Voltage sampling digital control method, device and equipment of two-phase scb and medium

Abstract

The present application relates to the technical field of power electronic converter, and discloses a voltage sampling digital control method, device and equipment of two-phase SCB and medium, the method comprises the following steps: obtaining the output voltage sampling signal of two-phase SCB converter, and comparing the output voltage sampling signal with reference voltage signal, and generating digital control threshold value;The output voltage sampling signal is sampled periodically, and the digital setting signal is generated according to the digital control threshold value and the output voltage ripple signal obtained by sampling;The main pulse signal is generated according to the digital setting signal and clock reference signal, and the main pulse signal is distributed as two driving signals with a preset phase difference to stagger control the two-phase switching branch of the two-phase SCB converter.The present application simplifies the hardware sampling structure by using only the output voltage sampling signal, and reduces the software control complexity by generating two-phase driving signals through a single digital control path.

Description

Technical Field

[0001] This invention relates to the field of power electronic converter technology, and in particular to a digital control method, apparatus, device and medium for voltage sampling of a two-phase SCB. Background Technology

[0002] With the widespread application of power electronics technology in data centers, electric vehicles, and high-performance computing devices, voltage regulation modules with high power density, high efficiency, and fast dynamic response have become a research hotspot. Two-phase series capacitor buck converters (SCB) have become a preferred solution in intermediate bus architectures due to their unique topology, which distributes the input voltage across the series capacitor, effectively reducing voltage stress on switching devices and improving duty cycle limitations in high buck ratio applications.

[0003] However, existing two-phase SCB converter control schemes suffer from complex sampling structures and high control complexity. Regarding the sampling structure, current technologies primarily employ peak current mode or average current mode control strategies based on current sampling sensors. This typically requires connecting current sampling resistors in series or installing Hall effect sensors in each phase circuit to detect phase current in real time. Simultaneously, it's necessary to monitor the voltage across the series capacitors to achieve capacitor voltage balance. Multiple high-precision current sensors significantly increase material costs and circuit board area, and the introduction of sampling resistors introduces additional conduction losses, reducing overall efficiency. Furthermore, phase current sampling signals are susceptible to noise interference in high-frequency switching environments, requiring complex filtering, conditioning, and anti-interference designs, further increasing hardware design complexity.

[0004] In terms of control complexity, existing technologies require independent current loop regulators for closed-loop control and complex multi-sensor data fusion algorithms to coordinate the operation of each loop in order to achieve accurate current sharing and capacitor voltage balance. Although some existing digital control schemes can achieve closed-loop regulation through processors, digital signal controllers, or field-programmable gate arrays, they still rely on multi-channel current sampling, complex current sharing algorithms, or additional capacitor voltage detection. The control programs are large and difficult to debug, making it difficult to meet the requirements of high power density applications for simplified control architecture. Summary of the Invention

[0005] This invention provides a digital control method, device, equipment, and medium for voltage sampling of a two-phase SCB converter, in order to solve the technical problems of complex sampling structure and high control complexity in existing two-phase SCB converters.

[0006] Firstly, a voltage sampling digital control method for a two-phase SCB is provided, applicable to the digital controller of electronic equipment, including: The output voltage sampling signal of the two-phase SCB converter is acquired, and the output voltage sampling signal is compared with the reference voltage signal to generate a digital control threshold. The output voltage sampling signal is sampled cycle by cycle, and a digital set signal is generated based on the digital control threshold and the sampled output voltage ripple signal. The main pulse signal is generated based on the digital set signal and the clock reference signal, and the main pulse signal is distributed into two drive signals with a preset phase difference to interleave and control the two-phase switching branches of the two-phase SCB converter.

[0007] Secondly, a voltage sampling digital control device for a two-phase SCB is provided, which is applied in the digital controller of electronic equipment, including: A comparison unit is used to acquire the output voltage sampling signal of the two-phase SCB converter, compare the output voltage sampling signal with a reference voltage signal, and generate a digital control threshold. The sampling generation unit is used to sample the output voltage sampling signal cycle by cycle, and generate a digital set signal based on the digital control threshold and the sampled output voltage ripple signal. The generation control unit is used to generate a main pulse signal based on the digital set signal and the clock reference signal, and to distribute the main pulse signal into two drive signals with a preset phase difference, so as to interleave the two-phase switching branches of the two-phase SCB converter.

[0008] Thirdly, an electronic device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the above-described two-phase SCB voltage sampling digital control method.

[0009] Fourthly, a computer-readable storage medium is provided, which stores a computer program that, when executed by a processor, implements the steps of the above-described digital control method for voltage sampling of two-phase SCBs.

[0010] In the above-mentioned scheme implemented by the voltage sampling digital control method, device, equipment, and medium of the two-phase SCB converter, the output voltage sampling signal of the two-phase SCB converter can be acquired, and the output voltage sampling signal can be compared with a reference voltage signal to generate a digital control threshold. The output voltage sampling signal is sampled cycle by cycle, and a digital set signal is generated according to the digital control threshold and the sampled output voltage ripple signal. A main pulse signal is generated according to the digital set signal and the clock reference signal, and the main pulse signal is distributed into two drive signals with a preset phase difference to interleave and control the two-phase switching branches of the two-phase SCB converter. In this invention, the output voltage sampling signal is used as the only feedback, eliminating the need for current sensors and capacitor voltage detection circuits, thus simplifying the hardware sampling structure. Through a single control path from the output voltage sampling signal, digital control threshold, digital set signal to drive signal, two drive signals with a preset phase difference are directly generated, eliminating the need for independent current sharing algorithms and multi-loop coordinated control, reducing the software control complexity, thereby solving the technical problems of complex sampling structure and high control complexity of existing two-phase SCB converters. Attached Figure Description

[0011] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 This is a flowchart illustrating a digital control method for voltage sampling of two-phase SCBs according to an embodiment of the present invention; Figure 2 This is a basic topology diagram of a two-phase SCB converter according to an embodiment of the present invention; Figure 3 A two-phase SCB converter in one embodiment of the present invention , , Equivalent circuit diagrams for the three operating modes; Figure 4 This is a waveform diagram illustrating the control principle of a digital leading-edge valley-controlled two-phase SCB converter according to an embodiment of the present invention. Figure 5 This is a waveform diagram of the output voltage under positive disturbance of a single-voltage sampling digital delay control of a two-phase SCB converter according to an embodiment of the present invention; Figure 6 This is a waveform diagram of the output voltage under positive disturbance of a single-voltage sampling digital non-delay control of a two-phase SCB converter according to an embodiment of the present invention; Figure 7 This is a timing diagram of a leading-edge modulation digital circuit; Figure 8 A waveform diagram of the output voltage positive disturbance of a two-phase SCB converter for digital slope compensation in a single-voltage sampling digital control according to one embodiment of the present invention. Figure 9 This is a schematic block diagram of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0013] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0014] The voltage sampling digital control method for a two-phase SCB provided in this invention can be applied to the digital controller of electronic devices, wherein the electronic devices include a digital controller and a two-phase SCB converter, and the two-phase SCB converter includes a series energy storage network and a two-phase switching branch. Currently, the sampling structure of two-phase SCB converters is complex and the control complexity is high. To address the above problems, this invention proposes a voltage sampling digital control method for a two-phase SCB. This method uses the output voltage sampling signal as the sole feedback, eliminating the need for current sensors and capacitor voltage detection circuits, thus simplifying the hardware sampling structure; through a single control path from the output voltage sampling signal, digital control threshold, digital set signal to the drive signal, two drive signals with a preset phase difference are directly generated, eliminating the need for independent current sharing algorithms and multi-loop coordinated control, reducing the software control complexity, thereby solving the technical problems of complex sampling structure and high control complexity of existing two-phase SCB converters. The invention will be described in detail below through specific embodiments.

[0015] Please see Figure 1 As shown, Figure 1 A flowchart of a voltage sampling digital control method for a two-phase SCB provided in an embodiment of the present invention includes the following steps: S110-S130.

[0016] S110. Obtain the output voltage sampling signal of the two-phase SCB converter, and compare the output voltage sampling signal with the reference voltage signal to generate a digital control threshold. S120. The output voltage sampling signal is sampled cycle by cycle, and a digital set signal is generated based on the digital control threshold and the sampled output voltage ripple signal. S130. Generate a main pulse signal based on the digital set signal and the clock reference signal, and distribute the main pulse signal into two drive signals with a preset phase difference to interleave and control the two-phase switching branches of the two-phase SCB converter.

[0017] In this embodiment, before step S110, the method further includes: analyzing the conduction state of each power switch of the two-phase SCB converter in continuous conduction mode and the charging and discharging law of the series energy storage network; defining a coordinate sequence based on the conduction combination of the main power switches in the two-phase switching branch, wherein the coordinate sequence is used to characterize the three discrete topology operating modes of the series energy storage network, the three discrete topology operating modes including charging state, discharging state, and bypass holding state; establishing a digital leading-edge control strategy between the output voltage sampling signal and the digital control threshold based on the three discrete topology operating modes; and generating a digital set signal according to the digital leading-edge control strategy to control the switching state of the main power switches. It should be noted that... (See also...) Figure 2 , Figure 2 The basic topology diagram of a two-phase SCB converter is shown below. Figure 2 As shown, the two-phase SCB converter includes a DC input voltage. Series capacitor Filter inductor , Output capacitor and the load R, where the output capacitor Using ideal capacitance and equivalent resistance Simulation implementation. The two-phase half-bridge switching device sequentially includes the first switching device. Second switching device Third switching device Fourth switching device Among them, the first switching device With the third switching device Exhibiting complementary conduction characteristics, the second switching device With the fourth switching device It exhibits complementary conduction characteristics, that is When conducting Turn off, When conducting Turn off, series capacitor Connected between two phase arms, it is used to establish an intermediate potential and participate in energy coupling between the two phases. When the circuit reaches steady state, the series capacitor... Based on the principle of charge balance, the midpoint voltage can be automatically clamped to the input voltage. This reduces voltage stress on the switching devices and improves the effective duty cycle in high-dropout applications, placing the input voltage near half of the input voltage. The filter inductor is connected in parallel with the two-phase half-bridge. , With output capacitor The series connection forms the output branch, the load R is connected in parallel at the output terminal, and the output capacitor... Using an ideal capacitor and equivalent resistance The simulation results show that this technology is used to filter out output voltage ripple and maintain stable voltage at the load end.

[0018] It should be further noted that the DC output is connected in parallel with a purely resistive load. For example, let the voltage across the purely resistive load R be the output voltage. And assume the filter inductor , The direction of the reference current is as follows Figure 1 As shown. For ease of explanation, let the voltage at the switching node of the first phase bridge arm be denoted as . The voltage at the switching node of the second phase bridge arm is The inductor current of the first phase is denoted as The second phase inductor current is denoted as The output voltage is sampled using a single output voltage sensor. The output voltage sampling signal is then sent to the digital controller via an ADC. The digital controller compares the output voltage sampling signal with a reference voltage signal to generate a digital control threshold. Understandably, an ADC is an analog-to-digital converter used to convert the sampled output voltage... It is converted into a digital signal and input to the digital controller.

[0019] It should be further explained that the two-phase SCB converter circuit alternately experiences three discrete topology operating modes in steady state: , as well as Corresponding series capacitor The charging, discharging, and holding states of the circuit are analyzed. The on / off logic of each switching device during normal operation of the two-phase SCB circuit is analyzed, and the circuit's operating state is described by the conduction states of the first and second phase half-bridge switching devices. Three operating modes exist, among which... , When on, it is in working mode. , , When on, it is in working mode. , , When on, it is in working mode. The working modal points are arranged in sequence according to To switch the order of the loop. See also Figure 3 , Figure 3 For two-phase SCB converters , , Equivalent circuit diagrams for the three operating modes.

[0020] For ease of understanding, let's take its working mode as an example. Taking the series capacitor charge balance principle as an example, this paper analyzes its role in reducing voltage stress on switching devices and alleviating narrow pulse limitations in high-voltage drop applications. It then analyzes the operating cycle of switching between three discrete topology modes under 180° phase shift modulation, and studies the role of this alternating charge-discharge mechanism in forming an inherent negative feedback loop, correcting phase current imbalance, and achieving sensorless automatic current distribution. For cases where subharmonic oscillations occur within a certain range, the paper derives the ratio of output voltage to input voltage that eliminates subharmonic oscillations, satisfying the following condition. A digital compensation ramp strategy is applied to the digital controller to generate a digital compensation ramp signal, which is then superimposed on the digital control threshold to extend the stable operating range of the system.

[0021] In one embodiment, such as this embodiment, the digital leading-edge control strategy employs a digital leading-edge valley control structure, which includes an outer loop digital voltage loop and an inner loop digital valley determination loop. The outer loop digital voltage loop compares the output voltage sampling signal with the reference voltage signal and generates the digital control threshold after digital compensation calculation. The inner loop digital valley determination loop samples the output voltage sampling signal cycle by cycle and compares the output voltage sampling signal with the digital control threshold. When the falling edge valley of the output voltage sampling signal touches the digital control threshold, a digital set signal is generated. It should be noted that... (See also...) Figure 4 , Figure 4 For digital leading edge type valley value The control principle waveform diagram of the two-phase SCB buck converter is shown below. Figure 4 As shown, For output voltage ripple signal, The valley value control reference voltage is given by `clk`, the digital controller synchronization clock signal is given by `clk`, and the valley value comparison trigger signal is given by `Q`. and This is the drive signal corresponding to the two-phase SCB converter. During each output voltage change cycle, the output voltage ripple surrounds the control reference voltage. Changes occur when the output voltage ripple drops to its lowest point and matches the reference voltage. When the signals intersect, the comparator generates a trigger signal Q. The digital controller calculates the duty cycle based on the current sampling result and updates the DPWM output when the subsequent clock signal arrives, thereby generating the corresponding drive pulse. For a two-phase SCB buck converter, there are two drive signals. and They operate alternately, with a phase difference of half a switching cycle, i.e. Therefore, within a complete switching cycle, the output voltage ripple undergoes a continuous charging and discharging process, forming an output ripple with a frequency twice the switching frequency. (See figure) and These represent the rising slope and falling slope of the output voltage ripple, respectively. By detecting the valley value of the output voltage ripple and updating the duty cycle within the current cycle, the control action can be directly applied to the current switching cycle, thereby eliminating the one-switching-cycle delay present in traditional digital control and improving the system's dynamic response speed and disturbance suppression capability.

[0022] In one embodiment, such as this embodiment, for subharmonic oscillations caused by output voltage disturbances, this embodiment provides a digital slope compensation strategy: a digital compensation slope signal is superimposed on the digital control threshold generated by the outer loop digital voltage loop, so that the disturbance is corrected within a single cycle, thereby suppressing subharmonic oscillations and maintaining the voltage balance of the series capacitor. When a certain switching device is turned on, the corresponding bridge arm of the device can be considered to be in the on state; when it is turned off, the corresponding bridge arm of the device can be considered to be in the off state. Thus, the two-phase series capacitor buck converter can be divided into the following three basic operating states within a complete working cycle: The first operating state is the charging state. In this state, the first phase upper-side switching device... With the second phase lower tube switching device On. At this time, the voltage at the switching node of the first phase bridge arm... for Voltage of the second phase bridge arm switching node =0, series capacitor When in charging state, the voltage of the series capacitor The current in the first phase inductor is trending upwards. Rising, second phase inductor current decline.

[0023] The second operating state is the discharge state. In this state, the second phase upper-side switching device... With the first phase lower tube switching device On. At this time, the voltage at the switching node of the first phase bridge arm... The voltage at the second phase bridge arm switching node is 0. for The series capacitor Ct is in a discharging state, and the voltage across the series capacitor is... The current in the first phase inductor is showing a downward trend; The second phase inductor current decreases. rise.

[0024] The third working state is the hold state. In this state, the first phase lower transistor switching device... With the second phase lower tube switching device On. At this time, the voltage at the switching nodes of the two-phase bridge arms... and All are 0, series capacitor In the holding state, the The basic structure remains unchanged; the inductor current of the first phase remains basically unchanged. The second phase inductor current decreases. It also decreases, and the system is in a free-flowing process.

[0025] As can be seen from the above three operating states, under 180° phase-interleaved driving, the series capacitor In state Charging in the middle, in the state Discharge in the middle, in the state The charging and discharging processes alternate. This alternating charging and discharging mechanism constitutes an inherent negative feedback channel in the topology, which can automatically correct the imbalance of the two-phase current. Therefore, automatic current sharing between the two phases can be achieved without an additional current sampling loop; simultaneously, the series capacitor... Automatic voltage balance is achieved by relying on the charge balance mechanism.

[0026] In one embodiment, such as this embodiment, the digital leading-edge control strategy employs a digital leading-edge valley. Control structure. The outer loop digital voltage loop will output voltage. With reference voltage The comparison is performed, and the control threshold is generated after error amplification. The inner-loop digital valley value determination circuit directly utilizes the output voltage ripple and control threshold. By comparing values, rapid modulation is achieved. The control structure is a dual-loop structure, with the outer digital voltage loop being a slow voltage loop, and the inner digital valley value determination loop directly participating in modulation using the natural ripple of the output voltage.

[0027] Furthermore, at the beginning of each switching cycle, the digital controller initializes the switching state according to a fixed-frequency clock reference, causing the corresponding main switch to enter the off state. Subsequently, during the off period, the output voltage sample value decreases with the ripple; when the output voltage ripple signal intersects with the digital control threshold, the digital controller generates a turn-on trigger signal, causing the corresponding main switch to turn on again. Thus, the turn-on time is determined by the relationship between the output voltage valley sample value and the digital control threshold, achieving digital leading-edge valley control. In this process, the turn-off time is determined by the relationship between the output voltage sample signal and the digital control threshold, and the output voltage drop slope is mainly determined by the ripple voltage drop across the equivalent series resistance of the output capacitor.

[0028] In the two-phase implementation, the modulation pulse generated by the digital valley determination logic is further distributed into two drive signals with a 180° phase difference through the digital PWM module, which act on the first-phase main switching device and the second-phase main switching device respectively, thereby forming a two-phase interleaved drive. The digital controller can ensure a strict 180° phase difference between the two-phase drive signals through PWM phase configuration. Understandably, when a load disturbance causes a momentary drop in output voltage, since the slope of the output voltage drop remains approximately constant for a short period, the output voltage ripple signal will prematurely meet the valley trigger condition corresponding to the digital control threshold. The digital controller detects the trigger condition through the digital valley determination logic and outputs a conduction trigger signal, shortening the turn-off time of the corresponding switching branch and increasing the equivalent duty cycle, thereby suppressing the output voltage drop and achieving rapid dynamic adjustment. Since the output voltage ripple signal directly participates in the digital modulation process, it can respond to load disturbances within a shorter switching cycle, improving closed-loop bandwidth and dynamic performance.

[0029] Furthermore, the static stability boundary of the system is given through a discrete disturbance model: when the voltage conversion ratio satisfy At that time, the system can maintain stability; combined with the SCB converter The relationship can be further used to obtain the duty cycle satisfaction. At this point, the system is within its stable operating range. When the conversion ratio is low, the stability range can be extended by superimposing an external compensation ramp onto the valley reference signal, using a sufficiently large ramp. It can satisfy arbitrarily small .

[0030] Ignore series capacitance The voltage ripple is then: (1) The expression for the steady-state slope at this point is: (2) (3) in, , These represent the switching duty cycles corresponding to two adjacent output voltage changes. At the beginning of each output voltage change cycle, the controller samples the output voltage once and records the results of two adjacent samples as follows: , The digital controller generates the valley voltage control signal through an internal discrete proportional-integral-derivative controller. Since the system's natural frequency is much lower than the switching frequency, it can be approximated that within two adjacent output voltage change cycles... Basically unchanged, that is .

[0031] Output voltage disturbance generated at the beginning of the nth cycle This will be reflected in the sampled values. If no new disturbance occurs within the current period, then... DPWM according to , previous cycle duty cycle The duty cycle of the current period is calculated based on the pre-stored circuit parameters and modulation method in the digital controller. This causes the valley of the output voltage ripple in the nth cycle to be equal to... If they are equal, denote the valley value of the ripple voltage in the nth switching cycle as equal to the valley value of the ripple voltage. ,Depend on Figure 5 We can obtain, (4) From equation (4), the duty cycle algorithm for the two-phase SCB converter with digital valley delay control under leading-edge modulation is: (5) Understandably, in traditional digital delay-type valley voltage control, sampling, calculation, and duty cycle updates all require time. Therefore, the sampled information obtained within the current output voltage change cycle typically cannot immediately apply to the switching action of that cycle, but must be delayed until subsequent cycles. When a load disturbance causes a shift in the output voltage at the start of a cycle, the duty cycle and the on / off times of the switching transistors in the current cycle are predetermined, and the output voltage drop time does not change in real time with the disturbance. Therefore, ideally, the disturbance will approximately persist and propagate to the next output voltage change cycle, meaning the disturbance ratio between adjacent cycles is close to 1. This demonstrates that the delay control method has weak cycle-by-cycle disturbance attenuation capability, limited dynamic response speed, and difficulty in further improving the system's stability margin and transient regulation performance.

[0032] In one embodiment, such as this embodiment, for a digital control circuit, the control process typically includes the following time intervals: sampling time and circuit delay time. Algorithm computation time The algorithm computation time includes the D-PID computation time and DPWM computation time, as well as the time required for duty cycle updates. For the digital valley voltage controlled three-level flying capacitor buck converter described in this invention, we have: To eliminate the control delay of a switching cycle, the key is to maximize the duty cycle update time. This ensures that the digital controller has sufficient time to update the duty cycle. Due to the sampling time and circuit delay time... Primarily determined by the hardware circuit structure, which is usually difficult to change significantly, this invention aims to shorten the algorithm's computation time. ,improve The proportion of the entire control cycle increases the feasibility of overcoming switching cycle delay.

[0033] Figure 6 The control waveforms of a three-level flying capacitor buck converter using the improved digital valley non-delay control strategy under leading-edge modulation are presented. According to... Figure 6 The following relationship can be obtained: (6) The duty cycle algorithm for the improved leading-edge modulated digital valley control two-phase SCB converter can be further obtained as follows: (7) Depend on Figure 6 It can be seen that after a disturbance occurs at the beginning of the nth output voltage change cycle, the improved digital valley voltage control method can adjust the valley value of the output voltage ripple to the preset control target within the nth cycle. This enables a rapid response to disturbances.

[0034] For the timing of digital control circuits under leading-edge modulation, such as Figure 7 As shown, if the timing conditions are met... When the digital controller is in operation, it can complete the duty cycle calculation and update within the current switching cycle, so that the output voltage information sampled in this cycle can directly participate in the modulation process of the current cycle, thereby realizing the improved leading-edge modulation digital valley control algorithm.

[0035] In one embodiment, such as this embodiment, the voltage sampling digital control method for the two-phase SCB in this invention can eliminate the control delay of one output voltage change cycle present in traditional digital control methods, while its stability analysis method remains consistent with traditional digital control algorithms. Specifically, the ratio of the output voltage disturbance in two adjacent output voltage change cycles is defined as: The study will be conducted, and the variation pattern of the disturbance between adjacent periods will be determined using this ratio. Figure 6 The improved digital valley voltage control waveform under the leading-edge modulation method shown can be used to derive the following relationship by combining the geometric relationship between the triangle and the parallelogram in the figure: (8) Stable regions must meet the following requirements Substitute , and The stable region can be obtained as follows (9) In one embodiment, such as this embodiment, a digital ramp variable is set to generate a digital compensation ramp signal. This digital compensation ramp signal is superimposed on the digital control threshold generated by the outer loop digital voltage loop. The digital compensation ramp signal is generated based on the clock reference signal, and its slope is tuned according to the current decrease slope of the output filter inductor of the two-phase SCB converter. The digital ramp variable is reset at the beginning of each switching cycle and incremented by a preset slope within that switching cycle to generate the digital compensation ramp signal. The inner loop digital valley determination loop compares the output voltage sampling signal with the equivalent digital control threshold to determine the conduction time of the two-phase switching branch. The equivalent digital control threshold is generated by superimposing the reference voltage value output by the outer loop digital voltage loop with the digital compensation ramp signal. Understandably, by generating a slope compensation signal within the digital controller and superimposing it onto the valley voltage control signal or the equivalent control quantity used for duty cycle calculation, the propagation relationship of the output voltage disturbance between adjacent cycles can be altered, causing the disturbance to decay cycle by cycle, thereby improving system stability and eliminating subharmonic oscillations. After employing the aforementioned digital slope compensation technology, the control waveform of the leading-edge modulation improved digital valley control two-phase SCB buck converter is as follows: Figure 8 As shown, Let be the slope of the digital slope compensation. We can obtain: (10) Substitution , achievable (11) From equation (11), we can obtain that when ,Right now When, the stability condition is At this point, there is no need to force the addition of slope compensation, and the system can theoretically remain stable without slope compensation.

[0036] In one embodiment, such as this embodiment, current balancing between the two-phase switching branches is achieved through the alternating charge-discharge mechanism of the series energy storage network. The two-phase switching branches include a first-phase switching branch and a second-phase switching branch. The step of achieving current balancing between the two-phase switching branches through the alternating charge-discharge mechanism of the series energy storage network includes: when the current in the first-phase switching branch is too high, the falling slope of the output voltage sampling signal increases, causing the output voltage sampling signal to reach the digital control threshold earlier. The inner-loop digital valley determination loop generates the digital set signal earlier, causing the conduction time of the first-phase switching branch to be advanced. The advanced conduction time of the first-phase switching branch increases the charging time of the capacitor in the series energy storage network, and the terminal voltage of the capacitor increases. When the second phase switch branch is turned on, the energy released by the series energy storage network increases, reducing the descent slope of the output voltage sampling signal. This delays the output voltage sampling signal reaching the digital control threshold, and the inner loop digital valley determination loop delays generating the digital set signal, thus delaying the turn-on time of the second phase switch branch. By adjusting the turn-on time, the charging and discharging times of the two phase switch branches tend to be balanced, correcting the two-phase current imbalance and maintaining the midpoint potential of the series energy storage network at a preset value. Understandably, the above adjustment process is entirely based on changes in the output voltage sampling signal. Through a negative feedback causal chain of changes in the descent slope, the threshold time, and the turn-on time adjustment, current balancing of the two phase switch branches and voltage balancing of the series energy storage network can be achieved without current sensors and capacitor voltage detection circuits, simplifying the hardware sampling structure and reducing control complexity.

[0037] In one embodiment, such as this embodiment, if the output voltage sampling signal does not trigger a signal that touches the digital control threshold within a preset maximum shutdown time, a forced turn-on signal is triggered, wherein the preset maximum shutdown time is greater than the switching cycle; if the turn-on signal is triggered after a timeout, a fault flag is generated, which is used to increase the forced turn-on bias in subsequent cycles and is automatically cleared after several consecutive cycles without a timeout. Understandably, through the above watchdog protection mechanism, when there are sudden load changes, input voltage fluctuations, or abnormalities in the digital control logic, the output voltage can be prevented from running out of control due to prolonged shutdown of the switching transistor, thus improving system reliability; the adaptive bias adjustment of the fault flag provides protection margin during the duration of the abnormality, while the automatic clearing mechanism avoids protection state lock-in, ensuring that the system quickly resumes normal operation after the abnormality is eliminated. It should be noted that the preset maximum shutdown time of the watchdog timer is 1.2 to 1.5 times the switching cycle T.

[0038] In one embodiment, a voltage sampling digital control device for a two-phase SCB is provided, which corresponds one-to-one with the voltage sampling digital control method for a two-phase SCB described in the above embodiments. The voltage sampling digital control device for the two-phase SCB includes an acquisition and comparison unit, a sampling generation unit, and a generation control unit. Detailed descriptions of each functional module are as follows: A comparison unit is used to acquire the output voltage sampling signal of the two-phase SCB converter, compare the output voltage sampling signal with a reference voltage signal, and generate a digital control threshold. The sampling generation unit is used to sample the output voltage sampling signal cycle by cycle, and generate a digital set signal based on the digital control threshold and the sampled output voltage ripple signal. The generation control unit is used to generate a main pulse signal based on the digital set signal and the clock reference signal, and to distribute the main pulse signal into two drive signals with a preset phase difference, so as to interleave the two-phase switching branches of the two-phase SCB converter.

[0039] The voltage sampling digital control device for the aforementioned two-phase SCB can be implemented as a computer program, which can, for example... Figure 9 It runs on the electronic device shown.

[0040] Please see Figure 9 , Figure 9 This is a schematic block diagram of an electronic device provided in an embodiment of the present invention. The electronic device 300 is a device capable of digitally controlling the voltage sampling of two-phase SCBs.

[0041] See Figure 9 The electronic device 300 includes a processor 302, a memory, and a network interface 305 connected via a system bus 301. The memory may include a non-volatile storage medium 303 and internal memory 304.

[0042] The non-volatile storage medium 303 can store an operating system 3031 and a computer program 3032. When the computer program 3032 is executed, it causes the processor 302 to execute a voltage sampling digital control method for a two-phase SCB.

[0043] The processor 302 provides computing and control capabilities to support the operation of the entire electronic device 300.

[0044] The internal memory 304 provides an environment for the operation of the computer program 3032 in the non-volatile storage medium 303. When the computer program 3032 is executed by the processor 302, the processor 302 can execute a voltage sampling digital control method for a two-phase SCB.

[0045] This network interface 305 is used for network communication with other devices. Those skilled in the art will understand that... Figure 9 The structure shown is merely a block diagram of a portion of the structure related to the present invention and does not constitute a limitation on the electronic device 300 to which the present invention is applied. The specific electronic device 300 may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0046] The processor 302 is used to run a computer program 3032 stored in a memory to implement any embodiment of the voltage sampling digital control method for the two-phase SCB described above.

[0047] It should be understood that, in this embodiment of the invention, the processor 302 may be a Central Processing Unit (CPU), or it may be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor.

[0048] It will be understood by those skilled in the art that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a storage medium, which is a computer-readable storage medium. The computer program is executed by a processor in the computer system to implement the process steps of the embodiments of the above methods.

[0049] Therefore, the present invention also provides a storage medium. This storage medium can be a computer-readable storage medium. The storage medium stores a computer program. When executed by a processor, the computer program causes the processor to perform any embodiment of the voltage sampling digital control method for the two-phase SCB described above.

[0050] The storage medium can be any computer-readable storage medium capable of storing program code, such as a USB flash drive, portable hard drive, read-only memory (ROM), magnetic disk, or optical disk.

[0051] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0052] In the several embodiments provided by this invention, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative. For example, the division of each unit is merely a logical functional division, and there may be other division methods in actual implementation. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed.

[0053] The steps in the method of this invention can be adjusted, merged, or reduced in order according to actual needs. The units in the device of this invention can be merged, divided, or reduced according to actual needs. Furthermore, the functional units in the various embodiments of this invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0054] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause an electronic device to execute all or part of the steps of the methods described in the various embodiments of the present invention.

[0055] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0056] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Since these modifications and variations fall within the scope of the claims and their equivalents, this invention also intends to include these modifications and variations.

[0057] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A voltage sampling digital control method for a two-phase SCB, applied in the digital controller of electronic equipment, characterized in that, include: The output voltage sampling signal of the two-phase SCB converter is acquired, and the output voltage sampling signal is compared with the reference voltage signal to generate a digital control threshold. The output voltage sampling signal is sampled cycle by cycle, and a digital set signal is generated based on the digital control threshold and the sampled output voltage ripple signal. The main pulse signal is generated based on the digital set signal and the clock reference signal, and the main pulse signal is distributed into two drive signals with a preset phase difference to interleave and control the two-phase switching branches of the two-phase SCB converter. Prior to the step of acquiring the output voltage sampling signal of the two-phase SCB converter, the method further includes: The conduction state of each power switch of the two-phase SCB converter and the charging and discharging law of the series energy storage network are analyzed in continuous conduction mode. A coordinate sequence is defined based on the conduction combination of the main power switch in the two-phase switching branch. The coordinate sequence is used to characterize the three discrete topology operating modes of the series energy storage network, which include charging state, discharging state and bypass holding state. Based on the three discrete topology operating modes, a digital leading-edge control strategy is established between the output voltage sampling signal and the digital control threshold. The digital set signal is generated according to the digital leading-edge control strategy to control the switching state of the main power switch.

2. The voltage sampling digital control method for two-phase SCB as described in claim 1, characterized in that, The digital leading-edge control strategy employs a digital leading-edge valley control structure, which includes an outer digital voltage loop and an inner digital valley determination loop. The outer digital voltage loop compares the output voltage sampling signal with the reference voltage signal and generates the digital control threshold after digital compensation calculation. The inner digital valley determination loop samples the output voltage sampling signal cycle by cycle and compares the output voltage sampling signal with the digital control threshold. When the falling edge valley of the output voltage sampling signal touches the digital control threshold, the digital set signal is generated.

3. The voltage sampling digital control method for two-phase SCB as described in claim 2, characterized in that, The alternating charging and discharging mechanism of the series energy storage network achieves current balance between the two-phase switching branches, wherein the two-phase switching branches include a first-phase switching branch and a second-phase switching branch. The step of achieving current balancing between the two-phase switch branches through the alternating charge and discharge mechanism of the series energy storage network includes: When the current in the first phase switch branch is too large, the falling slope of the output voltage sampling signal increases, causing the output voltage sampling signal to reach the digital control threshold earlier. The inner loop digital valley determination loop generates the digital set signal earlier, thus advancing the conduction time of the first phase switch branch. The earlier conduction time of the first phase switch branch increases the charging time of the capacitor in the series energy storage network, and the terminal voltage of the capacitor increases. When the second phase switch branch is turned on, the energy released by the series energy storage network increases, which reduces the falling slope of the output voltage sampling signal, delays the output voltage sampling signal from reaching the digital control threshold, and delays the generation of the digital set signal by the inner loop digital valley determination loop, thus delaying the turn-on time of the second phase switch branch. By adjusting the conduction time, the charging and discharging times of the two-phase switch branches are made more balanced, so as to correct the imbalance of the two-phase current and maintain the midpoint potential of the series energy storage network as a preset value.

4. The voltage sampling digital control method for two-phase SCB as described in claim 3, characterized in that, A digital ramp variable is set to generate a digital compensation ramp signal. The digital compensation ramp signal is superimposed on the digital control threshold generated by the outer loop digital voltage loop. The digital compensation ramp signal is generated according to the clock reference signal, and its slope is tuned according to the current drop slope of the output filter inductor of the two-phase SCB converter.

5. The voltage sampling digital control method for two-phase SCB as described in claim 4, characterized in that, At the beginning of each switching cycle, the digital ramp variable is reset, and during the switching cycle, the digital ramp variable is incremented according to a preset slope to generate the digital compensation ramp signal. The inner loop digital valley determination loop compares the output voltage sampling signal with the equivalent digital control threshold to determine the conduction time of the two-phase switching branch. The equivalent digital control threshold is generated by superimposing the reference voltage value output by the outer loop digital voltage loop with the digital compensation ramp signal.

6. The voltage sampling digital control method for two-phase SCB as described in claim 1, characterized in that, If the output voltage sampling signal does not trigger a signal that touches the digital control threshold within the preset maximum shutdown time, a forced turn-on signal is triggered, wherein the preset maximum shutdown time is greater than the switching cycle; if the turn-on signal is triggered after a timeout, a fault flag is generated, which is used to increase the forced turn-on bias in subsequent cycles and is automatically cleared after several consecutive cycles without a timeout.

7. A voltage sampling digital control device for a two-phase SCB, applied in the digital controller of electronic equipment, characterized in that, include: A comparison unit is used to acquire the output voltage sampling signal of the two-phase SCB converter, compare the output voltage sampling signal with a reference voltage signal, and generate a digital control threshold. The sampling generation unit is used to sample the output voltage sampling signal cycle by cycle, and generate a digital set signal based on the digital control threshold and the sampled output voltage ripple signal. A generation control unit is used to generate a main pulse signal based on the digital set signal and the clock reference signal, and to distribute the main pulse signal into two drive signals with a preset phase difference, so as to interleave the two-phase switching branches of the two-phase SCB converter. Prior to the step of acquiring the output voltage sampling signal of the two-phase SCB converter, the method further includes: The conduction state of each power switch of the two-phase SCB converter and the charging and discharging law of the series energy storage network are analyzed in continuous conduction mode. A coordinate sequence is defined based on the conduction combination of the main power switch in the two-phase switching branch. The coordinate sequence is used to characterize the three discrete topology operating modes of the series energy storage network, which include charging state, discharging state and bypass holding state. Based on the three discrete topology operating modes, a digital leading-edge control strategy is established between the output voltage sampling signal and the digital control threshold. The digital set signal is generated according to the digital leading-edge control strategy to control the switching state of the main power switch.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the voltage sampling digital control method for a two-phase SCB as described in any one of claims 1 to 6.

9. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the voltage sampling digital control method for the two-phase SCB as described in any one of claims 1 to 6.

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