WO2022222065A1

WO2022222065A1 - Step-down circuit control method and apparatus, and storage medium

Info

Publication number: WO2022222065A1
Application number: PCT/CN2021/088711
Authority: WO
Inventors: 邓家勇; 刘鹏飞; 刘晓红; 唐建军; 吴壬华
Original assignee: 深圳欣锐科技股份有限公司
Priority date: 2021-04-21
Filing date: 2021-04-21
Publication date: 2022-10-27
Also published as: CN114175480A

Abstract

Disclosed in the present application are a step-down circuit control method and apparatus, and a storage medium. The method comprises: determining an initial output voltage reference value, determining an error signal according to the initial output voltage reference value and an output voltage value of a capacitor, determining a first input signal of a pulse modulation module, and using the error signal as a second input signal of the pulse modulation module; outputting, by means of the pulse modulation module, pulse modulation signals corresponding to the first input signal and the second input signal, the pulse modulation signals being used for adjusting the on-time of the first switching tube and the second switching tube; determining the duty cycle of a first switching tube and the duty cycle of a second switching tube according to the on-time; and adjusting the duty cycle of the first switching tube so that a voltage value of an inductor is less than or equal to an inductance voltage threshold, the inductance voltage threshold being determined according to a circuit current threshold that causes overcurrent protection of a step-down circuit. By adopting the present application, a start current can be effectively reduced, and the stability of a step-down circuit is improved.

Description

Control method, device and storage medium for step-down circuit

technical field

The present application relates to the field of power electronic control, and in particular, to a control method, device and storage medium for a step-down circuit.

Background technique

In the bidirectional step-down circuit, if the traditional method is used to start in bidirectional form, there will be an initial voltage on the capacitor. At this time, the voltage across the inductor is unbalanced, which will cause the inductor to store energy and cause the inductor current to increase. According to the law of electromagnetic induction and Lenz's law, if the voltage across the inductor is always unbalanced, the inductor current will always increase, even as high as 4-7 times the rated current. However, when the circuit starts, the inductor current is too large, which will trigger the overcurrent protection of the circuit, that is, when the circuit current exceeds the circuit current threshold, the device will automatically power off to protect the device, or cause damage to the tube and low circuit stability.

SUMMARY OF THE INVENTION

The embodiments of the present application provide a control method, device and storage medium for a step-down circuit, which can effectively reduce the startup current and improve the stability of the step-down circuit.

A first aspect of an embodiment of the present application provides a method for controlling a step-down circuit, wherein the step-down circuit includes: a first switch tube, a second switch tube, an inductor and a capacitor, and one end of the first switch tube is connected to the second switch respectively One end of the tube and one end of the inductance, the other end of the first switch tube is connected to one end of the input power supply, the other end of the input power supply is respectively connected to the other end of the second switch tube and one end of the capacitor, and the other end of the capacitor Connecting the other end of the above-mentioned inductor, the above-mentioned method includes:

determining an initial output voltage reference value, and determining an error signal according to the initial output voltage reference value and the output voltage value of the capacitor, where the error signal is used to adjust the output voltage value of the capacitor to the initial output voltage reference value;

Determine the first input signal of the pulse modulation module, and use the above-mentioned error signal as the second input signal of the above-mentioned pulse modulation module;

Outputting the pulse modulation signal corresponding to the first input signal and the second input signal through the pulse modulation module, and the pulse modulation signal is used to adjust the conduction time of the first switch tube and the second switch tube;

Determine the duty ratio of the first switch tube and the duty cycle of the second switch tube according to the conduction time of the first switch tube and the second switch tube;

The duty cycle of the first switch is adjusted so that the voltage value of the inductor is less than or equal to the inductor voltage threshold, and the inductor voltage threshold is determined according to the circuit current threshold of the overcurrent protection of the step-down circuit.

With reference to the first aspect, in a possible implementation manner, the above-mentioned determining the initial output voltage reference value includes: determining the above-mentioned initial output voltage reference value according to the output voltage value of the above-mentioned capacitor.

With reference to the first aspect, in a possible implementation manner, the above-mentioned determination of the first input signal of the pulse modulation module includes:

The first input signal of the pulse modulation module is determined according to the initial output voltage reference value and the voltage value of the input power supply.

With reference to the first aspect, in a possible implementation manner, adjusting the duty cycle of the first switch so that the voltage value of the inductor is less than or equal to the inductor voltage threshold value includes:

The duty cycle of the first switch tube is adjusted to a target duty cycle, the target duty cycle is determined by the initial output voltage reference value and the voltage value of the input power supply, and the voltage value of the inductance is determined by the first switch tube. The duty cycle, the above-mentioned initial output voltage reference value, and the above-mentioned voltage value of the input power supply are determined.

With reference to the first aspect, in a possible implementation manner, the above-mentioned initial output voltage reference value is an initial value of zero and is a change value that increases according to the step size; the above-mentioned determination of the initial output voltage reference value includes:

The step size is determined according to the circuit current threshold value and the capacitance value of the capacitor, and the initial output voltage reference value is determined according to the initial value and the step size.

With reference to the first aspect, in a possible implementation manner, the above-mentioned determining the first input signal of the pulse modulation module includes: determining the first input signal of the pulse modulation module as 0.

The duty cycle of the second switch tube is determined to be 0, and the conduction time of the first switch tube is adjusted according to the pulse modulation signal to make the duty cycle of the first switch tube increase according to a specific step size, and the step size is based on The above-mentioned initial output voltage reference value is determined;

Determine the voltage value of the inductor according to the duty cycle of the first switch tube, the initial output voltage reference value, and the voltage value of the input power supply;

When the voltage value of the inductance is less than or equal to the inductance voltage threshold, it is determined that the adjustment of the duty cycle of the first switch tube is completed.

In a second aspect, the present application provides a control device for a step-down circuit. The step-down circuit includes: a first switch tube, a second switch tube, an inductor and a capacitor, and one end of the first switch tube is connected to the second switch respectively. One end of the tube and one end of the inductance, the other end of the first switch tube is connected to one end of the input power supply, the other end of the input power supply is respectively connected to the other end of the second switch tube and one end of the capacitor, and the other end of the capacitor Connecting the other end of the above-mentioned inductor, the above-mentioned device includes:

The first determination module: used to determine an initial output voltage reference value, and determine an error signal according to the initial output voltage reference value and the output voltage value of the capacitor, and the error signal is used to adjust the output voltage value of the capacitor to the initial output. voltage reference;

Second determining module: used to determine the first input signal of the pulse modulation module, and use the above-mentioned error signal as the second input signal of the above-mentioned pulse modulation module;

Pulse modulation module: used to output the pulse modulation signal corresponding to the first input signal and the second input signal, and the pulse modulation signal is used to adjust the conduction time of the first switch tube and the second switch tube;

a third determining module: configured to determine the duty cycle of the first switch tube and the duty cycle of the second switch tube according to the on-time of the first switch tube and the second switch tube adjusted by the pulse modulation module;

The first adjustment module is used to adjust the duty cycle of the first switch tube so that the voltage value of the inductor is less than or equal to the inductor voltage threshold, and the inductor voltage threshold is determined according to the circuit current threshold that causes the overcurrent protection of the step-down circuit.

With reference to the second aspect, in a possible implementation manner, the above-mentioned first determining module is used for:

The initial output voltage reference value is determined according to the output voltage value of the capacitor.

With reference to the second aspect, in a possible implementation manner, the above-mentioned second determination module is used for:

In combination with the second aspect, in a possible implementation manner, the above-mentioned first adjustment module is used for:

With reference to the second aspect, in a possible implementation manner, the above-mentioned initial output voltage reference value is an initial value of zero and is a change value that increases according to the step size, and the above-mentioned first determination module is further configured to:

With reference to the second aspect, in a possible implementation manner, the above-mentioned second determination module is further configured to: determine the first input signal of the above-mentioned pulse modulation module as 0.

In combination with the second aspect, in a possible implementation manner, the above-mentioned first adjustment module is further used for:

In a third aspect, the present application provides a computer device, including: a processor, a memory, and a network interface;

The processor is connected to a memory and a network interface, wherein the network interface is used to provide a data communication function, the memory is used to store program codes, and the processor is used to call the program codes to execute the above-mentioned first in this application. Aspects and methods performed by any of the possible implementations of the first aspect.

In a fourth aspect, the present application provides a computer-readable storage medium, where a computer program is stored in the computer-readable storage medium, and the computer program includes program instructions that, when executed by a processor, execute the above-mentioned first step in the present application. A method performed by an aspect and any possible implementation of the first aspect.

In the present application, by determining the first input signal of the pulse modulation module, and using the error signal as the second input signal of the pulse modulation module, the pulse modulation module outputs the first input signal and the corresponding second input signal. The pulse modulation signal is used to adjust the conduction time of the first switch tube and the second switch tube. The duty cycle of the first switch tube and the duty cycle of the second switch tube are determined according to the conduction time of the first switch tube and the second switch tube, and the duty cycle of the first switch tube is adjusted to the inductance The voltage value is less than or equal to the inductor voltage threshold. Since the inductor voltage threshold is determined according to the circuit current threshold that causes the overcurrent protection of the step-down circuit, using the above control method to start the step-down circuit will not produce excessive voltage. The starting current not only protects the tube from loss, but also improves the stability of the circuit.

Description of drawings

In order to illustrate the technical solutions in the present application more clearly, the following briefly introduces the drawings that are used in the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can also be obtained from these drawings without any creative effort.

1 is a schematic diagram of a bidirectional step-down circuit provided by the present application;

2 is a schematic diagram of an equivalent circuit provided by the present application;

3 is a schematic flowchart of a control method of a step-down circuit provided by the present application;

4 is a schematic diagram of the combination of a control block diagram and a circuit diagram provided by the present application;

5 is a schematic structural diagram of a control device for a step-down circuit provided by the present application;

FIG. 6 is a schematic structural diagram of a computer device provided by the present application.

Detailed ways

The technical solutions in the present application will be clearly and completely described below with reference to the accompanying drawings in the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

The control method of the step-down circuit provided by the present application can be applied to a bidirectional step-down circuit. For the convenience of description, the bidirectional step-down circuit can be directly used as an example for description here. The above-mentioned bidirectional step-down circuit is mainly used in the field of switching power supply. Switching Mode Power Supply (SMPS), also known as switching power supply and switching converter, is a high-frequency power conversion device. Its function is to convert a standard voltage into a subsequent required initial output voltage reference value through different types of main circuits. The switching power supply is also a power supply that uses modern power electronics technology to control the time ratio of the semiconductor power switch tube on and off to maintain a stable output voltage. It is mainly composed of a main circuit, a control module and an auxiliary power supply. Wherein, the above-mentioned auxiliary power supply mainly supplies the above-mentioned main circuit and the above-mentioned control module. In an optional embodiment of the present application, the main circuit may be a bidirectional step-down circuit, and the control module may further include a pulse modulation controller and a proportional-integral controller.

Pulse width modulation (Pulse Width Modulation, PWM) controller, which modulates the bias of the base or gate of the above-mentioned semiconductor power switching device according to the change of the corresponding load, to realize the change of the on-time, so as to realize the duty cycle change. The above-mentioned pulse width modulator is also a very effective controller that uses the digital signal of the microprocessor to control the analog circuit. pulses, use these pulses in place of the sine wave or desired waveform. That is, multiple pulses are generated in a half cycle of the output waveform, so that the equivalent voltage of each pulse is a sine waveform, and the obtained output waveform is smooth and has few low-order harmonics. By modulating the width of each pulse according to certain rules, the output voltage of the circuit can be changed, and the output frequency can also be changed.

The Proportional Integral (PI) controller is mainly used to improve the steady-state performance of the control closed-loop system, which includes a proportional link and an integral link. Among them, the proportional link is proportional to the deviation signal of the control system. Once the deviation occurs, the controller will immediately take control to reduce the deviation. Usually, with the increase of the proportional value, the increase of the overshoot of the closed-loop system will speed up the system response. But when added to a certain level, the system will become unstable. The integral link is mainly used to eliminate the static error and provide the indifference degree of the system. The integral link has two characteristics. One is that the output of the control action is related to the time when the deviation exists. As long as the deviation exists, the output of the integral link will increase with time. , until the deviation is eliminated. The other is that the integral link is slow, and when the deviation just appears, the control effect is very weak, and the influence of the disturbance cannot be overcome in time, resulting in the increase of the dynamic deviation of the adjusted parameters.

Please refer to FIG. 1 , which is a schematic structural diagram of a bidirectional step-down circuit. As shown in FIG. 1 , the above-mentioned bidirectional step-down circuit includes: a first switch tube 021 , a second switch tube 022 , an inductor 03 and a capacitor 04 . One end of the first switch tube 021 is respectively connected to one end of the second switch tube 022 and one end of the inductance 03, the other end of the first switch tube 021 is connected to one end of the input power supply 01, and the other end of the input power supply 01 is respectively connected to the above-mentioned The other end of the second switch tube 022 and one end of the capacitor 04, the other end of the capacitor 04 is connected to the other end of the inductance 03, wherein the first switch tube 021 and the second switch tube 022 can be modulated by the applied pulse width Under the action of the signal, turn-on and turn-off are respectively realized. In an optional embodiment of the present application, the first switch transistor 021 and the second switch transistor 022 may be insulated gate bipolar transistors or power field effect transistors. Insulated Gate Bipolar Transistor (IGBT) has high operating frequency, low required driving power, low switching loss and fast switching speed, which can make the DC buck-boost circuit quickly realize the conversion between buck and boost. . The power FET has fast switching speed, simple driving circuit and high operating frequency. The above-mentioned capacitor 04 can be a filter capacitor to reduce the AC ripple coefficient and smooth the DC output. In the circuit that converts AC to DC power supply, the filter capacitor not only stabilizes the DC output of the power supply, but also reduces the impact of the AC ripple on the circuit. At the same time, it can also absorb the current fluctuations generated during the working process of the circuit and the interference connected in series through the AC power supply, so that the working performance of the circuit is more stable.

Please continue to refer to FIG. 1. As shown in FIG. 1, the bidirectional step-down circuit starts to work. When the first switch tube 021 is turned on and the second switch tube 022 is turned off, the circuit current flows from the left end of the inductor 03 to the inductor. The right end of 03 flows to the capacitor 04. At this time, the inductor 03 and the capacitor 04 are in the energy storage state, and the output voltage of the capacitor 04 is lower than the input voltage of the input power supply 01, completing the step-down function. When the first switch tube 021 is turned off and the second switch tube 022 is turned on, the circuit current flows from the capacitor 04 through the inductor 03 to the second switch tube 022; at this time, the inductor 03 and the capacitor 04 are in the discharge state. state, and the two-way flow of energy is completed. As shown in FIG. 1 , the duty cycle of the first switch tube 021 and the duty cycle of the second switch tube 022 are in a complementary relationship. When the bidirectional step-down circuit starts to work, under the action of the applied pulse width modulation signal, the above-mentioned first A switch tube 021 and a second switch tube 022 are turned on and off respectively, and the input power supply voltage is chopped. After the input voltage is chopped and averaged in one switching cycle, the circuit can be equivalent to the circuit structure shown in Figure 2.

Please refer to FIG. 2. As shown in FIG. 2, if there is an initial voltage on the capacitor 04 when the above circuit is started, and the product of the initial duty cycle and the voltage value of the input power supply 01 is greater than the initial voltage of the capacitor 04, then At this time, the voltage across the inductor is unbalanced, which will make the inductor in a state of energy storage. According to Lenz's law and the law of electromagnetic induction, it can be deduced that the current and voltage of inductor 03 satisfy the following relationship:

From the relationship between the current and voltage of the above-mentioned inductor 03, it can be seen that if the voltage across the inductor is always unbalanced, the inductor current will always increase. Trigger circuit overcurrent protection, reducing the performance of the circuit. In view of the above problems, the present application provides a control method for a step-down circuit, which can effectively reduce the startup current and improve the stability of the step-down circuit.

A method for controlling a step-down circuit, a control device for a step-down circuit, and computer equipment of the present application will be described below with reference to FIGS. 3 to 6 .

Please refer to FIG. 3 , which is a schematic flowchart of a control method of a step-down circuit provided by the present application. A method for controlling a step-down circuit provided by an embodiment of the present application is suitable for a bidirectional step-down circuit, wherein the structure of the above-mentioned bidirectional step-down circuit is shown in the schematic structural diagram shown in FIG. 1 , which is not repeated here. A method for controlling a step-down circuit provided by an embodiment of the present application may include the steps:

S101: Determine an initial output voltage reference value, and determine an error signal according to the initial output voltage reference value and the output voltage value of the capacitor.

In some feasible implementations, please refer to FIG. 4 , which is a schematic diagram of the combination of the control block diagram and the circuit diagram. As shown in FIG. 4 , the output voltage value 075 of the capacitor is used as the initial output voltage reference value 071 . The initial output voltage reference value is the same as the output voltage value of the capacitor, and may also be a voltage value with a deviation within a preset range. Here, the error signal 072 is determined according to the initial output voltage reference value 071 and the output voltage value 075 of the capacitor. The error signal 072 may be determined according to the difference between the initial output voltage reference value 071 and the output voltage value 075 of the capacitor. It can be understood that the error signal 072 obtained here is zero. The above-mentioned error signal 072 is used by the proportional-integral controller 06 in the above-mentioned switching power supply to reduce the deviation between the above-mentioned initial output voltage reference value 071 and the actual output voltage value according to the above-mentioned error signal 072, that is, the output voltage value 075 of the above-mentioned capacitor is adjusted to the above-mentioned initial value. Output voltage reference 071.

S102: Determine the first input signal of the pulse modulation module, and use the above-mentioned error signal as the second input signal of the above-mentioned pulse modulation module.

In some possible implementations, referring to FIG. 4 , the first input signal of the pulse modulation module 05 is determined according to the initial output voltage reference value 071 and the voltage value of the input power supply 01 . Optionally, the value obtained by dividing the above-mentioned initial output voltage reference value 071 by the voltage value of the above-mentioned input power supply 01 is used as the first input signal 073 of the above-mentioned pulse modulation module 05, and the above-mentioned error signal 072 is used as the above-mentioned pulse modulation module 05. Input signal 074. The first input signal 073 and the second input signal are input 074 to the pulse modulation module to output the corresponding pulse modulation signal 076 .

S103, outputting the pulse modulation signal corresponding to the first input signal and the second input signal through the pulse modulation module.

In some possible implementations, referring to FIG. 4 , the pulse modulation module 05 outputs the first input signal 073 and the pulse modulation signal 076 corresponding to the second input signal 074, and the pulse modulation signal 076 is used to adjust the first input signal 076. The conduction time of a switch tube 021 and the above-mentioned second switch tube 022 . The above-mentioned different pulse modulation signals 076 correspond to different high-level pulse widths and different low-level pulse widths, respectively, and the above-mentioned different high-level pulse widths and different low-level pulse widths are used to adjust the conduction of the above-mentioned switch tubes. The on-time and off-time, wherein the high-level pulse width corresponds to the on-time of the switch tube, and the low-level pulse width corresponds to the off-time of the switch tube.

S104: Determine the duty cycle of the first switch transistor and the duty cycle of the second switch transistor according to the on-time of the first switch transistor and the second switch transistor.

In some possible implementations, please refer to FIG. 4 , since the above-mentioned initial output voltage reference 071 is determined as the output voltage value 075 of the capacitor, and the above-mentioned first input signal 073 is the above-mentioned initial output voltage reference value 071 divided by the above-mentioned input power supply 01 The value of the voltage value, the above-mentioned second input signal is the above-mentioned error signal 072 . The above-mentioned error signal 072 is the difference between the above-mentioned initial output voltage reference value 071 and the above-mentioned capacitor output voltage value 075 being zero. Therefore, the above-mentioned pulse modulation module 05 outputs according to the above-mentioned first input signal 073 and the above-mentioned second input signal 074, using The pulse modulation signal 076 for adjusting the on-time of the first switch tube 021 and the second switch tube 022 is determined. Therefore, the duty ratios of the first switch transistor 021 and the second switch transistor 022 can be determined according to the on-time of the first switch transistor 021 and the second switch transistor 022. In addition, the duty cycle of the first switch tube 021 is complementary to the duty cycle of the second switch tube 022 .

S105: Adjust the duty cycle of the first switch tube so that the voltage value of the inductor is less than or equal to the inductor voltage threshold, which is determined according to the circuit current threshold that causes the overcurrent protection of the step-down circuit.

In some feasible implementations, referring to FIG. 4 , the duty cycle of the first switch tube 021 is adjusted to a target duty cycle. The target duty cycle is determined by the initial output voltage reference value 071 and the input power supply 01 . The voltage value is determined. In an optional embodiment of the present application, the target duty cycle here is the above-mentioned initial output voltage reference value 071 divided by the above-mentioned voltage value of the input power supply 01, because the above-mentioned initial output voltage reference value 071 is determined as the above-mentioned capacitor output voltage value 075, it can be understood that the target duty cycle here is the output voltage value 075 of the capacitor divided by the voltage value of the input power supply 01. The voltage value of the inductance 03 is determined by the duty cycle of the first switch tube, the initial output voltage reference value 071 and the voltage value of the input power supply 01 . Specifically, according to the schematic diagram of the circuit structure shown in FIG. 1 , it can be concluded that the voltage value of the above-mentioned inductor 03 is equal to the product of the duty cycle of the above-mentioned first switch tube 021 and the voltage value of the above-mentioned input power supply 01 and then subtracts the above-mentioned initial output voltage. Reference value 071. Since the initial voltage reference value 071 is determined as the output voltage value 075 of the capacitor, the duty cycle of the first switch tube 021 is determined as the output voltage value 04 of the capacitor divided by the voltage value of the input power supply 01. To sum up, we can obtain At this time, the voltage value of the inductor 03 is zero and less than the inductor voltage threshold. The above-mentioned inductor voltage threshold is determined according to the circuit current threshold that causes the above-mentioned overcurrent protection of the buck circuit. Therefore, using this control method can make the starting current of the circuit less than the circuit current threshold that causes the circuit overcurrent protection.

Please continue to refer to FIG. 3. FIG. 3 is a schematic flowchart of a control method of a step-down circuit provided by the present application. The method steps shown in FIG. 3 can also be used for execution in the following embodiments:

In some feasible implementation manners, referring to FIG. 4 , the above-mentioned initial output voltage reference value 071 is determined as an initial value of zero and a change value increased according to the step size, determined according to the above-mentioned circuit current threshold value and the above-mentioned capacitance value of the above-mentioned capacitor 04 The above-mentioned step size, and the above-mentioned initial output voltage reference value 071 is determined according to the above-mentioned initial value and the above-mentioned step size. Optionally, considering that the control speed of the proportional-integral controller 06 is relatively fast, the capacitor output voltage value 075 is controlled by the above-mentioned initial output voltage reference value 071, that is, the capacitor output voltage value 075 is approximately equal to the above-mentioned initial output voltage reference value 071, And the current of the capacitor 04 is equal to the current of the inductor 03, and then according to the relationship between the voltage and current across the capacitor 04:

In the above formula, I _C is the current of the capacitor 04, C is the capacitance of the capacitor 04, and U ₀ is the inductance output voltage value 075; Here, the error signal 072 is determined according to the initial output voltage reference value 071 and the output voltage value 075 of the capacitor. The error signal 072 may be determined according to the difference between the initial output voltage reference value 071 and the output voltage value 075 of the capacitor. The above-mentioned error signal 072 is used by the proportional-integral controller 06 in the above-mentioned switching power supply to reduce the deviation between the above-mentioned initial output voltage reference value 071 and the actual output voltage value according to the above-mentioned error signal 072, that is, the output voltage value 075 of the above-mentioned capacitor is adjusted to the above-mentioned initial value. Output voltage reference value 071.

In some possible implementations, referring to FIG. 4 , the first input signal of the pulse modulation module 05 is determined according to the initial output voltage reference value 071 and the voltage value of the input power supply 01 . Optionally, the first input signal 073 of the pulse modulation module 05 is determined to be 0, and the error signal 072 is used as the second input signal 074 of the pulse modulation module 05 . The first input signal 073 and the second input signal are input 074 to the pulse modulation module to output the corresponding pulse modulation signal 076 .

In some possible implementations, referring to FIG. 4 , the duty cycle of the second switch tube 022 is determined to be 0, and the on-time of the first switch tube 021 is adjusted according to the pulse modulation signal 076 to make the first switch tube 021 turn on. The duty cycle of a switch tube 021 increases according to a specific step size, and the step size is determined according to the above-mentioned initial output voltage reference value 071. As the duty cycle of the first switch tube 021 increases according to a specific step size, the above-mentioned second switch tube 022 The duty cycle of the first switch tube 021 is also in a complementary relationship with the above-mentioned duty cycle of the first switch tube 021 . The voltage value of the inductance 03 is determined according to the duty cycle of the first switch tube 021, the initial output voltage reference value 071 and the voltage value of the input power supply 01. When the voltage value of the inductance 03 is less than or equal to the inductance voltage threshold , the duty cycle adjustment of the first switch tube 021 is completed. Since the inductance voltage threshold is determined according to the circuit current threshold that causes the overcurrent protection of the step-down circuit, and the duty cycle of the second switch tube 022 is determined to be 0, the second switch tube 022 is turned off at this time, and the circuit current of the bidirectional step-down circuit is It cannot flow from the capacitor 04 to the input power supply 01 and can only work in one direction. Since the first switch tube 021 starts from 0 and starts slowly according to a certain step length, this control method can make the starting current of the circuit less than that which causes the circuit overcurrent protection. Circuit current threshold.

Further, please refer to FIG. 5 , which is a schematic structural diagram of a control device of a step-down circuit provided by the present application. The control device of the step-down circuit can be a computer program (including program code) running in the computer equipment, for example, the control device of the step-down circuit is an application software; the control device of the step-down circuit can be used to execute the present invention. The corresponding steps in the method provided by the application. As shown in FIG. 5 , the step-down circuit includes: a first switch tube, a second switch tube, an inductor and a capacitor. One end of the first switch tube is respectively connected to one end of the second switch tube and one end of the inductor. The other end of a switch tube is connected to one end of the input power supply, the other end of the input power supply is respectively connected to the other end of the second switch tube and one end of the capacitor, the other end of the capacitor is connected to the other end of the inductor, and the control device includes: : a first determination module 10 , a second determination module 20 , a pulse modulation module 30 , a third determination module 40 , and a first adjustment module 50 .

A first determination module 10: used to determine an initial output voltage reference value, and determine an error signal according to the initial output voltage reference value and the output voltage value of the capacitor, where the error signal is used to determine the output voltage value of the capacitor adjusting to the initial output voltage reference value;

Second determining module 20: for determining the first input signal of the pulse modulation module, and using the error signal as the second input signal of the pulse modulation module;

Pulse modulation module 30: used to output the first input signal and the pulse modulation signal corresponding to the second input signal, the pulse modulation signal is used to adjust the conduction of the first switch tube and the second switch tube. pass time;

A third determining module 40: configured to determine the duty cycle of the first switch tube and the duty cycle of the second switch tube according to the on-time of the second switch tube adjusted by the pulse modulation module;

The first adjustment module 50 is configured to adjust the duty cycle of the first switch tube so that the voltage value of the inductor is less than or equal to the inductor voltage threshold value, and the inductor voltage threshold value is based on the voltage that causes the overcurrent protection of the step-down circuit. The circuit current threshold is determined.

In a possible implementation manner, the above-mentioned first determining module 10 is used for:

In a possible implementation manner, the above-mentioned second determining module 20 is used for:

In a possible implementation manner, the above-mentioned first adjustment module 50 is used for:

In a possible implementation manner, the above-mentioned initial output voltage reference value is an initial value of zero and is a change value that increases according to the step size, and the above-mentioned first determination module 10 is further configured to:

In a possible implementation manner, the above-mentioned second determining module 20 is further configured to: determine the first input signal of the above-mentioned pulse modulation module as 0.

In a possible implementation manner, the above-mentioned first adjustment module 50 is further used for:

The specific implementation of the first determination module 10 , the second determination module 20 , the pulse modulation module 30 , the third determination module 40 , and the first adjustment module 50 may refer to step S101 - step S101 in the embodiment corresponding to FIG. 3 above. The description of S105 will not be repeated here. In addition, the description of the beneficial effects of using the same method will not be repeated.

Further, please refer to FIG. 6 , which is a schematic structural diagram of the computer device provided by the present application. As shown in FIG. 6 , the computer device 1000 may include: at least one processor 1001 , such as a CPU, at least one network interface 1003 , memory 1004 , and at least one communication bus 1002 . Among them, the communication bus 1002 is used to realize the connection and communication between these components. The network interface 1004 may optionally include a standard wired interface and a wireless interface (eg, a WI-FI interface). The memory 1004 may be a high-speed random access memory (RAM) memory, or may be a non-volatile memory (non-volatile memory), such as at least one disk memory. The memory 1004 can optionally also be at least one storage device located remotely from the aforementioned processor 1001 . As shown in FIG. 6 , the memory 1004 as a computer storage medium may include an operating system, a network communication module, and a device control application program.

In the computer device 1000 shown in FIG. 6, the processor 1001 can be used to call the device control application program stored in the memory 1004 to realize:

In a possible implementation manner, the above-mentioned processor 1001 may be used for:

In a possible implementation manner, the above-mentioned processor 1001 may also be used for:

In a possible implementation manner, the above-mentioned initial output voltage reference value is an initial value of zero and is a change value that increases in steps; the processor 1001 can also be used to:

The step size is determined according to the circuit current threshold value and the capacitance value of the capacitor, and the initial output voltage reference value is determined according to the initial value and the step size;

The error signal is determined according to the initial output voltage reference value and the output voltage value of the capacitor.

In a possible implementation manner, the determining of the first input signal of the pulse modulation module includes: determining the first input signal of the pulse modulation module to be 0.

The duty cycle of the second switch tube is determined to be 0, and the conduction time of the first switch tube is adjusted according to the pulse modulation signal, so that the duty cycle of the first switch tube is increased according to a specific step size, and the step size is based on the above The initial output voltage reference value is determined;

When the voltage value of the inductance is less than or equal to the inductance voltage threshold, the adjustment of the first switch tube is completed.

In addition, it should be pointed out here that: the present application also provides a computer-readable storage medium, and the computer-readable storage medium stores a computer program executed by the control device of the step-down circuit mentioned above, and The computer program includes program instructions, and when the processor executes the program instructions, it can execute the description of the control method for a step-down circuit in the foregoing embodiment corresponding to FIG. 3 , and therefore will not be repeated here. In addition, the description of the beneficial effects of using the same method will not be repeated. For technical details not disclosed in the computer-readable storage medium embodiments involved in the present application, please refer to the description of the method embodiments of the present application. By way of example, program instructions may be deployed to be executed on one computing device, or on multiple computing devices located at one site.

Those of ordinary skill in the art can understand that all or part of the process in the method of the above embodiment can be implemented by instructing the relevant hardware through a computer program, and the above program can be stored in a computer-readable storage medium, and the program is in During execution, it may include the processes of the embodiments of the above-mentioned methods. Wherein, the computer-readable storage medium may be a control device of a step-down circuit provided in any of the foregoing embodiments or an internal storage unit of the above-mentioned device, such as a hard disk or a memory of an electronic device. The computer-readable storage medium can also be an external storage device of the electronic device, such as a pluggable hard disk, a smart media card (SMC), a secure digital (SD) card equipped on the electronic device, Flash card (flash card), etc. The above-mentioned computer-readable storage medium may also include a magnetic disk, an optical disk, a read-only memory (read-only memory, ROM) or a random access memory, and the like. Further, the computer-readable storage medium may also include both an internal storage unit of the electronic device and an external storage device. The computer-readable storage medium is used to store the computer program and other programs and data required by the electronic device. The computer-readable storage medium can also be used to temporarily store data that has been or will be output.

The terms "first", "second" and the like in the claims, description and drawings of the present invention are used to distinguish different objects, rather than to describe a specific order. Furthermore, the terms "comprising" and "having", and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the listed steps or units, but optionally also includes unlisted steps or units, or optionally also includes For other steps or units inherent to these processes, methods, products or devices. Reference herein to an "embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the present invention. The appearance of this phrase in various places in the specification is not necessarily all referring to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments. As used in this specification and the appended claims, the term "and/or" refers to and including any and all possible combinations of one or more of the associated listed items.

Those of ordinary skill in the art can realize that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. Interchangeability, the above description has generally described the components and steps of each example in terms of function. Skilled artisans may implement the described functionality using different methods for each particular application, but such implementations should not be considered beyond the scope of the present invention.

In the embodiments provided in this application, the disclosed circuits and methods may also be implemented in other manners. For example, the device embodiments described above are illustrative. For example, the division of circuit modules is only a logical function division. In actual implementation, there may be other division methods. For example, multiple modules or components may be combined or integrated. to another system, or some features can be ignored, or not implemented.

Each functional unit in each embodiment of the present application may be integrated in one processing unit, or each unit may exist physically alone, or two or more units may be integrated into one unit. The above-mentioned integrated units may be implemented in the form of hardware, or may be implemented in the form of software functional units.

The above disclosures are only the preferred embodiments of the present application, and of course, the scope of the rights of the present application cannot be limited by this. Therefore, equivalent changes made according to the claims of the present application are still within the scope of the present application.

Claims

A control method of a step-down circuit, the step-down circuit comprises: a first switch tube, a second switch tube, an inductor and a capacitor, one end of the first switch tube is respectively connected to one end of the second switch tube and the One end of the inductor, the other end of the first switch tube is connected to one end of the input power supply, the other end of the input power supply is respectively connected to the other end of the second switch tube and one end of the capacitor, and the other end of the capacitor is connected. One end is connected to the other end of the inductor, wherein the method includes:

determining an initial output voltage reference value, and determining an error signal according to the initial output voltage reference value and the output voltage value of the capacitor, where the error signal is used to adjust the output voltage value of the capacitor to the initial output voltage reference value;

determining the first input signal of the pulse modulation module, and using the error signal as the second input signal of the pulse modulation module;

The pulse modulation module outputs the first input signal and the pulse modulation signal corresponding to the second input signal, and the pulse modulation signal is used to adjust the conduction of the first switch tube and the second switch tube time;

determining the duty cycle of the first switch tube and the duty cycle of the second switch tube according to the conduction time of the first switch tube and the second switch tube;

The duty cycle of the first switch tube is adjusted so that the voltage value of the inductor is less than or equal to an inductor voltage threshold, and the inductor voltage threshold is determined according to a circuit current threshold that causes overcurrent protection of the step-down circuit.
The method according to claim 1, wherein the determining an initial output voltage reference value comprises: determining the initial output voltage reference value according to an output voltage value of the capacitor.
The method according to claim 2, wherein the determining the first input signal of the pulse modulation module comprises:

The first input signal of the pulse modulation module is determined according to the initial output voltage reference value and the voltage value of the input power supply.
The method according to claim 3, wherein the adjusting the duty cycle of the first switch tube so that the voltage value of the inductor is less than or equal to an inductor voltage threshold value comprises:

The duty cycle of the first switch tube is adjusted to a target duty cycle, the target duty cycle is determined by the initial output voltage reference value and the voltage value of the input power supply, and the voltage value of the inductor is determined by the The duty cycle of the first switch tube, the initial output voltage reference value and the voltage value of the input power supply are determined.
The method according to claim 1, wherein the initial output voltage reference value is an initial value of zero and is a change value that increases according to a step size; and the determining the initial output voltage reference value comprises:

The step size is determined according to the circuit current threshold, the inductor voltage value and the capacitance value of the capacitor, and the initial output voltage reference value is determined according to the initial value and the step size.
The method according to claim 5, wherein the determining the first input signal of the pulse modulation module comprises: determining the first input signal of the pulse modulation module to be 0.
The method according to claim 6, wherein the adjusting the duty cycle of the first switch so that the voltage value of the inductor is less than or equal to an inductor voltage threshold value comprises:

determining the duty cycle of the second switch tube to be 0, and adjusting the on-time of the first switch tube according to the pulse modulation signal to increase the duty cycle of the first switch tube according to a specific step size, the step size is determined according to the initial output voltage reference value;

Determine the voltage value of the inductor according to the duty cycle of the first switch tube, the initial output voltage reference value and the voltage value of the input power supply;

When the voltage value of the inductor is less than or equal to the voltage threshold of the inductor, it is determined that the duty cycle adjustment of the first switch tube is completed.
A control device for a step-down circuit, characterized in that the step-down circuit comprises: a first switch tube, a second switch tube, an inductor and a capacitor, and one end of the first switch tube is respectively connected to the second switch tube one end of the first switch tube and one end of the inductor, the other end of the first switch tube is connected to one end of the input power supply, and the other end of the input power supply is respectively connected to the other end of the second switch tube and one end of the capacitor, so The other end of the capacitor is connected to the other end of the inductor, and the device includes:

First determination module: used to determine an initial output voltage reference value, and determine an error signal according to the initial output voltage reference value and the output voltage value of the capacitor, where the error signal is used to adjust the output voltage value of the capacitor to the initial output voltage reference value;

Second determining module: for determining the first input signal of the pulse modulation module, and using the error signal as the second input signal of the pulse modulation module;

Pulse modulation module: used to output the first input signal and the pulse modulation signal corresponding to the second input signal, the pulse modulation signal is used to adjust the conduction of the first switch tube and the second switch tube time;

a third determining module: configured to determine the duty cycle of the first switch tube and the duty cycle of the second switch tube according to the on-time of the second switch tube adjusted by the pulse modulation module;

A first adjustment module: used to adjust the duty cycle of the first switch tube so that the voltage value of the inductor is less than or equal to the inductor voltage threshold value, the inductor voltage threshold value is based on the circuit that causes the overcurrent protection of the step-down circuit The current threshold is determined.
A computer device, characterized in that it includes: a processor, a memory, and a network interface;

The processor is connected to a memory and a network interface, wherein the network interface is used to provide a data communication function, the memory is used to store program codes, and the processor is used to call the program codes to execute any one of claims 1-7 method described in item.
A computer-readable storage medium, characterized in that the computer-readable storage medium stores a computer program, the computer program includes program instructions, and when the program instructions are executed by a processor, any one of claims 1-7 is executed. method described in item.