A photoelectric and electromagnetic composite force balance control system and method

Abstract

This invention relates to the field of force sensor technology, and more particularly to a photoelectric and electromagnetic composite force balance control system and method. The system includes: a differential photoelectric detection module; a PID control module configured to output an electromagnetic force compensation voltage that dynamically responds to displacement deviation in real time; an electromagnetic force execution module connected to the output of the PID control module, configured to generate a reverse balancing force based on a symmetrically wound compensation coil according to the electromagnetic force compensation voltage; a main control module configured to provide synchronous modulation timing to the light-emitting unit and to provide phase-synchronized first and second triangular waves to a dual-channel PWM modulation module; and a dual-channel PWM modulation module. This invention effectively solves the problem of control accuracy degradation caused by electromagnetic coil temperature drift and signal crosstalk in high-precision force balance detection systems, and eliminates the need for AD conversion.

Description

Technical Field

[0001] This invention relates to the field of force sensor technology, and in particular to a control system and method for force balance based on photoelectric and electromagnetic composite forces. Background Technology

[0002] Force balance control systems are a core foundational technology in the field of precision measurement. They maintain the system in mechanical equilibrium by detecting the displacement deviation of moving parts in real time and generating a counterbalancing force. Traditional solutions typically employ single-sensor modes such as photoelectric or electromagnetic sensors, combined with analog PID controllers to achieve closed-loop regulation.

[0003] However, existing technologies suffer from two major drawbacks. First, temperature drift interference is uncontrollable. The coil resistance of the electromagnetic actuator changes significantly with temperature, causing the driving force to deviate from the theoretical value. Existing temperature drift compensation technologies mostly rely on offline calibration or fixed parameter correction, which cannot dynamically respond to real-time changes in coil resistance, leading to a sharp deterioration in the accuracy of the balanced force output under wide temperature range conditions. Second, signal crosstalk is severe. The external force detection signal and the temperature compensation signal overlap in the time and frequency domains. Especially during high-frequency PWM modulation, the switching noise of the drive circuit couples to the temperature sampling channel, while the transient jumps in the temperature signal interfere with the ADC conversion process of displacement detection. Existing technologies use passive suppression methods such as shielding or filtering, which are insufficient to eliminate dynamic crosstalk between signals, resulting in displacement detection distortion and lag in temperature drift compensation. These defects together cause a decrease in system control accuracy and an increase in overshoot oscillation under complex operating conditions.

[0004] The information disclosed in this background section is intended only to enhance the understanding of the general background of this disclosure and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0005] This invention provides a control system and method for balancing photoelectric and electromagnetic composite forces, which can effectively solve the problems in the background art.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A photoelectric and electromagnetic composite force balance control system, the system comprising: A differential photoelectric detection module includes a light-emitting unit, a photosensitive unit, and a differential amplification unit symmetrically arranged on both sides of a movable part. The differential amplification unit is connected to the photosensitive unit and is configured to convert the differential current signal output by the photosensitive unit into a voltage signal and eliminate common-mode interference. The displacement-voltage conversion module is connected to the differential amplifier unit and linearly maps the voltage signal into a displacement deviation voltage according to the adjustable resistor network. The PID control module includes an analog PID circuit composed of an operational amplifier and an RC network. The input terminal of the analog PID circuit is connected to the displacement deviation voltage and configured to output an electromagnetic force compensation voltage that corresponds to the dynamic response of the displacement deviation in real time. The electromagnetic force actuation module includes a current drive circuit connected to the output terminal of the PID regulation module, and is configured based on a symmetrically wound compensation coil to generate a reverse balancing force according to the electromagnetic force compensation voltage. The main control module is configured to provide synchronous modulation timing to the light-emitting unit and to provide phase-synchronized first and second triangular waves to the dual-channel PWM modulation module. The dual-channel PWM modulation module includes a first comparator and a second comparator. The first comparator compares the electromagnetic force compensation voltage with the first triangular wave and outputs a PWMW external force signal representing the external force. The second comparator compares the temperature sensor signal with the second triangular wave and outputs a temperature-compensated PWMT temperature signal.

[0007] Furthermore, the PID control module includes: A proportional control unit, wherein the input terminal of the proportional control unit receives the displacement deviation voltage; An integral control unit, the input of which is connected to the output of the proportional control unit, is used to process the residual error signal output by the proportional control unit; A differential control unit, the input of which is connected to the output of the displacement detection module, is used to detect changes in the motion speed of the movable part; An error amplifier is provided, the inverting input of which is connected to the outputs of the proportional control unit, the integral control unit, and the derivative control unit, respectively, to synthesize a PID control signal. The input terminals of the proportional control unit, the integral control unit, and the derivative control unit can be configured to be simultaneously connected to the displacement detection module, forming a parallel topology.

[0008] Further, the proportional control unit includes: A multi-stage adjustable resistor network is used to set the system stiffness coefficient; The first-stage buffer amplifier is connected to the input terminal of the multi-stage adjustable resistor network; The second-stage buffer amplifier is connected to the output of the multi-stage adjustable resistor network. The resistance value of the multi-stage adjustable resistor network is configured to suppress overshoot oscillation of the movable component.

[0009] Further, the integral control unit includes: An integrating operational amplifier, wherein the non-inverting input terminal of the integrating operational amplifier is grounded; An integrating capacitor is connected between the inverting input terminal and the inverting output terminal of the integrating operational amplifier. A limiting circuit is connected in parallel across the integrating capacitor to prevent integral saturation. The capacitance value of the integrating capacitor is configured such that the integration time constant of the integrating capacitor is greater than the maximum reset period of the movable part.

[0010] Furthermore, the differential control unit includes: A differential operational amplifier whose inverting input receives displacement detection signals through a differential capacitor; A compensation resistor is connected in parallel across the differential capacitor; A phase compensation network is connected to the output of the differential operational amplifier; The capacitance value of the differential capacitor is configured to attenuate the oscillation at the mechanical resonant frequency of the movable component.

[0011] Furthermore, the displacement-voltage conversion module includes: A photodiode configured to receive light signals reflected by the movable component; A transimpedance amplifier converts the optical signal generated by the photodiode into an initial voltage. A programmable gain amplifier amplifies the initial voltage; The upper limit of the gain of the programmable gain amplifier is dynamically matched with the resistance value of the multi-stage adjustable resistor network in the proportional control unit.

[0012] Furthermore, the current driving circuit includes: The full-bridge driver chip has four drive output channels; The first complementary MOS transistor group has its gates connected to the first drive output channel and the second drive output channel of the full-bridge driver chip, respectively. The gates of the second complementary MOS transistor group are respectively connected to the third and fourth drive output channels of the full-bridge driver chip. The full-bridge driver chip is configured to enable the first complementary MOS transistor group to drive the electromagnetic coil in the positive direction when the displacement deviation voltage is positive; and to enable the second complementary MOS transistor group to drive the electromagnetic coil in the reverse direction when the displacement deviation voltage is negative; and the first complementary MOS transistor group and the second complementary MOS transistor group are prohibited from being turned on simultaneously.

[0013] Furthermore, the main control module is configured to include: Receive the PWMT temperature signal and analyze the duty cycle of the PWMT temperature signal; Calculate the resistance temperature drift coefficient of the electromagnetic coil based on the duty cycle described in the analysis; The output amplitude of the first triangular wave generator is dynamically adjusted according to the resistance temperature drift coefficient. The resistance variation of the electromagnetic coil is compensated based on the output amplitude of the generator to maintain a constant electromagnetic force output.

[0014] Furthermore, the main control module is also configured to include: Monitor the rising edge of the PWMW external force signal; During the rising edge of the PWMW external force signal, the input signal transmitted to the temperature compensation channel drive circuit is blocked. Capture the peak sampling points of the PWMT temperature signal; During the peak sampling period of the PWMT temperature signal, the acquisition of the displacement signal is paused.

[0015] A method for controlling the balance of photoelectric and electromagnetic combined forces, the method comprising: Synchronous modulated light is emitted by the light-emitting units on both sides of the movable part. The photosensitive unit receives the differential light signal reflected by the movable part and generates a differential current signal. The differential current signal is then converted into an initial voltage signal based on the differential amplification unit. The initial voltage signal is input into an adjustable resistor network for linear mapping, and the displacement deviation voltage is output. The displacement deviation voltage is input into an analog PID circuit to generate an electromagnetic force compensation voltage. According to the polarity of the electromagnetic force compensation voltage, the full-bridge driver chip is controlled to enable the first complementary MOS transistor group or the second complementary MOS transistor group, and the driving current flows in the forward or reverse direction through the symmetrically wound compensation coil to generate a reverse balancing force. The electromagnetic force compensation voltage is compared with the first triangular wave provided by the main control module to output the PWMW external force signal, and the temperature sensor signal is compared with the second triangular wave provided by the main control module to output the PWMT temperature signal. The main control module analyzes the duty cycle of the PWMT temperature signal to calculate the resistance temperature drift coefficient of the electromagnetic coil and dynamically adjusts the amplitude of the first triangular wave to compensate for the electromagnetic force output. The drive signal of the temperature compensation channel is blocked during the rising edge of the PWMW external force signal, and the acquisition operation of the displacement signal is paused during the peak sampling period of the PWMT temperature signal.

[0016] The technical solution of this invention can achieve the following technical effects: It effectively solves the problem of control accuracy degradation caused by electromagnetic coil temperature drift and signal crosstalk in high-precision force balance detection systems, and eliminates the need for AD conversion.

[0017] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0018] 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 some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of a control system based on photoelectric and electromagnetic combined force balance. Figure 2 This is a schematic diagram of the PID control module; Figure 3 This is a schematic diagram of the displacement-voltage conversion module; Figure 4 This is a flowchart illustrating the workflow of the main control module. Detailed Implementation

[0020] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0022] Example 1; like Figure 1 As shown, this application provides a photoelectric and electromagnetic composite force balance control system, the system comprising: The differential photoelectric detection module includes a light-emitting unit, a photosensitive unit, and a differential amplification unit symmetrically arranged on both sides of the movable part. The differential amplification unit is connected to the photosensitive unit and is configured to convert the differential current signal output by the photosensitive unit into a voltage signal and eliminate common-mode interference. The displacement-to-voltage conversion module, connected to the differential amplifier unit, linearly maps the voltage signal into displacement deviation voltage using an adjustable resistor network. The PID control module includes an analog PID circuit composed of an operational amplifier and an RC network. The input terminal of the analog PID circuit is connected to the displacement deviation voltage and configured to output an electromagnetic force compensation voltage that corresponds to the dynamic response of the displacement deviation in real time. The electromagnetic force actuation module includes a current drive circuit connected to the output of the PID control module, and is configured based on a symmetrically wound compensation coil to generate a reverse balancing force according to the electromagnetic force compensation voltage. The main control module is configured to provide synchronous modulation timing to the light-emitting unit and to provide phase-synchronized first and second triangular waves to the dual-channel PWM modulation module. The dual-channel PWM modulation module includes a first comparator and a second comparator. The first comparator compares the electromagnetic force compensation voltage with a first triangular wave and outputs a PWMW external force signal representing the external force. The second comparator compares the temperature sensor signal with a second triangular wave and outputs a temperature-compensated PWMT temperature signal.

[0023] Specifically, firstly, to detect the displacement deviation of the movable parts, the system employs a differential photoelectric detection module. This module consists of light-emitting units and photosensitive units symmetrically arranged on both sides of the movable part. The light-emitting units generate highly stable light signals using modular LED light sources. These signals are reflected to the photosensitive units, which utilize high-sensitivity photodiodes to accurately detect changes in light intensity and output precise differential current signals. Through this symmetrical layout design, the differential photoelectric detection module effectively eliminates ambient light interference, thereby improving the signal quality output by the photosensitive units. To suppress common-mode interference introduced by environmental factors, the system incorporates a differential amplification unit. This unit precisely adjusts the differential current signal of the photodiodes... The differential amplifier unit converts the voltage signal from the differential amplifier unit into a voltage signal related to the displacement deviation. To achieve higher signal processing accuracy, a high input impedance operational amplifier is used, and an independently shielded signal path is designed to ensure the stability and anti-interference capability of the differential signal. The core of the differential amplifier unit lies in its internal coupling resistor network, which can dynamically adjust the gain to adapt to various application scenarios. In order to further correlate the displacement deviation voltage with the control system, a displacement voltage conversion module is set up in the system. The displacement voltage conversion module linearly maps the voltage signal delivered by the differential amplifier unit into the displacement deviation voltage through an adjustable resistor network. The adjustable resistor network consists of graded precision resistors and is dynamically adjusted by an electric slider adjuster to ensure the linearity and high accuracy of the mapping relationship.Furthermore, the displacement-voltage conversion module can set the proportional coefficient according to specific application scenarios to meet different displacement sensitivity requirements, thereby ensuring system adaptability. For dynamic adjustment of electromagnetic force, the system performs real-time calculation and control through a PID control module. The PID control module consists of an operational amplifier and an RC network forming a traditional analog PID circuit, with its input directly connected to the displacement deviation voltage. In the preferred configuration, the proportional parameter is adjusted by a multi-stage resistor network to optimize system stiffness; the integral parameter is set through a capacitor network to set the integral response time, ensuring system adjustment stability; the differential parameter is used for speed response optimization of electromagnetic compensation to prevent oscillations caused by rapid movement of movable parts. The PID control is achieved by outputting the electromagnetic force compensation voltage in real time. The module can dynamically respond to displacement changes of movable parts, exhibiting not only superior steady-state response performance but also effective suppression of transient external force interference. The core of the electromagnetic force execution module lies in the design of the compensation electromagnetic coil. The compensation coil employs a symmetrical winding method to achieve magnetic field balance, combined with a high-precision current drive circuit. This, in turn, generates a reverse balancing force based on the electromagnetic force compensation voltage output by the PID control module. In the preferred design, the current drive circuit is controlled by an integrated full-bridge driver chip, enabling precise bidirectional adjustment of the current flow direction, ensuring the response speed and stability of the electromagnetic compensation. The system design optimizes the number of coil turns and electromagnetic field strength of the compensation coil to provide stable output within the maximum displacement range for force balance control. In the system's core... In the control unit, the main control module uses synchronous modulation timing based on photoelectric detection. It generates phase-synchronized first and second triangular wave signals to provide a reference signal for the dual-channel PWM modulation module. Simultaneously, the main control module dynamically analyzes the temperature signal and, combined with external force detection data, dynamically compensates for the triangular wave amplitude and the output voltage of the electromagnetic coil. Through an integrated time allocation algorithm, the main control module avoids signal conflicts when coordinating temperature sensing and displacement signal detection, ensuring data accuracy. Finally, the system is equipped with a dual-channel PWM modulation module. A first comparator and a second comparator process the electromagnetic force compensation voltage and the temperature sensor signal, respectively. In the preferred embodiment, the first comparator compares the electromagnetic force compensation voltage with the triangular wave amplitude and the temperature sensor signal. A PWMW signal is generated by comparing the angular wave reference signal to represent and compensate for external forces in real time. The second comparator generates a PWMT signal based on temperature changes to adjust the temperature compensation parameters, ensuring that the system can maintain accurate sensing and response to displacement deviations even in complex external environments. In summary, in this preferred embodiment, through the refined design and optimization of the differential photoelectric detection module, differential amplification unit, displacement voltage conversion module, PID adjustment module, electromagnetic force execution module, main control module, and dual-channel PWM modulation module, the system effectively achieves dynamic control of the balance between photoelectric and electromagnetic composite forces. Furthermore, this preferred embodiment can adapt to different application scenarios, such as high-precision displacement detection equipment or ultrasensitive force balance experimental instruments.

[0024] The technical solution of this invention effectively solves the problem of deteriorated control accuracy caused by electromagnetic coil temperature drift and signal crosstalk in high-precision force balance detection systems, and eliminates the need for AD conversion.

[0025] Furthermore, such as Figure 2 As shown, the PID control module includes: The proportional control unit receives the displacement deviation voltage at its input terminal. The integral control unit has its input terminal connected to the output terminal of the proportional control unit and is used to process the residual error signal output by the proportional control unit. The differential control unit has its input connected to the output of the displacement detection module and is used to detect changes in the speed of the moving parts. An error amplifier is used, with its inverting input connected to the outputs of the proportional control unit, integral control unit, and derivative control unit, respectively, to synthesize a PID control signal. The input terminals of the proportional control unit, integral control unit, and derivative control unit can be configured to be simultaneously connected to the displacement detection module, forming a parallel topology.

[0026] As a preferred embodiment of the above embodiments, in order to achieve precise control of displacement deviation, the proportional control unit of the PID adjustment module is designed to receive the displacement deviation voltage and provide a linear proportional adjustment signal output. In this preferred embodiment, the proportional control unit includes a multi-stage constant-precision resistor network to dynamically adjust the proportional gain coefficient. The setting of the proportional gain directly affects the system stiffness. To ensure stable performance, the output signal is processed by a buffer amplifier to prevent gain jitter caused by load changes. Simultaneously, the proportional control unit optimizes the resistor network layout, effectively reducing errors caused by external noise, thereby avoiding over-adjustment or oscillation due to large displacements of moving parts. The integral control unit works in conjunction with the proportional control unit. The input terminal is connected to the output terminal of the proportional control unit to process the residual error in the proportional output signal. In a preferred embodiment, the integral control unit employs a combination of an integral operational amplifier and a high-precision integral capacitor. The integral capacitor is designed with a fixed capacitance value, but allows for parallel connection via an external fine-tuning capacitor to adapt to the integral time response requirements of different application scenarios. In specific implementations, to prevent saturation caused by long-term integration, the integral control unit also includes a limiting circuit directly connected in parallel across the integral capacitor. This limiting circuit dynamically suppresses voltage saturation through a fast response mechanism. This design ensures that the system maintains a good integral response during multiple displacement balance adjustments, unaffected by signal accumulation interference from external forces. Differential control... The control unit is used to detect changes in the motion speed of movable parts. Its input is directly connected to the output of the displacement detection module. The differential control unit is designed based on a differential operational amplifier, with a differential capacitor connected in series at its input. A low-capacitance compensation resistor connected in parallel with the capacitor corrects the dynamic response speed. Preferably, a high-performance film capacitor is selected as the differential capacitor to ensure stable impedance characteristics during high-frequency signal operation. At the same time, a phase compensation network is designed at the amplifier output of the differential control unit to compensate for oscillation signals that may be caused by mechanical resonant frequency points, ensuring the detection accuracy of rapid motion of movable parts by differential control, while avoiding feedback loop disorder. The error amplifier is responsible for transmitting the signals from the proportional control unit and the integral control unit. The output signal of the differential control unit is processed together to synthesize the final PID control signal. In the preferred embodiment, the error amplifier adopts a precision dual operational amplifier architecture. Its inverting input terminal is designed as multiple independent signal input channels to avoid the decrease in control accuracy caused by signal aliasing. The output terminal of the error amplifier is directly connected to the electromagnetic force execution module to drive the compensation electromagnetic coil to generate a reverse balancing force. In the specific implementation, the internal feedback network design of the error amplifier allows the weight of the response to different sensor signals to be adjusted according to the actual application scenario. By optimizing the resistance distribution of the feedback network, the system can achieve a fast response to external forces in a dynamic equilibrium state, and at the same time generate an electromagnetic force compensation voltage with fast oscillation suppression for displacement deviation.In summary, the PID control module design, through the tight coupling of proportional, integral, and derivative control units and the error amplifier, forms a complete dynamic closed-loop control. In the preferred embodiment, to achieve more efficient control performance, each unit in the module has optimized the structural layout of its internal components and is equipped with additional protection circuits to ensure operational stability. For example, the multi-level network design of the proportional control unit effectively improves system stiffness, the limiting circuit of the integral control unit prevents saturation, and the phase network of the derivative control unit avoids resonant point interference. Through the combination and improvement of these technologies, the PID control module can output a precise response signal in real time, thereby supporting the system's response to displacement deviations. This implementation offers rapid adjustment and stability recovery, making it particularly suitable for high-precision force balance experimental equipment or ultra-low error displacement control scenarios. The input terminals of the proportional control unit, integral control unit, and derivative control unit are simultaneously connected to the output signal interface of the displacement detection module. Compared to a series structure, the parallel topology can directly acquire the complete output signal without relying on the output of other control units. This design allows each unit to operate independently during signal processing without interference. For example, when the displacement detection module generates a composite signal including low-frequency background drift and high-frequency vibration disturbance components, each unit can process different signal characteristics separately within the same timeframe, resulting in faster overall processing speed. Furthermore, it is more efficient. In the parallel structure, different control units play their respective roles based on the different characteristics of the input signal: the proportional control unit directly receives the input signal from the displacement detection module and quickly processes transient deviations; the output signal of the proportional unit directly participates in the generation of the PID composite signal in the form of steady-state gain. The integral control unit simultaneously receives the input signal and only accumulates and calculates the long-term residual error signal to correct the deviation. However, the independent operation of the integral unit avoids the erroneous coupling that may be caused by the dynamic changes of the proportional unit signal. The derivative control unit focuses on detecting the velocity change of the input signal and processes the high-frequency signal components to suppress sudden disturbances. This unit directly converts the derivative response... The output should be transmitted to the PID control module to establish transient control performance. The parallel layout allows the output signals of the proportional control unit, integral control unit, and derivative control unit to be simultaneously sent to the error amplifier for real-time synthesis. The error amplifier integrates the three input signals to generate a precise PID control signal. The amplifier contains a weighted feedback network, which allows the signal weights of the three units to be dynamically adjusted according to system requirements, improving the adaptability of the control system. For example, in high-frequency disturbance scenarios, the main control module can increase the weight of the derivative control unit signal, while in steady-state operation, more emphasis is placed on the response of the integral unit. Therefore, the weight allocation optimization corresponding to different control objectives is applied in this structure.The greatest advantage of parallel topology lies in its simultaneous signal processing capability, avoiding the delay problem caused by signal reliance on multi-stage transmission in series structures. Simultaneously, this design allows the proportional, integral, and derivative functions to be independent, enabling different units to adjust parameters according to actual needs to meet control requirements under complex external interference scenarios. Furthermore, the error amplifier, by integrating the parallel signals, ensures that the PID control signal output by the entire system has higher overall accuracy, further improving overall response capability and stability.

[0027] Furthermore, the proportional control unit includes: A multi-stage adjustable resistor network is used to set the system stiffness coefficient; The first-stage buffer amplifier is connected to the input of a multi-stage adjustable resistor network; The second-stage buffer amplifier is connected to the output of the multi-stage adjustable resistor network; The resistance value of the multi-stage adjustable resistor network is configured to suppress overshoot oscillation of the moving parts.

[0028] As a preferred embodiment of the above, the core of the proportional control unit lies in its multi-level adjustable resistor network design. This multi-level adjustable resistor network is used to precisely set the system's stiffness coefficient, thereby effectively stabilizing the feedback adjustment of displacement deviation. In a preferred embodiment, the multi-level adjustable resistor network includes multiple precision resistors, which are dynamically adjusted by rotating an electrically adjustable resistor. This resistor arrangement forms a wide-range gain control grid, enabling progressively fine-tuning of resistance values ​​to adapt to different force balance requirements and displacement adjustment scenarios. By selecting appropriate resistance values, the system stiffness coefficient can quickly respond to and adapt to changes in external force, ensuring that rapid system balance adjustment does not trigger additional oscillations. Or amplitude variation; to ensure stable signal transmission, the proportional control unit incorporates a first-stage buffer amplifier at the input of the multi-stage adjustable resistor network. Preferably, the first-stage buffer amplifier uses a low-noise operational amplifier to improve the processing accuracy of the input signal and prevent servo effects caused by resistance changes during transmission. This design, by buffering the input signal, prevents additional disturbances to the original signal when the resistor network is connected, thus ensuring the stability and accuracy of the system during signal reception. At the output of the multi-stage adjustable resistor network, a second-stage buffer amplifier further optimizes signal stability. The second-stage buffer amplifier employs a wide dynamic range... The high-performance amplifier chip design ensures that dynamic changes in the resistor network do not cause abrupt changes in signal amplitude or phase during signal transmission. This resistance adjustment effectively suppresses overshoot oscillations of moving parts. The second-stage buffer amplifier stabilizes the output signal and maintains linearity during retransmission, ensuring the final output proportional control signal has good adaptability to unpredictable external force changes. To further understand the technical effects of this preferred solution, consider this example: in a scenario requiring real-time displacement adjustment and balance maintenance, the system can flexibly adjust multiple resistor stages to cope with external disturbances. Simultaneously, to ensure stability even under complex conditions... Under mixed force conditions, the signal adjustment of the proportional control unit still stably participates in the feedback loop of PID regulation. The combined design of each stage of resistor adjustment and buffer amplification enables the system to quickly adjust the feedback in a short time, thereby avoiding transient overshoot or oscillation caused by inertia. In summary, this specific embodiment optimizes the performance of the proportional control unit in dynamically adjusting the system stiffness coefficient and suppressing overshoot oscillation through the integrated design of multi-stage adjustable resistor networks and buffer amplifiers. Through the close coordination between these components and the precise control of the dynamic characteristics of the resistor network, the system can stably perform displacement feedback control without over-adjustment due to load changes.

[0029] Furthermore, the integral control unit includes: The integrating operational amplifier has its non-inverting input terminal grounded. The integrating capacitor is connected between the inverting input and the inverting output of the integrating operational amplifier. A limiting circuit, connected in parallel across the integrating capacitor, is used to prevent integral saturation. The capacitance value of the integrating capacitor is configured such that the integration time constant of the integrating capacitor is greater than the maximum reset period of the movable part.

[0030] In a preferred embodiment, the core of the integral control unit is an integral operational amplifier. Its non-inverting input is grounded to stabilize the signal reference point, and its inverting input receives the residual error signal from the proportional control unit. This design not only reduces the impact of system noise on the error signal but also improves signal processing sensitivity through the amplifier's high input impedance. Preferably, the integral operational amplifier uses a low-noise, wideband operational amplifier to ensure stable dynamic response even under high-frequency signal conditions, thus meeting the speed and accuracy requirements for signal processing in complex force balance scenarios. The integral capacitor is a key component in the integral operational amplifier that realizes the signal integration function. Its inverting input is connected to the inverting output of the operational amplifier and is used to accumulate the input. The residual error signal is processed to generate an integral output. In the preferred embodiment, the capacitance value of the integrating capacitor is optimized experimentally to ensure that the integration time constant is always greater than the maximum reset period of the movable part. This ensures that the integral control unit has a response delay tolerance capability to the error signal. The integrating capacitor uses a high-reliability electrolytic capacitor or ceramic capacitor to improve the stability of signal integration and the reliability of long-term operation. In addition, to cope with high dynamic load scenarios, the capacitance value can be adjusted through an external fine-tuning capacitor network, thereby further improving the system's adaptability to different force balance scenarios. The limiting circuit is connected in parallel across the integrating capacitor and forms a closed-loop working state with the integrating operational amplifier, effectively overcoming the system failure that may be caused by integral saturation. In the preferred embodiment, the limiting circuit... The circuit employs a bidirectional clamping protection mechanism, which dynamically limits the maximum and minimum values ​​of the voltage across the integrating capacitor. Specifically, the built-in semiconductor devices in the limiting circuit exhibit fast response characteristics, enabling them to quickly cut off excessive voltage inputs, thus keeping the output voltage of the integrating capacitor within its linear operating range. This mechanism not only ensures the stable operation of the integrating control unit during long-term operation but also prevents system failure caused by transient external force interference. To further illustrate the practical effect of this technical solution, an application example can be used: In a photoelectric and electromagnetic combined force balance experiment, if frequent fluctuations in the applied force lead to continuous accumulation of error signals, the traditional integrating control unit may saturate due to insufficient limiting, producing erroneous filtering results and affecting the system. The feedback loop causes negative effects, but this preferred solution, through the design of dynamically configured integrating capacitors and fast-response limiting circuits, enables the integral control unit to limit the growth of errors before they accumulate to a critical value. Furthermore, the dynamic response rate is further optimized through the integral time constant, allowing the feedback system to maintain stable operation under rapidly changing external force conditions. In summary, this specific implementation improves the accuracy and stability of the integral control unit in processing residual error signals through the coordinated design and optimization of the integrating operational amplifier, integrating capacitor, and limiting circuit. It also solves the integral saturation problem and ensures that its integral time constant meets the requirements of the system reset cycle. This preferred solution is particularly suitable for high dynamic response scenarios and force balance experimental equipment requiring high precision.

[0031] Furthermore, the differential control unit includes: A differential operational amplifier whose inverting input receives displacement detection signals through a differential capacitor; A compensation resistor is connected in parallel across the differential capacitor; A phase compensation network is connected to the output of the differential operational amplifier; The capacitance value of the differential capacitor is configured to attenuate the oscillation at the mechanical resonant frequency of the movable part.

[0032] In a preferred embodiment, the core component of the differential control unit is a differential operational amplifier. Its inverting input receives signals from the displacement detection module via a differential capacitor and amplifies the velocity component in the signal. In a preferred embodiment, the differential operational amplifier is selected from operational amplifier chips with wide bandwidth and high gain to ensure it can adapt to complex signal changes and provide high-precision amplification in high dynamic response scenarios. To optimize device performance, the amplifier's input uses a shielded design to effectively reduce noise interference, thereby enabling the received displacement signal to be accurately distinguished as a dynamic velocity change component. The differential capacitor is the core of differential signal processing, connected to... Located between the inverting input and output of the differential operational amplifier, it is responsible for rapidly responding to the velocity change component of the input displacement detection signal. In a preferred embodiment, the differential capacitor is a high-quality thin-film capacitor, whose capacitance value is precisely calculated to adapt to the attenuation requirements at the mechanical resonant frequency in different scenarios. For example, in applications with a wide frequency response range, the capacitance value can be appropriately reduced to enhance the response speed; while in scenarios where the mechanical resonant frequency is prone to generating high-amplitude oscillations, the capacitance value is increased to ensure effective signal attenuation. Dynamic configuration of the capacitance value can be achieved through parallel connection of external capacitors, thus enabling the differential capacitor's characteristics to meet the needs of various system operations. To further optimize the dynamic performance of the differential capacitor, this embodiment connects a compensation resistor in parallel across the capacitor. The compensation resistor stabilizes signal transmission and simultaneously suppresses mechanical oscillation signals through dynamic attenuation. Preferably, the compensation resistor is selected as a high-heat-resistant, low-capacitance resistor to reduce signal transmission losses. The specific resistance value of the compensation resistor is adjusted according to the system's operating characteristics to ensure a complete match with the differential capacitor, thereby further canceling out the mechanical resonant frequency signal. This significantly improves the system's stability during speed change sensing. This design effectively solves the problems inherent in traditional differential networks in suppressing mechanical oscillations. The signal transition problem is addressed by connecting the output of the differential control unit to a phase compensation network. This network is used to repair signal phase distortion caused by mechanical resonant frequency points. In a preferred embodiment, a high-precision phase compensation structure composed of capacitors, inductors, and resistors is designed. By dynamically adjusting the phase response, the signal phase stability during mechanical motion is enhanced. In this scheme, the compensation network characteristics adapt to changes in the external environment to meet the signal correction requirements within different mechanical frequency ranges. Furthermore, the phase compensation network can also take into account the amplitude adjustment of the signal, ensuring that it does not generate additional amplitude shift due to phase correction, thereby guaranteeing a good response of the system in different force balance scenarios.To illustrate the practical effect of the preferred solution, an application example can be used: In vibration testing equipment, when the mechanical resonant frequency of movable parts frequently generates high-amplitude oscillations, traditional differential networks may cause excessive feedback errors due to signal distortion, thereby disrupting the dynamic adjustment of the system's force balance. This implementation significantly reduces the oscillation amplitude at the resonant point by optimizing the capacitance configuration of the differential capacitor and the dynamic attenuation effect of the compensation resistor. Furthermore, through response correction via the phase compensation network, the system maintains a precise response under dynamic control of the oscillation frequency, while ensuring stable signal output.

[0033] Furthermore, such as Figure 3 As shown, the displacement-voltage conversion module includes: A photodiode configured to receive light signals reflected from a movable part; A transimpedance amplifier converts the optical signal generated by a photodiode into an initial voltage. A programmable gain amplifier amplifies the initial voltage; The upper limit of the gain of the programmable gain amplifier is dynamically matched with the resistance value of the multi-stage adjustable resistor network in the proportional control unit.

[0034] In a preferred embodiment, the photodiode of the displacement-voltage conversion module receives the light signal reflected from the movable part and processes it in subsequent circuits. Preferably, a high-sensitivity, low-noise type photodiode is selected, with its response wavelength range strictly matched to the emission range of the light-emitting unit to ensure efficient light signal reception. In specific scenarios, the surface of the movable part undergoes a special coating treatment to enhance the consistency of the reflected light signal, thereby improving the strength and stability of the photodiode's input signal. Furthermore, to avoid interference from ambient light, an optical filter window is configured near the photodiode to allow only a specific range of light signals to pass through, further improving the reliability of signal reception. After conversion, the light signal received by the photodiode is used to generate an initial voltage by a transimpedance amplifier. Preferably, the transimpedance amplifier uses a high-performance operational amplifier chip, whose input terminal is connected to the photodiode through a precision resistor, thereby accurately converting the generated photocurrent signal into a linear voltage signal. The transimpedance amplifier is designed with high input impedance and a wide dynamic range, capable of handling light signals with varying amplitudes while ensuring the linearity of the output voltage and noise suppression. In the preferred design, the transimpedance amplifier also reduces environmental electromagnetic interference through a shielding structure. The initial voltage signal is stably input to the next stage circuit. The initial voltage is then input to a programmable gain amplifier for further amplification. In the preferred embodiment, the core of the programmable gain amplifier is an amplification module with dynamically adjustable gain characteristics. Its gain setting can be dynamically adjusted via an external programming terminal to match the resistance values ​​of the multi-stage adjustable resistor network in the proportional control unit. For example, when the stiffness coefficient of the proportional control unit is high, the amplifier automatically sets a lower gain to avoid signal over-amplitude; while when the stiffness coefficient of the proportional control unit is low, the amplifier increases the gain to ensure that the signal amplitude meets the system control requirements. This design improves the overall coordination of the system, enhancing the adaptability of the displacement voltage conversion module to different operating scenarios. The design of the programmable gain amplifier also considers the linear response characteristics of the amplifier. By equipping the gain adjustment terminal with a precision voltage reference module, the adjustment process can achieve a smooth transition without gain jumps, thereby avoiding signal distortion and system control failures caused by rapid gain changes. Furthermore, the maximum value of the gain range is dynamically matched with the resistance values ​​of the multi-stage adjustable resistor network of the proportional control unit. Its specific upper limit is determined through experimental adjustment and calculation to ensure optimal compatibility for signal processing across all resistance ranges.To better illustrate the practical effect of the preferred solution, consider this example: In a complex working environment, the light signal reception intensity on the operating surface of movable parts fluctuates significantly due to environmental changes. Traditional sensing circuits, limited by fixed gain, may be unable to flexibly respond to these changes, leading to control adjustment errors. However, this implementation, through a high-sensitivity photodiode receiving module and a dynamic gain adjustment mechanism of a programmable gain amplifier, ensures that the signal amplitude always matches the operating range of the proportional control unit. Ultimately, the system can operate stably in complex environments and maintain high-precision processing of dynamic signal changes.

[0035] Furthermore, the current drive circuit includes: The full-bridge driver chip has four drive output channels; The gates of the first complementary MOS transistor group are respectively connected to the first drive output channel and the second drive output channel of the full-bridge driver chip. The gates of the second complementary MOS transistor group are respectively connected to the third and fourth drive output channels of the full-bridge driver chip. The full-bridge driver chip is configured such that when the displacement deviation voltage is positive, the first complementary MOS transistor group is enabled to drive the electromagnetic coil in the positive direction; when the displacement deviation voltage is negative, the second complementary MOS transistor group is enabled to drive the electromagnetic coil in the reverse direction; and the first complementary MOS transistor group and the second complementary MOS transistor group are prohibited from being turned on simultaneously.

[0036] As a preferred embodiment, the core of the current drive circuit is a full-bridge driver chip. The full-bridge driver chip is designed with four drive output channels, enabling flexible control of the current flow direction in the electromagnetic coil. Preferably, the full-bridge driver chip adopts a high-reliability chip architecture, integrating power management and output overload protection mechanisms to ensure that the system will not experience drive failures due to current fluctuations during operation. Each drive output channel has an independent current limiting control function. This design not only enhances adaptability to different operating scenarios but also improves the dynamic response balance between output channels. The first complementary MOSFET group is configured under the control of the first and second drive output channels of the full-bridge driver chip. Its design purpose is to ensure that the drive current flows forward through the electromagnetic coil when the displacement deviation voltage is positive. Preferably, the first complementary MOSFET group consists of a pair of complementary MOSFETs, using a low on-resistance model to reduce drive current loss. The gate is connected to the drive channel interface of the full-bridge driver chip, allowing the MOSFET group to be quickly turned on when a positive voltage signal is input, ensuring efficient forward current transmission. To reduce response hysteresis, the second complementary MOSFET group is connected to the third and fourth drive output channels of the full-bridge driver chip. Its function is to drive the current to flow in reverse through the electromagnetic coil when the displacement deviation voltage is negative. In the preferred embodiment, the second complementary MOSFET group also adopts a pair of complementary MOSFETs. By configuring the gate control signal, when a negative voltage signal enters, the system can quickly switch and allow the reverse current flow to realize the reverse force of electromagnetic compensation. Since the first complementary MOSFET group and the second complementary MOSFET group will generate opposite current drive directions, the design explicitly prohibits simultaneous conduction to avoid short circuits in the electromagnetic coil or drive system failure. In addition, to ensure that the current flow through the MOSFET group always runs in the expected direction, an intelligent conduction control module is integrated into the design logic. The intelligent conduction control module has real-time voltage polarity detection and fast switching mechanism. In the preferred embodiment, the intelligent conduction control module can accurately determine which MOSFET group needs to be turned on or off based on voltage changes. During operation, the system will continuously detect the current voltage polarity change to effectively adjust the drive circuit in real time. This synchronous switching further enhances the precision of coefficient control. For example, in a complex mechanical force balance experiment, when an external force is applied and the displacement deviation voltage reverses rapidly, traditional drive circuits may cause compensation errors due to slow response or improper current direction switching. However, this implementation scheme, through the precise combination design of the full-bridge drive chip and complementary MOS transistor group, enables the current to adjust the drive direction in a timely manner according to the polarity change of the displacement deviation voltage, thereby achieving precise electromagnetic force output and ensuring the accuracy and stability of force balance control.

[0037] Furthermore, such as Figure 4 As shown, the main control module is configured to include: Receive the PWMT temperature signal and analyze the duty cycle of the PWMT temperature signal; Calculate the resistance temperature drift coefficient of the electromagnetic coil based on the analyzed duty cycle; The output amplitude of the first triangular wave generator is dynamically adjusted according to the resistance temperature drift coefficient. The electromagnetic coil resistance changes are compensated based on the generator output amplitude to maintain a constant electromagnetic force output.

[0038] As a preferred embodiment of the above, the main control module first receives the PWMT temperature signal through the temperature sensor system, and then analyzes the duty cycle of the signal through a high-precision measurement unit. In the preferred embodiment, the temperature signal processing unit has a built-in high-speed signal processor chip, which has the function of duty cycle measurement and analysis, and can monitor the changes of the PWM signal in real time at the microsecond level. This measurement unit operates efficiently under varying ambient temperatures, ensuring the system can detect subtle temperature changes and make rapid adjustments. The obtained duty cycle is used to further calculate the resistance temperature drift coefficient of the electromagnetic coil. In the preferred embodiment, the calculation unit integrated within the main control module reads the collected temperature data and applies a preset temperature-corresponding resistance change database to determine the specific resistance temperature coefficient. This database, calibrated through multiple experiments and data collection, covers the temperature variation range in actual use. This mechanism allows the main control module to react quickly to changes in the resistance of the electromagnetic coil, providing an accurate basis for subsequent output adjustments. After the resistance temperature drift coefficient is calculated, the main control module needs to dynamically adjust the output amplitude of the first triangular wave generator according to temperature changes. In the preferred design, the triangular wave generator has an automatic gain adjustment function, correcting the output parameters in real time through an internal control chip. The generator can automatically change the output amplitude during signal generation based on the dynamic changes in the temperature drift coefficient to adapt to the current resistance state of the electromagnetic coil. This dynamic adjustment design... This ensures precise and stable electromagnetic force output, maintaining output consistency even when resistance drifts significantly. Finally, the main control module compensates for changes in the electromagnetic coil's resistance based on the adjusted generator output amplitude, ensuring a continuous and constant electromagnetic force output. The preferred approach at this stage utilizes an intelligent feedback loop to achieve power regulation and control optimization, enabling the entire system to monitor and precisely adjust output force changes in real time. This ensures the electromagnetic force remains at the set value in various temperature environments. This strategy not only avoids system misadjustment due to temperature changes but also further enhances the stability and reliability of force balance control in complex environments. For example, in a high-temperature industrial environment, the resistance of the electromagnetic coil may drift significantly due to rapid changes in ambient temperature. If the system lacks a real-time dynamic compensation mechanism, the accuracy of electromagnetic force control may be severely affected. This implementation, through the main control module's temperature analysis and dynamic adjustment functions, allows the system to counteract the effects of such external parameter changes in real time, ensuring the electromagnetic force remains in a stable output state.

[0039] Furthermore, the main control module is also configured to include: Monitor the rising edge of the PWMW external force signal; During the rising edge of the PWMW external force signal, the input signal transmitted to the temperature compensation channel drive circuit is blocked. Capture the peak sampling points of the PWMT temperature signal; During the peak sampling period of the PWMT temperature signal, the acquisition of the displacement signal is paused.

[0040] As a preferred embodiment of the above, firstly, the main control module monitors the PWMW external force signal in real time through the intelligent analysis unit and specifically locates its rising edge trigger point.As the core signal characterizing the amplitude of external force and the dynamic characteristics of response, the processing of the rising edge of the PWMW signal directly affects the response speed and adjustment accuracy of the entire system. Therefore, the main control module uses a high-precision signal comparator to capture the appearance of the rising edge in real time and immediately sends a trigger signal to the back-end logic circuit when a signal transition is detected. In the preferred design, this signal processing unit integrates a high-speed clock link to ensure that the monitoring response time is lower than the minimum period of the signal, thus ensuring that all critical transitions can be accurately captured. After capturing the rising edge of the PWMW external force signal, the main control module temporarily blocks the input signal transmitted to the temperature compensation channel drive circuit to ensure signal independence during the critical adjustment phase. In the preferred embodiment, the switching circuit used to implement the blocking is set at the temperature... The starting point of the temperature compensation channel is linked with the PWMW signal trigger control logic. The signal path of the temperature compensation channel is cut off the instant the main control module captures the rising edge. This design avoids potential resource contention or signal interference between the external force signal adjustment process and the temperature compensation path, providing a clearer channel environment for the subsequent accurate processing of external force signals. On the other hand, the main control module also designs a peak sampling strategy for the temperature signal to identify the maximum signal point of the PWMT temperature signal. The peak sampling point of the temperature signal provides a key time axis reference for analyzing the temperature coefficient of resistance and subsequent compensation. In the preferred method, extreme points are identified by continuously comparing the slope changes of signal segments. As the signal gradually rises, the peak value is identified through real-time slope comparison. Within the near-range, and upon confirmation of a peak sampling point, the sampled signal value and timestamp are recorded simultaneously. This efficient sampling strategy not only quickly finds the accurate peak signal value but also minimizes the occupation of acquisition resources. During the critical period of peak identification, the main control module is also configured with a highly optimized signal coordination mechanism, namely, pausing the acquisition of displacement signals. Since the signal dynamics may be in a high-update state during the short period of peak sampling, pausing acquisition can avoid data channel conflicts and errors caused by asymmetrical signal sampling. In the preferred method, the main control module sends an interrupt command at the same time as the peak event of the PWMT temperature signal is registered through signal-driven logic, causing it to pause the acquisition and processing of displacement signals. This operation avoids affecting the accurate sampling of the temperature signal. This ensures the independent sampling accuracy of the two types of signals and the overall coordination of the system. To further illustrate the practical application effect of this implementation method, the following example is given: Suppose that in a complex production environment, due to drastic temperature fluctuations and frequent mechanical vibrations, both the PWMW external force signal and the PWMT temperature signal may change drastically at the same time. In traditional designs, limited signal channel resources result in poor synchronization between temperature adjustment and external force measurement, and the overall system performance will show significant lag or even interference. This implementation method achieves dynamic optimization allocation of signal resources by quickly blocking the temperature channel at the rising edge of the PWMW and accurately intercepting the sampling peak of the PWMT, thereby ensuring that both types of signals can be efficiently and accurately acquired and processed within the controllable range of the system.

[0041] Example 2; Based on the same inventive concept as the photoelectric and electromagnetic composite force balance control system described in the foregoing embodiments, the present invention also provides a photoelectric and electromagnetic composite force balance control method, the method comprising: Synchronous modulated light is emitted by the light-emitting units on both sides of the movable part. The photosensitive unit receives the differential light signal reflected by the movable part and generates a differential current signal. The differential current signal is then converted into an initial voltage signal based on the differential amplification unit. The initial voltage signal is input into an adjustable resistor network for linear mapping, and the displacement deviation voltage is output. The displacement deviation voltage is input into an analog PID circuit to generate an electromagnetic force compensation voltage. According to the polarity of the electromagnetic force compensation voltage, the full-bridge driver chip is controlled to enable the first complementary MOS transistor group or the second complementary MOS transistor group, and the driving current flows in the forward or reverse direction through the symmetrically wound compensation coil to generate a reverse balancing force. The electromagnetic force compensation voltage is compared with the first triangular wave provided by the main control module to output the PWMW external force signal, and the temperature sensor signal is compared with the second triangular wave provided by the main control module to output the PWMT temperature signal. The main control module analyzes the duty cycle of the PWMT temperature signal to calculate the resistance temperature drift coefficient of the electromagnetic coil and dynamically adjusts the amplitude of the first triangular wave to compensate for the electromagnetic force output. The drive signal of the temperature compensation channel is blocked during the rising edge of the PWMW external force signal, and the acquisition operation of the displacement signal is paused during the peak sampling period of the PWMT temperature signal.

[0042] The method described above in this invention can effectively realize a photoelectric and electromagnetic composite force balance control system, and the technical effects it can achieve are as described in the above embodiments, which will not be repeated here.

[0043] Although this application has been described in conjunction with specific features and embodiments, it is obvious that various modifications and combinations can be made thereto without departing from the spirit and scope of this application. Accordingly, this specification and drawings are merely exemplary illustrations of the application as defined herein, and are to be considered as covering any and all modifications, variations, combinations, or equivalents within the scope of this application. Clearly, those skilled in the art can make various alterations and modifications to this application without departing from its scope. Thus, if such modifications and modifications fall within the scope of this application and its equivalents, this application intends to include such modifications and modifications.

Claims

1. A photoelectric and electromagnetic composite force balance control system, characterized in that, The system includes: A differential photoelectric detection module includes a light-emitting unit, a photosensitive unit, and a differential amplification unit symmetrically arranged on both sides of a movable part. The differential amplification unit is connected to the photosensitive unit and is configured to convert the differential current signal output by the photosensitive unit into a voltage signal and eliminate common-mode interference. The displacement-voltage conversion module is connected to the differential amplifier unit and linearly maps the voltage signal into a displacement deviation voltage according to the adjustable resistor network. The PID control module includes an analog PID circuit composed of an operational amplifier and an RC network. The input terminal of the analog PID circuit is connected to the displacement deviation voltage and configured to output an electromagnetic force compensation voltage that corresponds to the dynamic response of the displacement deviation in real time. The electromagnetic force actuation module includes a current drive circuit connected to the output terminal of the PID regulation module, and is configured based on a symmetrically wound compensation coil to generate a reverse balancing force according to the electromagnetic force compensation voltage. The main control module is configured to provide synchronous modulation timing to the light-emitting unit and to provide phase-synchronized first and second triangular waves to the dual-channel PWM modulation module. The dual-channel PWM modulation module includes a first comparator and a second comparator. The first comparator compares the electromagnetic force compensation voltage with the first triangular wave and outputs a PWMW external force signal representing the external force. The second comparator compares the temperature sensor signal with the second triangular wave and outputs a temperature-compensated PWMT temperature signal. The main control module is configured to include: Receive the PWMT temperature signal and analyze the duty cycle of the PWMT temperature signal; Calculate the resistance temperature drift coefficient of the electromagnetic coil based on the duty cycle described in the analysis; The output amplitude of the first triangular wave generator is dynamically adjusted according to the resistance temperature drift coefficient. The resistance change of the electromagnetic coil is compensated according to the output amplitude of the generator to maintain a constant electromagnetic force output; The main control module is further configured to include: Monitor the rising edge of the PWMW external force signal; During the rising edge of the PWMW external force signal, the input signal transmitted to the temperature compensation channel drive circuit is blocked. Capture the peak sampling points of the PWMT temperature signal; During the peak sampling period of the PWMT temperature signal, the acquisition of the displacement signal is paused.

2. The photoelectric and electromagnetic composite force balance control system according to claim 1, characterized in that, The PID control module includes: A proportional control unit, wherein the input terminal of the proportional control unit receives the displacement deviation voltage; An integral control unit, the input of which is connected to the output of the proportional control unit, is used to process the residual error signal output by the proportional control unit; A differential control unit, the input of which is connected to the output of the displacement detection module, is used to detect changes in the motion speed of the movable part; An error amplifier is provided, the inverting input of which is connected to the outputs of the proportional control unit, the integral control unit, and the derivative control unit, respectively, to synthesize a PID control signal. The input terminals of the proportional control unit, the integral control unit, and the derivative control unit can be configured to be simultaneously connected to the displacement detection module, forming a parallel topology.

3. The photoelectric and electromagnetic composite force balance control system according to claim 2, characterized in that, The proportional control unit includes: A multi-stage adjustable resistor network is used to set the system stiffness coefficient; The first-stage buffer amplifier is connected to the input terminal of the multi-stage adjustable resistor network; The second-stage buffer amplifier is connected to the output of the multi-stage adjustable resistor network. The resistance value of the multi-stage adjustable resistor network is configured to suppress overshoot oscillation of the movable component.

4. The photoelectric and electromagnetic composite force balance control system according to claim 2, characterized in that, The integral control unit includes: An integrating operational amplifier, wherein the non-inverting input terminal of the integrating operational amplifier is grounded; An integrating capacitor is connected between the inverting input terminal and the inverting output terminal of the integrating operational amplifier. A limiting circuit is connected in parallel across the integrating capacitor to prevent integral saturation. The capacitance value of the integrating capacitor is configured such that the integration time constant of the integrating capacitor is greater than the maximum reset period of the movable part.

5. The photoelectric and electromagnetic composite force balance control system according to claim 2, characterized in that, The differential control unit includes: A differential operational amplifier whose inverting input receives displacement detection signals through a differential capacitor; A compensation resistor is connected in parallel across the differential capacitor; A phase compensation network is connected to the output of the differential operational amplifier; The capacitance value of the differential capacitor is configured to attenuate the oscillation at the mechanical resonant frequency of the movable component.

6. The photoelectric and electromagnetic composite force balance control system according to claim 1, characterized in that, The displacement-voltage conversion module includes: A photodiode configured to receive light signals reflected by the movable component; A transimpedance amplifier converts the optical signal generated by the photodiode into an initial voltage. A programmable gain amplifier amplifies the initial voltage; The upper limit of the gain of the programmable gain amplifier is dynamically matched with the resistance value of the multi-stage adjustable resistor network in the proportional control unit.

7. The photoelectric and electromagnetic composite force balance control system according to claim 1, characterized in that, The current driving circuit includes: The full-bridge driver chip has four drive output channels; The first complementary MOS transistor group has its gates connected to the first drive output channel and the second drive output channel of the full-bridge driver chip, respectively. The gates of the second complementary MOS transistor group are respectively connected to the third and fourth drive output channels of the full-bridge driver chip. The full-bridge driver chip is configured to enable the first complementary MOS transistor group to drive the electromagnetic coil in the positive direction when the displacement deviation voltage is positive; and to enable the second complementary MOS transistor group to drive the electromagnetic coil in the reverse direction when the displacement deviation voltage is negative; and the first complementary MOS transistor group and the second complementary MOS transistor group are prohibited from being turned on simultaneously.

8. A method for balancing photoelectric and electromagnetic composite forces, characterized in that, The method employing the photoelectric and electromagnetic composite force balance control system as described in claim 1 includes: Synchronous modulated light is emitted by the light-emitting units on both sides of the movable part. The photosensitive unit receives the differential light signal reflected by the movable part and generates a differential current signal. The differential current signal is then converted into an initial voltage signal based on the differential amplification unit. The initial voltage signal is input into an adjustable resistor network for linear mapping, and the displacement deviation voltage is output. The displacement deviation voltage is input into an analog PID circuit to generate an electromagnetic force compensation voltage. According to the polarity of the electromagnetic force compensation voltage, the full-bridge driver chip is controlled to enable the first complementary MOS transistor group or the second complementary MOS transistor group, and the driving current flows in the forward or reverse direction through the symmetrically wound compensation coil to generate a reverse balancing force. The electromagnetic force compensation voltage is compared with the first triangular wave provided by the main control module to output the PWMW external force signal, and the temperature sensor signal is compared with the second triangular wave provided by the main control module to output the PWMT temperature signal. The main control module analyzes the duty cycle of the PWMT temperature signal to calculate the resistance temperature drift coefficient of the electromagnetic coil and dynamically adjusts the amplitude of the first triangular wave to compensate for the electromagnetic force output. The drive signal of the temperature compensation channel is blocked during the rising edge of the PWMW external force signal, and the acquisition operation of the displacement signal is paused during the peak sampling period of the PWMT temperature signal.

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