Single-switch DC-DC converter self-excitation modeling system and control method thereof

Abstract

The invention discloses a single-switch DC-DC converter self-excitation modeling system and a control method thereof, which are applied to automatic identification, accurate modeling and automatic parameter adjustment of a single-switch DC-DC converter and can automatically identify any single-switch DC-DC converter and perform automatic modeling and control on the converter. On the basis of transient modeling, the modeling result has extremely high accuracy, the transient state of each state variable under the actual condition is well reflected, data analysis on the state variables is facilitated, ripples of the state variables can be reflected more accurately, adverse factors such as overvoltage and overcurrent which possibly occur are prevented, and the reliability of the system is improved. And the model selection of the device is facilitated. Meanwhile, on the basis of the modeling result and the Floquet theory, automatic adjustment of controller parameters can be achieved, so that the single-switch DC-DC converter can fall into a stable operation area of the system, and robustness and stability of the system are guaranteed.

Description

Technical Field

[0001] The invention relates to the field of converter modeling and control thereof, and in particular to a single-switch DC-DC converter self-excitation modeling system and a control method thereof. Background Art

[0002] With the rapid iteration of science and technology and the rapid development of the economy, the problems of energy shortage and environmental pollution are becoming increasingly acute. New energy systems have emerged and become the future trend of energy system development. As the main component of new energy systems, DC-DC converters are widely used in new energy power systems, electric vehicle systems, and automation fields. Whether the DC-DC converter can operate stably in the system is an important factor in ensuring the stability of the above systems. Therefore, it is necessary to model and analyze the converter in order to design a controller to ensure the steady state of the converter.

[0003] Since power electronic converters contain nonlinear elements such as diodes and switching devices, switching converters are highly nonlinear. This strong nonlinearity makes it difficult to accurately model switching converters. The most common modeling method is the state space averaging method. The modeling method based on the averaging method results in the state space averaging method only reflecting the average state of each state variable in the CCM mode, and cannot accurately describe the instantaneous state of each state variable of the converter. In addition, the modeling of DC-DC converters requires tedious mathematical derivation, and no automated, programmed, and highly integrated modeling integrated block is provided, which makes converter modeling difficult and slow.

[0004] In view of the above problems, the present invention discloses a single-switch DC-DC converter automatic modeling integrated block, which realizes automatic identification and modeling of DC-DC converters and ensures high accuracy of modeling results. In conjunction with the control parameter automatic adjustment module, the converter maintains steady-state operation, thereby ensuring the robustness and stability of the system and the convenience and universality of the modeling method. Summary of the invention

[0005] The present invention discloses a single-switch DC-DC converter self-excitation modeling system and a control method thereof, which are applied to the automatic identification, accurate modeling, and automatic parameter adjustment of a single-switch DC-DC converter, and can automatically identify any single-switch DC-DC converter, automatically model the converter, and implement control. On the basis of transient modeling, the modeling result has extremely high accuracy, and extremely well reflects the instantaneous state of each state variable under actual conditions, which is conducive to data analysis of the above-mentioned state variables, can more accurately reflect the ripple of the above-mentioned state variables, and prevent possible adverse factors such as overvoltage and overcurrent, which is conducive to the selection of devices. At the same time, based on the above-mentioned modeling results and Floquet theory, the automatic adjustment of the controller parameters can be realized, so that the single-switch DC-DC converter can fall into the stable operation area of ​​the system, ensuring the robustness and stability of the system.

[0006] A single-switch DC-DC converter self-excitation modeling system includes a modal identification module, a state variable identification module, a converter model automatic identification module, and a main control module:

[0007] The mode identification module is used to identify all modes of the single-switch DC-DC converter and send mode information to the state variable identification module;

[0008] The state variable identification module is used to identify all state variables in all modes of the single switch DC-DC converter and send all state variable information to the converter model automatic identification module;

[0009] The converter model automatic identification module includes a fitting factor sn(x) selection module and a function processing module. The fitting factor sn(x) selection module is used to smooth the modeling process so that the modeling has high precision and high accuracy. The function processing module is the main part of the automatic modeling system, which processes all state variable information to obtain the mathematical model of the single switch DC-DC converter, including the capacitor differential unified equation and the inductor differential unified equation, and sends the model information to the main control module.

[0010] The main control module is used to automatically adjust the controller internal parameters α1, α2, ..., α n , so that the single-switch DC-DC converter falls into a steady state. If the single-switch DC-DC converter enters a chaotic or bifurcation state, the internal parameters of the controller are automatically adjusted to quickly return to a steady state.

[0011] The modality recognition module recognizes the following contents:

[0012] Circuit diagram G1 in CCM mode with switch Q closed;

[0013] Circuit diagram G2 in CCM mode with switch Q disconnected;

[0014] Circuit diagram G3 in DCM mode with switch Q open.

[0015] The state variable identification module identifies the following contents:

[0016] The state variables of the circuit diagram G1 in the CCM mode with the switch Q closed identified by the above-mentioned mode identification module include:

[0017] F 1C (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0;

[0018] F 1L (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0;

[0019] The state variables of the circuit diagram G2 in the CCM mode with the switch Q disconnected identified by the above-mentioned mode identification module include:

[0020] F 2C (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0;

[0021] F 2L (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0;

[0022] The state variables of the circuit diagram G3 in the DCM mode with the switch Q disconnected identified by the above-mentioned mode identification module include:

[0023] F 3C (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0;

[0024] F 3L (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0.

[0025] The fitting factor sn(x) selection module includes the following options:

[0026] C1: Sigmoid curve, including: Logistic function and its generalized form;

[0027] C2: Special trigonometric functions and their generalized forms, including: tanh(x), arctan(x);

[0028] C3: Special cumulative distribution functions, including: Weibull distribution.

[0029] The function processing module is the main part for automatically modeling the single switch DC-DC converter, and the module processing steps are specifically as follows:

[0030] S1: F 1C (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0,F 2C (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0,F 3C (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0

[0031] Separate the variables into constant variables X at and 0 / 1 variable Y at , specifically:

[0032] F 1C (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0 is separated into constant variable X a1 and 0 / 1 variable Y a1 , denoted as F 11C , that is, F 11C =X a1 +Y a1 ;

[0033] F 2C (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0 is separated into constant variable X a2 and 0 / 1 variable Y a2 , denoted as F21C , that is, F 21C =X a2 +Y a2 ;

[0034] F 3C (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0 is separated into constant variable X a3 and 0 / 1 variable Y a3 , denoted as F 31C , that is, F 31C =X a3 +Y a3 ;

[0035] In fact, the constant variable X a1 = Constant variable X a2 = Constant variable X a3 , denoted as constant variable X A ;

[0036] S2: 0 / 1 variable Y at Transformed into a unified expression form S through the fitting factor sn(x) a1 , that is, the unified expression S a1 =(Y a1 +Y a2 +Y a3 )sn(x), where x = 100(cos(dπ)-cos(ωt-dπ)), where d is the converter duty cycle and ω is the Q switch angular frequency;

[0037] S3: Keep constant variable X A And with S a1 Combined, we get the capacitance differential unified equation G C =X A +S a1 ;

[0038] S4: F 1L (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0,F 2L (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0,F 3L (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0

[0039] Separate the variables into constant variables X bt and 0 / 1 variable Y bt , specifically:

[0040] F 1L (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0 is separated into constant variable X b1 and 0 / 1 variable Y b1 , denoted as F 11L , that is, F 11L =X b1 +Y b1 ;

[0041] F 2L (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0 is separated into constant variable X b2 and 0 / 1 variable Y b2 , denoted as F 21L , that is, F 21L =X b2 +Y b2 ;

[0042] F 3L (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0 is separated into constant variable X b3 and 0 / 1 variable Y b3 , denoted as F 31L , that is, F 31L =X b3 +Y b3 ;

[0043] In fact, the constant variable X b1 = Constant variable X b2 , denoted as constant variable X B ;

[0044] S5: 0 / 1 variable Y bt Transformed into a unified expression form S through the fitting factor sn(x) b1 , that is, S b1 =(Y b1 +Y b2 +Y b3)sn(x), where x = 100(cos(dπ)-cos(ωt-dπ)), where d is the converter duty cycle and ω is the switch Q angular frequency;

[0045] S6: Compensation for negative factor S b2 :F 21L It is transformed into a unified expression form S by acting with 1 / 2 times the fitting factor sn(x) b2 , that is, the unified expression S b2 =F 2L sn(x), when x=i L , where i L is the inductor current;

[0046] S7: Keep constant variable X B And with S b1 , S b2 Combined, we get the unified differential equation of inductance G L =X B +S b1 -S b .

[0047] The main control module includes a controller parameter automatic adjustment module, a controller, and a driver:

[0048] The controller parameter automatic adjustment module selects the internal parameters of the controller based on the mathematical model of the single-switch DC-DC converter, so that the single-switch DC-DC converter operates in a steady state, and inputs the parameters to the controller;

[0049] The controller is used to send a PWM control signal to drive the driver to control the on and off of the switch Q.

[0050] The main control module and the module processing specific steps are:

[0051] Spet1: Identify controller model, capacitor differential unified equation, inductor differential unified equation;

[0052] Spet2: performing partial differential derivation on the controller model, the capacitor differential unified equation, and the inductor differential unified equation to obtain a Jacobi matrix J;

[0053] Spet3: Calculate the single value matrix M of the Jacobian matrix J. The single value matrix M is calculated by the formula

[0054]

[0055] We get: k N is the switching period of switch Q k Equal time periods, J k △ kJacobian matrix in time period, k=1, 2, ..., N k ;

[0056] Spe4: The module automatically changes the control parameters α1, α2, ...., α n , the stable and unstable regions of the system are obtained through Floquet theory. If the control parameters α1, α2, ...., α n So that the system output falls into the stable region, the control parameters α1, α2, ..., α n If feasible, input the controller, otherwise, give new control parameters α1, α2, ..., α n Repeat the above steps. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. For ordinary technicians in this field, other drawings can also be obtained based on these drawings without creative work.

[0058] Figure 1 A flowchart for automatic modeling and control of a single-switch DC-DC converter;

[0059] Figure 2 The circuit diagram of the improved multi-unit switched inductor converter is as follows;

[0060] Figure 3 A circuit diagram for the mode identification module to identify the CCM mode of the improved multi-unit switched inductor converter with the switch Q closed;

[0061] Figure 4 A circuit diagram for a mode identification module to identify a CCM mode of an improved multi-unit switched inductor converter with switch Q disconnected;

[0062] Figure 5 A circuit diagram for a mode identification module to identify a DCM mode of an improved multi-unit switched inductor converter with switch Q disconnected;

[0063] Figure 6 It is a schematic diagram of a current-mode single-cycle adaptive controller;

[0064] Figure 7 It is a schematic diagram of the value range of control parameters ε and q;

[0065] Where: n is the number of inductors, C is the capacitance, R is the load resistance, L1=L2=....=L n= L is the inductance value, i L1 =i L2 ...=i Ln =i L is the transient value of the inductor current, v C is the transient value of the capacitor voltage and also the transient value of the output voltage, V o is the average output voltage, V in is the input voltage, ε and q are the controller parameters. DETAILED DESCRIPTION

[0066] In order to make the purpose, technical scheme and features in the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0067] The embodiment of the present application provides a single-switch DC-DC converter self-excitation modeling system and a control method thereof, which are used to perform transient modeling on the single-switch DC-DC converter, which is conducive to analyzing the transient of each state variable of the converter and can more accurately reflect the ripple of the converter.

[0068] A typical embodiment of the present invention takes the circuit of an improved multi-unit switching inductor converter as an example. Figure 2 This is the circuit diagram of the improved multi-unit switch inductor converter. Taking the current-type single-cycle adaptive controller as an example, the internal parameters of the controller are ε, q, Figure 6 This is the schematic diagram of the current-mode single-cycle adaptive controller. The function is the fitting factor s1(x), when the factor is negative, x=i L , when the variable is 1 / 0, x=100(cos(dπ)-cos(ωt-dπ)).

[0069] Please refer to Figure 1 , the modality recognition module recognizes the following contents:

[0070] Please refer to Figure 3 , Figure 3 A circuit diagram for the mode identification module to identify the CCM mode of the improved multi-unit switched inductor converter with the switch Q closed;

[0071] Please refer to Figure 4 , Figure 4 A circuit diagram for a mode identification module to identify a CCM mode of an improved multi-unit switched inductor converter with switch Q disconnected;

[0072] Please refer to Figure 5 , Figure 5 A circuit diagram for a mode identification module to identify a DCM mode of an improved multi-unit switched inductor converter with switch Q disconnected;

[0073] Please refer to Figure 1 The state variable identification module identifies the following contents:

[0074] The state variables of the circuit diagram G1 in the CCM mode with the switch Q closed identified by the above-mentioned mode identification module include:

[0075]

[0076]

[0077] The state variables of the circuit diagram G2 in the CCM mode with the switch Q disconnected identified by the above-mentioned mode identification module include:

[0078]

[0079]

[0080] The state variables of the circuit diagram G3 in the DCM mode with the switch Q disconnected identified by the above-mentioned mode identification module include:

[0081]

[0082]

[0083] The fitting factor sn(x) selection module selects Sigmoid curve, and the specific expression is:

[0084]

[0085] When compensating for negative factors x = i L , when the variable is 1 / 0, x=100(cos(dπ)-cos(ωt-dπ)).

[0086] Please refer to Figure 1 , the processing steps of the function processing module are specifically as follows:

[0087] S1: F 1C (i L ,v C )=0,F 2C (i L ,v C )=0,F 3C (i L ,v C )=0 to separate the variables into constant variables X atand 0 / 1 variable Y at :

[0088] F 1C (i L ,v C )=0 is separated into constant variable X a1 and 0 / 1 variable Y a1 , that is, F 11C =X a1 +Y a1 , denoted as F 11C :

[0089]

[0090] Available, Y a1 =0;

[0091] F 2C (i L ,v C )=0 is separated into constant variable X a2 and 0 / 1 variable Y a2 , that is, F 21C =X a2 +Y a2 , denoted as F 21C :

[0092]

[0093] Available, Y a2 =i L ;

[0094] F 3C (i L ,v C )=0 is separated into constant variable X a3 and 0 / 1 variable Y a3 , that is, F 31C =X a3 +Y a3 , denoted as F 31C :

[0095]

[0096] Available, Y a3 =0;

[0097] In fact, Let it be the constant variable X A .

[0098] S2: 0 / 1 variable Y at Transformed into a unified expression form S through the fitting factor s1(x)a1 , that is, S a1 =(Y a1 +Y a2 +Y a3 )s1(x), where x = 100(cos(dπ)-cos(ωt-dπ)), where d is the duty cycle of the converter, ω is the Q switch angular frequency, S a1 As shown below.

[0099] S a1 =i L S[100(cos(dπ)-cos(wt-dπ))]

[0100] S3: Derive the unified differential equation of capacitance G C , specifically, keep the constant variable X A And with S a1 Combined, that is, the capacitance differential unified equation G C =S a1 +X A As shown below.

[0101]

[0102] S4: F 1L (i L ,v C )=0,F 2L (i L ,v C )=0,F 3L (i L ,v C )=0 to separate the variables into constant variables X bx and 0 / 1 variable Y bx :

[0103] F 1L (i L ,v C )=0 is separated into constant variable X b1 and 0 / 1 variable Y b1 , that is, F 11L =X b1 +Y b1 , denoted as F 11L :

[0104]

[0105] Available, X b1 =V in , Y b1 =0;

[0106] F 2L (i L ,vC )=0 is separated into constant variable X b2 and 0 / 1 variable Y b2 , that is, F 21L =X b2 +Y b2 , denoted as F 21L :

[0107]

[0108] Available, X b2 =V in ,

[0109] F 3L (i L ,v C )=0 is separated into constant variable X b3 and 0 / 1 variable Y b3 , that is, F 31L =X b3 +Y b3 , denoted as F 31L :

[0110]

[0111] Available, X b3 =0, Y b3 =0;

[0112] In fact, X b1 =X b2 =V in , denoted as constant variable X B .

[0113] S5: 0 / 1 variable Y bt Transformed into a unified expression form S through the fitting factor s1(x) b1 , that is, S b1 =(Y b1 +Y b2 +Y b3 )sn(x), where x = 100(cos(dπ)-cos(ωt-dπ)), where d is the duty cycle of the converter, ω is the switch Q angular frequency, S b1 As shown below.

[0114]

[0115] S6: Compensation for negative factor S b2 , specifically, F 2L It is transformed into a unified expression form S by acting with 1 / 2 times the fitting factor s1(x) b2 , at this time x=i L , where iL is the inductor current, that is, S b2 =F 2L s1(x), S b2 As shown below.

[0116]

[0117] S7: Obtain the unified differential equation of inductance G L , specifically, keep the constant variable X B And with S b1 , S b2 Combined, that is, the unified differential equation of inductance G L =X B +S b1 -S b2 , G L As shown below.

[0118]

[0119] The controller parameter automatic adjustment module is used to automatically adjust the internal parameters of the controller so that the system can enter a stable operation state and can automatically return to a stable state from a chaotic state. The specific steps of the module processing are:

[0120] Spet1: Identify the current-mode single-cycle adaptive controller model, capacitor differential unified equation, and inductor differential unified equation, as shown below.

[0121]

[0122]

[0123]

[0124] Spet2: The current-type single-cycle adaptive controller model, the capacitor differential unified equation, and the inductor differential unified equation are partially differentiated to obtain the Jacobian matrix J, which is shown below.

[0125]

[0126] Spet3: Calculate the single value matrix M of the Jacobian matrix J. The single value matrix M is calculated by the formula

[0127]

[0128] We get: k N is the switching period of switch Q k Equal time periods, J k △ k Jacobian matrix in time period, k=1, 2, ..., Nk .

[0129] Spet4: The module automatically changes the control parameters ε and q. The stable area and unstable area of ​​the system can be obtained through the Floquet theory. Specifically, if the control parameters ε and q make the system output fall into the stable area, then the control parameters ε and q are feasible and are input into the controller. Otherwise, new control parameters ε1 and q1 are given to repeat the above steps.

[0130] Please refer to Figure 7 , and finally the value range of control parameters ε and q can be obtained so that the system is in a steady state.

[0131] In summary, the present invention discloses a single-switch DC-DC converter self-excitation modeling system and a control method thereof. The method automatically performs identification and modeling on the single-switch DC-DC converter, facilitates the modeling process, and improves the modeling rate. The modeling result reflects the transient state of each state variable in the single-switch DC-DC converter very well, which is conducive to data analysis of the state variables, thereby preventing the influence of adverse factors such as overvoltage and overcurrent, and providing a more accurate controller parameter range.

[0132] The above-mentioned embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. The description of the embodiments disclosed in the present invention enables professional and technical personnel in the field to use or implement the present invention. They can still modify the technical solutions recorded in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these replacements or modifications do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A single-switch DC-DC converter self-excitation modeling system, characterized in that: Including modal identification module, state variable identification module, converter model automatic identification module, main control module: The mode identification module is used to identify all modes of the single-switch DC-DC converter and send mode information to the state variable identification module; The state variable identification module is used to identify all state variables in all modes of the single switch DC-DC converter and send all state variable information to the converter model automatic identification module; The converter model automatic identification module includes a fitting factor sn(x) selection module and a function processing module. The fitting factor sn(x) selection module is used to smooth the modeling process so that the modeling has high precision and high accuracy; the function processing module is used to process all state variable information to obtain the mathematical model of the single switch DC-DC converter, including the capacitor differential unified equation and the inductor differential unified equation, and send the model information to the main control module; The main control module is used to automatically adjust the controller internal parameters α1, α2, ..., α n , so that the single-switch DC-DC converter falls into a steady state. If the single-switch DC-DC converter enters a chaotic or bifurcation state, the internal parameters of the controller are automatically adjusted to quickly return to a steady state.

2. A single switch DC-DC converter self-excitation modeling system according to claim 1, characterized in that: The modal recognition module mentioned in the automatic modeling includes: Circuit diagram G1 in CCM mode with switch Q closed; Circuit diagram G2 in CCM mode with switch Q disconnected; Circuit diagram G3 in DCM mode with switch Q open.

3. A single switch DC-DC converter self-excitation modeling system according to claim 1, characterized in that: The state variable identification module identifies the following contents: The state variables of the circuit diagram G1 in the CCM mode with the switch Q closed identified by the above-mentioned mode identification module include: F 1C (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0; F 1L (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0; The state variables of the circuit diagram G2 in the CCM mode with the switch Q disconnected identified by the above-mentioned mode identification module include: F 2C (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0; F 2L (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0; The state variables of the circuit diagram G3 in the DCM mode with the switch Q disconnected identified by the above-mentioned mode identification module include: F 3C (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0; F 3L (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0。 4. The single-switch DC-DC converter self-excitation modeling system according to claim 1, characterized in that: The fitting factor sn(x) selection module includes the following options: C1: Sigmoid curve, including: Logistic function and its generalized form; C2: Special trigonometric functions and their generalized forms, including: tanh(x), arctan(x); C3: Special cumulative distribution functions, including: Weibull distribution.

5. The single-switch DC-DC converter self-excitation modeling system of claim 1, wherein the function processing module mentioned in the automatic modeling is characterized by: The module processing steps are as follows: S1: Set F 1C (i L1 ,...,i Ln ,v C1 ,...,v Cn ) = 0, F 2C (i L1 ,...,i Ln ,v C1 ,...,v Cn ) = 0, F 3C (i L1 ,...,i Ln ,v C1 ,...,v Cn ) = 0 Separate the variables into constant variables X at and 0 / 1 variable Y at , specifically: F 1C (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0 is separated into constant variable X a1 and 0 / 1 variable Y a1 , denoted as F 11C , that is, F 11C =X a1 +Y a1 ; F 2C (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0 is separated into constant variable X a2 and 0 / 1 variable Y a2 , denoted as F 21C , that is, F 21C =X a2 +Y a2 ; F 3C (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0 is separated into constant variable X a3 and 0 / 1 variable Y a3 , denoted as F 31C , that is, F 31C =X a3 +Y a3 ; In fact, the constant variable X a1 = Constant variable X a2 = Constant variable X a3 , denoted as constant variable X A ; S2: 0 / 1 variable Y at Transformed into a unified expression form S through the fitting factor sn(x) a1 , that is, the unified expression S a1 =(Y a1 +Y a2 +Y a3 )sn(x), where x = 100(cos(dπ)-cos(ωt-dπ)), where d is the converter duty cycle and ω is the Q switch angular frequency; S3: Keep constant variable X A And with S a1 Combined, we get the capacitance differential unified equation G C =X A +S a1 ; S4: Set F 1L (i L1 ,...,i Ln ,v C1 ,...,v Cn ) = 0, F 2L (i L1 ,...,i Ln ,v C1 ,...,v Cn ) = 0, F 3L (i L1 ,...,i Ln ,v C1 ,...,v Cn ) = 0 Separate the variables into constant variables X bt and 0 / 1 variable Y bt , specifically: F 1L (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0 is separated into constant variable X b1 and 0 / 1 variable Y b1 , denoted as F 11L , that is, F 11L =X b1 +Y b1 ; F 2L (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0 is separated into constant variable X b2 and 0 / 1 variable Y b2 , denoted as F 21L , that is, F 21L =X b2 +Y b2 ; F 3L (i L1 ,...,i Ln ,v C1 ,...,v Cn )=0 is separated into constant variable X b3 and 0 / 1 variable Y b3 , denoted as F 31L , that is, F 31L =X b3 +Y b3 ; In fact, the constant variable X b1 = Constant variable X b2 , denoted as constant variable X B ; S5: 0 / 1 variable Y bt Transformed into a unified expression form S through the fitting factor sn(x) b1 , that is, S b1 =(Y b1 +Y b2 +Y b3 )sn(x), where x = 100(cos(dπ)-cos(ωt-dπ)), where d is the converter duty cycle and ω is the switch Q angular frequency; S6: Compensation for negative factor S b2 :F 21L It is transformed into a unified expression form S by acting with 1 / 2 times the fitting factor sn(x) b2 , that is, the unified expression S b2 =F 2L sn(x), when x=i L , where i L is the inductor current; S7: Keep constant variable X B And with S b1 , S b2 Combined, we get the unified differential equation of inductance G L =X B +S b1 -S b .

6. The single switch DC-DC converter self-excitation modeling system according to claim 1, characterized in that: The main control module includes a controller parameter automatic adjustment module, a controller, and a driver: The controller parameter automatic adjustment module selects the internal parameters of the controller based on the mathematical model of the single-switch DC-DC converter, so that the single-switch DC-DC converter operates in a steady state, and inputs the parameters to the controller; The controller is used to send a PWM control signal to drive the driver to control the on and off of the switch Q.

7. A single switch DC-DC converter self-excitation modeling system control method, characterized in that: The specific steps of the main control module processing described in claim 6 are: Spet1: Identify controller model, capacitor differential unified equation, inductor differential unified equation; Spet2: performing partial differential derivation on the controller model, the capacitor differential unified equation, and the inductor differential unified equation to obtain a Jacobi matrix J; Spet3: Calculate the single value matrix M of the Jacobian matrix J. The single value matrix M is calculated by the formula We get: k N is the switching period of switch Q k Equal time periods, J k △ k Jacobian matrix in time period, k=1, 2, ..., N k ; Spe4: The module automatically changes the control parameters α1, α2, ...., α n , the stable and unstable regions of the system are obtained through Floquet theory. If the control parameters α1, α2, ...., α n So that the system output falls into the stable region, the control parameters α1, α2, ..., α n If feasible, input the controller, otherwise, give new control parameters α1, α2, ..., α n Repeat the above steps.

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