Adaptive Loop Compensation Method for High-Current Switching Power Supply Based on Digital Control

Abstract

The present invention relates to the technical field of power supply control, and discloses an adaptive loop compensation method for a high-current switching power supply based on digital control, which is applied to a DSP chip and includes: sampling the output voltage of the target high-current switching power supply at a pre-determined sampling frequency to obtain a sampled voltage signal; respectively calculating the differences between the sampled voltage signal and multiple reference signals to obtain multiple duty cycle signals; generating multiple PWM signals based on the multiple duty cycle signals, and the multiple PWM signals act alternately to control the on and off of the switching tube, wherein the multiple reference signals are alternated in the following manner: when it is detected that the loop load changes, the updated load is collected and the loop load change rate and the loop load change amount are calculated; if the loop load change amount is greater than a preset change amount threshold, a target reference signal is selected from the multiple reference signals according to the updated load, and the target reference signal is applied to the switching tube. Thereby, the performance of the high-current switching power supply is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of power control, and particularly to an adaptive loop compensation method for a high-current switching power supply based on digital control. Background Art

[0002] High-current switching power supplies are indispensable for the normal operation of electronic devices. With the development of modern technology, the performance requirements for high-current switching power supplies are getting higher and higher, especially in terms of loop compensation. Therefore, researching effective adaptive loop compensation methods is of great significance for ensuring the stability and reliability of high-current switching power supplies.

[0003] In existing high-current switching power supplies with digital control, the following technical problems often exist:

[0004] First, existing high-current switching power supplies are difficult to cope with dynamic load changes and input condition changes, and lack an adaptive mechanism that can adjust compensation parameters in real time according to load changes, resulting in unstable power supply performance under different loads;

[0005] Second, existing loop compensation methods cannot flexibly adjust compensation parameters according to load changes and the actual requirements of the output voltage, resulting in the inability to maintain loop stability in real time, and the selection and adjustment of compensation parameters do not consider the dynamic response before and after load changes, resulting in unreliable power supply output;

[0006] Third, existing methods lack accurate extraction of input and output voltage characteristics, and use fixed compensation parameters without considering whether the voltage change meets the stability requirements, making it difficult to dynamically adjust according to real-time voltage changes and load fluctuations, resulting in poor adaptive ability of the power supply. Summary of the Invention

[0007] This part of the present invention is used to briefly introduce concepts, which will be described in detail in the following detailed implementation part. This part of the present invention is not intended to identify the key features or essential features of the claimed technical solution, nor is it intended to limit the scope of the claimed technical solution.

[0008] The present invention proposes an adaptive loop compensation method for a high-current switching power supply based on digital control to solve one or more of the technical problems mentioned in the above background art part.

[0009] The present invention provides an adaptive loop compensation method for a high-current switching power supply based on digital control, which is applied to a DSP chip and includes:

[0010] Sampling the output voltage of the target high-current switching power supply at a pre-determined sampling frequency to obtain a sampled voltage signal;

[0011] Calculate the difference between the sampled voltage signal and multiple reference signals respectively to obtain multiple duty cycle signals;

[0012] Based on the multiple duty cycle signals, generate multiple PWM signals, and the multiple PWM signals act alternately to control the on and off of the switching tube. Among them, the multiple reference signals are alternated in the following way: when it is detected that the loop load changes, collect and update the load, and calculate the loop load change rate and the loop load change amount; if the loop load change amount is greater than the preset change amount threshold, select the target reference signal from the multiple reference signals according to the updated load, and make the target reference signal act on the switching tube.

[0013] Optionally, the adaptive loop compensation method for a high-current switching power supply based on digital control of the present invention further includes:

[0014] Collect the first compensation parameter before load update and the second compensation parameter after load update. If the loop load change rate is greater than the preset load change rate, determine the actual parameter change rate according to the first compensation parameter and the second compensation parameter;

[0015] If the actual parameter change rate is greater than the preset change rate threshold, then construct a compensation parameter interval according to the first compensation parameter and the second compensation parameter, and extract a target number of compensation parameters from the compensation parameter interval as a candidate compensation parameter sequence;

[0016] Perform adaptive loop compensation based on the candidate compensation parameter sequence.

[0017] Optionally, the target number is determined according to the difference between the first compensation parameter and the second compensation parameter.

[0018] Optionally, performing adaptive loop compensation based on the candidate compensation parameter sequence includes:

[0019] Use the i-th compensation parameter in the candidate compensation parameter sequence for loop compensation, and collect the output voltage after the action of the (i - 1)-th compensation parameter and the output voltage after the action of the i-th compensation parameter; calculate the voltage change value between the output voltage after the action of the (i - 1)-th compensation parameter and the output voltage after the action of the i-th compensation parameter;

[0020] Determine whether the voltage change value meets the voltage stability verification condition. If the voltage change value meets the voltage stability verification condition, continue to use the (i + 1)-th compensation parameter for loop compensation; if the voltage change value does not meet the voltage stability verification condition, stop using the (i + 1)-th compensation parameter for loop compensation.

[0021] The present invention has the following beneficial effects:

[0022] 1. The stability of the power supply performance is improved. Specifically, by sampling the output voltage signal of the target high-current switching power supply and calculating the difference with multiple reference signals to generate multiple duty cycle signals, and then generating alternating multiple PWM signals based on the multiple duty cycle signals to control the on and off of the switching transistor. At the same time, by detecting the change of the loop load and selecting a suitable reference signal for compensation according to the load change amount to achieve adaptive loop compensation, ensuring the stable output of the power supply, thereby improving the stability of the power supply performance.

[0023] 2. The output stability and reliability of the high-current switching power supply are optimized. Specifically, by collecting the compensation parameters before and after the load update, calculating the actual parameter change rate, and constructing a compensation parameter interval according to the change rate. Then, select the target number of compensation parameters and perform adaptive loop compensation based on these candidate compensation parameter sequences. By real-time monitoring the voltage change, ensure that the adjustment of the compensation parameters can meet the voltage stability verification conditions. Introducing a compensation parameter sequence dynamically adjusted based on the load change and the stability verification of the voltage change can flexibly adjust the compensation parameters according to the load change and voltage fluctuation, thereby optimizing the output stability and reliability of the high-current switching power supply.

[0024] 3. The stability and adaptive ability of the high-current switching power supply under complex load and voltage change conditions are improved. Specifically, first, the input voltage and output voltage are tracked and monitored, and the voltage characteristics are extracted. According to the voltage fluctuation situation, the historical time period with smaller voltage fluctuation is used as the reference historical time period, and the compensation parameters are extracted and averaged from it. Then, the input voltage characteristics are associated with the average compensation parameters and stored as a compensation parameter binary group. Finally, when the voltage change does not meet the stable verification conditions, select the target compensation parameters from the compensation parameter binary group and perform adaptive loop compensation based on this. By introducing the screening of the reference historical time period based on voltage fluctuation and the dynamic association of compensation parameters, the stability and adaptive ability of the high-current switching power supply under complex load and voltage change conditions are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In combination with the accompanying drawings and referring to the following specific embodiments, the above and other features, advantages and aspects of the embodiments of the present invention will become more obvious. Throughout the drawings, the same or similar reference numerals represent the same or similar elements. It should be understood that the drawings are schematic, and the elements and elements are not necessarily drawn to scale.

[0026] Figure 1 is a flowchart of the adaptive loop compensation method for a high-current switching power supply based on digital control of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0027] The present invention will be described in more detail below with reference to the accompanying drawings. Although some embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. On the contrary, these embodiments are provided to more thoroughly and completely understand the present invention. It should be understood that the drawings and embodiments of the present invention are only for exemplary purposes and are not used to limit the protection scope of the present invention.

[0028] In addition, it should be noted that for ease of description, only parts related to the relevant invention are shown in the drawings. Without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0029] It should be noted that the concepts such as "first" and "second" mentioned in the present invention are only used to distinguish different devices, modules or units, and are not used to limit the order or interdependence of the functions performed by these devices, modules or units.

[0030] It should be noted that the modifications of "one" and "multiple" mentioned in the present invention are illustrative rather than restrictive. Those skilled in the art should understand that unless otherwise clearly specified in the context, it should be understood as "one or more".

[0031] The names of the messages or information exchanged between multiple devices of the present invention are only for illustrative purposes and are not used to limit the scope of these messages or information.

[0032] The present invention will be described in detail below with reference to the drawings and in combination with embodiments.

[0033] As Figure 1 shown, a flowchart of the adaptive loop compensation method for a high-current switched-mode power supply based on digital control of the present invention is shown. The adaptive loop compensation method for a high-current switched-mode power supply based on digital control is applied to a DSP chip and specifically includes the following steps:

[0034] Step 101, sample the output voltage of the target high-current switched-mode power supply at a pre-determined sampling frequency to obtain a sampled voltage signal.

[0035] In some embodiments, the execution subject of the adaptive loop compensation method for a high-current switched-mode power supply based on digital control of the present invention is a DSP chip. Among them, a DSP (Digital Signal Processing) chip refers to a chip that can implement digital signal processing technology. Digital signal processing technology refers to the technology of converting analog information (such as sound, video, and pictures) into digital information.

[0036] In practice, the pre-determined sampling frequency refers to the pre-set number of times of sampling the analog signal per second. As an example, if the sampling frequency is set to 100 kHz, the DSP performs 100,000 samplings per second. On this basis, the output voltage of the target high-current switching power supply is sampled in real time at the pre-determined sampling frequency through the ADC (Analog to Digital Converter) of the DSP chip and converted into a digitalized sampled voltage signal. Among them, the high-current switching power supply is a switching-mode power supply that can provide a high-current output and is used for loads that require high power, such as servers, motor drives, communication base stations, etc. The sampled voltage signal refers to the data obtained after converting the output voltage of the switching power supply into a digital signal. The ADC is usually used to convert an analog signal into a digital signal.

[0037] Step 102: Calculate the difference between the sampled voltage signal and multiple reference signals respectively to obtain multiple duty cycle signals.

[0038] In some embodiments, the reference signal is a pre-set digitalized voltage signal used as the target reference value, and each reference signal corresponds to a different load or working state. On this basis, the difference between the sampled voltage signal and each reference signal is calculated respectively using the PID algorithm to obtain the error signals of each path. Then, the error signals of each path are used through the PID algorithm to generate the duty cycle signals of each path, obtaining multiple duty cycle signals. Among them, the PID (Proportional-Integral-Derivative) algorithm is a linear control algorithm that adjusts the system error through three control methods: proportional, integral, and derivative to achieve precise control. The duty cycle signal is generated by comparing the error difference between the reference signal and the actual sampled voltage.

[0039] Step 103: Generate multiple PWM signals based on the multiple duty cycle signals, and the multiple PWM signals act alternately to control the on and off of the switching tubes. Among them, the multiple reference signals are alternated in the following way: when it is detected that the loop load changes, the updated load is collected and the loop load change rate and loop load change amount are calculated; if the loop load change amount is greater than the preset change amount threshold, the target reference signal is selected from the multiple reference signals according to the updated load, and the target reference signal acts on the switching tube.

[0040] In some embodiments, according to the multi-channel duty cycle signals, through the PWM generation program and the preset period signals, multi-channel PWM signals required for control are generated, and each PWM signal controls different switching elements. Among them, PWM is a modulation method that controls power delivery by adjusting the duration of the high level (on) of the signal. The frequency of the PWM signal is usually fixed, and the duty cycle determines the energy transmission within each cycle. In a switching power supply, the PWM signal controls the conduction and cut-off of the switching transistor, thereby adjusting the output of the power supply. The multi-channel PWM signals can act alternately to control power conversion elements of different phases.

[0041] In practice, the multi-channel reference signals are alternated in the following way: The loop load change is monitored in real time through a load detection mechanism. The loop load change rate and the loop load change amount are calculated. Among them, the loop load change rate is used to describe the speed or rate of load change and is usually used to reflect the dynamic change of the load. For example, the rate of current change can be used as the load change rate. The loop load change amount is used to describe the change amplitude of the load within a certain time period. For example, if the load increases from 5A to 10A, the load change amount is 5A. The preset change amount threshold refers to the preset change amount threshold used to determine whether the load change is significant enough to require switching the reference signal. On this basis, if the loop load change amount is greater than the preset change amount threshold, a new reference signal is selected from the multi-channel reference signals according to the updated load as the target reference signal. According to the target reference signal, the duty cycle signal is updated, and corresponding PWM signals are regenerated to control the conduction and cut-off of the switching transistor. As an example, assume a 12V power supply system needs to adjust the output voltage according to the load change. When the load current increases from 5A to 10A, the load change is detected by a current sensor, and the load change amount is calculated to be 5A. If the preset load change amount threshold is 3A, then according to the load change, a new reference signal (such as a 12.5V reference signal) is selected, and the duty cycle signal is adjusted accordingly, and the PWM signal is updated to control the conduction state of the switching transistor.

[0042] In these embodiments, the stability of the power supply performance is improved. Specifically, by sampling the output voltage signal of the target high-current switching power supply and performing difference calculation with the multi-channel reference signals to generate multi-channel duty cycle signals, and then generating alternating multi-channel PWM signals based on the multi-channel duty cycle signals to control the on and off of the switching transistor. At the same time, by detecting the loop load change and selecting a suitable reference signal for compensation according to the load change amount to achieve adaptive loop compensation, ensuring the stability of the power supply output, thereby improving the stability of the power supply performance.

[0043] In some embodiments, in order to further solve Technical Problem 2 described in the background art, that is, "the existing loop compensation method cannot flexibly adjust compensation parameters according to load changes and the actual requirements of the output voltage, resulting in the inability to maintain loop stability in real time, and the selection and adjustment of compensation parameters do not consider the dynamic response before and after load changes, resulting in unreliable power output", some embodiments of the present invention further include:

[0044] Step 1: Collect the first compensation parameter before load update and the second compensation parameter after load update. If the loop load change rate is greater than the preset load change rate, determine the actual parameter change rate according to the first compensation parameter and the second compensation parameter.

[0045] In some embodiments, the compensation parameter refers to the parameter used to adjust the switching power supply loop (such as the feedback control loop), and is usually used to adjust the stability of voltage, current or power. The first compensation parameter refers to the control parameter before load change. For example, it is the control setting when the load is at the initial value. The second compensation parameter refers to the control parameter after load update. For example, it is the control setting when the load changes. The DSP chip is used to monitor the load change in real time and collect the feedback signals (such as output voltage and current) of the power supply to determine the compensation parameter. The preset load change rate is a constant preset during design, indicating the reference rate of load change. The loop load change rate refers to the loop load change amount within a preset time period. For example, a reference time (such as 1 second) is set, and the change amount of the load current within this time is calculated to obtain the load change rate. On this basis, if the loop load change rate is greater than the preset load change rate, the actual parameter change rate is determined according to the first compensation parameter and the second compensation parameter. Among them, the actual parameter change rate is the change speed of the compensation parameter calculated according to the load change rate, indicating the response speed of the parameters in the control loop to the load change. As an example, the time period between before and after load update is used as the load change time, the second compensation parameter is subtracted from the first compensation parameter, and then divided by the load change time to obtain the actual parameter change rate.

[0046] Step 2: If the actual parameter change rate is greater than the preset change rate threshold, construct a compensation parameter interval according to the first compensation parameter and the second compensation parameter, and extract a target number of compensation parameters from the compensation parameter interval as the candidate compensation parameter sequence.

[0047] In some embodiments, the preset change rate threshold is a design parameter used to compare with the actual parameter change rate. Based on this, if the actual parameter change rate is greater than the preset change rate threshold, the change range is determined by calculating the difference between the first compensation parameter and the second compensation parameter, and a compensation parameter interval is constructed. The compensation parameter interval refers to the parameter adjustment range determined by the change range between the first compensation parameter and the second compensation parameter. This interval contains the compensation parameter values that may be used for adjustment control. After constructing the compensation parameter interval, a target number of candidate compensation parameters are extracted from the interval according to certain rules (such as equal-interval sampling), and the target number of candidate compensation parameters are integrated into a candidate compensation parameter sequence. The candidate compensation parameter sequence is a set of multiple candidate compensation parameters extracted from the compensation parameter interval, and these parameters are used for further adaptive compensation. As an example, the compensation parameter interval constructed according to the first compensation parameter and the second compensation parameter is [2.0, 2.5], and a target number (2) of candidate compensation parameters such as 2.1 and 2.3 are extracted from it.

[0048] Step 3: Perform adaptive loop compensation based on the candidate compensation parameter sequence.

[0049] In some embodiments, the most suitable compensation parameter is selected from the candidate compensation parameter sequence according to the voltage change value for adaptive loop compensation.

[0050] The target number is determined according to the difference between the first compensation parameter and the second compensation parameter.

[0051] In some embodiments, the determination of the target number is based on the difference between the first compensation parameter and the second compensation parameter. Through a set mapping relationship, it is decided how many compensation parameters to extract to optimize the adaptive compensation process of the system. This can ensure the smoothness of the compensation adjustment and prevent the system from being unstable or having an overshoot in transient response. In practice, if the change in the compensation parameter is small, it indicates that the load change has a small impact on the system, and only a small number of compensation parameters are required for adjustment. If the change in the compensation parameter is large, it indicates that the load change is large, and more compensation parameters are required for smooth transition to prevent the system from oscillating or having an overshoot in transient response.

[0052] Among them, performing adaptive loop compensation based on the candidate compensation parameter sequence includes:

[0053] Step 1: Use the i-th compensation parameter in the candidate compensation parameter sequence for loop compensation, and collect the output voltage after the action of the (i - 1)-th compensation parameter and the output voltage after the action of the i-th compensation parameter; calculate the voltage change value between the output voltage after the action of the (i - 1)-th compensation parameter and the output voltage after the action of the i-th compensation parameter.

[0054] In some embodiments, after selecting the \(i\)th compensation parameter from the candidate compensation parameter sequence for loop compensation, the output voltage after the action of the \((i - 1)\)th compensation parameter and the output voltage after the action of the \(i\)th compensation parameter are collected by the voltage sampling module. The difference between the output voltage after the action of the \((i - 1)\)th compensation parameter and the output voltage after the action of the \(i\)th compensation parameter is taken and the absolute value is obtained to get the voltage change value. Here, the voltage change value refers to the change amount of the output voltage under the action of different compensation parameters.

[0055] Step 2: Determine whether the voltage change value meets the voltage stability verification condition. If the voltage change value meets the voltage stability verification condition, continue to use the \((i + 1)\)th compensation parameter for loop compensation; if the voltage change value does not meet the voltage stability verification condition, stop using the \((i + 1)\)th compensation parameter for loop compensation.

[0056] In some embodiments, the voltage stability verification condition is a set condition used to determine whether the output voltage of the system remains stable. In a stable system, the output voltage should be stable and the change range should be controlled within a reasonable range. If the voltage change value meets the stability condition, continue to use the \((i + 1)\)th compensation parameter for loop compensation. If the voltage change value does not meet the voltage stability verification condition, stop using the \((i + 1)\)th compensation parameter for loop compensation. As an example, assume that we have a candidate compensation parameter sequence of \(a\), \(b\), \(c\), \(d\), and the change amplitude of the output voltage is set to be less than 0.05 V as the voltage stability verification condition. The output voltage generated after applying the first candidate compensation parameter \(a\) is \(V1\), and the output voltage generated after applying the second candidate compensation parameter \(b\) is \(V2\). After selecting the second candidate compensation parameter \(b\) for loop compensation, \(V2\) and \(V1\) are collected and the difference between \(V2\) and \(V1\) is calculated, and the absolute value of the difference is taken to get the voltage change value. If the voltage change value is less than or equal to 0.05 V, it indicates that the system output is stable, and then continue to use the third compensation parameter \(c\). If the voltage change value is greater than 0.05 V, stop using the subsequent compensation parameters \(c\) and \(d\).

[0057] In these embodiments, the output stability and reliability of the high - current switching power supply are optimized. Specifically, by collecting the compensation parameters before and after the load is updated, calculating the actual parameter change rate, and constructing a compensation parameter interval according to the change rate. Then, select the target number of compensation parameters and perform adaptive loop compensation based on these candidate compensation parameter sequences. By monitoring the voltage change in real time, ensure that the adjustment of the compensation parameters can meet the voltage stability verification condition. Introducing a compensation parameter sequence dynamically adjusted based on load changes and a stability verification of voltage changes can flexibly adjust the compensation parameters according to load changes and voltage fluctuations, thereby optimizing the output stability and reliability of the high - current switching power supply.

[0058] In some embodiments, in order to further solve Technical Problem 3 described in the background art section, that is, "the existing methods lack accurate input and output voltage feature extraction, use fixed compensation parameters and do not consider whether the voltage change meets the stability requirements, making it difficult to perform dynamic adjustment according to real-time voltage changes and load fluctuations, resulting in poor adaptability of the power supply", some embodiments of the present invention further include:

[0059] Step 1: Track and monitor the input voltage signal of the target high-current switching power supply, obtain the input voltage monitoring data corresponding to each historical time period in multiple historical time periods, and perform feature extraction on the input voltage monitoring data to obtain input voltage features.

[0060] In some embodiments, the voltage sampling circuit in the DSP chip is used to monitor the voltage at the input end of the target high-current switching power supply in real time. The input voltage signal is divided into multiple time periods at a certain time interval. The input voltage data within each time period will be recorded and analyzed. Through signal processing algorithms, the input voltage features corresponding to each historical time period are extracted. Among them, the input voltage signal is the voltage signal at the input end of the high-current switching power supply. The historical time period refers to multiple time periods divided by time, and there are different input and output voltage data within each time period. The input voltage feature is a representative feature extracted from the input voltage monitoring data, which may include the mean value, fluctuation range, change rate, etc. of the input voltage.

[0061] Step 2: Track and monitor the actual output voltage of the target high-current switching power supply, obtain the average output voltage, voltage fluctuation value within each time period, and the average voltage fluctuation value corresponding to each historical time period.

[0062] In some embodiments, the actual output voltage at the output terminal of the target high-current switching power supply is monitored in real time by using the voltage sampling circuit in the DSP chip. For continuous voltage signals, the integral formula can be used to calculate the average output voltage within each time period. The difference operation is performed between the maximum value and the minimum value of the actual output voltage within each time period to obtain the voltage fluctuation value within each time period. And the average voltage fluctuation value of all time periods is calculated. Among them, the voltage fluctuation value refers to the change amplitude of the voltage signal within a certain time period. The average voltage fluctuation value is the average value of the output voltage fluctuation values within multiple time periods. As an example, first, the average output voltage in time period 1 of the monitored output voltage is 11.8V, the fluctuation range is 0.2V, the average output voltage in time period 2 is 11.7V, the fluctuation range is 0.3V, the average output voltage in time period 3 is 12.0V, the fluctuation range is 0.1V, and the average output voltage in time period 4 is 11.9V, the fluctuation range is 0.1V. Then, the voltage fluctuation value of each time period is calculated, and the voltage fluctuation value in time period 1 is 0.2V, the voltage fluctuation value in time period 2 is 0.3V, the voltage fluctuation value in time period 3 is 0.1V, and the voltage fluctuation value in time period 4 is 0.1V. Finally, the average value of the voltage fluctuation values in 4 time periods is calculated.

[0063] Step 3: Determine the reference historical time periods with voltage fluctuation values less than the average voltage fluctuation value, extract multiple compensation parameters for each reference historical time period and find their average value to obtain the average compensation parameter for each reference historical time period.

[0064] In some embodiments, by comparing the voltage fluctuation value of each historical time period with the average voltage fluctuation value, the time periods with voltage fluctuation values less than the average fluctuation value are selected as the reference historical time periods. From the corresponding operation database within the reference historical time periods, the corresponding multiple compensation parameters are extracted. For each reference historical time period, the average value of the multiple compensation parameters is calculated to obtain the average compensation parameter for each reference historical time period.

[0065] Step 4: For each reference historical time period, associate the corresponding input voltage characteristics with the average compensation parameter to obtain multiple compensation parameter pairs and store them.

[0066] In some embodiments, the input voltage characteristics of each reference historical time period are associated with its corresponding average compensation parameter and combined into a compensation parameter pair, and these association information can be recorded through a database. Among them, the compensation parameter pair is a pair composed of the input voltage characteristics and the corresponding average compensation parameter.

[0067] Step 5: If the voltage change value does not meet the voltage stability verification condition, stop using the (i + 1)-th compensation parameter for loop compensation, select a target compensation parameter pair from multiple compensation parameter pairs, and use the average compensation parameter included in the target compensation parameter pair for loop compensation.

[0068] In some embodiments, if the voltage change value does not meet the voltage stability verification condition, stop using the (i + 1)-th compensation parameter for loop compensation, and find the most matching compensation parameter pair from multiple compensation parameter pairs according to the input voltage characteristics as the target compensation parameter pair. And perform loop compensation according to the selected target compensation parameter.

[0069] In these embodiments, the stability and adaptive ability of the high-current switching power supply under complex load and voltage change conditions are improved. Specifically, first, the input voltage and output voltage are tracked and monitored, and the voltage characteristics are extracted. According to the voltage fluctuation situation, the historical time period with smaller voltage fluctuation is used as the reference historical time period, and the compensation parameters are extracted and averaged from it. Then, the input voltage characteristics are associated with the average compensation parameter and stored as a compensation parameter pair. Finally, when the voltage change does not meet the stability verification condition, a target compensation parameter is selected from the compensation parameter pairs, and adaptive loop compensation is performed based on this. By introducing the screening of the reference historical time period based on voltage fluctuation and the dynamic association of compensation parameters, the stability and adaptive ability of the high-current switching power supply under complex load and voltage change conditions are improved.

[0070] The above description is only some preferred embodiments of the present invention and an explanation of the applied technical principles. Those skilled in the art should understand that the scope of the invention involved in the present invention is not limited to the technical solutions formed by the specific combination of the above technical features, and should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the above inventive concept. For example, the technical solutions formed by mutually replacing the above features with the (but not limited to) technical features with similar functions disclosed in the present invention.

Claims

1. A high current switching power supply adaptive loop compensation method based on digital control, applied to DSP chip, characterized in that: include: The output voltage of the target high-current switching power supply is sampled according to a predetermined sampling frequency to obtain a sampled voltage signal; The sampled voltage signal and the multiple reference signals are respectively subjected to difference calculation to obtain multiple duty cycle signals; Based on the multiple duty cycle signals, multiple PWM signals are generated, and the multiple PWM signals act alternately to control the on and off of the switch tube, wherein the multiple reference signals are alternated in the following manner: when a change in the loop load is detected, the load is collected and updated, and the loop load change rate and the loop load change amount are calculated; if the loop load change amount is greater than a preset change amount threshold, a target reference signal is selected from the multiple reference signals according to the updated load, and the target reference signal is applied to the switch tube; Collecting a first compensation parameter before the load is updated and a second compensation parameter after the load is updated, and if the loop load change rate is greater than a preset load change rate, determining an actual parameter change rate according to the first compensation parameter and the second compensation parameter; If the actual parameter change rate is greater than a preset change rate threshold, constructing a compensation parameter interval according to the first compensation parameter and the second compensation parameter, and extracting a target number of compensation parameters from the compensation parameter interval as a candidate compensation parameter sequence; Adaptive loop compensation is performed based on the candidate compensation parameter sequence.

2. The adaptive loop compensation method for a high current switching power supply based on digital control according to claim 1, characterized in that: The target quantity is determined according to a difference between the first compensation parameter and the second compensation parameter.

3. The adaptive loop compensation method for a high current switching power supply based on digital control according to claim 2, characterized in that: The performing adaptive loop compensation based on the candidate compensation parameter sequence comprises: Perform loop compensation using the i-th compensation parameter in the candidate compensation parameter sequence, and collect the output voltage after the i-1-th compensation parameter acts and the output voltage after the i-th compensation parameter acts; calculate the voltage change value between the output voltage after the i-1-th compensation parameter acts and the output voltage after the i-th compensation parameter acts; Determine whether the voltage change value satisfies the voltage stability verification condition. If the voltage change value satisfies the voltage stability verification condition, continue to use the i+1th compensation parameter for loop compensation; if the voltage change value does not meet the voltage stability verification condition, stop using the i+1th compensation parameter for loop compensation.

Images