Anti-disturbance method based on virtual capacitive load

Abstract

The invention provides an anti-disturbance method based on a virtual capacitive load, and the method comprises the steps: constructing an initial equivalent circuit corresponding to a power converter, and the initial equivalent circuit is used for describing a circuit when the output end of the power converter supplies power to an actual load; adding a virtual capacitive load into the initial equivalent circuit to obtain a target equivalent circuit, wherein the virtual capacitive load is connected in parallel to two ends of an actual load in the equivalent circuit; based on the target equivalent circuit, a transfer function corresponding to the actual load changed through the virtual capacitive load is determined, and the transfer function is used for describing the ratio of the load voltage at the two ends of the actual load to the load current flowing into the actual load; and when it is actually detected that disturbance occurs in the load voltage at the two ends of the actual load, the influence of disturbance on the load voltage is reduced by changing the load current flowing into the actual load based on the transfer function.

Description

Technical Field

[0001] The present application relates to the field of power electronics technology, and in particular to an anti-disturbance method based on a virtual capacitive load. Background Art

[0002] At present, the output end of a voltage source type DC-to-DC converter or DC-AC converter using pulse width modulation (PWM) is generally connected to a filter circuit, which includes a filter impedance and a filter capacitor to filter out the switching ripple. The filter capacitor can also achieve the purpose of resisting load interference. When the voltage across the load fluctuates greatly, an additional filter capacitor is required to achieve a stronger anti-interference ability. Adding an additional filter capacitor to the filter circuit will increase the cost. Summary of the invention

[0003] In view of this, the purpose of the present application is to provide at least a disturbance resistance method based on a virtual capacitive load, by constructing an initial equivalent circuit connected to a power converter, and adding a virtual capacitive load connected in parallel at both ends of the actual load to the initial equivalent circuit to obtain a target equivalent circuit, and constructing a transfer function of the ratio of the load voltage corresponding to the voltage at both ends of the actual load to the load current flowing through the actual load through the target equivalent circuit, and then, when it is determined that there is a fluctuation in the voltage at both ends of the actual load, the load current flowing into the actual load is changed through the transfer function to stabilize the load voltage region, thereby solving the technical problem in the prior art that an additional actual capacitor needs to be set to reduce the fluctuation in the voltage at both ends of the load, thereby achieving the technical effect of improving the stability of power supply.

[0004] This application mainly includes the following aspects:

[0005] In a first aspect, an embodiment of the present application provides an anti-disturbance method based on a virtual capacitive load, the method comprising: constructing an initial equivalent circuit corresponding to a power converter, the initial equivalent circuit being used to describe a circuit when the output end of the power converter supplies power to an actual load; adding a virtual capacitive load to the initial equivalent circuit to obtain a target equivalent circuit, the virtual capacitive load being connected in parallel to both ends of the actual load in the equivalent circuit; based on the target equivalent circuit, determining a transfer function corresponding to the actual load changed by the virtual capacitive load, the transfer function being used to describe a ratio of a load voltage at both ends of the actual load to a load current flowing into the actual load; when a disturbance is actually detected in the load voltage at both ends of the actual load, reducing the impact of the disturbance on the load voltage by changing the load current flowing into the actual load based on the transfer function.

[0006] Optionally, the initial equivalent circuit refers to a circuit equivalent to the actual load connected to the output end of the power converter through a filtering circuit, the filtering circuit includes a filtering impedance and a filtering capacitor, wherein the target equivalent circuit includes: a voltage source equivalent to the power converter; an equivalent impedance, one end of the equivalent impedance is connected to one end of the voltage source, and the equivalent impedance is equivalent to the filtering impedance on the filtering circuit and the line impedance of the circuit where the power converter is located; a virtual capacitive load, one end of the virtual capacitive load is connected to the other end of the equivalent impedance, and the other end of the virtual capacitive load is connected to the other end of the voltage source; the actual load and the filtering capacitor of the filtering circuit, the actual load and the filtering capacitor are connected in parallel at both ends of the virtual capacitive load.

[0007] Optionally, the first output current flowing out of the equivalent impedance in the target equivalent circuit is equal to the virtual current flowing through the virtual capacitive load and the second output current, the second output current is used to indicate the current output by the filter impedance, and the second output current is equal to the capacitive current flowing into the filter capacitor and the load current flowing through the actual load.

[0008] Optionally, the transfer function corresponding to the actual load is determined in the following manner: based on the target equivalent circuit, a control block diagram corresponding to the target equivalent circuit is constructed by introducing a proportional-integral controller, a current loop, a load voltage feedback and a virtual capacitive load feedback, and the transfer function is determined.

[0009] Optionally, the transfer function corresponding to the actual load is determined in the following manner: the first output current is determined by comparing the expected voltage of the voltage source with the load voltage across the actual load through the proportional-integral controller; the second output current is determined by the closed-loop gain of the current loop based on the first output current and the virtual current flowing through the virtual capacitive load; the transfer function is constructed based on the transfer function of the proportional-integral controller, the closed-loop gain and the current flow trend of the second output current.

[0010] Optionally, the closed-loop gain is used to control the relationship between the second output current and the difference between the first output current and the virtual current.

[0011] Optionally, the virtual capacitive load is used to indicate a virtual capacitive load introduced into a first-order low-pass filter.

[0012] Optionally, the load current flowing into the actual load is changed in the following manner: the second output current is changed according to the transfer function to change the load current flowing into the actual load.

[0013] Optionally, the method also includes: gradually increasing the capacitance value of the virtual capacitive load of the target equivalent circuit, and obtaining a Bode diagram corresponding to each virtual capacitive load, the Bode diagram being used to describe the amplitude corresponding to the interference signal for the same frequency range; determining a target Bode diagram corresponding to which the amplitudes within the frequency range are all less than zero; and using the virtual capacitive load corresponding to the target Bode diagram as an enhanced capacitor to set the enhanced capacitor in the filtering circuit.

[0014] In the second aspect, an embodiment of the present application also provides an anti-disturbance device based on a virtual capacitive load, the device comprising: a first equivalent module, constructing an initial equivalent circuit corresponding to a power converter, the initial equivalent circuit being used to describe the circuit when the output end of the power converter supplies power to an actual load; a second equivalent module, adding a virtual capacitive load to the initial equivalent circuit to obtain a target equivalent circuit, the virtual capacitive load being connected in parallel to both ends of the actual load in the equivalent circuit; a determination module, based on the target equivalent circuit, determining a transfer function corresponding to the actual load changed by the virtual capacitive load, the transfer function being used to describe the ratio of the load voltage at both ends of the actual load to the load current flowing into the actual load; an adjustment module, when a disturbance is actually detected in the load voltage at both ends of the actual load, changing the load current flowing into the actual load based on the transfer function to reduce the impact of the disturbance on the load voltage.

[0015] An anti-disturbance method based on a virtual capacitive load is provided in an embodiment of the present application. The method includes: constructing an initial equivalent circuit corresponding to a power converter, the initial equivalent circuit is used to describe the circuit when the output end of the power converter supplies power to an actual load; adding a virtual capacitive load to the initial equivalent circuit to obtain a target equivalent circuit, the virtual capacitive load is connected in parallel to both ends of the actual load in the equivalent circuit; based on the target equivalent circuit, determining a transfer function corresponding to the actual load changed by the virtual capacitive load, the transfer function is used to describe the ratio of the load voltage at both ends of the actual load to the load current flowing into the actual load; when a disturbance is actually detected in the load voltage at both ends of the actual load, changing the load current flowing into the actual load based on the transfer function to reduce the impact of the disturbance on the load voltage. An initial equivalent circuit connected to a power converter is constructed, and a target equivalent circuit is obtained by adding a virtual capacitive load connected in parallel at both ends of the actual load to the initial equivalent circuit. A transfer function of the ratio of the load voltage corresponding to the voltage at both ends of the actual load to the load current flowing through the actual load is constructed through the target equivalent circuit. Furthermore, when it is determined that the voltage at both ends of the actual load fluctuates, the load current flowing into the actual load is changed through the transfer function of the load voltage to stabilize the load voltage region. This solves the technical problem in the prior art that an additional actual capacitor needs to be set to reduce the fluctuation of the voltage at both ends of the load, thereby achieving the technical effect of improving the stability of power supply.

[0016] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 A schematic diagram showing a power converter connected to a filter circuit in the prior art provided by an embodiment of the present application is shown.

[0019] Figure 2 A flow chart of an anti-disturbance method based on a virtual capacitive load provided in an embodiment of the present application is shown.

[0020] Figure 3 A control block diagram of a dual closed-loop control in the prior art provided by an embodiment of the present application is shown.

[0021] Figure 4 A circuit diagram of an initial equivalent circuit corresponding to the dual closed-loop control in the prior art provided by an embodiment of the present application is shown.

[0022] Figure 5 A circuit diagram of a target equivalent circuit provided by an embodiment of the present application is shown.

[0023] Figure 6 A control block diagram corresponding to a target equivalent circuit provided in an embodiment of the present application is shown.

[0024] Figure 7 A control block diagram corresponding to another target equivalent circuit provided in an embodiment of the present application is shown.

[0025] Figure 8 The Bode diagram corresponding to the case where no virtual capacitive load is provided in the embodiment of the present application is shown.

[0026] Fig. 9 The Bode diagram corresponding to the setting of the virtual capacitive load provided in the embodiment of the present application is shown.

[0027] Fig.10 A functional module diagram of an anti-disturbance device based on a virtual capacitive load provided in an embodiment of the present application is shown.

[0028] Fig.11 A schematic structural diagram of an electronic device provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0029] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It should be understood that the drawings in the present application only serve the purpose of explanation and description and are not used to limit the scope of protection of the present application. In addition, it should be understood that the schematic drawings are not drawn in real proportion. The flowchart used in this application shows the operations implemented according to some embodiments of the present application. It should be understood that the operations of the flowchart can be implemented out of sequence, and the steps without logical context can be reversed in order or implemented simultaneously. In addition, those skilled in the art, under the guidance of the content of the present application, can add one or more other operations to the flowchart, or remove one or more operations from the flowchart.

[0030] In addition, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0031] In the prior art, the output end of DC-DC or DC-AC needs to be connected to a filter circuit to filter out the switching ripple. The filter circuit includes a filter impedance and a filter capacitor. Figure 1 , Figure 1 This is a schematic diagram of a power converter connected to a filter circuit in the prior art provided by an embodiment of the present application. Figure 1 As shown, the power converter 101 is a DC-DC or DC-AC, and the filter circuit 102 connected to the output end of the power converter includes a filter impedance L and a filter capacitor C f , one end of the filter impedance L is connected to the output end of the power converter, and the other end of the filter impedance L is connected to the filter capacitor C f The actual load Z is connected to the connection between the filter impedance L and the filter capacitor. load One end of the filter capacitor C f The other end and the actual load Z load The other end is grounded. Furthermore, when the voltage across the load fluctuates, an additional capacitor needs to be connected in parallel across the filter capacitor to increase the anti-interference capability, which increases the cost.

[0032] Based on this, the embodiment of the present application provides an anti-disturbance method based on a virtual capacitive load, by constructing an initial equivalent circuit connected to a power converter, and adding a virtual capacitive load connected in parallel at both ends of the actual load to the initial equivalent circuit to obtain a target equivalent circuit, and constructing a transfer function corresponding to the voltage at both ends of the actual load through the target equivalent circuit. Then, when it is determined that the voltage at both ends of the actual load fluctuates, the current output by the filter impedance in the equivalent circuit is changed through the transfer function to change the load current flowing into the actual load, so as to suppress the fluctuation of the output voltage with the disturbance amount, so as to stabilize the load voltage region, solve the technical problem that an additional actual capacitor needs to be set in the prior art to reduce the voltage fluctuation at both ends of the load, and achieve the technical effect of improving the stability of power supply, which is as follows:

[0033] See also Figure 2 , Figure 2 The flowchart of an anti-disturbance method based on a virtual capacitive load provided in an embodiment of the present application. Figure 2As shown, the anti-disturbance method based on virtual capacitive load provided in the embodiment of the present application includes the following steps:

[0034] S101: Construct an initial equivalent circuit corresponding to the power converter.

[0035] The power converter may be a DC-DC converter or a DC-AC converter, and the initial equivalent circuit is used to describe the circuit when the output end of the power converter supplies power to the actual load. Specifically, the initial equivalent circuit refers to the circuit equivalent to the output end of the power converter being connected to the actual load through a filter circuit, and the filter circuit includes a filter impedance and a filter capacitor.

[0036] Specifically, the output end of the power converter includes a first output end and a second output end, the first output end of the power converter is connected to one end of the filter impedance, the other end of the filter impedance is respectively connected to one end of the filter capacitor and one end of the actual load, and the second output end of the power converter is respectively connected to the other end of the filter capacitor and the other end of the actual load.

[0037] That is to say, the power converter provides power to the actual load through the filter capacitor. The power converter generally adopts a double closed-loop control structure with a voltage outer loop and a current inner loop. Figure 3 , Figure 3 This is a control block diagram of the dual closed-loop control in the prior art provided by the embodiment of the present application. Figure 3 As shown, u ref Refers to the expected voltage of the voltage loop, which is equivalent to the expected output voltage output by the power converter, v c Refers to the load voltage across the actual load. c and the desired output voltage u ref The comparison result is passed through the proportional integral PI controller to obtain the expected impedance current i output by the filter impedance. Lref , the actual impedance current i output by the filter impedance is obtained through the Gcur(s) current closed loop L , the actual impedance current i L The output current i flowing into the actual load o The difference flows into the filter capacitor C f , filter capacitor C f The voltage across the two ends is the same as the load voltage across the actual load. Therefore, when the virtual capacitive load is not set, the transfer function corresponding to the load voltage describes the ratio of the load voltage to the load current when the load current is disturbed. The transfer function is Among them, v c (s) refers to the load voltage across the actual load; i o (s) refers to the load current flowing through the actual load; sCf refers to the impedance of the filter capacitor; PI(s) refers to the transfer function of the proportional-integral controller, K p Refers to the proportional gain, K i refers to the integral gain, s refers to the Laplace operator; G cur (s) refers to the closed-loop gain of the current loop.

[0038] Further, see Figure 4 , Figure 4 The circuit diagram is a circuit diagram of the initial equivalent circuit corresponding to the double closed-loop control in the prior art provided by the embodiment of the present application. Figure 4 As shown, the power converter added to the control loop is equivalent to a voltage source u ref The sum of the filter impedance of the filter circuit and the line impedance on the actual circuit is taken as the equivalent impedance Z eq , and thus, the current flowing out of the equivalent impedance is equivalent to the actual impedance current i L And flows to the filter capacitor C f and the actual load Z load , flows through the filter capacitor C f The current is marked as i c , flows through the actual load Z load The current is the output current io, and the voltage across the filter capacitor is equal to the voltage across the actual load.

[0039] S102: Adding a virtual capacitive load to the initial equivalent circuit to obtain a target equivalent circuit.

[0040] Wherein, the virtual capacitive load is connected in parallel to both ends of the actual load in the equivalent circuit. Figure 5 , Figure 5 This is a circuit diagram of the target equivalent circuit provided by the embodiment of the present application. Figure 5 As shown, the target equivalent circuit includes: the voltage source u equivalent to the power converter ref ; Equivalent impedance Z eq , one end of the equivalent impedance is connected to one end of the voltage source, and the equivalent impedance is equivalent to the filter impedance on the filter circuit and the line impedance of the circuit where the power converter is located; a virtual capacitive load C v , one end of the virtual capacitive load is connected to the other end of the equivalent impedance, and the other end of the virtual capacitive load is connected to the other end of the voltage source; the actual load Z load and the filter capacitor C of the filter circuit f , the actual load and the filter capacitor are connected in parallel at both ends of the virtual capacitive load.

[0041] The virtual capacitive load is represented by a capacitor in the target equivalent circuit. The first output current i flowing out of the equivalent impedance in the target equivalent circuit Lref is equal to the virtual current i flowing through the virtual capacitive load Cv and the second output current i L , the second output current is used to indicate the current output by the filter impedance, and the second output current is equal to the capacitive current i flowing into the filter capacitor C and the load current i flowing through the actual load o .

[0042] That is to say, the first output current i output by the equivalent impedance Lref The virtual current i of the virtual capacitive load needs to be subtracted Cv Then it will flow into the filter capacitor and the actual load, and because the virtual capacitive load is connected in parallel across the actual load, the voltages across the virtual capacitive load, the filter capacitor and the actual load are equal.

[0043] S103: Based on the target equivalent circuit, determining a transfer function corresponding to changing the actual load through the virtual capacitive load;

[0044] The transfer function is used to describe the ratio of the load voltage across the actual load to the load current flowing into the actual load.

[0045] The transfer function corresponding to the actual load is determined in the following manner: based on the target equivalent circuit, a control block diagram corresponding to the target equivalent circuit is constructed by introducing a proportional-integral controller, a current loop, a load voltage feedback and a virtual capacitive load feedback, and the transfer function is determined.

[0046] Specifically, the transfer function corresponding to the actual load is determined in the following manner: the first output current is determined by comparing the expected voltage of the voltage source with the load voltage at both ends of the actual load through the proportional-integral controller; the second output current is determined by the closed-loop gain of the current loop based on the first output current and the virtual current flowing through the virtual capacitive load; the transfer function is constructed based on the transfer function of the proportional-integral controller, the closed-loop gain and the current flow trend of the second output current.

[0047] Among them, the proportional-integral controller is used to perform proportional-integral operation on the result of load voltage feedback and the expected voltage of the voltage source to obtain a first output current, and use the first output current as an input value of the current loop, and obtain the current flowing through the virtual capacitive load through virtual capacitive load feedback, and use the current flowing through the virtual capacitive load as another input value of the current loop, and obtain the current and value flowing into the filter capacitor and the actual load through the closed-loop gain of the current loop, and the voltage of the filter capacitor and the actual load are the same, so as to obtain a transfer function describing the load voltage.

[0048] For example, see Figure 6 , Figure 6 A control block diagram corresponding to a target equivalent circuit provided in an embodiment of the present application. Figure 6 As shown, the load voltage from the output v c Multiply by the inverse of the virtual capacitive load sCv as the virtual current i Cv , the first output current i output by the equivalent impedance Lref The virtual current i of the virtual capacitive load needs to be subtracted Cv Afterwards, the second output current i output by the filter impedance is obtained through the current inner loop. L , the second output current i L Subtract the load current i flowing into the actual load o Equal to the flow into the filter capacitor C f The current flowing into C f The current and filter capacitor The product of is equal to the load voltage v across the actual load c .

[0049] The closed-loop gain is used to control the relationship between the second output current and the difference between the first output current and the virtual current. Exemplarily, when the current inner loop bandwidth is set much higher than the disturbance frequency, the closed-loop gain is used to control the second output current to be approximately equal to the difference between the first output current and the virtual current, and it can be considered that Gcur(s)≈1.

[0050] Among them, the inverse of the virtual capacitive load sC v It is a differential link of the load voltage. The virtual capacitive load is used to indicate the virtual capacitive load introduced into the first-order low-pass filter, that is, to prevent high-frequency noise from being amplified by the differential link. Figure 7 , Figure 7 This is a control block diagram corresponding to another target equivalent circuit provided in an embodiment of the present application. Figure 7 As shown, a first-order low-pass filter Multiplying with sCv to perform virtual capacitive load feedback, ω c is the cutoff frequency of the low-pass filter.

[0051] Furthermore, if Figure 7 The control block diagram shown in the figure, the resulting transfer function includes:

[0052]

[0053] In formula (1), v c (s) refers to the load voltage across the actual load; i o (s) refers to the load current flowing through the actual load; sC f refers to the impedance of the filter capacitor; PI(s) refers to the transfer function of the proportional-integral controller, K p Refers to the proportional gain, K i refers to the integral gain, and s refers to the Laplace operator; represents a first-order low-pass filter, ω c is the cut-off frequency of the low-pass filter; sC v Refers to the impedance of the virtual capacitive load; G cur (s) refers to the closed-loop gain of the current loop.

[0054] Furthermore, it can be known from the transfer function that when there is a disturbance in the load current flowing through the actual load, the load voltage across the actual load can be stabilized due to the addition of the virtual capacitive load.

[0055] S104: When a disturbance occurs in the load voltage across the actual load, the load current flowing into the actual load is changed based on the transfer function to reduce the influence of the disturbance on the load voltage.

[0056] The load current flowing into the actual load is changed in the following manner: the second output current is changed according to the transfer function to change the load current flowing into the actual load.

[0057] For example, as shown in formula (1), when there is a disturbance in the load current flowing through the actual load, the voltage across the filter capacitor and the virtual capacitive load will change. The current value required to reduce the interference can be calculated through the transfer function of the virtual capacitive load, and the corresponding current value is output through the current loop to change the second output current value output by the filter impedance. Since the load current flowing into the actual load is equivalent to the difference between the second output current output by the filter impedance and the capacitive current of the filter capacitor, the current value flowing into the actual load can be changed by changing the second output current output by the filter impedance to reduce the load voltage fluctuation and control the load voltage to be stable.

[0058] The method further includes: gradually increasing the capacitance value of the virtual capacitive load of the target equivalent circuit, and obtaining a Bode diagram corresponding to each virtual capacitive load, wherein the Bode diagram is used to describe the amplitude corresponding to the interference signal for the same frequency range; determining a target Bode diagram corresponding to which the amplitudes within the frequency range are all less than zero; and using the virtual capacitive load corresponding to the target Bode diagram as an enhanced capacitor to set the enhanced capacitor in the filtering circuit.

[0059] The Bode diagram corresponding to each virtual capacitive load reflects the amplitude obtained when adding different virtual capacitive loads and the interference signal in the same frequency range. In the Bode diagram, an amplitude less than zero means reduced interference, and an amplitude greater than zero means increased interference. Figure 8 and Fig. 9 , Figure 8 The Bode diagram corresponding to the embodiment of the present application without setting the virtual capacitive load is shown in FIG. Fig. 9 The Bode diagram corresponding to the setting of the virtual capacitive load provided in the embodiment of the present application is shown in FIG. Figure 8 and Fig. 9 As shown, the horizontal axis refers to the frequency range of the interference signal, the unit is Hz, and the vertical axis refers to the amplitude, the unit is decibel dB. Figure 8 It indicates that when the interference signal in the frequency range of 30 to 2000 Hz is applied, the amplitude is greater than zero, which means that the interference signal in this frequency range will be amplified and the anti-interference ability is poor. Fig. 9 It indicates that the amplitude of the interference signal in all frequency ranges is less than zero, which means that the interference signal in all frequency ranges is reduced and the anti-interference ability is strong.

[0060] In other words, as long as a capacitive load is set between the power converter and the load, it will definitely play a role in reducing the impact of the disturbance current. Among them, the virtual capacitive load can also be selected according to the actual situation of the load or the anti-disturbance requirement. If the anti-disturbance effect of the capacitive load is required to achieve the amplitude of the Bode diagram less than 1, it is not mandatory that the curve of the Bode diagram must achieve an amplitude less than zero. As long as the amplitude of the Bode diagram corresponding to the virtual capacitive load is less than 1, the anti-disturbance requirement can be met.

[0061] Furthermore, in practical applications, it is also possible to consider selecting an actual capacitive load to access the circuit. If the anti-interference needs to be achieved with an amplitude less than zero, the minimum capacitance value that can make the amplitude less than zero can be determined by simulating the Bode diagram. Exemplarily, the bandwidth of the voltage loop can be set constant through simulation software, such as MATLAB, and the various parameters of the target equivalent circuit can be set according to the actual power converter, filter circuit, and actual load, and the capacitance value of the virtual capacitive load added to the target equivalent circuit can be changed, and the current signal of the same frequency range can be set as the interference signal to simulate the Bode diagram corresponding to the target equivalent circuit when adding virtual capacitive loads of different capacitance values. Furthermore, the capacitance of the virtual capacitive load can be gradually increased. When the amplitude on the Bode diagram of a virtual capacitive load is determined to be less than zero, the virtual capacitive load is set in the actual circuit to determine the minimum capacitance that can achieve interference reduction.

[0062] For example, the virtual capacitive load can be set to 10 times the filter capacitor C f Capacitance value.

[0063] Based on the same application concept, the embodiments of the present application also provide an anti-disturbance device based on a virtual capacitive load corresponding to the anti-disturbance method based on a virtual capacitive load provided in the above embodiments. Since the principle of solving the problem by the device in the embodiments of the present application is similar to the anti-disturbance method based on a virtual capacitive load in the above embodiments of the present application, the implementation of the device can refer to the implementation of the method, and the repeated parts will not be repeated.

[0064] like Fig.10 As shown, Fig.10 A functional module diagram of an anti-disturbance device based on a virtual capacitive load provided in an embodiment of the present application. The anti-disturbance device 20 based on a virtual capacitive load includes: a first equivalent module 201, which constructs an initial equivalent circuit corresponding to a power converter, and the initial equivalent circuit is used to describe the circuit when the output end of the power converter supplies power to an actual load; a second equivalent module 202, which adds a virtual capacitive load to the initial equivalent circuit to obtain a target equivalent circuit, and the virtual capacitive load is connected in parallel to the two ends of the actual load in the equivalent circuit; a determination module 203, based on the target equivalent circuit, determines the transfer function corresponding to the actual load changed by the virtual capacitive load, and the transfer function is used to describe the ratio of the load voltage at both ends of the actual load to the load current flowing into the actual load; an adjustment module 204, when a disturbance is actually detected in the load voltage at both ends of the actual load, based on the transfer function, changes the load current flowing into the actual load to reduce the influence of the disturbance on the load voltage.

[0065] Based on the same application concept, see Fig.11As shown, it is a structural diagram of an electronic device provided in an embodiment of the present application, the electronic device 30 includes: a processor 301, a memory 302 and a bus 303, the memory 302 stores machine-readable instructions executable by the processor 301, when the electronic device 30 is running, the processor 301 communicates with the memory 302 through the bus 303, and the machine-readable instructions are executed by the processor 301 when running to perform the steps of the anti-disturbance method based on virtual capacitive load as described in any of the above embodiments.

[0066] Specifically, when the machine-readable instructions are executed by the processor 301, the following processing can be performed: constructing an initial equivalent circuit corresponding to the power converter, the initial equivalent circuit is used to describe the circuit when the output end of the power converter supplies power to the actual load; adding a virtual capacitive load to the initial equivalent circuit to obtain a target equivalent circuit, the virtual capacitive load is connected in parallel to the two ends of the actual load in the equivalent circuit; based on the target equivalent circuit, determining a transfer function corresponding to the actual load changed by the virtual capacitive load, the transfer function is used to describe the ratio of the load voltage at both ends of the actual load to the load current flowing into the actual load; when a disturbance is actually detected in the load voltage at both ends of the actual load, based on the transfer function, the load current flowing into the actual load is changed to reduce the impact of the disturbance on the load voltage.

[0067] Based on the same application concept, an embodiment of the present application further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the anti-disturbance method based on a virtual capacitive load provided in the above embodiment are executed.

[0068] Specifically, the storage medium can be a general storage medium, such as a mobile disk, a hard disk, etc. When the computer program on the storage medium is run, the above-mentioned anti-disturbance method based on the virtual capacitive load can be executed. The target equivalent circuit is obtained by constructing an initial equivalent circuit connected to the power converter, and adding a virtual capacitive load connected in parallel at both ends of the actual load to the initial equivalent circuit. The transfer function of the ratio of the voltage across the actual load to the load current flowing through the actual load is constructed through the target equivalent circuit. Then, when it is determined that there is a fluctuation in the voltage across the actual load, the load current flowing into the actual load is changed through the transfer function to stabilize the load voltage region, thereby solving the technical problem in the prior art that an additional actual capacitor needs to be set to reduce the fluctuation in the voltage across the load, thereby achieving the technical effect of improving the power supply stability.

[0069] Those skilled in the art can clearly understand that, for the convenience and simplicity of description, the specific working process of the system and device described above can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here. In the several embodiments provided in the present application, it should be understood that the disclosed system, device and method can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some communication interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0070] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0071] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0072] If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a non-volatile computer-readable storage medium that is executable by a processor. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, etc., various media that can store program codes.

[0073] The above are only specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. An anti-disturbance method based on virtual capacitive load, characterized in that: The method comprises: Constructing an initial equivalent circuit corresponding to the power converter, wherein the initial equivalent circuit is used to describe a circuit when the output end of the power converter supplies power to an actual load; Adding a virtual capacitive load to the initial equivalent circuit to obtain a target equivalent circuit, wherein the virtual capacitive load is connected in parallel to two ends of an actual load in the equivalent circuit; Based on the target equivalent circuit, determining a transfer function corresponding to changing the actual load through the virtual capacitive load, wherein the transfer function is used to describe a ratio of a load voltage across the actual load to a load current flowing into the actual load; When a disturbance occurs in the load voltage across the actual load, the load current flowing into the actual load is changed based on the transfer function to reduce the influence of the disturbance on the load voltage.

2. The method according to claim 1, characterized in that The initial equivalent circuit refers to a circuit equivalent to the output end of the power converter being connected to the actual load through a filter circuit, wherein the filter circuit includes a filter impedance and a filter capacitor. Wherein, the target equivalent circuit includes: A voltage source equivalent to the power converter; An equivalent impedance, one end of which is connected to one end of the voltage source, and the equivalent impedance is equivalent to the filter impedance on the filter circuit and the line impedance of the circuit where the power converter is located; a virtual capacitive load, one end of the virtual capacitive load being connected to the other end of the equivalent impedance, and the other end of the virtual capacitive load being connected to the other end of the voltage source; The actual load and the filter capacitor of the filter circuit are connected in parallel at both ends of the virtual capacitive load.

3. The method according to claim 2, characterized in that The first output current flowing out of the equivalent impedance in the target equivalent circuit is equal to the virtual current flowing through the virtual capacitive load and the second output current, and the second output current is used to indicate the current output by the filter impedance. The second output current is equal to the capacitive current flowing into the filter capacitor and the load current flowing through the actual load.

4. The method according to claim 3, characterized in that The transfer function corresponding to the actual load is determined in the following manner: Based on the target equivalent circuit, a control block diagram corresponding to the target equivalent circuit is constructed by introducing a proportional-integral controller, a current loop, a load voltage feedback and a virtual capacitive load feedback, and the transfer function is determined.

5. The method according to claim 4, characterized in that The transfer function corresponding to the actual load is determined in the following manner: The first output current is determined by comparing the expected voltage of the voltage source with the load voltage at both ends of the actual load through the proportional-integral controller; Determining the second output current through a closed-loop gain of a current loop according to the first output current and a virtual current flowing through the virtual capacitive load; The transfer function is constructed according to the transfer function of the proportional-integral controller, the closed-loop gain and the current flow trend of the second output current.

6. The method according to claim 5, characterized in that The closed-loop gain is used to control the relationship between the second output current and the difference between the first output current and the virtual current.

7. The method according to claim 5, characterized in that The virtual capacitive load is used to indicate a virtual capacitive load introduced into a first-order low-pass filter.

8. The method according to claim 3, characterized in that The load current flowing into the actual load is changed by: The second output current is changed according to the transfer function to change the load current flowing into the actual load.

9. The method according to claim 1, characterized in that: The method further comprises: Gradually increasing the capacitance value of the virtual capacitive load of the target equivalent circuit, and obtaining a Bode diagram corresponding to each virtual capacitive load, wherein the Bode diagram is used to describe the amplitude corresponding to the interference signal in the same frequency range; Determine a target Bode diagram corresponding to which the amplitudes within the frequency range are all less than zero; The virtual capacitive load corresponding to the target Bode diagram is used as an enhanced capacitor to set the enhanced capacitor in the filter circuit.

10. An anti-disturbance device based on a virtual capacitive load, characterized in that: The device comprises: A first equivalent module constructs an initial equivalent circuit corresponding to the power converter, wherein the initial equivalent circuit is used to describe a circuit when the output end of the power converter supplies power to an actual load; A second equivalent module, adding a virtual capacitive load to the initial equivalent circuit to obtain a target equivalent circuit, wherein the virtual capacitive load is connected in parallel to two ends of an actual load in the equivalent circuit; A determination module, based on the target equivalent circuit, determines a transfer function corresponding to changing the actual load through the virtual capacitive load, wherein the transfer function is used to describe a ratio of a load voltage across the actual load to a load current flowing into the actual load; The regulating module is configured to reduce the influence of the disturbance on the load voltage by changing the load current flowing into the actual load based on the transfer function when a disturbance occurs in the load voltage across the actual load.

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