A PID controller with arbitrary waveform stability and control method

Abstract

This invention discloses an arbitrary waveform stabilization PID controller and control method, belonging to the field of PID control technology. This device adds arbitrary waveform storage functionality to the basic PID controller, including a storage chip and a processing chip. The storage chip stores any user-defined stable target waveform. The processing chip includes a waveform reading module and a PID controller. The waveform reading module reads the waveform value of the stable target waveform according to a time sequence. The PID controller performs PID feedback control based on the read waveform value and the signal to be stabilized output by the controlled system, ensuring that the state of the signal to be stabilized in the controlled system follows the stable target waveform. This invention, by modifying the structure of existing stabilization schemes, enables the actual waveform to more closely approximate the target waveform, effectively reducing tracking errors. This invention can be applied to both digital PID and analog PID controllers.

Description

Technical Field

[0001] This invention relates to the field of PID control technology, and more specifically to a PID controller and control method that is stable with arbitrary waveforms. Background Technology

[0002] In industrial production and scientific research, it is often necessary to control a specific state variable (voltage, current, velocity, temperature, laser intensity, etc.) of a controlled system to operate according to a target waveform. When the state variable of the controlled system needs to change at high speed, over a wide range, and without simple regularity, a control method using an external signal source and a proportional-integral-derivative (PID) controller is typically employed. The external signal source provides a time-varying reference signal, which can be set by the user or generated by other systems. The PID controller is a module or device with feedback control functionality. The PID module calculates the difference between the target value and the value to be stabilized to obtain an error signal. The proportional, integral, and derivative terms of the error signal are then weighted and summed as a feedback signal to the controller, thereby achieving signal stabilization within a certain bandwidth. Specifically, current technology uses an external signal source to provide the target waveform to be stabilized, inputting it to the PID input port as a reference signal, thus using the PID to lock the state variable to be stabilized onto this changing waveform.

[0003] Based on their implementation, PID controllers can be divided into two types: digital PID and analog PID. Digital PID is implemented using digital circuits. Its main principle is that an analog-to-digital converter (ADC) samples the signal, and an FPGA or CPU calculates the feedback signal based on the sampling results. This feedback signal is then output to the controller via a digital-to-analog converter (DAC), thereby stabilizing the signal. The advantages of digital PID are programmability, functional flexibility, and rapid development. Analog PID, on the other hand, utilizes analog circuits. It primarily uses operational amplifiers and components such as capacitors and resistors to build proportional, integral, and differential circuits to achieve feedback control. The advantages of analog PID are large bandwidth and fast feedback.

[0004] The existing technology has the following main drawbacks:

[0005] 1. Signal transmission between the signal source and the PID controller increases locking error. First, the signal source internally converts the signal to an analog signal via a digital-to-analog converter (DAC), then connects it to the PID controller via a coaxial cable for reference. The PID controller then converts the signal back to a digital signal via an analog-to-digital converter (ADC) for processing by the arithmetic chip. This two-stage digital-to-analog conversion increases quantization error. Second, analog signals transmitted via coaxial cables are susceptible to electromagnetic interference and attenuation, leading to signal distortion and discrepancies from the required stable waveform.

[0006] 2. PID controllers cannot know the entire waveform that needs to be stabilized; they can only receive the reference signal in real time, and the PID parameters remain unchanged throughout the process. Since different PID parameters are needed to minimize tracking error when the waveform is stable and when it changes drastically, this configuration only allows the PID to select one parameter. Therefore, it may produce large signal overshoot or even self-oscillation (if the feedback parameter is set too high), or it may fail to track the input signal well (if the feedback parameter is set too low), and it cannot perform global optimization according to the required waveform.

[0007] 3. It requires the simultaneous use of PID and signal source. As two independent devices, PID and signal source require separate chassis, power supply, high-precision digital-to-analog converter, and filter chip, which takes up a lot of space and involves redundancy of multiple devices. Summary of the Invention

[0008] In view of this, the present invention provides an arbitrary waveform stabilized PID controller and control method to at least solve some of the technical problems in the background art. The arbitrary waveform stabilized PID controller disclosed in the technical solution of the present invention can also be called AWPID (Arbitrary waveform stabilized Proportional-integral-derivative controller).

[0009] To achieve the above objectives, the present invention adopts the following technical solution:

[0010] In one embodiment, the present invention discloses an arbitrary waveform stable PID controller, the AWPID controller comprising: a memory chip and a computing chip;

[0011] The memory chip is used to store any stable target waveform of the user;

[0012] The computing chip includes a waveform reading module and a PID controller;

[0013] The waveform reading module is used to read the waveform values ​​of the stable target waveform according to a time series.

[0014] The PID controller is used to perform PID feedback control based on the read waveform value and the signal to be stabilized output by the controlled system, so that the state of the signal to be stabilized of the controlled system follows the movement of the stable target waveform.

[0015] Preferably, the PID controller in the arbitrary waveform stable PID controller disclosed in this invention is implemented using an enhanced PID algorithm. Specifically, the PID controller includes...

[0016] The feedforward optimization module is used to determine the feedforward compensation value based on the waveform change of the stable target waveform stored in the memory chip at the current moment relative to the previous moment.

[0017] The feedforward correction module is used to correct the feedforward compensation value output by the feedforward optimization module based on the input and output response values ​​of the PID controller.

[0018] The parameter optimization module is used to update and optimize the PID parameters of the conventional PID calculation module according to the error signal over a set time period. The error signal is obtained from the output value of the controlled system and the stable target waveform stored in the storage chip.

[0019] The standard PID calculation module is used to perform PID control on the current error signal based on the updated and optimized PID parameters, and obtain the initial PID control result;

[0020] The summation output module is used to sum the corrected feedforward compensation value obtained by the feedforward correction module and the initial PID control result obtained by the conventional PID calculation module to obtain the final enhanced PID control result.

[0021] Preferably, the parameter optimization module updates and optimizes the PID parameters of the conventional PID calculation module based on the error signal over a set time period, specifically including:

[0022] Calculate the spectral intensity of the error signal and divide the spectral intensity into three segments: low, medium, and high, based on a set threshold.

[0023] If the maximum value of the waveform amplitude within the low-band spectral intensity range is greater than the set first amplitude threshold, then increase the integral parameter K. p To eliminate low-frequency noise;

[0024] If the maximum waveform amplitude value within the mid-range spectral intensity range exceeds the set second amplitude threshold, then increase the proportional parameter K. i To suppress low-frequency noise, while increasing the differential parameter K d In order to suppress high-frequency noise;

[0025] The monitoring system monitors the oscillation frequency range. When the maximum amplitude value of the waveform within the oscillation frequency range exceeds the set third amplitude threshold, the integral parameter K is simultaneously decreased. p , proportional parameter K i and differential parameter K d .

[0026] Preferably, in the feedforward correction module, the feedforward compensation value output by the feedforward optimization module is corrected based on the input and output response values ​​of the PID controller, specifically including the following expression:

[0027]

[0028] in, Indicates feedforward correction module The corrected feedforward compensation value output at each time step; This represents the feedforward compensation value output by the feedforward optimization module. This represents the first derivative of the input with respect to the output of the PID controller, i.e., the input-output response value. Describing the first derivative The size of the interval for segmented storage; express The output voltage of the PID at time t.

[0029] Preferably, the PID controller also includes a response monitoring module for recording the input and output response values ​​of the PID controller with any stable waveform.

[0030] Preferably, any of the above-mentioned PID controllers for stabilizing arbitrary waveforms disclosed in this invention further includes a trigger module, which is used to receive a trigger signal, and the trigger signal is used to trigger the waveform reading module to read the waveform value of the stable target waveform according to the time sequence.

[0031] Preferably, any of the above-mentioned PID controllers with stable arbitrary waveforms disclosed in this invention further includes a freeze module, which is used to receive a freeze signal, and the freeze signal is used to freeze the waveform value of the target waveform and suspend the PID feedback control.

[0032] In another embodiment, the present invention discloses another PID controller with stable arbitrary waveform, which is implemented using digital circuitry and includes:

[0033] Memory chips, analog-to-digital converter chips, computing chips, and digital-to-analog converter chips;

[0034] The memory chip is used to store any stable target waveform of the user;

[0035] The analog-to-digital converter chip is used to receive the analog signal to be stabilized output by the controlled system and convert it into a digital signal;

[0036] The computing chip includes a waveform reading module and a digital PID controller;

[0037] The waveform reading module is used to read the values ​​of a stable target waveform according to a time series.

[0038] The digital PID controller is used to perform PID feedback control based on the read target waveform and the digital signal output by the analog-to-digital converter chip, and outputs a feedback digital signal.

[0039] The digital-to-analog converter chip is used to convert the feedback digital signal into an analog signal that acts on the controlled system, so that the state of the analog signal to be stabilized in the controlled system follows the movement of the stable target waveform stored in the memory chip.

[0040] In a third embodiment, the present invention also discloses an arbitrary waveform stable PID controller, which is implemented using analog circuitry and includes:

[0041] Memory chips, computing chips, analog PID controllers, and digital-to-analog converter chips;

[0042] The memory chip is used to store arbitrary stable target waveform data of the user;

[0043] The computing chip includes a waveform reading module, which is used to read the waveform value of the stable target waveform according to a time series.

[0044] The digital-to-analog converter chip is used to convert the waveform value of the stable target waveform into an analog quantity;

[0045] The analog PID controller is used to perform PID feedback control based on the analog quantity converted from the waveform value and the analog signal to be stabilized output by the controlled system, so that the state of the analog signal to be stabilized of the controlled system follows the movement of the stable target waveform stored in the memory chip.

[0046] On the other hand, the present invention also discloses an arbitrary waveform stable PID control method, which uses the arbitrary waveform stable PID controller described in any one of the above claims to realize the control of the controlled system.

[0047] As can be seen from the above technical solution, compared with the prior art, the present invention discloses a PID control and control method with stable arbitrary waveforms, which has the following beneficial effects:

[0048] 1. Because the parameters of a PID controller need to be adjusted according to the characteristics of the error signal (actual waveform - target waveform), when the target waveform is a constant, the error signal is mainly contributed by environmental noise; when the target waveform is an arbitrary waveform, the error signal is mainly contributed by arbitrary waveforms. These two types of signals differ significantly in power and energy spectrum. Therefore, the optimal operating parameters of the PID controller required to reduce these two types of error signals are inconsistent and highly likely to conflict. The PID controller (AWPID) disclosed in this invention grasps the information of the entire waveform during operation. It can introduce an intelligent PID algorithm during operation, optimizing the PID parameters in real time based on subsequent waveforms and current environmental noise characteristics. This improves the tracking performance of the physical quantity to the input and further reduces the tracking error of the feedback system.

[0049] 2. Compared to existing schemes that combine signal sources and PID controllers, the arbitrary waveform stable PID controller (AWPID) disclosed in this invention reduces the three steps of signal source generating a reference signal, reference signal transmission to the PID, and PID sampling of the reference signal. This eliminates noise and interference introduced in these three steps, allowing the actual waveform to more closely approximate the target waveform and reducing locking errors. Analog AWPID reduces the distance the reference signal travels to the PID, minimizing interference and attenuation during reference signal transmission.

[0050] 3. Compared with existing schemes that combine signal sources and PID controllers, the arbitrary waveform stable PID controller disclosed in this invention reduces the chassis and power supply required by both the signal source and PID controller, thereby improving system integration and further reducing size. Attached Figure Description

[0051] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0052] Figure 1 This is a schematic diagram of a control system architecture in the prior art that uses an external signal source and a common PID controller to achieve stability of arbitrary waveforms.

[0053] Figure 2 This is a schematic diagram of the hardware connection for the PID controller with stable feedback when the arbitrary waveform is working stably, as provided by the present invention.

[0054] Figure 3 A schematic diagram illustrating the core principle of the AWPID controller provided by this invention.

[0055] Figure 4 A schematic diagram of the AWPID structure implemented using digital circuits provided for this invention.

[0056] Figure 5 This is a schematic diagram of the AWPID structure implemented using analog circuits, provided by the present invention.

[0057] Figure 6 The present invention provides a digital AWPID with triggering, freezing functions and intelligent feedforward correction PID algorithm.

[0058] Figure 7 A schematic diagram illustrating the principle of the PID intelligent algorithm framework provided by this invention.

[0059] Figure 8The diagram shows the connection between the signal source and the PID controller required for stabilizing the state variables of the PID controller in the existing scheme.

[0060] Figure 9 A schematic diagram of the enhanced digital AWPID device without a signal source provided by the present invention.

[0061] Figure 10 This diagram illustrates the stable performance of the existing PID algorithm.

[0062] Figure 11 This is a schematic diagram illustrating the effect of the intelligent feedforward correction PID algorithm provided by the present invention. Detailed Implementation

[0063] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0064] In existing technologies, a schematic diagram of using an external signal source in conjunction with a PID controller to achieve arbitrary waveform stabilization is shown below. Figure 1 As shown, the PID controller output is connected to the controller of the controlled system, and the state variables of the controlled system are connected to the PID controller input. The PID controller adjusts its output in real time by comparing the error between the input signal and the reference input, forming a closed-loop feedback system that stabilizes the state variables of the controlled system at a preset waveform. The signal source provides the reference input, allowing the entire system to operate according to the preset waveform. If there is only an external signal source without a PID controller, the signal to be stabilized will not perfectly conform to the preset waveform due to environmental noise and system drift, resulting in significant errors. If there is only a PID controller without an external signal source, the signal to be stabilized will be locked at a fixed point and cannot change over time.

[0065] To address the aforementioned problems, this invention discloses a novel device for realizing the time-varying state variables through feedback control, named an Arbitrary Waveform Stabilized Proportional-Integral-Differential Controller (AWPID). This invention allows users to directly set the reference waveform for the PID, enabling it to stabilize the state variables on any waveform. This invention simplifies the system architecture required to achieve arbitrary waveform stabilization, and simultaneously optimizes the stabilization effect, resulting in smaller errors.

[0066] The hardware system connection diagram for steady-state quantities of this invention is shown below. Figure 2 As shown, compared with the existing solution of external signal source + PID, the technical solution of the present invention does not have a separate signal source to provide a reference signal, but directly stores the reference signal in AWPID.

[0067] This invention achieves this function by designing a new device called AWPID, which is an arbitrary waveform stable PID controller. The core solution is as follows: Figure 3 As shown. AWPID is an enhanced PID controller that can stabilize arbitrary waveforms without receiving an external analog reference signal. Its main principle is to add a memory chip inside the AWPID controller to store the target waveform. A regular PID controller receives the signal to be stabilized and simultaneously receives a reference input; the error signal is the signal to be stabilized minus the reference input. Before running, AWPID stores the target waveform in the memory chip. The waveform reading module reads the target waveform from the memory chip, and when it receives the signal to be stabilized, the error signal is the signal to be stabilized minus the target waveform.

[0068] In one embodiment, the present invention can be implemented using digital circuits, and its specific implementation method is as follows: Figure 4 As shown. In the digital implementation, the PID controller with stable arbitrary waveforms includes a memory chip, an analog-to-digital converter chip, an arithmetic chip, and a digital-to-analog converter chip. Other accessories may include a power supply module and a chassis. The functions of each component are described in detail below:

[0069] The processing chip includes a waveform reading module and a PID algorithm module. The waveform reading module reads waveforms from the memory chip according to a set sampling rate. The PID algorithm module compares the digital signal obtained from the analog-to-digital converter chip with the target value of the current time stored in the memory chip to obtain an error signal. The PID algorithm then runs to obtain a feedback output digital signal based on the error signal.

[0070] Analog-to-digital converter chip: Receives the signal of the variable to be stabilized and converts the analog signal into a digital signal, facilitating subsequent processing by the computing chip.

[0071] Storage chips: Storage requires a stable target value, which is a state quantity that changes over time. Compressed or uncompressed data can be stored or retrieved directly over time.

[0072] Digital-to-analog converter chip: Converts the digital signal output from the feedback of the PID algorithm into an analog signal, which then acts on the target system.

[0073] In another implementation, the present invention can also be implemented using analog circuits. A schematic diagram of the specific structure of the analog circuit implementation can be found in [reference needed]. Figure 5As shown, the PID controller for stabilizing any waveform includes a memory chip, a computation chip, an analog PID controller, and a digital-to-analog converter chip. The memory chip stores the user's arbitrary target waveform data. The computation chip includes a waveform reading module, which reads the waveform value of the target waveform according to a time sequence. The digital-to-analog converter chip converts the waveform value of the target waveform into an analog quantity. The analog PID controller performs PID feedback control based on the analog quantity converted from the waveform value and the analog signal to be stabilized output by the controlled system. This allows the state of the analog signal to be stabilized in the controlled system to follow the target waveform stored in the memory chip. In this embodiment, the state of the controlled system is directly input to the analog PID controller, and the memory chip provides the analog PID controller with a reference signal via the digital-to-analog converter chip. The output of the analog PID controller is directly connected to the controlled system, thereby achieving closed-loop feedback.

[0074] As an improvement to any of the above embodiments, such as Figure 6 As shown, this invention can further enhance functionality by adding a trigger port and a freeze port, along with their corresponding trigger and freeze modules. The trigger module receives a trigger signal, which in turn triggers the waveform reading module to read the waveform value of a stable target waveform according to a time sequence. The freeze module receives a freeze signal, which freezes the waveform value of the target waveform and pauses the PID feedback control. In practical applications, the trigger port receives a level signal. When a trigger signal is received, the computing chip starts timing, continuously retrieving the target value from memory at the current time as a reference for the PID. The freeze port determines the freeze time based on the received level signal. When the freeze port receives the freeze signal, the PID is in a frozen state, and its output and internal states remain unchanged. When the freeze port unfreezes, the PID returns to normal operation.

[0075] To further improve performance, the PID controller in the system of this invention employs an intelligent feedforward correction PID algorithm to achieve smaller tracking errors. The intelligent feedforward correction PID algorithm module will be described in detail below.

[0076] Intelligent Feedforward Corrected PID Algorithm Module: By modifying the PID algorithm, this module achieves performance advantages surpassing existing conventional PID algorithm modules on PID controllers with stable waveforms of arbitrary nature. Its specific architecture can be found in [link to module description]. Figure 7As shown, the improved PID controller disclosed in this invention includes a feedforward optimization module, a feedforward correction module, a parameter optimization module, a conventional PID calculation module, and a summation output module. Specifically, the feedforward optimization module is used to determine the feedforward compensation value based on the waveform change of the stable target waveform stored in the memory chip at the current moment relative to the previous moment; the feedforward correction module is used to correct the feedforward compensation value output by the feedforward optimization module based on the input and output response values ​​of the AWPID controller; the parameter optimization module is used to update and optimize the PID parameters of the conventional PID calculation module based on the error signal over a set time period, wherein the error signal is obtained from the output value of the controlled system and the stable target waveform stored in the memory chip; the conventional PID calculation module is used to perform PID control on the current error signal based on the updated and optimized PID parameters and obtain a first PID control result; the summation output module is used to sum the corrected feedforward compensation value obtained by the feedforward correction module and the first PID control result obtained by the conventional PID calculation module to obtain the final enhanced PID control result.

[0077] The intelligent feedforward correction PID algorithm module (replacing the PID controller) proposed in this invention will be described in further detail below. The intelligent feedforward correction PID algorithm module performs the following steps:

[0078] Input: The waveform that needs to be stabilized, acquired by AWPID. This input is the output of the controlled system.

[0079] Reference: Target waveform stored internally by AWPID.

[0080] Error: Input-reference, providing an error signal for conventional PID algorithms.

[0081] Parameter optimization module: Receives and records data over a period of time. The error signal is used to calculate the optimal PID parameter setpoints and update the PID parameters in real time or periodically. This is a PID adaptive module that ensures the PID always operates at its optimal state. The specific algorithm is as follows: The three PID parameters k are saved at any given time. p k i k d and parameter update magnitude U p U i U d The spectral intensity of the error signal is calculated in real time, and based on f l f h Divide the spectrum into 0-f l f l -f h f h -∞ three segments. If in the spectrum 0-f lThe maximum amplitude value within the range is greater than the set value a. l This proves that the noise term has a low-frequency component, so we increase k. i Eliminate low-frequency noise, making k i =k i +U i If in the spectrum f l -f h The maximum amplitude value within the range is greater than the set value a. m This proves that the noise term has a mid-frequency component, so we increase k. p Suppress intermediate frequency noise, so that k p =k p +U p If in the spectrum f h The maximum amplitude value within the range of -∞ is greater than the set value a. h Then increase k d Suppress high-frequency noise, so that k d =k d +U d Simultaneously monitor the oscillation frequency range f of the system. cl with f ch When the spectrum is in the range f cl <f<f ch The maximum value of the internal amplitude is greater than the set value a. c At the same time, reduce k i k p and k d , making k i =k i -U i k p -U p k d =k d -U d This is to prevent the PID controller from self-oscillating. It should be noted that in this application, parameters with the subscript 'l' represent the minimum value, and those with the subscript 'h' represent the maximum value.

[0082] Response monitoring module: Records the output and input responses of the PID controller, i.e., the first derivative D at each output point o. o =d I / d O It should be noted that due to environmental drift, This value is not constant and changes over time, requiring real-time updates using a time-weighted average method. Due to environmental noise interference, It contains noise, but this noise can be filtered out using an averaging algorithm. Specifically, the PID output is discretized into k segments, each segment having a length of δ. o The dividing points are denoted as P1, P2, ... P. kThe first derivatives D1, D2, ... D of each output interval are stored in k variables. k At any given time, the PID controller can obtain the difference d between the current output and the previous output. o And the current input and the previous input d I The difference is updated using a time moving average algorithm. ,in Before the update 'a' represents the parameter that needs to be adjusted. The time-moving average algorithm ensures that the latest data has a high weight, while historical data keeps the calculation of the first derivative stable, preventing drastic parameter changes.

[0083] Conventional PID Algorithm: The conventional PID algorithm consists of three parts: proportional, integral, and derivative, and is the core component of the feedback system. In an AWPID system, the output of the conventional PID is added to the output of the feedforward optimization module to obtain the final output. This module receives the parameters k of P, I, and D set by the parameter optimization module. p k i k d It also receives error signals as input. Its output update logic is as follows: E t E represents the error signal at time t. t-1 This represents the error signal at time t-1 (the previous time).

[0084] Feedforward optimization module: Based on the change of the reference waveform at the current moment relative to the previous moment and the current output of the PID, the magnitude of the feedforward compensation is determined. The output value of the feedforward optimization module is the reference value at the current moment. Compared with the reference value at the previous moment The difference. That is... For AWPID, the reference value can be obtained directly from memory.

[0085] Feedforward Correction Module: Based on the instructions from the feedforward optimization module and combined with the system's historical operating status, the module corrects the magnitude of the PID feedforward. Its output expression is: .

[0086] Output: The final output of the intelligent algorithm The output mainly consists of two parts: the output of a conventional PID algorithm with a parameter optimization module. and the output of the feedforward correction module .

[0087] The core principle of the PID-enhanced intelligent feedforward correction algorithm disclosed in this invention is to decompose the error into unpredictable environmental errors and predictable errors of the objective function. The unpredictable errors are eliminated by conventional PID, while the errors introduced by changes in the objective function are eliminated by the response monitoring module, the feedforward control module, and the feedforward correction module.

[0088] The beneficial effects and principles of this application will be further explained below in conjunction with existing technologies.

[0089] Figure 8 This is a schematic diagram of a prior art system where the signal source and PID are separated. The signal source and PID are two independent devices, and the power supply module, arithmetic chip, digital-to-analog converter chip, and analog-to-digital converter chip are present in both devices.

[0090] Figure 9 The diagram shows the hardware structure of the enhanced digital AWPID device without a signal source disclosed in this invention. As can be seen, the AWPID disclosed in this application simplifies the redundancy of the signal source and PID devices, achieving the same function with a single device. By modifying the PID to integrate a memory chip, it is upgraded to an AWPID, replacing both the signal source and PID devices in the function of stabilizing arbitrary waveforms. Since the AWPID eliminates multiple analog-to-digital converters and avoids wiring between devices, it can effectively reduce tracking errors.

[0091] Another key aspect of the core solution of this invention is that the PID parameters are changed in real time through an intelligent algorithm module, and the error signal caused by changes in the target waveform is reduced through feedforward optimization and feedforward correction modules. Since the AWPID internally stores the waveform that needs to be stable, the optimal PID parameters for each moment can be calculated before the PID runs or the optimal PID parameters for this waveform can be calculated in real time during the run. The PID parameters that can be changed in real time can be optimized for the current and subsequent waveforms, thereby reducing the difference between the final waveform and the target waveform.

[0092] Because AWPID stores the target waveform and adds an intelligent algorithm module, it is possible for AWPID to intelligently adjust parameters according to real-time conditions.

[0093] In existing technologies for stabilizing arbitrary waveforms using a signal source and PID controller, intelligent algorithms can optimize PID parameters based on historical environmental noise. However, during sudden waveform changes, the PID controller may overshoot and fail to effectively follow the waveform. For specific stabilization results, please refer to... Figure 10 As shown, the blue line is the target curve, and the yellow line is the stable effect of the PID. The spikes in the yellow line are mainly contributed by environmental noise. Since the PID and the signal source are two separate devices, the PID control has a large error and cannot effectively follow the signal.

[0094] In the simple case above, a key factor is the rapid change in the PID error signal. This error signal consists of two parts: one is noise and drift caused by the environment, and the other is the error signal caused by changes in the target. Normally, environmental noise and drift are unpredictable, characterized by small noise amplitude and slow drift speed. However, the target is user-defined and requires large and rapid changes. But in the task of executing stable parameters, its waveform is completely known. This can be addressed by optimizing the PID algorithm.

[0095] The stabilization effect after using AWPID to store the target waveform and adding an intelligent algorithm module is as follows: Figure 11 As shown in the diagram, AWPID uses an intelligent PID algorithm. Under the same parameters, AWPID's feedforward optimization module can achieve better control by utilizing the future moment information of the stored waveform, enabling the PID control to follow the target well.

[0096] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0097] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A PID controller stable with arbitrary waveforms, characterized in that, include: Memory chips and computing chips; The memory chip is used to store any stable target waveform of the user; The computing chip includes a waveform reading module and a PID controller; The waveform reading module is used to read the waveform values ​​of the stable target waveform according to a time series. The PID controller is used to perform PID feedback control based on the read waveform value and the signal to be stabilized output by the controlled system, so that the state of the signal to be stabilized of the controlled system follows the movement of the target waveform. The PID controller includes, The feedforward optimization module is used to determine the feedforward compensation value based on the waveform change of the stable target waveform stored in the memory chip at the current moment relative to the previous moment. The feedforward correction module is used to correct the feedforward compensation value output by the feedforward optimization module based on the input and output response values ​​of the PID controller. The parameter optimization module is used to update and optimize the PID parameters of the conventional PID calculation module according to the error signal over a set time period. The error signal is obtained from the output value of the controlled system and the stable target waveform stored in the storage chip. The standard PID calculation module is used to perform PID control on the current error signal based on the updated and optimized PID parameters, and obtain the initial PID control result; The summation output module is used to sum the corrected feedforward compensation value obtained by the feedforward correction module and the initial PID control result obtained by the conventional PID calculation module to obtain the final enhanced PID control result.

2. The PID controller with arbitrary waveform stability according to claim 1, characterized in that, The parameter optimization module updates and optimizes the PID parameters of the conventional PID calculation module based on the error signal over a set time period, specifically including: Calculate the spectral intensity of the error signal and divide the spectral intensity into three segments: low, medium, and high, based on a set threshold. If the maximum value of the waveform amplitude within the low-band spectrum intensity range is greater than the set first amplitude threshold, then increase the integral parameter K. p To eliminate low-frequency noise; If the maximum waveform amplitude value within the mid-range spectral intensity range exceeds the set second amplitude threshold, then increase the proportional parameter K. i To suppress low-frequency noise, while increasing the differential parameter K d To suppress high-frequency noise; The monitoring system monitors the oscillation frequency range. When the maximum amplitude value of the waveform within the oscillation frequency range exceeds the set third amplitude threshold, the integral parameter K is simultaneously decreased. p , proportional parameter K i and differential parameter K d .

3. The PID controller with arbitrary waveform stability according to claim 1, characterized in that, In the feedforward correction module, the feedforward compensation value output by the feedforward optimization module is corrected based on the input and output response values ​​of the PID controller, specifically including the following expressions: Among them, O t，2 Indicates feedforward correction module O t，2 The corrected feedforward compensation value output at time step F; t D represents the feedforward compensation value output by the feedforward optimization module. o δ represents the first derivative of the input with respect to the output of a PID controller, i.e., the input-output response value; O D represents the first derivative. o The size of the interval for segmented storage; O t-1 This represents the output voltage of the PID at time t-1.

4. The PID controller with arbitrary waveform stability according to claim 1, characterized in that, It also includes a response monitoring module for recording the input and output response values ​​of the PID controller.

5. The PID controller with arbitrary waveform stability according to claim 1, characterized in that, It also includes a trigger module, which is used to receive a trigger signal, which is used to trigger the waveform reading module to read the waveform value of the stable target waveform according to the time sequence.

6. The PID controller with arbitrary waveform stability according to claim 1, characterized in that, It also includes a freeze module, which is used to receive a freeze signal, which is used to freeze the waveform value of the target waveform and suspend the PID feedback control.

7. A PID controller stable with arbitrary waveforms, characterized in that, The PID controller is implemented using digital circuitry, including: Memory chips, analog-to-digital converter chips, computing chips, and digital-to-analog converter chips; The memory chip is used to store any stable target waveform of the user; The analog-to-digital converter chip is used to receive the analog signal to be stabilized output by the controlled system and convert it into a digital signal; The computing chip includes a waveform reading module and a digital PID controller; The waveform reading module is used to read the values ​​of a stable target waveform according to a time series. The digital PID controller is used to perform PID feedback control based on the read target waveform and the digital signal output by the analog-to-digital converter chip, and outputs a feedback digital signal. The digital-to-analog converter chip is used to convert the feedback digital signal into an analog signal that acts on the controlled system, so that the state of the analog signal to be stabilized in the controlled system follows the movement of the stable target waveform stored in the storage chip. The PID controller includes, The feedforward optimization module is used to determine the feedforward compensation value based on the waveform change of the stable target waveform stored in the memory chip at the current moment relative to the previous moment. The feedforward correction module is used to correct the feedforward compensation value output by the feedforward optimization module based on the input and output response values ​​of the PID controller. The parameter optimization module is used to update and optimize the PID parameters of the conventional PID calculation module according to the error signal over a set time period. The error signal is obtained from the output value of the controlled system and the stable target waveform stored in the storage chip. The standard PID calculation module is used to perform PID control on the current error signal based on the updated and optimized PID parameters, and obtain the initial PID control result; The summation output module is used to sum the corrected feedforward compensation value obtained by the feedforward correction module and the initial PID control result obtained by the conventional PID calculation module to obtain the final enhanced PID control result.

8. A PID controller stable with arbitrary waveforms, characterized in that, The PID controller is implemented using analog circuitry, including: Memory chips, computing chips, analog PID controllers, and digital-to-analog converter chips; The memory chip is used to store arbitrary stable target waveform data of the user; The computing chip includes a waveform reading module, which is used to read the waveform value of the stable target waveform according to a time series. The digital-to-analog converter chip is used to convert the waveform value of the stable target waveform into an analog quantity; The analog PID controller is used to perform PID feedback control based on the analog quantity converted from the waveform value and the analog signal to be stabilized output by the controlled system, so that the state of the analog signal to be stabilized of the controlled system follows the stable target waveform stored in the memory chip. The PID controller includes, The feedforward optimization module is used to determine the feedforward compensation value based on the waveform change of the stable target waveform stored in the memory chip at the current moment relative to the previous moment. The feedforward correction module is used to correct the feedforward compensation value output by the feedforward optimization module based on the input and output response values ​​of the PID controller. The parameter optimization module is used to update and optimize the PID parameters of the conventional PID calculation module according to the error signal over a set time period. The error signal is obtained from the output value of the controlled system and the stable target waveform stored in the storage chip. The standard PID calculation module is used to perform PID control on the current error signal based on the updated and optimized PID parameters, and obtain the initial PID control result; The summation output module is used to sum the corrected feedforward compensation value obtained by the feedforward correction module and the initial PID control result obtained by the conventional PID calculation module to obtain the final enhanced PID control result.

9. A PID control method for stabilizing arbitrary waveforms, characterized in that, The control of the controlled system is achieved by using the PID controller with arbitrary waveform stability as described in any one of claims 1-8.

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