A solenoid valve chatter signal injection control method and system

Abstract

This invention proposes a method and system for injecting and controlling chatter disturbance signals into an electromagnetic valve, specifically relating to the field of hydraulic control technology. First, the injection frequency of the user's chatter disturbance signal and the controller's cutoff frequency are obtained. Then, an injection module is selected based on these two frequencies. If the injection frequency is lower than the controller's cutoff frequency, a low-frequency injection module is selected; otherwise, a high-frequency injection module is selected. The low-frequency injection module generates a PWM duty cycle signal to drive the first electromagnetic valve, or the high-frequency injection module generates a PWM duty cycle signal to drive the second electromagnetic valve. This invention can inject chatter disturbance signals of specific frequencies according to user requirements, satisfying the user's desired chatter injection strategy and ensuring a wide frequency injection range for the system. This overcomes the influence of hydraulic viscosity on the system's rapid adjustment, assisting field engineers in achieving efficient automated project debugging.

Description

Technical Field

[0001] This invention relates to the technical field of hydraulic control, and more specifically, to a method and system for controlling the injection of electromagnetic valve chatter signals. Background Technology

[0002] A solenoid valve is a device that converts electrical energy into mechanical energy. Commonly used in fluid control, it is a fundamental component of automation systems used to control fluids and belongs to the actuator category. In many applications, precise control of solenoid valves is required. Pulse Width Modulation (PWM) is a technique that controls the output power of electrical equipment by changing the pulse width or duty cycle. PWM control can be used to adjust the on / off time of the solenoid valve.

[0003] In most hydraulic control applications, to prevent the solenoid valve from developing significant viscous forces when the set opening remains unchanged for extended periods, hindering subsequent adjustments, a certain amount of chatter disturbance needs to be injected near the set opening. A common approach is to inject the chatter disturbance signal into the reference current signal and use PWM closed-loop control to make the solenoid valve current track the reference signal. However, this method involves a filtering stage in the acquisition circuit, preventing the observation of high-frequency signals in the feedback current, thus failing to meet the requirement for high-frequency chatter signal injection. In some control system applications, the system needs to incorporate chatter at a specific frequency according to user-defined requirements. However, the capacitor filtering stage introduced in the acquisition circuit design prevents the acquisition of higher-frequency current changes, causing high-frequency chatter injection to fail. Therefore, designing a chatter injection strategy that meets user requirements and assists field engineers in achieving efficient automated project debugging is a pressing technical problem that needs to be solved. Summary of the Invention

[0004] To address the problems mentioned in the background section, this invention proposes a solenoid valve chatter disturbance signal injection strategy and system. This invention can inject chatter disturbance signals of a specific frequency according to user needs, satisfying the chatter injection strategy required by the user and ensuring that the system has a wide frequency injection range. This overcomes the influence of hydraulic viscosity on the rapid adjustment of the system and assists field engineers in achieving efficient automated project debugging.

[0005] To achieve the above-mentioned technical effects, the technical solution of the present invention is as follows:

[0006] A method for injecting and controlling electromagnetic valve chatter disturbance signals includes the following steps:

[0007] S1. Obtain the injection frequency and controller cutoff frequency of the user's flutter disturbance signal;

[0008] S2. Based on the injection frequency of the flutter disturbance signal and the controller cutoff frequency, select an injection module. If the injection frequency is lower than the controller cutoff frequency, select a low-frequency injection module and proceed to step S3; otherwise, select a high-frequency injection module and proceed to step S4.

[0009] S3. A PWM duty cycle signal is generated by a low-frequency injection module to drive the solenoid valve;

[0010] S4. A PWM duty cycle signal is generated using a high-frequency injection module to drive the solenoid valve.

[0011] This technical solution addresses the problem of designing a chatter injection strategy that meets user requirements and assists field engineers in achieving efficient automated project debugging. The invention studies a switching control strategy. First, it obtains the injection frequency of the user's chatter disturbance signal and the controller's cutoff frequency. Then, based on these frequencies, it selects either a low-frequency or high-frequency injection module. Finally, it uses the low-frequency or high-frequency injection module to generate a PWM duty cycle signal to drive the solenoid valve. This switching control strategy for chatter disturbance signal injection can inject chatter disturbance signals of a specific frequency according to user needs, satisfying the user's chatter injection requirements. Furthermore, the chatter frequency of the injected chatter disturbance signal is not affected by circuit parameter design, not only meeting the requirements of the field operating conditions but also ensuring a wide frequency injection range for the system. This overcomes the influence of hydraulic viscosity on the system's rapid adjustment, assisting field engineers in achieving efficient automated project debugging.

[0012] Preferably, the low-frequency injection module is provided with a signal terminal for receiving reference current signals and low-frequency flutter disturbance signals, a controller, a solenoid valve, and a data acquisition circuit. The signal terminal is connected to the input terminal of the controller, the output terminal of the controller is connected to the input terminal of the solenoid valve, the output terminal of the solenoid valve is connected to the input terminal of the data acquisition circuit, and the output terminal of the data acquisition circuit is connected back to the signal terminal, forming a control loop.

[0013] Preferably, S1 also acquires the amplitude of the user flutter disturbance signal. In the low-frequency injection module, a sinusoidal disturbance signal is generated based on the injection frequency and amplitude of the user flutter disturbance signal. This signal is then superimposed on the signal terminal of the control loop of the low-frequency injection module along with the desired current as the overall desired reference signal.

[0014] Preferably, the process of using a low-frequency injection module to generate a PWM duty cycle signal to drive the solenoid valve is as follows:

[0015] S31. The signal terminal in the low-frequency injection module receives the input reference current signal and the low-frequency flutter disturbance signal;

[0016] S32. At the signal terminal, the input reference current signal and low-frequency flutter disturbance signal are subtracted from the feedback current signal of the solenoid valve to obtain the difference value. The difference value is used as the input signal of the controller, and the controller outputs the PWM duty cycle signal to the input terminal of the solenoid valve.

[0017] S33. The acquisition circuit acquires the current signal output by the solenoid valve, and injects the output feedback current into the signal terminal. The signal terminal transmits the reference current signal, feedback current and low-frequency flutter signal back to the controller to complete the closed-loop drive control of the low-frequency injection module.

[0018] Preferably, the high-frequency injection module includes a signal terminal for receiving a reference current signal, a controller, an injection terminal for injecting high-frequency flutter disturbance signals, a solenoid valve, a data acquisition circuit, and a notch filter. The signal terminal is connected to the input terminal of the controller, the output terminal of the controller is connected to the injection terminal, the injection terminal is connected to the input terminal of the solenoid valve, the output terminal of the solenoid valve is connected to the input terminal of the data acquisition circuit, the output terminal of the data acquisition circuit is connected to the input terminal of the notch filter, and the output terminal of the notch filter is connected back to the signal terminal, forming a control loop.

[0019] Preferably, the process of using a high-frequency injection module to generate a PWM duty cycle signal to drive the solenoid valve is as follows:

[0020] S41. The signal terminal in the high-frequency injection module receives the input reference current signal, calculates the difference between it and the output signal of the notch filter, and uses the difference as the input of the controller.

[0021] S42. The controller outputs a drive signal PWM1, sets the duty cycle signal equivalent to the high-frequency jitter disturbance signal to PWM2, adds the two signals at the injection terminal, and outputs them to the input terminal of the solenoid valve.

[0022] S43. The acquisition circuit acquires the current signal output by the solenoid valve and outputs it to the notch filter;

[0023] S44. The notch filter filters the received current signal and outputs a feedback current that is injected into the signal terminal. The signal terminal then transmits the reference current signal and the feedback current to the controller to complete the closed-loop drive control of the high-frequency injection module.

[0024] Preferably, the notch filter filters the received current signal Is, and the specific filtering calculation formula is as follows:

[0025] W(k)=Is(k)+2*r*cos(ω0)*W(k-1)-r*r*W(k-2)

[0026]

[0027] Where k represents the current control cycle, W(k) represents the intermediate variable data of the notch filter in the k-th control cycle, Is(k) represents the current signal acquired by the acquisition circuit in the k-th control cycle, r represents the notch constant, and ω0 represents the digital frequency of the notch filter, ω0=2πf d / f s f d f represents the flutter frequency of the flutter disturbance signal. s Let W(k-1) represent the sampling frequency of the closed-loop control, W(k-1) represent the intermediate variable data of the notch filter in the (k-1)th control cycle, and W(k-2) represent the intermediate variable data of the notch filter in the (k-2)th control cycle. This represents the feedback current output by the notch filter.

[0028] Preferably, the controller performs calculations on the input signal, and the specific processing procedure is as follows:

[0029] S451. Based on the reference current signal and the feedback current, calculate the current error signal. The specific calculation expression is as follows:

[0030]

[0031] Where err(k) represents the current error signal of the kth control cycle, and I_ref(k) represents the reference current signal of the kth control cycle;

[0032] S452. Based on the current error signal, calculate the control quantity y of the controller. The specific calculation expression is as follows:

[0033]

[0034] Where y(k) represents the intermediate variable of the controller in the k-th control cycle, K p K represents the proportional parameter of the controller. i The integral parameters of the controller are represented, j = 1, 2, 3, ..., k, and err(j) represents the cumulative value of the error current signal from the j-th control cycle to the k-th control cycle.

[0035] S453. Based on the intermediate variable y(k) of the controller, calculate the PWM duty cycle. The specific calculation expression is as follows:

[0036]

[0037] Where U(k) represents the PWM duty cycle of the control circuit output, Udc represents the bus voltage, and U d (k) represents the PWM duty cycle equivalent to the jitter disturbance signal in the kth control cycle.

[0038] Preferably, the reference current signal is the current signal output by the outer loop displacement controller.

[0039] This invention also proposes a control system for injecting electromagnetic valve chatter disturbance signals, the system comprising:

[0040] The acquisition module is used to acquire the injection frequency and controller cutoff frequency of the user's flutter disturbance signal;

[0041] The selection module is used to select an injection module based on the injection frequency of the flutter disturbance signal and the controller cutoff frequency. If the injection frequency is lower than the controller cutoff frequency, the injection module is selected as a low-frequency injection module; otherwise, the injection module is selected as a high-frequency injection module.

[0042] The first drive module is used to drive the solenoid valve by generating a PWM duty cycle signal using a low-frequency injection module.

[0043] The second drive module is used to drive the solenoid valve by generating a PWM duty cycle signal using a high-frequency injection module.

[0044] Compared with the prior art, the beneficial effects of the technical solution of the present invention are:

[0045] This invention proposes a method and system for controlling the injection of a solenoid valve chatter signal. The invention investigates a switching control strategy. First, the injection frequency of the user's chatter disturbance signal and the controller's cutoff frequency are obtained. Then, based on the injection frequency and controller cutoff frequency, an injection module is selected as either a low-frequency or high-frequency injection module. The low-frequency or high-frequency injection module then generates a PWM duty cycle signal to drive the solenoid valve. This switching control strategy for chatter disturbance signal injection can inject chatter disturbance signals of a specific frequency according to user needs, satisfying the user's required chatter injection strategy. Moreover, the chatter frequency of the injected chatter disturbance signal is not affected by the circuit parameter design, not only meeting the requirements of the field working conditions but also ensuring a wide frequency injection range for the system. This overcomes the influence of hydraulic viscosity on the system's rapid adjustment, assisting field engineers in achieving efficient automated project debugging. Attached Figure Description

[0046] Figure 1 This is a flowchart illustrating a method for injecting and controlling electromagnetic valve chatter disturbance signals according to an embodiment of the present invention.

[0047] Figure 2 This diagram illustrates the structural connection of the low-frequency injection module proposed in this embodiment of the invention.

[0048] Figure 3 This diagram shows the waveform of the low-frequency injection module for injecting low-flutter disturbance signals according to the embodiments of the present invention.

[0049] Figure 4 This diagram shows the waveform of the high-flutter disturbance signal injection low-frequency injection module proposed in this embodiment of the invention.

[0050] Figure 5 This diagram illustrates the structural connection of the high-frequency injection module proposed in this embodiment of the invention.

[0051] Figure 6 This diagram shows the waveform of the high-frequency injection module for injecting high-flutter disturbance signals according to an embodiment of the present invention.

[0052] Figure 7 This diagram shows the modulation result of the PWM duty cycle signal proposed in the embodiments of the present invention.

[0053] Figure 8 This diagram illustrates the structure of a solenoid valve chatter disturbance signal injection control system proposed in this embodiment of the invention. Detailed Implementation

[0054] The accompanying drawings are for illustrative purposes only and should not be construed as limiting the invention.

[0055] To better illustrate this embodiment, some parts of the accompanying drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions;

[0056] It is understandable to those skilled in the art that some well-known details may be omitted from the accompanying drawings.

[0057] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0058] The positional relationships depicted in the accompanying drawings are for illustrative purposes only and should not be construed as limiting the invention.

[0059] Example 1

[0060] like Figure 1 As shown, this embodiment proposes a method for controlling the injection of electromagnetic valve chatter signals, including the following steps:

[0061] S1. Acquire user flutter disturbance signal I d Injection frequency f d and controller cutoff frequency f B ;

[0062] In step S1, the amplitude A of the user flutter disturbance signal is also acquired. d And set the controller's sampling frequency to f s The bus voltage is U dc The process of obtaining parameter data in this step is the initialization process of the injection module.

[0063] S2. According to the flutter disturbance signal Id Injection frequency f d and controller cutoff frequency f B Select the injection module, if the injection frequency f d Below the controller cutoff frequency f B If the condition is met, select the low-frequency injection module and proceed to step S3; otherwise, select the high-frequency injection module and proceed to step S4.

[0064] In step S2, when selecting the injection module, if the injection frequency f d Below the controller cutoff frequency f B The specific expression is as follows:

[0065] f d <f B

[0066] Then select the low-frequency injection module; otherwise, the injection frequency f d Greater than or equal to the controller cutoff frequency f B Select the high-frequency injection module as the injection module;

[0067] See Figure 2 The low-frequency injection module in step S2 is equipped with a signal terminal, a controller, a solenoid valve, and a data acquisition circuit for receiving reference current signals and low-frequency flutter disturbance signals. The signal terminal is connected to the input terminal of the controller, the output terminal of the controller is connected to the input terminal of the solenoid valve, the output terminal of the solenoid valve is connected to the input terminal of the data acquisition circuit, and the output terminal of the data acquisition circuit is connected back to the signal terminal, forming a control loop. In the low-frequency injection module, a sinusoidal disturbance signal is generated according to the injection frequency and amplitude of the user's flutter disturbance signal, and is superimposed on the signal terminal of the control loop of the low-frequency injection module together with the desired current as the total desired reference signal.

[0068] S3. A PWM duty cycle signal is generated by a low-frequency injection module to drive the solenoid valve;

[0069] In step S3, the PWM duty cycle signal refers to the ratio of the high-level time to the period time of the jitter disturbance signal. The specific execution process of generating the PWM duty cycle signal to drive the solenoid valve using the low-frequency injection module is as follows:

[0070] S31. The signal terminal in the low-frequency injection module receives the input reference current signal and the low-frequency flutter disturbance signal;

[0071] In step S31, the reference current signal is the current signal output by the outer loop displacement controller.

[0072] S32. Input the reference current signal I_ at the signal terminal. ref and low-frequency flutter disturbance signal I dThe difference is calculated by subtracting the feedback current signal from the solenoid valve. This difference is then used as the input signal for the controller, which outputs a PWM duty cycle signal to the input terminal of the solenoid valve.

[0073] S33. The acquisition circuit acquires the current signal output by the solenoid valve and outputs a feedback current I. f Feedback is injected into the signal terminal, and the signal terminal will input the reference current signal I_ ref Feedback current I f and low-frequency flutter signal I d The data is transmitted back to the controller to complete the closed-loop drive control of the low-frequency injection module.

[0074] However, a low-frequency flutter signal I is injected into the low-frequency injection module. d During the process, this process can only convert low-frequency flutter signals I d The low-frequency injection module cannot inject high-frequency flutter signals because there is a filtering stage in the acquisition circuit of the low-frequency injection module, which causes the feedback current I... f High-frequency signals could not be observed; see Figure 3 In the low-frequency injection module, the y-axis represents the injected dizziness signal, and the x-axis represents the time period. Figure 3 The curve in the image shows obvious fluctuations, indicating that the low-frequency flutter disturbance signal was successfully injected into the low-frequency injection module; see [link / reference]. Figure 4 , Figure 4 The curve in the middle tends to be a smooth curve, indicating that the injection of high-frequency flutter disturbance signal into the low-frequency injection module has failed.

[0075] S4. A PWM duty cycle signal is generated using a high-frequency injection module to drive the solenoid valve.

[0076] In this embodiment, a switching control strategy is studied. First, the injection frequency and controller cutoff frequency of the user's flutter disturbance signal are obtained. Then, based on the injection frequency and controller cutoff frequency, the injection module is selected as a low-frequency injection module or a high-frequency injection module. The low-frequency injection module or the high-frequency injection module is then used to generate a PWM duty cycle signal to drive the solenoid valve. The flutter disturbance signal injection switching control strategy of this invention can inject a flutter disturbance signal of a specific frequency according to user needs, satisfying the user's required flutter injection strategy. Moreover, the flutter frequency of the injected flutter disturbance signal is not affected by the circuit parameter design. It not only meets the requirements of the field working conditions, but also ensures that the system has a wide frequency injection range, thereby overcoming the influence of hydraulic viscosity on the rapid adjustment of the system and assisting field engineers in achieving efficient automated project debugging.

[0077] Example 2

[0078] This embodiment further explains the high-frequency injection module; see [link to documentation]. Figure 5The high-frequency injection module is equipped with a function to receive a reference current signal I_ ref Signal terminals, controllers, and signals used for high-frequency flutter disturbance signals I d The system includes an injection terminal, a solenoid valve, a data acquisition circuit, and a notch filter. The signal terminal is connected to the input terminal of a controller, the output terminal of the controller is connected to the injection terminal, the injection terminal is connected to the input terminal of the solenoid valve, the output terminal of the solenoid valve is connected to the input terminal of the data acquisition circuit, the output terminal of the data acquisition circuit is connected to the input terminal of the notch filter, and the output terminal of the notch filter is connected back to the signal terminal, forming a control loop.

[0079] Step S3, which involves generating a PWM duty cycle signal using a high-frequency injection module to drive the solenoid valve, is executed as follows:

[0080] S41. The signal terminal in the high-frequency injection module receives the input reference current signal I_ ref The difference is calculated by subtracting the output signal from the notch filter, and the difference is used as the input to the controller.

[0081] S42. The controller outputs drive signal PWM1 to set the high-frequency jitter disturbance signal I. d The equivalent duty cycle signal is PWM2. After the two are added together at the injection terminal, the result is output to the input terminal of the solenoid valve.

[0082] S43. The acquisition circuit acquires the current signal Is output by the solenoid valve and outputs it to the notch filter;

[0083] S44. The notch filter filters the received current signal Is and outputs a feedback current I. f Feedback is injected into the signal terminal, and the signal terminal will input the reference current signal I_ ref and feedback current I f The data is transmitted to the controller to complete the closed-loop drive control of the high-frequency injection module.

[0084] In step S44, the notch filter filters the received current signal Is, and the specific filtering calculation formula is as follows:

[0085] W(k)=Is(k)+2*r*cos(ω0)*W(k-1)-r*r*W(k-2)

[0086]

[0087] Where k represents the current control cycle, W(k) represents the intermediate variable data of the notch filter in the k-th control cycle, Is(k) represents the current signal acquired by the acquisition circuit in the k-th control cycle, r represents the notch constant, and ω0 represents the digital frequency of the notch filter, ω0=2πf d / f s f d f represents the flutter frequency of the flutter disturbance signal.s Let W(k-1) represent the sampling frequency of the closed-loop control, W(k-1) represent the intermediate variable data of the notch filter in the (k-1)th control cycle, and W(k-2) represent the intermediate variable data of the notch filter in the (k-2)th control cycle. This represents the feedback current output by the notch filter.

[0088] The controller processes the input signal and records the output signal of the notch filter. For feedback current I f The specific processing procedure is as follows:

[0089] S451. Based on reference current signal I _ref and feedback current I f The current error signal is calculated using the following expression:

[0090]

[0091] Where err(k) represents the current error signal of the kth control cycle, and I_ref(k) represents the reference current signal of the kth control cycle;

[0092] S452. Based on the current error signal, calculate the control quantity y of the controller. The specific calculation expression is as follows:

[0093]

[0094] Where y(k) represents the intermediate variable of the controller in the k-th control cycle, K p K represents the proportional parameter of the controller. i The integral parameters of the controller are represented, j = 1, 2, 3, ..., k, err(j) represents the cumulative value of the error current signal from the j-th control cycle to the k-th control cycle; when the flutter disturbance signal enters the next control cycle, let k = k + 1, and return to step S44;

[0095] S453. Based on the intermediate variable y(k) of the controller, calculate the PWM duty cycle. The specific calculation expression is as follows:

[0096]

[0097] Where U(k) represents the PWM duty cycle of the control circuit output, Udc represents the bus voltage, and U d (k) represents the PWM duty cycle equivalent to the jitter disturbance signal in the kth control cycle.

[0098] In this embodiment, when a high-frequency flutter disturbance signal is injected into the high-frequency injection module, the high-frequency injection module generates a PWM duty cycle signal to drive the solenoid valve according to the closed-loop control circuit of the injected high-frequency flutter disturbance signal; such as Figure 6 As shown, in the high-frequency injection module, the y-axis represents the injected dizziness signal, and the x-axis represents the time period. Figure 6 The curve in the figure shows obvious fluctuations, indicating that the high-frequency flutter disturbance signal was successfully injected into the high-frequency injection module; the high-frequency injection module generates a PWM duty cycle signal to drive the solenoid valve, and the PWM duty cycle modulation result is as follows. Figure 7 As shown.

[0099] Example 3

[0100] See Figure 8 This embodiment also proposes a solenoid valve chatter disturbance signal injection control system, the system 800 comprising:

[0101] The acquisition module 810 is used to acquire the injection frequency and controller cutoff frequency of the user's flutter disturbance signal;

[0102] Selection module 820 is used to select an injection module based on the injection frequency and controller cutoff frequency of the flutter disturbance signal. If the injection frequency is lower than the controller cutoff frequency, the injection module is selected as a low-frequency injection module; otherwise, the injection module is selected as a high-frequency injection module.

[0103] The first drive module 830 is used to drive the solenoid valve by generating a PWM duty cycle signal with a low-frequency injection module.

[0104] The second drive module 840 is used to drive the solenoid valve by generating a PWM duty cycle signal using a high-frequency injection module.

[0105] In this embodiment, a switching control strategy is studied. First, the injection frequency and controller cutoff frequency of the user's flutter disturbance signal are obtained. Then, based on the injection frequency and controller cutoff frequency, the injection module is selected as a low-frequency injection module or a high-frequency injection module. The low-frequency injection module or the high-frequency injection module is then used to generate a PWM duty cycle signal to drive the solenoid valve. The flutter disturbance signal injection switching control strategy of this invention can inject a flutter disturbance signal of a specific frequency according to user needs, satisfying the user's required flutter injection strategy. Moreover, the flutter frequency of the injected flutter disturbance signal is not affected by the circuit parameter design. It not only meets the requirements of the field working conditions, but also ensures that the system has a wide frequency injection range, thereby overcoming the influence of hydraulic viscosity on the rapid adjustment of the system and assisting field engineers in achieving efficient automated project debugging.

[0106] The embodiments described are merely examples to clearly illustrate the present invention and are not intended to limit the implementation of the invention. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively describe all possible implementations. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A solenoid valve chattering disturbance signal injection control method characterized by, Includes the following steps: S1. Obtain the injection frequency and controller cutoff frequency of the user's flutter disturbance signal; S2. Select an injection module based on the injection frequency of the flutter disturbance signal and the controller cutoff frequency. If the injection frequency is lower than the controller cutoff frequency, select a low-frequency injection module and proceed to step S3. Otherwise, select the high-frequency injection module and proceed to step S4; S3. A PWM duty cycle signal is generated by a low-frequency injection module to drive the solenoid valve; the low-frequency injection module is equipped with a signal terminal for receiving reference current signal and low-frequency flutter disturbance signal injection, a controller, a solenoid valve and a data acquisition circuit. The signal terminal is connected to the input terminal of the controller, the output terminal of the controller is connected to the input terminal of the solenoid valve, the output terminal of the solenoid valve is connected to the input terminal of the data acquisition circuit, and the output terminal of the data acquisition circuit is connected back to the signal terminal to form a control loop. S4. A PWM duty cycle signal is generated by a high-frequency injection module to drive the solenoid valve; the high-frequency injection module is provided with a signal terminal for receiving a reference current signal, a controller, an injection terminal for injecting high-frequency flutter disturbance signals, a solenoid valve, a data acquisition circuit, and a notch filter. The signal terminal is connected to the input terminal of the controller, the output terminal of the controller is connected to the injection terminal, the injection terminal is connected to the input terminal of the solenoid valve, the output terminal of the solenoid valve is connected to the input terminal of the data acquisition circuit, the output terminal of the data acquisition circuit is connected to the input terminal of the notch filter, and the output terminal of the notch filter is connected back to the signal terminal, forming a control loop.

2. The electromagnetic valve chatter disturbance signal injection control method according to claim 1, characterized in that, S1 also acquires the amplitude of the user's flutter disturbance signal. In the low-frequency injection module, a sinusoidal disturbance signal is generated based on the injection frequency and amplitude of the user's flutter disturbance signal. This signal is then superimposed on the signal terminal of the control loop of the low-frequency injection module along with the desired current as the overall desired reference signal.

3. The electromagnetic valve chatter disturbance signal injection control method according to claim 2, characterized in that, The process of using a low-frequency injection module to generate a PWM duty cycle signal to drive the solenoid valve is as follows: S31. The signal terminal in the low-frequency injection module receives the input reference current signal and the low-frequency flutter disturbance signal; S32. At the signal terminal, the input reference current signal and low-frequency flutter disturbance signal are subtracted from the feedback current signal of the solenoid valve to obtain the difference value. The difference value is used as the input signal of the controller, and the controller outputs the PWM duty cycle signal to the input terminal of the solenoid valve. S33. The acquisition circuit acquires the current signal output by the solenoid valve, and injects the output feedback current into the signal terminal. The signal terminal transmits the reference current signal, feedback current and low-frequency flutter signal back to the controller to complete the closed-loop drive control of the low-frequency injection module.

4. The electromagnetic valve chatter disturbance signal injection control method according to claim 1, characterized in that, The process of using a high-frequency injection module to generate a PWM duty cycle signal to drive the solenoid valve is as follows: S41. The signal terminal in the high-frequency injection module receives the input reference current signal, calculates the difference between it and the output signal of the notch filter, and uses the difference as the input of the controller. S42. The controller outputs a drive signal PWM1, sets the duty cycle signal equivalent to the high-frequency jitter disturbance signal to PWM2, adds the two signals at the injection terminal, and outputs them to the input terminal of the solenoid valve. S43. The acquisition circuit acquires the current signal output by the solenoid valve and outputs it to the notch filter; S44. The notch filter filters the received current signal and outputs a feedback current that is injected into the signal terminal. The signal terminal then transmits the reference current signal and the feedback current to the controller to complete the closed-loop drive control of the high-frequency injection module.

5. The electromagnetic valve chatter disturbance signal injection control method according to claim 4, characterized in that, The notch filter filters the received current signal Is. The specific filtering calculation formula is as follows: W(k)=Is(k)+2*r*cos(ω0)*W(k-1)- r*r*W(k-2) (k)=W(k)- 2*cos(ω0)*W(k-1)+ W(k-2) Where k represents the current control cycle, W(k) represents the intermediate variable data of the notch filter in the k-th control cycle, Is(k) represents the current signal acquired by the acquisition circuit in the k-th control cycle, r represents the notch constant, and ω0 represents the digital frequency of the notch filter, ω0=2πf d / f s f d f represents the flutter frequency of the flutter disturbance signal. s Let W(k-1) represent the sampling frequency of the closed-loop control, W(k-1) represent the intermediate variable data of the notch filter in the (k-1)th control cycle, and W(k-2) represent the intermediate variable data of the notch filter in the (k-2)th control cycle. (k) represents the feedback current output by the notch filter.

6. The electromagnetic valve chatter disturbance signal injection control method according to claim 5, characterized in that, The controller processes the input signal, and the specific processing procedure is as follows: S451. Based on the reference current signal and the feedback current, calculate the current error signal. The specific calculation expression is as follows: err(k)=I_ref(k)- (k) Where err(k) represents the current error signal of the kth control cycle, and I_ref(k) represents the reference current signal of the kth control cycle; S452. Based on the current error signal, calculate the control quantity y of the controller. The specific calculation expression is as follows: in, This represents the intermediate variable of the controller in the k-th control cycle. This represents the proportional parameter of the controller. This represents the integral parameter of the controller. 1,2,3…,k, This represents the cumulative value of the error current signal from the j-th control cycle to the k-th control cycle; S453. Based on the intermediate variable y(k) of the controller, calculate the PWM duty cycle. The specific calculation expression is as follows: in, This indicates the duty cycle of the PWM output signal from the control circuit. Indicates bus voltage. This represents the equivalent PWM duty cycle of the jitter disturbance signal in the k-th control cycle.

7. The electromagnetic valve chatter disturbance signal injection control method according to any one of claims 2-5, characterized in that, The reference current signal is the current signal output by the outer loop displacement controller.

8. A control system for injecting electromagnetic valve chatter disturbance signals, characterized in that, The system includes: The acquisition module is used to acquire the injection frequency and controller cutoff frequency of the user's flutter disturbance signal; The selection module is used to select an injection module based on the injection frequency of the flutter disturbance signal and the controller cutoff frequency. If the injection frequency is lower than the controller cutoff frequency, the injection module is selected as a low-frequency injection module; otherwise, the injection module is selected as a high-frequency injection module. The first driving module is used to drive the solenoid valve by generating a PWM duty cycle signal using a low-frequency injection module. The low-frequency injection module is equipped with a signal terminal for receiving a reference current signal and a low-frequency flutter disturbance signal injection, a controller, a solenoid valve, and a data acquisition circuit. The signal terminal is connected to the input terminal of the controller, the output terminal of the controller is connected to the input terminal of the solenoid valve, the output terminal of the solenoid valve is connected to the input terminal of the data acquisition circuit, and the output terminal of the data acquisition circuit is connected back to the signal terminal, forming a control loop. The second driving module is used to drive the solenoid valve by generating a PWM duty cycle signal using a high-frequency injection module. The high-frequency injection module includes a signal terminal for receiving a reference current signal, a controller, an injection terminal for injecting high-frequency flutter disturbance signals, a solenoid valve, a data acquisition circuit, and a notch filter. The signal terminal is connected to the input terminal of the controller, the output terminal of the controller is connected to the injection terminal, the injection terminal is connected to the input terminal of the solenoid valve, the output terminal of the solenoid valve is connected to the input terminal of the data acquisition circuit, the output terminal of the data acquisition circuit is connected to the input terminal of the notch filter, and the output terminal of the notch filter is connected back to the signal terminal, forming a control loop.

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