A nonlinear chatter control method considering high dynamic low hysteresis loop and micro-motion characteristics of proportional valve

Abstract

The application discloses a nonlinear chatter control method considering high dynamic low hysteresis loop and micro-motion characteristics of a proportional valve, and belongs to the proportional valve control field. The application obtains a detection signal of a controlled proportional valve in real time, carries out mean filtering processing on the real-time detection signal to filter out a chatter part, and obtains a basic detection signal; a controller obtains a pre-valve and post-valve pressure difference of a current proportional valve, a target control signal current and the basic detection signal; the frequency and amplitude of a driving control signal and an optimal chatter control signal are obtained; the driving control signal and the chatter control signal complete addition operation in the controller to obtain an equivalent control signal, and the control of the controlled proportional valve is realized. The application method is applied to a closed loop feedback link, and can greatly reduce the hysteresis loop. Under the control method of the application, the valve core will always be in a macro-stable and micro-dithering state, so the speed of responding to the control signal is faster, the dead zone and saturation zone range of the proportional valve current-displacement curve will be reduced, and the linearity is higher.

Description

Technical Field

[0001] The present invention belongs to the field of proportional valve control, and in particular relates to a nonlinear flutter control method that takes into account high dynamic, low hysteresis and micro-motion characteristics of the proportional valve. Background Art

[0002] Due to the spool structure of a proportional valve, friction inevitably occurs between the valve core and the valve body during movement. Friction is one of the main causes of proportional valve hysteresis. When the proportional valve receives a motion control signal, the valve core must overcome static friction, which is greater than the dynamic friction, to move from a stationary state. At this point, a larger drive current must be supplied to the solenoid coil to generate a greater driving force to counteract the static friction and achieve initial valve core displacement. This impeded valve core movement can lead to problems such as proportional valve dead zone, poor micro-motion characteristics, valve core displacement hysteresis, and flow rate hysteresis. This reduces the repeatability of the proportional valve's open-loop control system and can cause oscillation or even failure in the closed-loop control system.

[0003] The main causes of proportional valve hysteresis include friction, spring deformation hysteresis effect, hysteresis effect, fluid dynamic effect, mechanical clearance and assembly error, and temperature change. Under ideal conditions, the relationship between valve core displacement and coil current should be as follows: Figure 1 However, in actual working conditions, the coil current-valve core displacement curve when the valve core extends and retracts is as follows Figure 2 As shown in the figure, when the valve core extends, the valve core does not move until the coil current reaches a certain level, forming a dead zone. When the coil current has not yet reached the coil's rated maximum current, the valve core reaches its maximum displacement, forming a saturation zone. Similarly, when the valve core retracts, the valve core does not begin to move and retract until the coil current decreases to a certain value. When the coil current has not yet decreased to 0, the valve core reaches zero displacement. This hysteresis phenomenon significantly weakens the control performance of the proportional valve.

[0004] Proportional valves equipped with spool displacement sensors are also used in industrial applications. The spool displacement sensors of such proportional valves can detect spool displacement in real time, which can basically eliminate the spool displacement hysteresis problem. However, due to the above-mentioned obstruction of spool movement, there are still problems such as slow response and poor micro-motion performance.

[0005] Numerous solutions have been proposed to address these issues, including compensation methods based on the Coulomb friction model, compensation methods based on the Karnopp friction model, and dither compensation. Dither compensation is the most widely used method. This method superimposes a low-amplitude dither signal on the control signal, allowing the valve core to maintain macroscopic stationary motion while also experiencing microscopic movement. This mitigates the effects of static friction, ultimately improving the proportional valve's dynamic performance and proportional control performance while reducing hysteresis.

[0006] Through investigation, the existing research on the vibration compensation applies the vibration signal with constant frequency and amplitude to the proportional valve at different opening degrees. However, when the proportional valve is at different opening degrees, the liquid power, impact, damping and mechanical performance of the valve will change, and the force condition of the valve core will become extremely complex. For example, with the change of the displacement of the valve core, the vibration amplitude of the valve core will appear the nonlinear attenuation phenomenon. Therefore, in engineering application, different frequency and amplitude vibration signals need to be applied to the proportional valve at different opening degrees and working conditions, so as to ensure the consistency of the vibration behavior of the valve core in the stroke range. SUMMARY

[0007] In order to solve the problems in the prior art, the application provides a nonlinear vibration control method considering the high dynamic and low hysteresis and micro-motion characteristics of a proportional valve.

[0008] The technical scheme of the application is as follows:

[0009] The application first provides a nonlinear vibration control method considering the high dynamic and low hysteresis and micro-motion characteristics of a proportional valve, which comprises the following steps:

[0010] 1) Real-time detection signal of the controlled proportional valve is acquired, and mean value filtering processing is performed on the real-time detection signal to filter out the vibration signal, so as to obtain a basic detection signal;

[0011] 2) The controller acquires the current pressure difference ΔP of the controlled proportional valve, the target control signal input from outside and the real-time basic detection signal; the driving control signal is obtained according to the real-time basic detection signal and the target control signal, and the optimal vibration control signal under the current condition is obtained from the database according to the current pressure difference and the target control signal; the database pre-stores the frequency and amplitude of the optimal vibration control signal under different pressure differences ΔP of the controlled proportional valve and target control signals in the current use scene; j j

[0012] 3) The controller performs addition operation on the driving control signal and the optimal vibration control signal to obtain an equivalent control signal, and then performs PWM waveform equivalent conversion on the equivalent control signal to convert it into a control signal;

[0013] 4) The power amplifier converts the control signal into a coil voltage to directly drive the controlled proportional valve.

[0014] In the application, the detection signal of the controlled proportional valve is a current signal or a displacement signal; the detection signal is subjected to mean value filtering processing to filter out the vibration part, so as to obtain a basic detection signal;

[0015] ​​When the controlled proportional valve does not have the spool displacement detection function, the detection signal of the controlled proportional valve is the current signal, which is obtained by using the current sensor, and the basic detection signal obtained after mean filtering is the driving current without the chattering current;

[0016] When the controlled proportional valve has the spool displacement detection function, the detection signal of the controlled proportional valve is the spool displacement signal, which is obtained by using the spool displacement sensor, and the basic detection signal obtained after mean filtering is the current basic displacement of the spool without the chattering displacement.

[0017] The target control signal in step 2) is the target current or target displacement, and the type of the target control signal is the same as that of the basic detection signal. This target control signal can be a function related to the real-time running time, such as sine, cosine, square wave, and triangular wave, or a constant. The target control signal as a function of time can be directly called or directly derived and observed for its real-time value.

[0018] In step 2), the process of obtaining the driving control signal according to the real-time basic detection signal and the target control signal is to subtract the real-time basic detection signal from the target control signal, and the difference value is subjected to closed-loop control operation to obtain the driving control signal. The present application does not limit the type of closed-loop control operation, which is common knowledge in the art, for example, including but not limited to PID, LQR, MPC, neural network, ARC, etc., which can generally achieve closed-loop control of current or displacement, and are essentially a kind of correction of real-time current or real-time displacement.

[0019] Preferably, the optimal chattering control signal stored in the database corresponds to one controlled proportional valve, and the data is constructed by the following method:

[0020] 2.1) Under the current pressure difference ΔP j Next, the target control signal is input, the amplitude of the chattering signal is set to U, the control chattering frequency is gradually increased from 0, and the vibration sensor detects the chattering signal until the instant when the spool just overcomes the effect of static friction and chattering occurs. At this time, the chattering frequency is the optimal chattering control signal frequency F i ;

[0021] Subsequently, the amplitude of the chattering control signal is gradually reduced while keeping other parameters unchanged, and the vibration sensor does not detect the chattering signal until the instant when the spool cannot maintain chattering motion due to the small amplitude of the chattering voltage. The last chattering control signal amplitude before the amplitude is reduced is the optimal chattering control signal amplitude U i ; at this time, the optimal chattering control signal frequency F j and the amplitude U i of the optimal chattering control signal under the current pressure difference ΔP i , the target control signal have been determined and written into the database;

[0022] 2.2) change the target control signal with a set amplitude, and repeat step 2.1) until the target control signal reaches the maximum allowed value; thus obtaining the current pre-post valve differential pressure ΔP j optimal chatter control signal data under any given target control signal;

[0023] 2.3) again change the pre-post valve differential pressure ΔP step change the pre-post valve differential pressure ΔP j =, and repeat step 2.1) and step 2.2), until the differential pressure reaches the maximum allowed differential pressure; obtain optimal chatter control signal data under any given target control signal at any pre-post valve differential pressure; at this point, the optimal chatter control signal database of the proportional valve is established.

[0024] Compared with the prior art, the present application has the following beneficial effects:

[0025] 1. The existing proportional valve controller has little effect on hysteresis, and the chatter frequency and amplitude cannot be adjusted adaptively with the stroke of the valve core, resulting in decay of the valve core chatter amplitude and instability of the chatter movement. The control method of the present application pre-obtains optimal chatter control signals under various working conditions through experiments and builds a database, adaptively adjusts the optimal chatter control signal under the current working condition based on the database model, the frequency and amplitude thereof, and applies it to the closed-loop feedback link, which can greatly reduce hysteresis. The database model scheme bypasses the complex research on the combined mechanism of liquid dynamic force, impact force and damping force, and comprehensively measures the combined effects of the above forces to obtain the optimal chatter type, frequency and amplitude of the proportional valve under all working conditions.

[0026] 2. When the proportional valve receives a target control instruction, a larger coil current is required to overcome the static friction force greater than the dynamic friction force. When the valve core overcomes the static friction force, the friction force acting on it suddenly decreases because it changes to dynamic friction force, at this time the coil current is still at a high level, and the valve core will produce a great acceleration, causing displacement overshoot. Under the nonlinear chatter control method proposed in the present application, the valve core will always be in a macroscopically stable and microscopically dithering state, so the speed of responding to the control signal is faster, the dead zone and saturation zone range of the proportional valve current-displacement curve will be reduced, the linearity is higher, and the micro-motion performance is better.

[0027] 3. The nonlinear chatter control method proposed in the present application is used for all electromagnetic proportional slide valves. It can output optimal chatter control signals to adapt to proportional valves of different structures, thereby achieving the most ideal chatter effect.

[0028] 4. The integral of the chatter control signal proposed in the present application in the time domain is 0, so its equivalent value is 0, and theoretically it does not consume additional energy of the system.

[0029] 5. The mean value filtering operation frequency and the tremor signal frequency are real-time synchronized, so that the filtered signal will not be distorted with the change of the tremor frequency. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 for ideal current-displacement curve (no hysteresis);

[0031] Figure 2 for actual current-displacement curve (with hysteresis);

[0032] Figure 3 for two-position two-way electromagnetic proportional valve structure schematic diagram;

[0033] Figure 4 for nonlinear tremor control principle diagram;

[0034] Figure 5 for the superposition operation of the driving control signal and the tremor signal in the controller;

[0035] Figure 6 for the valve core tremor movement schematic diagram;

[0036] Figure 7 for the best tremor type, frequency, amplitude database construction process schematic diagram;

[0037] Figure 8 for experimental current-displacement curve (no tremor) schematic diagram;

[0038] Figure 9 for experimental current-displacement curve (with tremor) schematic diagram. DETAILED DESCRIPTION

[0039] The present application will be further described and illustrated below in conjunction with specific embodiments. The embodiments are only exemplary and do not circumscribe the scope of the present disclosure. The technical features of each embodiment of the present application can be combined accordingly without conflict.

[0040] The application object of the nonlinear tremor control method of the present application, which takes into account the high dynamic and low hysteresis of the proportional valve and the micro-motion characteristics, includes all proportional slide valves. The following examples take a two-position two-way electromagnetic proportional valve as an example for illustration. The present application establishes a valve core displacement coordinate system, with the horizontal coordinate being the axial valve core displacement (positive to the right) and the vertical coordinate being the radial valve core displacement (positive upward), as shown in Figure 3 The valve core displacement coordinate system in the figure is relatively static with the valve body and is fixed. When the electromagnetic coil is not powered, the valve core position in the figure is defined as the valve core displacement origin, and the piston blocks the oil liquid of the inlet port from the outlet port; when the electromagnetic coil is powered, the armature is moved to the right under the action of the electromagnetic force of the coil, and the piston and the outlet port have a gap, and the inlet port and the outlet port are connected.

[0041] Take the electromagnetic proportional valve without spool displacement detection function as an example. For such a controlled proportional valve, the current sensor is used to obtain the current signal of the valve coil as the detection signal, and the target control signal is also the detection signal. As shown in the figure, the principle of the nonlinear chattering control system of such an electromagnetic proportional valve mainly includes: current sensor, mean filter module, controller and power amplifier. Among them, the current sensor is used to obtain the current signal of the proportional valve, the mean filter module processes the current signal to obtain the real-time driving current, the controller is used to output the equivalent control signal containing the driving control signal and the chattering control signal, and the equivalent control signal is subjected to PWM waveform equivalent conversion; the power amplifier converts the control signal into coil voltage to drive the proportional valve.

[0042] If the controlled proportional valve has a spool displacement detection function (i.e. has a spool displacement sensor), the spool displacement signal can be directly used as the detection signal, and the target control signal is the displacement signal. Figure 4 The corresponding current sensor is replaced by a displacement sensor, and the spool displacement signal is filtered to filter out the chattering displacement to obtain the basic displacement of the spool.

[0043] The working principle of the system of the application is:

[0044] 1) Real-time acquisition of the detection signal of the controlled proportional valve, filtering of the real-time detection signal to filter out the chattering signal, and obtaining of the basic detection signal;

[0045] 2) The controller acquires the current pressure difference ΔP j of the controlled proportional valve before and after the valve, the target control signal input from the outside and the real-time basic detection signal; the driving control signal is obtained according to the real-time basic detection signal and the target control signal, and the optimal chattering control signal under the current condition is obtained from the database according to the current pressure difference before and after the valve and the target control signal; the database has pre-stored the frequency and amplitude of the optimal chattering control signal under different pressure differences ΔP j of the controlled proportional valve before and after the valve and the target control signal in the current use scene;

[0046] 3) The controller adds the driving control signal and the optimal chattering control signal to obtain the equivalent control signal, and then converts the equivalent control signal into a control signal through PWM waveform equivalent conversion;

[0047] 4) The power amplifier converts the control signal into coil voltage to directly drive the controlled proportional valve.

[0048] As Figure 5As shown, the waveform of the chatter control signal can be a square wave, a left vertical line triangle wave, a right vertical line triangle wave, a sawtooth wave, a sine wave, and the like. However, for the same use scenario (the same load), the optimal waveform of the chatter control signal is determined and does not need to be changed. Therefore, before the database of the present application is constructed, the waveform of the chatter control signal under the use scenario has been determined based on the prior art, and the present application does not need to study the waveform when the database is constructed, and the constructed chatter signal is of the same waveform. In different use scenarios, the most suitable chatter waveform can be used according to the actual situation to achieve the best hysteresis improvement effect, but the database needs to be reconstructed. Since the integral of the chatter control signal in the time domain is 0, the equivalent value is 0, and theoretically no additional energy is consumed by the system.

[0049] To facilitate a detailed explanation of the present application, an electromagnetic proportional valve without spool displacement detection function (both the detection signal and the control signal are current signals) is taken as an example to describe the control method of the present application in detail. Under the excitation of the coil voltage, the electromagnetic coil current is superimposed by two parts: the driving current I0 and the chatter current I chatter . As shown, under the action of the driving current I0, the spool generates a basic displacement x0, and under the action of the chatter current I chatter , the spool generates a chatter displacement x chatter with an amplitude A centered on the displacement x0. In the control system of the present application, the coil current fed back to the controller must eliminate the chatter part to ensure the closed-loop stability of the basic displacement x0. In this embodiment, the elimination of the chatter part is realized by a mean filter, and the coil current signal input to the controller after filtering only contains the driving current I0 signal and does not contain the chatter current I chatter signal. In addition, the mean filtering operation frequency F filter is real-time synchronized with the current chatter signal frequency, i.e. F filter =F, so as to ensure that the filtered signal will not be distorted with the change of the chatter frequency. Although the filtering link will cause a certain lag of the signal, the closed-loop operation frequency of most controllers on the market is much greater than the chatter frequency of the spool, and this lag is not enough to affect the control performance of the electromagnetic proportional valve.

[0050] The equivalent control signal PWM waveform equivalent conversion rule is as follows: in the process of converting the equivalent control signal into a control signal, the controller samples the equivalent control signal at a certain sampling frequency F sample . Assuming that the sampling is performed at time t, the instantaneous value E(t) is obtained. Subsequently, the sampled instantaneous value E(t) is normalized to the range [0, 1], and the equivalent duty ratio of the control signal is calculated:

[0051]

[0052] E maxis the maximum value of the equivalent control signal, U is the amplitude of the dither control signal, and E is the drive control signal.

[0053] The PWM frequency of the control signal is usually tens to hundreds of times the dither frequency. Therefore, the control signal after the equivalent control signal is equivalently converted from the PWM waveform can well fit the equivalent control signal.

[0054] The optimal frequency and amplitude of the nonlinear dither signal output by the control system of the present invention are obtained by searching a database that pre-stores the optimal frequencies and amplitudes of nonlinear dither signals under different operating conditions. The present invention does not limit the method for obtaining the optimal nonlinear dither signal; these optimal parameters can be obtained through various approaches, including mathematical modeling and experimental measurement.

[0055] This embodiment of the present invention uses a partial mathematical modeling and full-operation experimental measurements as examples to provide a detailed description of the optimal nonlinear dither signal acquisition method. It should be noted that the optimal nonlinear dither signal acquisition method proposed in this embodiment of the present invention is applicable to all proportional spool valves. Previous research has shown that the dither frequency and amplitude parameters of proportional valve spools have optimal ranges, which are determined by the structural parameters of the proportional valve.

[0056] The testing principle of the optimal chatter signal database is as follows Figure 7 As shown. At the current pressure difference before and after the valve ΔP j Next (where And is an integer, ΔP max is the maximum pressure difference before and after the valve, ΔP step To test the pressure difference step before and after the valve, ΔP j The system input is the target signal that increases in a certain step size. Taking the current signal as the target signal as an example, the system input is the target signal that increases in a certain step size. step Increased target current I i ,in And is an integer, I max It is the maximum rated current of the proportional valve solenoid coil.

[0057] For proportional valves without spool displacement detection, the coil current includes a flutter component even when the valve core is not in a flutter state. Therefore, the flutter state of the valve core cannot be determined based on the coil current. To address this, the present invention employs an additional vibration sensor to determine the critical flutter state of the valve core. Specifically, the vibration sensor detects the flutter signal waveform and then determines the flutter state based on the waveform characteristics. For proportional valves with spool displacement detection, the displacement waveform obtained by the spool displacement sensor can be directly used to determine the flutter state.

[0058] The optimal chatter control signal stored in the database of the application corresponds to the controlled proportional valve one by one, and the data is constructed by the following method:

[0059] 2.1) Install a vibration sensor for detecting the chatter signal for the controlled proportional valve (the controlled proportional valve has a valve core displacement detection function, and the chatter signal can be directly detected by the valve core displacement sensor), the vibration sensor only needs to be able to detect the chatter signal, the chatter signal is a regular periodic function, and the period and amplitude can be judged from the signal, so as to obtain the chatter frequency and amplitude (whether the vibration is started); under the current pre-valve / post-valve pressure difference ΔP j , input the target current I i (For proportional valves with valve core displacement detection function, input the target displacement x i ), the amplitude of the chatter signal is set as U, the control chatter frequency is gradually increased from 0, until the vibration sensor detects the chatter signal, at this moment the valve core just overcomes the effect of static friction and occurs chatter, and the frequency F i of the optimal chatter control signal is determined; then keep the current other parameters unchanged, gradually reduce the amplitude of the chatter control signal, until the vibration sensor cannot detect the chatter signal, at this moment the valve core just cannot maintain the chatter movement due to the too small amplitude of the chatter voltage, and the last chatter control signal amplitude before the amplitude is reduced is the current optimal chatter control signal amplitude U i ; at this time, under the current pre-valve / post-valve pressure difference ΔP j , the frequency F i and the amplitude U i of the optimal chatter control signal under the target current I i (or target displacement x i ) have been determined and written into the database;

[0060] 2.2) Change the given target current I i ' = I i + I step (or target displacement x i ' = x i + x step ), repeat step 2.1), until the optimal chatter control signal data under any given target current (target displacement) under the current pre-valve / post-valve pressure difference ΔP j is obtained;

[0061] 2.3) Change the pre-valve / post-valve pressure difference ΔP j , ΔP j ' = ΔP j + ΔP step , and repeat steps 2.1) and 2.2), until The optimal dither control signal data under any pre-valve / post-valve pressure difference and any target current (or target displacement) are obtained; thus, the optimal dither control signal database of the proportional valve is established.

[0062] After the database is established, enter the required current valve front / valve back pressure difference ΔP j The optimal flutter frequency and amplitude required by the proportional valve can be obtained by using the given target current (or target displacement). The experimental results of the nonlinear flutter control method proposed in this invention are as follows: Figure 9 As shown in the figure, the red curve represents the extension of the valve core, and the blue curve represents the retraction of the valve core. Figure 8 The chatter-free results show significantly reduced hysteresis and improved current-displacement linearity. Under the control method of this invention, the valve core remains macroscopically stable with microscopic dithering, resulting in a faster response to control signals. The dead zone and saturation zone of the proportional valve's current-displacement curve are reduced, resulting in improved linearity.

[0063] The above-described embodiments merely illustrate several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. Persons skilled in the art will readily appreciate that variations and modifications may be made without departing from the scope of the present invention, all of which fall within the scope of protection of the present invention.

Claims

1. A nonlinear flutter control method that takes into account the high dynamic, low hysteresis and micro-motion characteristics of a proportional valve, characterized by: The steps include: 1) Acquire the detection signal of the controlled proportional valve in real time, perform mean filtering on the real-time detection signal to filter out the chatter signal, and obtain the basic detection signal; 2) The controller obtains the current pressure difference ΔP before and after the controlled proportional valve j , external input target control signal and real-time basic detection signal; The drive control signal is obtained based on the real-time basic detection signal and the target control signal, and the optimal vibration control signal under the current conditions is obtained from the database based on the current valve front-to-back pressure difference and the target control signal; the database pre-stores the different valve front-to-back pressure differences ΔP of the controlled proportional valve in the current usage scenario. j , the frequency and amplitude of the optimal flutter control signal under the target control signal; The optimal vibration control signals stored in the database correspond one-to-one to the controlled proportional valves, and the database is constructed by the following method: 2.1) Pressure difference ΔP before and after the current valve j Under the condition of φ 1, input the target control signal, set the dither signal amplitude to U, and control the dither frequency to gradually increase from 0 until the vibration sensor detects the dither signal. At this moment, the valve core just overcomes the static friction and dithers. The dither frequency at this moment is the optimal dither control signal frequency F. i ; Then, keep the other current parameters unchanged and gradually reduce the amplitude of the dither control signal until the vibration sensor can no longer detect the dither signal. At this moment, the valve core is unable to maintain the dither motion because the amplitude of the dither voltage is too small. The amplitude of the previous dither control signal before the amplitude is reduced is the optimal dither control signal U. i Amplitude; So far, the pressure difference before and after the current valve is ΔP j , the optimal vibration control signal frequency F under the target control signal i and amplitude U i Determined and written to the database; 2.2) Change the target control signal with the set amplitude and repeat step 2.1) until the target control signal reaches the maximum allowable value; thereby obtaining the current pressure difference ΔP before and after the valve j Optimal vibration control signal data under any given target control signal; 2.3) Then increase the pressure difference by the set value ΔP step Change the pressure difference ΔP before and after the valve j =, and repeat steps 2.1) and 2.2) until the pressure difference reaches the maximum allowable pressure difference; obtain the optimal dither control signal data under the pressure difference before and after any valve and any given target control signal; at this point, the optimal dither control signal database for the proportional valve is established; 3) The controller adds the drive control signal and the optimal dither control signal to obtain an equivalent control signal, and then performs a PWM waveform equivalent conversion on the equivalent control signal to convert it into a control signal; The equivalent control signal is converted into a PWM waveform equivalently, specifically: The controller uses the set sampling frequency F sample The equivalent control signal is sampled; assuming that the sampling is performed at time t, the instantaneous value is E(t); then the sampled instantaneous value E(t) is normalized to the range of [0,1], and the equivalent duty cycle of the control signal is calculated: Among them, E max is the maximum value of the equivalent control signal, U is the amplitude of the dither control signal, and E is the drive control signal; The controller can generate a control signal according to the equivalent duty cycle; 4) The power amplifier converts the control signal into coil voltage to directly drive the controlled proportional valve.

2. The control method according to claim 1, characterized in that: In step 1), the detection signal of the controlled proportional valve is a current signal or a displacement signal; the detection signal is subjected to mean filtering to filter out the chattering part to obtain a basic detection signal; When the controlled proportional valve does not have a valve core displacement detection function, the detection signal of the controlled proportional valve is a current signal, which is obtained by a current sensor, and the basic detection signal obtained after mean filtering is a driving current without a chatter current; When the controlled proportional valve has a valve core displacement detection function, the detection signal of the controlled proportional valve is a valve core displacement signal, which is obtained by a valve core displacement sensor. The basic detection signal obtained after mean filtering is the current basic displacement of the valve core excluding the flutter displacement.

3. The control method according to claim 2, characterized in that: The operation frequency F of the mean filter filter Synchronize with the current vibration signal frequency F in real time, that is, F filter =F to ensure that the filtered signal will not be distorted as the frequency of the vibration signal changes.

4. The control method according to claim 1, wherein: In step 2), the pressure difference before and after the valve is ΔP j Obtained through a pressure sensor; the external input target control signal is a target current or a target displacement, and the type of the target control signal is the same as the type of the basic detection signal.

5. The control method according to claim 1, characterized in that: In step 2), the process of obtaining the drive control signal based on the real-time basic detection signal and the target control signal is: the real-time basic detection signal and the target control signal are subtracted, and the difference is subjected to current closed-loop control or displacement closed-loop operation to obtain the drive control signal.

6. The control method according to claim 1, characterized in that: The dither type of the optimal dither control signal is pre-set according to the usage scenario of the controlled proportional valve. Once the usage scenario is determined, the dither type is determined. The dither type does not change with the pressure difference ΔP before and after the valve. j and target control signals.

7. The control method according to claim 1, characterized in that: When the controlled proportional valve does not have a valve core displacement detection function, a vibration sensor for detecting a chatter signal is installed on the controlled proportional valve. The target control signal is a target current. The target current is initially set to the minimum allowable value and is gradually increased in step 2.2). When the controlled proportional valve has a valve core displacement detection function, a built-in valve core displacement sensor is used to obtain a chatter signal, or a vibration sensor is installed on the controlled proportional valve to obtain a chatter signal. The target control signal is the valve core target displacement. The valve core target displacement is initially selected to the minimum allowable value and is gradually increased in step 2.2).

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