a super radiant luminescence light source, a fiber coupler, a reference arm, a detection arm, a hydraulic high-speed switch valve, a spectrometer, and a host computer; after the near-infrared light of the super radiant luminescence light source is coupled into the fiber coupler, it is divided into reference light and detection light for detecting a sample; after the reference light enters the reference arm, it is reflected by a plane reflector in the reference arm and returns to the fiber coupler; the detection light is focused on the armature end face of the high-speed switch valve (9) through the detection arm, is reflected and returns to the fiber coupler; the reference light and the detection light returning to the fiber coupler interfere with each other in the fiber coupler; the generated interference signal is collected by a grating spectrometer (11) and then transmitted to the host computer; the host computer processes the interference signal to measure the dynamic parameters of the high-speed switch valve.

2. According to claim 1, a novel hydraulic high-speed switch valve dynamic parameter measuring device is characterized in that: The super luminescent light source is an SLD broadband light source (1), comprising a super luminescent diode capable of emitting near infrared light.

3. A novel hydraulic high-speed switch valve dynamic parameter measuring device according to claim 2, characterized in that: The optical fiber coupler is a 2×2 optical fiber coupler; the superluminescent diode emits near-infrared light with a central wavelength of 880nm and a bandwidth of 70nm.

4. A novel hydraulic high-speed switch valve dynamic parameter measuring device according to claim 2, characterized in that: The reference arm is provided with a reference arm optical fiber FC-APC connector (2), a reference arm collimating lens (3), a reference arm focusing lens (4), and a plane reflector in sequence at its optical path, wherein the plane reflector is a reference arm gold-plated plane reflector (5); The detection arm is provided with a detection arm optical fiber FC-APC connector (6), a detection arm collimating lens (7), and a detection arm focusing lens (8) in sequence at its optical path; The grating spectrometer is provided with a spectrometer optical fiber connector (10), a grating spectrometer collimating lens (12), a grating spectrometer reflective ruled diffraction grating (13), a grating spectrometer focusing lens (14), and a high-speed linear array CCD camera (15) in sequence at the input optical path; The host computer is a computer (16).

5. A novel method for measuring dynamic parameters of a hydraulic high-speed switching valve, using the hydraulic high-speed switching valve dynamic parameter measuring device according to claim 4, characterized in that: The steps include: Step S1, a superluminescent diode radiates a near-infrared light source which enters a fiber coupler and is divided into a reference light and a detection light for scanning a high-speed switch valve sample; Step S2, fixing the position of the detection arm so that the detection light is focused onto the armature end face of the high-speed switch valve; Step S3, the detection light returned from the armature cross section meets and couples with the reference light at the fiber coupler to form an interference signal, which is converted into an electrical signal by the spectrometer and input into the host computer; Step S4: Use the energy center correction method to process the collected sequence of interference signals to obtain the time-vibration displacement data of the armature section of the high-speed switch valve, and calculate various dynamic parameters of the switch valve.

6. The novel method for measuring dynamic parameters of hydraulic high-speed switching valve according to claim 5 is characterized in that: In step S1, the light from the light source enters the reference arm through the optical fiber FC connector, becomes parallel light after passing through the collimating lens, and then is focused on the upper surface of the gold-plated plane reflector by the focusing lens to form the reference light that is finally reflected back into the optical fiber coupler; In step S2, the structure of the detection arm is the same as that of the reference arm. The light from the light source enters the detection arm through the optical fiber FC connector, and then enters the high-speed switch valve, and is reflected by the metal interface inside the cavity of the high-speed switch valve to form a detection light that is finally reflected back to the optical fiber coupler. The detection light and the reference light that return to the optical fiber coupler interfere with each other in the optical fiber coupler to form an interference signal, which is collected by a grating spectrometer. The interference signal is collimated into parallel light by the collimating lens of the grating spectrometer, and then split by the reflection grating. It is focused on the linear array CCD photosensitive element of the high-speed linear array CCD camera under the action of the focusing lens. The high-speed linear array CCD camera collects the spectral information and transmits it back to the computer for data processing.

7. The novel method for measuring dynamic parameters of hydraulic high-speed switching valve according to claim 5 is characterized in that: In step S4, the CCD sampling frequency of the high-speed linear array CCD camera is set to 25000 Hz, the high-speed switching valve is turned on to put the valve body in a working state, and its working frequencies are set to 50 Hz, 90 Hz, 200 Hz, 300 Hz, 400 Hz, 500 Hz, 600 Hz, and 700 Hz, respectively. The frequency domain optical coherence vibration measurement system is used to collect the corresponding interference signal under this condition. At this time, the interference signal includes the dynamic parameters of the corresponding high-speed switching valve at different frequencies.

8. The novel method for measuring dynamic parameters of hydraulic high-speed switching valve according to claim 7 is characterized in that: In step S4, the amplitude, vibration frequency, duty cycle and displacement nonlinear error of the switch valve are calculated.

9. The novel method for measuring dynamic parameters of hydraulic high-speed switching valve according to claim 7 is characterized in that: In step S4, the host computer starts the frequency domain optical coherence vibration measurement system, and collects interference signals from the high-speed switch valves in the working state of 50 Hz, 90 Hz, 200 Hz, 300 Hz, 400 Hz, 500 Hz, 600 Hz, and 700 Hz respectively; performs spectral correction and fast Fourier transform on the eight groups of interference signals collected; uses the Hanning window energy center of gravity correction method to obtain the peak data after the fast Fourier transform, converts it into displacement information and draws the displacement time curve; Specifically, the Hanning window energy center of gravity correction algorithm is: in, is the normalized frequency of the harmonic signal, k is the spectral line number corresponding to the maximum point of the spectral line amplitude, G is the amplitude corresponding to the i-th spectral line, f s is the sampling frequency, and N is the number of sampling points.

10. The novel method for measuring dynamic parameters of hydraulic high-speed switching valve according to claim 9 is characterized in that: In step S4, the host computer obtains the interference signal of the high-speed switch valve through the frequency domain optical coherence vibrometer, draws the time-displacement curve, and calculates the amplitude, vibration frequency, working duty cycle and displacement nonlinear error of the switch valve related dynamic parameters; specifically: Assume x1 is the initial vibration position of the high-speed switch valve, x2 is the position of the high-speed switch valve at time t, and Lx is the displacement; as time t changes during the operation of the high-speed switch valve, the displacement Lx will also change with time t, and the specific signal change is reflected in the density change of the interference signal; the interference signal at the above starting position and time t is subjected to Fourier transform and spectrum correction to obtain the displacement change that occurs at time t, thereby establishing the Lx-t displacement time curve.

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