Medical cold light source control system and method

Abstract

The invention relates to a medical cold light source control system and method, and relates to the technical field of medical light source control, and the system comprises an LED light source module, a temperature sensor, a driving circuit and a control unit. The control method comprises the following steps: querying a preset model through the feedforward control module according to a target brightness instruction, and quickly calculating a basic driving instruction; meanwhile, a gain scheduling module predicts thermal disturbance according to the brightness change and dynamically adjusts and generates a working PID (Proportion Integration Differentiation) gain; and the feedback control module calculates a feedback correction instruction according to the deviation between the actual temperature and the target temperature by using the working PID gain. And finally, the instruction synthesis module synthesizes the basic driving instruction and the feedback correction instruction into a composite driving instruction, and controls a driving circuit to drive a light source. Fast response is guaranteed through feedforward, and smoothness of the dynamic adjusting process and final temperature stability are guaranteed through feedback of self-adaptive gain.

Description

Technical Field

[0001] The present application relates to the field of medical light source control technology, and in particular to a medical cold light source control system and method. Background Art

[0002] Medical cold light sources, particularly those based on light-emitting diodes (LEDs), are widely used in endoscope illumination, surgical microscope illumination, and various medical examination equipment due to their advantages such as long life, narrow spectral range, low heat generation, and ease of precise control. In these applications, precise, rapid, and stable control of the light source's output optical properties, such as brightness and color temperature, is a key technical requirement for ensuring smooth medical diagnosis and treatment.

[0003] To achieve precise control of LED light sources, existing technologies typically employ closed-loop feedback control systems based on temperature or light intensity, such as proportional-integral-derivative (PID) controllers. However, these control schemes still have inherent limitations in practical applications.

[0004] First, pure feedback control systems have an inherent lag in response speed. Their control logic relies on detecting and compensating for output errors. This means the controller cannot initiate adjustments until a deviation occurs between the actual output and the target setpoint. This process results in the system being unable to respond instantaneously to user commands when large brightness adjustments are required, resulting in a significant response delay, which impacts the immediacy and smoothness of medical operations.

[0005] Secondly, the optoelectronic properties of LED light sources are highly sensitive to their core junction temperature. Current changes and environmental factors during operation can cause junction temperature fluctuations, which in turn can cause drift in luminous flux and color spectrum. While simple feedback control can suppress system disturbances caused by factors such as thermal effects, its regulation is passive and constantly tracks errors, making it difficult to completely and promptly eliminate disturbances when they occur. This can lead to slight fluctuations in output brightness and color temperature under specific operating conditions, affecting the ultimate accuracy and stability of control.

[0006] Furthermore, existing technologies exhibit suboptimal dynamic performance when dealing with large brightness changes. A fixed set of PID parameters is typically a compromise optimized for a specific operating point. When a system faces large step changes in brightness, these fixed control parameters struggle to achieve both rapidity and stability. Aggressive parameters designed for faster response can easily lead to significant temperature overshoot and oscillation during the adjustment process; conservative parameters designed to ensure stability can sacrifice response time. The non-adaptive nature of these control parameters limits the smoothness of the system's dynamic adjustment process. Summary of the Invention

[0007] The purpose of this application is to provide a medical cold light source control system and method, which solves the technical problem of the difficulty in balancing response speed and dynamic adjustment stability in the existing medical cold light source control technology.

[0008] In a first aspect, the present application provides a medical cold light source control system, comprising: LED light source module; a temperature sensor thermally coupled to the LED light source module, for obtaining an actual temperature of the LED light source module; A driving circuit, electrically connected to the LED light source module; a feedforward control module configured to calculate a basic driving instruction based on a received target brightness instruction; a gain scheduling module configured to predict a predicted thermal disturbance of the light source according to a change in the target brightness command, and adjust a set of basic PID gains based on the predicted thermal disturbance to generate an operating PID gain; a feedback control module configured to calculate a feedback correction instruction based on a deviation between the actual temperature obtained by the temperature sensor and a preset target temperature and using the working PID gain; The instruction synthesis module is configured to synthesize the basic driving instruction and the feedback correction instruction to generate a composite driving instruction, and use the composite driving instruction to control the driving circuit.

[0009] In one embodiment, the feedforward control module has a built-in nonlinear mapping model established through offline calibration, which describes the corresponding relationship between the target brightness instruction and the basic driving instruction.

[0010] In one embodiment, the gain scheduling module calculates the predicted thermal disturbance by a thermal characteristic function, wherein the thermal characteristic function represents the relationship between the brightness change of the light source and the temperature change. gain Generate the working PID gain (K ′ p ,K i ′ ,K ′ d ), which is calculated as: (K ′ p ,K i ′ ,K ′ d )=f gain (ΔT pred ,K p ,K i ,Kd ); Among them, (K ′ p ,K i ′ ,K ′ d ) is the working PID gain, f gain is the scheduling function, ΔT pred To predict thermal disturbances, (K p ,K i ,K d ) is the basic PID gain.

[0011] In one embodiment, the feedback control module is configured to execute a PID control algorithm and calculate the feedback correction instruction u using the working PID gain by the following formula: fb (t): Among them, u fb (t) is the feedback correction instruction, e T (t) is the deviation between the preset target temperature and the actual temperature, K ′ p ,K i ′ ,K ′ d is the working PID gain.

[0012] In one embodiment, the instruction synthesis module generates the composite drive instruction u by the following formula: final (t):u final (t) = C ff +u fb (t); Among them, u final (t) is the compound drive instruction, C ff Is the basic driving instruction, u fb (t) is the feedback correction instruction.

[0013] In one embodiment, the control unit is implemented by a digital signal processor (DSP), and the driving circuit generates a pulse width modulation (PWM) signal according to the composite driving instruction to drive the LED light source module.

[0014] In a second aspect, the present application provides a method for controlling a medical cold light source, comprising the following steps: Step S1: receiving a target brightness instruction, and calculating a basic driving instruction based on the target brightness instruction; Step S2: predicting the predicted thermal disturbance of the light source according to the change of the target brightness command, and adjusting a set of basic PID gains based on the predicted thermal disturbance to generate working PID gains; Step S3: acquiring the actual temperature of the LED light source module in real time, and calculating a feedback correction instruction based on the deviation between the actual temperature and a preset target temperature using the working PID gain; Step S4: synthesizing the basic driving instruction and the feedback correction instruction to generate a composite driving instruction; Step S5: using the composite driving instruction to control the driving circuit to drive the LED light source module.

[0015] In summary, this application includes at least one of the following beneficial technical effects: 1. This application provides a feedforward control module that can directly calculate the basic drive command based on the target brightness command. Because this calculation process does not rely on feedback adjustment of the system state error, the system's response to user commands can be freed from the dynamic process limitations of the feedback loop, thereby achieving a rapid response to brightness adjustment commands. 2. This application sets up a feedback control module to obtain the actual temperature of the light source in real time and compare it with the preset target temperature. Based on this, it calculates the feedback correction instruction and combines it with the basic drive instruction. This structure can continuously compensate for system disturbances caused by factors such as thermal effects in a closed loop, ensuring that the LED light source can stably operate at the set operating temperature point and maintain the stability of its output brightness and color temperature. 3. By implementing a gain scheduling module, this application can predict the thermal disturbances that will be caused by changes in the brightness command, and proactively adjust the control parameters of the feedback control module accordingly. This adaptive parameter scheduling enables the control system to better adapt to upcoming state changes, effectively suppresses temperature overshoot and oscillation during the adjustment process, and improves the smoothness of the system's dynamic adjustment process. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is the system architecture diagram of this application; Figure 2 is a flow chart of the method of this application; DETAILED DESCRIPTION

[0017] Combined with attachment Figure 1 , further details of this application are given.

[0018] Embodiment: A medical cold light source control system, comprising: LED light source module; A temperature sensor thermally coupled to the LED light source module, used to obtain the actual temperature of the LED light source module; A driving circuit electrically connected to the LED light source module; The system physically comprises an LED light source module, a temperature sensor tightly thermally coupled to the module, a driver circuit for supplying power to the module, and a control unit serving as the core control system. Preferably, the control unit utilizes a digital signal processor (DSP) to meet the real-time computational requirements of complex control algorithms.

[0019] The control unit integrates multiple collaborative logic modules: a feedforward control module, a gain scheduling module, a feedback control module, and a command synthesis module. Together, these modules form a feedforward-feedback composite control architecture. The detailed workflow and implementation are as follows.

[0020] When the system receives a target brightness instruction from the user, the control process is triggered. The target brightness instruction represents the brightness level that the user expects the light source to achieve.

[0021] First, the front control module is activated. This module is designed to achieve a fast open-loop response to user commands. Specifically, the front control module pre-stores a nonlinear mapping model. This model is established through a large number of offline experimental calibrations and accurately describes the correspondence between different target brightness commands and the basic driving commands required to drive the LED light source module. Based on the received target brightness command, the front control module queries the nonlinear mapping model and instantly calculates a basic driving command C ff This process does not involve any closed-loop feedback, so its response speed is only limited by the computing power of the control unit, laying the foundation for rapid adjustment of the entire system.

[0022] The gain scheduling module operates in parallel. This module enables the system to proactively respond to changes in system state caused by brightness adjustments, particularly thermal disturbances. When brightness changes stepwise, the color temperature of the LED light source module fluctuates. If the feedback controller parameters are fixed, this can lead to overshoot or oscillation during the adjustment process.

[0023] To solve this problem, the gain scheduling module first calculates a predicted thermal disturbance ΔT based on the change between the current brightness and the target brightness through a built-in thermal characteristic function. pred The predicted thermal disturbance characterizes the trend and magnitude of temperature changes caused by this brightness adjustment.

[0024] Then, the gain scheduling module adjusts the thermal disturbance ΔT according to the predicted thermal disturbance ΔT. pred , through a preset scheduling function fgain For a set of inherent basic PID gains (K p ,K i ,K d ) is dynamically adjusted to generate a set of working PID gains (K ′ p ,K i ′ ,K ′ d ). Its generation relationship can be expressed as: (K ′ p ,K i ′ ,K ′ d )=f gain (ΔT pred ,K p ,K i ,K d ); This set of dynamically adjusted working PID gains will be provided to the subsequent feedback control module, so that the feedback control has the adaptive ability to deal with specific disturbances.

[0025] Next, the feedback control module performs its core function, which is to maintain the long-term stability of the system. The temperature sensor continuously measures the actual temperature Tact(t) of the LED light source module at a high frequency and transmits it to the feedback control module.

[0026] The feedback control module compares the actual temperature Tact(t) with a target temperature Tset preset to ensure the best performance of the light source, and calculates the temperature error e between the two. T (t).

[0027] Subsequently, the feedback control module executes the PID control algorithm and uses the dynamically adjusted working PID gain (K ′ p ,K i ′ ,K ′ d ), calculate the temperature error to generate a feedback correction instruction u fb (t). The purpose of this instruction is to compensate for all unforeseen system disturbances and accurately stabilize the actual temperature at the target temperature. Its control law can be described by the following formula: Among them, u fb (t) is the feedback correction instruction, e T (t) is the temperature error.

[0028] Finally, the instruction synthesis module integrates the instructions obtained in the above steps. It combines the basic driving instruction C that determines the response speed calculated by the feedforward control module ff , and the feedback correction instruction u calculated by the feedback control module to ensure system stability fb (t) is linearly superimposed to generate the final composite drive instruction u final (t). Its synthesis method is as follows: final (t) = C ff +u fb (t); Among them, u final (t) is the compound drive instruction.

[0029] The composite drive instruction is then sent to the driver circuit. Preferably, the driver circuit can be a pulse width modulation (PWM) driver circuit. After receiving the composite drive instruction, the driver circuit converts it into a PWM signal with a corresponding duty cycle to accurately control the current flowing through the LED light source module, thereby achieving precise control of the light source brightness.

[0030] Through the above approach, the control system disclosed in this embodiment organically combines open-loop feedforward control with closed-loop feedback control. The feedforward component ensures rapid system response to user commands, while the feedback component, optimized through gain scheduling, ensures high system stability during dynamic regulation and subsequent steady-state operation, thereby fully achieving the control objective.

[0031] A feedforward control module is used to calculate a basic driving instruction based on the received target brightness instruction; The feedforward control module begins by receiving a target brightness command from the user or a higher-level system. This command specifies the desired output level for the light source and serves as the trigger for the entire composite control process.

[0032] To enable rapid parsing and conversion of instructions, the feedforward control module incorporates a key technical component: a nonlinear mapping model, denoted as M. This nonlinear mapping model is not a theoretical derivation but rather was established through detailed offline calibration experiments on the LED light source module during the system design phase.

[0033] Specifically, during the calibration process, a series of drive commands of varying amplitudes are applied to the LED light source module, and the corresponding stable luminance output is measured using high-precision optical instruments. This yields a set of data points that accurately characterize the inherent "drive-to-light output" characteristics of that particular light source. The nonlinear mapping model M is a mathematical fit or table lookup of this data set. Preferably, this model is implemented using a lookup table to balance computational efficiency and accuracy.

[0034] When the current feed control module receives a specific target brightness instruction L cmd After that, its core operation is to query this nonlinear mapping model M to directly calculate the theoretical basis driving instruction C required to enable the light source to reach the target brightness. ff The process can be expressed as: C ff =M(L cmd ); Here, L cmd is the target brightness instruction, M is the nonlinear mapping model, C ff It is the basic driving instruction obtained by calculation.

[0035] The basic drive command C calculated here ff It is an open-loop, coarse-adjustment command value. Its "open-loop" feature means that its generation does not rely on any feedback information about the current actual state of the system (such as actual temperature or actual brightness), thus avoiding the time delay caused by the feedback loop.

[0036] The feedforward control module calculates the basic drive instruction C ff Afterwards, it is transmitted to the command synthesis module as the main component of the final composite drive command. On the other hand, the target brightness command received by this module also constitutes the initial input information for the gain scheduling module to calculate the predicted thermal disturbance, thereby triggering the subsequent dynamic adjustment process of the feedback control parameters.

[0037] In this way, the feedforward control module ensures the agile response of the entire control system to user intentions through its direct and fast open-loop calculation path, providing a basis for achieving high-performance dynamic regulation.

[0038] A feedback control module is used to calculate a feedback correction instruction based on the deviation between the actual temperature and a preset target temperature; The feedback control module forms a closed-loop control system with temperature as the controlled variable. It operates in parallel with the feedforward control module, but with different functional emphases: the former is responsible for the system's dynamic stability and steady-state accuracy, while the latter is responsible for the system's rapid response.

[0039] Specifically, the operation of the feedback control module is based on multiple key input information.

[0040] First, the real-time actual temperature Tact(t) from the temperature sensor. The temperature sensor is tightly thermally coupled to the LED light source module, enabling continuous measurement and providing temperature data reflecting the core junction temperature of the light source at a sufficiently high sampling frequency. This serves as the direct measurement basis for feedback control.

[0041] Second, there's a preset target temperature, Tset, which is loaded during system initialization. This value isn't set arbitrarily; it's an optimal operating temperature determined based on the LED light source module's characteristic curves for luminous efficacy, color temperature, and lifespan. The feedback control module's sole task is to drive the actual temperature toward this target temperature by adjusting its output.

[0042] The third, and also the key to the collaborative control characteristics of the present invention, is a set of dynamic working PID gains (K ′ p ,K i ′ ,K ′ d Unlike conventional feedback controllers that use fixed gains, the control parameters used by the feedback control module in this embodiment are proactively adjusted. In other words, each time a brightness adjustment occurs, the gain scheduling module pre-calculates the control parameters that are most suitable for addressing the thermal disturbances caused by that adjustment and provides them to the feedback control module.

[0043] After obtaining the above input, the feedback control module first performs error calculation. It compares the real-time actual temperature Tact(t) with the preset target temperature Tset and calculates the temperature error e at the current moment. T (t).

[0044] The feedback control module then executes its core PID (Proportional-Integral-Derivative) control algorithm. It uses the dynamic working PID gain (K ′ p ,K i ′ ,K ′ d ) for temperature error e T (t) is calculated to generate a feedback correction instruction u for fine adjustment fb (t). The complete mathematical expression of the control law is: In this formula: the proportional term K ′ p e T (t) provides an immediate correction force proportional to the current error size, which is the main part of eliminating the error; the integral term The historical errors are accumulated to eliminate the steady-state error of the system and ensure that the actual temperature is equal to the target temperature without deviation after the system stabilizes; the differential term Predictive adjustment is performed based on the changing trend of the error, which aims to suppress the oscillation and overshoot of the system and improve the smoothness of the dynamic process.

[0045] Feedback correction instruction u fb (t) is the output of the feedback control module and is sent to the command synthesis module. It represents the dynamic fine-tuning amount required to offset the temperature deviation at the current moment.

[0046] In this way, the feedback control module works continuously during the entire system operation. Whether in the transient process of brightness adjustment or under constant working conditions with stable brightness, it acts like a "stabilizer", constantly and accurately compensating for various thermal disturbances, thereby ensuring the consistency and reliability of the output characteristics of the LED light source module.

[0047] The gain scheduling module predicts the predicted thermal disturbance of the light source based on changes in the target brightness command. Based on this predicted thermal disturbance, it adjusts a set of basic PID gains to generate operating PID gains for use by the feedback control module. This gain scheduling module is activated synchronously with the feedforward control module, both triggered by changes in the target brightness command received by the system. The core issue it addresses is that different brightness adjustment tasks (for example, a step from low to high brightness versus a step from high to low brightness) have different thermal impacts on the system. Therefore, using fixed control parameters in a feedback control system makes it difficult to achieve optimal adjustment results under all operating conditions.

[0048] To achieve its functionality, the gain scheduling module performs two core steps: First, the calculation of predicted thermal disturbance is performed. When the target brightness instruction changes, the module will obtain the brightness value before and after the change, that is, the current brightness and the target brightness. Based on these two input values, it calls a thermal characteristic function pre-stored in the control unit. This function is a mathematical model that describes the relationship between the power change of the light source and its junction temperature response. Preferably, the model is established after sufficient experimental testing and thermal characteristic analysis of the LED light source module. Through this function, the module can calculate a quantitative predicted thermal disturbance value ΔT pred This value represents the magnitude and direction of the instantaneous impact that this brightness adjustment will have on the LED junction temperature.

[0049] Secondly, the dynamic scheduling of PID gains is performed. pred After that, the core function of the gain scheduling module is to execute the gain scheduling. A set of basic PID gains (K p ,K i ,K d ), this set of gains is suitable for the system working in steady state or under small disturbance.

[0050] The gain scheduling module uses a specific scheduling function f gainAdjust this set of basic PID gains. The scheduling function is to predict the thermal disturbance ΔT pred and basic PID gain (K p ,K i ,K d ) as input, and output a set of temporary working PID gains (K ′ p ,K i ′ ,K ′ d ). The scheduling relationship can be expressed as follows: (K ′ p ,K i ′ ,K ′ d )=f gain (ΔT pred ,K p ,K i ,K d ); Among them, (K ′ p ,K i ′ ,K ′ d ) is the working PID gain, f gain is the scheduling function, ΔT pred To predict thermal disturbances, (K p ,K i ,K d ) is the basic PID gain.

[0051] For example, if a large temperature rise (ΔT pred is a large positive value), the scheduling function f gain The differential gain K may be increased moderately ′ d , in order to enhance the system's ability to suppress temperature change trends, thereby preventing temperature overshoot; conversely, if it is predicted that the temperature will drop, another set of parameter combinations may be used to ensure the rapidity of adjustment.

[0052] Finally, the generated, targeted working PID gain (K ′ p ,K i ′ ,K ′ d ) is the output of the gain scheduling module and is immediately transmitted to the feedback control module.

[0053] The instruction synthesis module is used to synthesize the basic driving instruction and the feedback correction instruction to generate a composite driving instruction, and use the composite driving instruction to control the driving circuit.

[0054] The instruction synthesis module is located at the end of the entire control process and serves as a bridge between the control algorithm and the physical drive. It receives two parallel input signals, which represent the products of two different control philosophies of the control system.

[0055] First, the basic drive instruction C from the feedforward control module ff This instruction is based on the target brightness instruction issued by the user and is directly calculated through an open-loop nonlinear mapping model. It provides a target set point for the system and is the basis for achieving fast response.

[0056] The second is the feedback correction instruction u from the feedback control module fb (t). This instruction is generated based on real-time closed-loop monitoring of the actual temperature of the light source and represents the dynamic and fine adjustment required to offset various disturbances in the system (such as thermal effects, ambient temperature changes, etc.).

[0057] The core function of the instruction synthesis module is to linearly superimpose these two different instructions to form a unified composite drive instruction u final (t). The synthesis process follows the following formula: u final (t) = C ff +u fb (t); In this formula: u final (t) is the composite drive instruction, which is the final output of the module; C ff It is the basic driving instruction, constitutes the main part of the compound instruction, and determines the approximate amplitude of the drive; fb (t) is the feedback correction instruction, which constitutes the dynamic fine-tuning part of the composite instruction and is responsible for making real-time corrections based on the main part.

[0058] By synthesizing, the two instruction components complement each other. ff This ensures that when the user sets a new brightness, the system can immediately adjust the drive command to a level close to the final stable state, thereby bypassing the slow ramp-up process of the feedback system. fb (t) then continues to work on this basis, accurately compensating for all deviations and disturbances that the feedforward path fails to take into account, and ultimately stabilizing the system state (i.e., temperature) precisely at the preset target point.

[0059] Finally, the instruction synthesis module calculates the composite drive instruction ufinal (t) is its only output and is transmitted to the driving circuit.

[0060] A driving circuit, such as a pulse width modulation (PWM) driver, faithfully converts this numerical composite driving instruction into a specific physical electrical signal (such as a PWM wave with a specific duty cycle) to control the energy flowing through the LED light source module, thereby achieving precise regulation of the light source output.

[0061] Combined with attachment Figure 2 Another embodiment of the present application provides a method for controlling a medical cold light source, comprising the following steps: S1. Receive a target brightness instruction and calculate a basic driving instruction based on the target brightness instruction; S2. predicting the predicted thermal disturbance of the light source according to the change of the target brightness instruction; S3. adjusting a set of basic PID gains based on the predicted thermal disturbance to generate working PID gains; S4, obtaining the actual temperature of the LED light source module in real time; S5. Calculating a feedback correction instruction based on a deviation between the actual temperature and a preset target temperature and using a working PID gain; S6. Combining the basic driving instruction with the feedback correction instruction to generate a composite driving instruction; S7. Use the composite drive instruction to control the drive circuit to drive the LED light source module.

[0062] The method of this embodiment can be used to execute the above system embodiment. Its principles and technical effects are similar and will not be described in detail here.

[0063] The examples of this specific embodiment are all preferred embodiments of this application and are not intended to limit the scope of protection of this application. Identical components are represented by the same reference numerals. Therefore, any equivalent changes made based on the structure, shape, and principle of this application should be included in the scope of protection of this application.

Claims

1. Medical cold light source control system, characterized in that, include: LED light source module; A temperature sensor thermally coupled to the LED light source module, used to obtain the actual temperature of the LED light source module; a driving circuit, electrically connected to the LED light source module; A feedforward control module is used to calculate a basic driving instruction based on the received target brightness instruction; A feedback control module, configured to calculate a feedback correction instruction based on a deviation between the actual temperature and a preset target temperature; a gain scheduling module, configured to predict a predicted thermal disturbance of the light source according to a change in the target brightness command, and adjust a set of basic PID gains based on the predicted thermal disturbance to generate an operating PID gain for use by the feedback control module; An instruction synthesis module is used to synthesize the basic driving instruction and the feedback correction instruction to generate a composite driving instruction, and use the composite driving instruction to control the driving circuit.

2. The medical cold light source control system according to claim 1, characterized in that: The feedforward control module has a built-in nonlinear mapping model describing the relationship between the target brightness instruction and the basic driving instruction, and is configured to calculate the basic driving instruction by querying the nonlinear mapping model.

3. The medical cold light source control system according to claim 2, characterized in that: The nonlinear mapping model is a lookup table established through offline calibration.

4. The medical cold light source control system according to claim 1, characterized in that: The feedback control module is configured to execute a PID control algorithm and calculate the feedback correction instruction using the working PID gain using the following formula: Among them, u fb (t) is the feedback correction instruction, e T (t) is the deviation between the preset target temperature and the actual temperature, K ′ p ,K i ′ ,K ′ d is the working PID gain.

5. The medical cold light source control system according to claim 1, characterized in that: The instruction synthesis module generates a composite drive instruction using the following formula: u final (t)=C ff +u fb (t); Among them, u final (t) is the compound drive instruction, C ff Is the basic driving instruction, u fb (t) is the feedback correction instruction.

6. The medical cold light source control system according to claim 1, characterized in that: The gain scheduling module generates the working PID gain through the scheduling function: (K ′ p ,K i ′ ,K ′ d )=f gain (ΔT pred ,K p ,K i ,K d ); Among them, (K ′ p ,K i ′ ,K ′ d ) is the working PID gain, f gain is the scheduling function, ΔT pred To predict thermal disturbances, (K p ,K i ,K d ) is the basic PID gain.

7. The medical cold light source control system according to claim 1, characterized in that: The gain scheduling module calculates the predicted thermal disturbance using a thermal characteristic function, where the thermal characteristic function characterizes the relationship between light source brightness change and temperature change.

8. The medical cold light source control system according to claim 1, characterized in that: The feedforward control module, feedback control module, gain scheduling module and instruction synthesis module are implemented by a digital signal processor.

9. The medical cold light source control system according to claim 1, characterized in that: The driving circuit generates a pulse width modulation signal according to the composite driving instruction to drive the LED light source module.

10. A medical cold light source control method, according to the medical cold light source control system according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1. Receive a target brightness instruction, and calculate a basic driving instruction based on the target brightness instruction; S2. predicting a predicted thermal disturbance of the light source according to a change in the target brightness instruction; S3. Adjusting a set of basic PID gains based on the predicted thermal disturbance to generate working PID gains; S4, obtaining the actual temperature of the LED light source module in real time; S5. Calculating a feedback correction instruction based on a deviation between the actual temperature and a preset target temperature and using the working PID gain; S6. Combining the basic driving instruction with the feedback correction instruction to generate a composite driving instruction; S7. Use the composite driving instruction to control the driving circuit to drive the LED light source module.

Images