Method and device for stabilizing voltage output and energy router system

Abstract

The invention discloses a method and device for stabilizing voltage output and an energy router system. The method comprises the steps that an energy router system is determined, the energy router system comprises a voltage control circuit, a first state observer, a second state observer and a complementary sliding mode controller, the voltage control circuit is connected with a load, and the voltage control circuit is connected with a direct current bus; determining a first disturbance estimation value corresponding to the first state observer and a second disturbance estimation value corresponding to the second state observer; inputting the first disturbance estimation value and the second disturbance estimation value into a complementary sliding mode controller to obtain a sliding mode control law; adjusting the reference pulse broadband modulation signal according to a sliding mode control law, and determining a target pulse broadband modulation signal; and controlling a switching tube of the voltage control circuit according to the target pulse broadband modulation signal so as to supply voltage to a load. According to the invention, the technical problem that the voltage supply is unstable when the energy router system supplies the voltage to the load in the prior art is solved.

Description

Technical Field

[0001] The present invention relates to the field of data processing, and in particular to a method and device for stabilizing voltage output and an energy router system. Background Art

[0002] In the energy router system, the DC load port usually uses a Buck converter to achieve voltage level conversion to power the DC load. Because it is connected to the DC bus, the input voltage is the DC bus voltage, and the DC bus voltage is fluctuating. At the same time, the load resistance will change due to external uncertain factors. The above factors will have an adverse effect on the output voltage of the Buck converter, resulting in output voltage instability. Summary of the invention

[0003] The embodiments of the present invention provide a method, device and energy router system for stabilizing voltage output, so as to at least solve the technical problem of unstable voltage supply when supplying voltage to a load in an energy router system in the related art.

[0004] According to one aspect of an embodiment of the present invention, a method for stabilizing voltage output is provided, comprising: determining an energy router system, wherein the energy router system comprises a voltage control circuit, a first state observer, a second state observer, and a complementary sliding mode controller, wherein the voltage control circuit is connected to a load, the voltage control circuit is connected to a DC bus, the voltage control circuit is electrically connected to the first state observer and the second state observer, respectively, the voltage control circuit is electrically connected to the complementary sliding mode controller, and the complementary sliding mode controller is electrically connected to the first state observer and the second state observer, respectively; determining a first disturbance estimation value corresponding to the first state observer and a second disturbance estimation value corresponding to the second state observer; inputting the first disturbance estimation value and the second disturbance estimation value into the complementary sliding mode controller to obtain a sliding mode control law; adjusting a reference pulse broadband modulation signal according to the sliding mode control law to determine a target pulse broadband modulation signal; and controlling a switch tube of the voltage control circuit according to the target pulse broadband modulation signal to supply voltage to the load.

[0005] Optionally, before determining the energy router system, the method further includes: determining, based on the voltage control circuit, a resistance change term corresponding to the resistance change caused by the load, and determining a voltage fluctuation term corresponding to the voltage fluctuation caused by the DC bus; determining the first state observer based on the resistance change term, determining the second state observer based on the voltage fluctuation term, and determining the complementary sliding mode controller based on the resistance change term and the voltage fluctuation term.

[0006] Optionally, the first disturbance estimate value and the second disturbance estimate value are input into the complementary sliding mode controller to obtain a sliding mode control law, including: when the complementary sliding mode controller includes an integral sliding surface and a complementary sliding surface, determining a target integral sliding surface and a target complementary sliding surface based on the first disturbance estimate value and the second disturbance estimate value; determining the sliding mode control law based on the target integral sliding surface and the target complementary sliding surface.

[0007] Optionally, before determining the energy router system, it also includes: determining a first stability analysis function corresponding to the resistance change term, a second stability analysis function corresponding to the voltage fluctuation term, and a third stability analysis function corresponding to the complementary sliding mode controller; verifying a first convergence result of whether the resistance change term converges when time tends to 0, and a first positive and negative result of a first verification term based on the first stability analysis function, and verifying a second convergence result of whether the voltage fluctuation term converges when time tends to 0, and a second positive and negative result of the second verification term based on the second stability analysis function, and verifying a third positive and negative result of a third verification term of the complementary sliding mode controller based on the third stability analysis function; determining an elimination result based on the first convergence result, the first positive and negative result, the second convergence result, the second positive and negative result, and the third positive and negative result, wherein the elimination result is a result indicating whether the settings in the energy router system can eliminate the disturbance.

[0008] Optionally, before determining the energy router system, the method further includes: when the elimination result is that the disturbance cannot be eliminated, adjusting the load and the DC bus connected in the energy router system until an elimination result that can eliminate the disturbance is obtained.

[0009] Optionally, before determining the energy router system, it also includes: determining an updated disturbance term causing disturbance in the energy router system; determining a third state observer corresponding to the updated disturbance term; connecting the third state observer to the energy router system to obtain an updated energy router system.

[0010] According to one aspect of an embodiment of the present invention, a device for stabilizing voltage output is provided, comprising: a first determining module, used to determine an energy router system, wherein the energy router system comprises a voltage control circuit, a first state observer, a second state observer, and a complementary sliding mode controller, wherein the voltage control circuit is connected to a load, the voltage control circuit is connected to a DC bus, the voltage control circuit is electrically connected to the first state observer and the second state observer respectively, the voltage control circuit is electrically connected to the complementary sliding mode controller, and the complementary sliding mode controller is electrically connected to the first state observer and the second state observer respectively; a second determining module, used to determine a first disturbance estimation value corresponding to the first state observer, and a second disturbance estimation value corresponding to the second state observer; a third determining module, used to input the first disturbance estimation value and the second disturbance estimation value into the complementary sliding mode controller to obtain a sliding mode control law; a regulating module, used to regulate a reference pulse broadband modulation signal according to the sliding mode control law to determine a target pulse broadband modulation signal; and a voltage supply module, used to control a switch tube of the voltage control circuit according to the target pulse broadband modulation signal to supply voltage to the load.

[0011] According to one aspect of an embodiment of the present invention, an energy router system is provided, including: a voltage control circuit, a first state observer, a second state observer, and a complementary sliding mode controller, wherein the voltage control circuit is connected to a load, the voltage control circuit is connected to a DC bus, the voltage control circuit is electrically connected to the first state observer and the second state observer, respectively, the voltage control circuit is electrically connected to the complementary sliding mode controller, and the complementary sliding mode controller is electrically connected to the first state observer and the second state observer, respectively.

[0012] According to one aspect of an embodiment of the present invention, there is provided an electronic device, comprising: a processor; and a memory for storing instructions executable by the processor; wherein the processor is configured to execute the instructions to implement any of the above-described methods for stabilizing voltage output.

[0013] According to one aspect of an embodiment of the present invention, a computer-readable storage medium is provided. When instructions in the computer-readable storage medium are executed by a processor of an electronic device, the electronic device can execute any one of the above-mentioned methods for stabilizing voltage output.

[0014] In an embodiment of the present invention, an energy router system is determined, wherein the energy router system includes a voltage control circuit, a first state observer, a second state observer, a complementary sliding mode controller, the voltage control circuit is connected to the load, the voltage control circuit is connected to the DC bus, the voltage control circuit is electrically connected to the first state observer and the second state observer respectively, the voltage control circuit is electrically connected to the complementary sliding mode controller, and the complementary sliding mode controller is electrically connected to the first state observer and the second state observer respectively. A first disturbance estimate corresponding to the first state observer and a second disturbance estimate corresponding to the second state observer are determined. The first disturbance estimate and the second disturbance estimate are input to the complementary sliding mode controller to obtain a sliding mode control law. According to the sliding mode control law, a reference pulse broadband modulation signal is adjusted to determine a target pulse broadband modulation signal. According to the target pulse broadband modulation signal, the switch tube of the voltage control circuit is controlled to supply voltage to the load. Since the first state observer and the second state observer are set up, the disturbance caused by different factors is determined, and the complementary sliding mode controller is set up to eliminate the disturbance, and a stable target pulse bandwidth modulation signal is obtained, so that the switch tube of the voltage control circuit can be controlled according to the stable target pulse bandwidth modulation signal to stably supply pressure to the load. Thus, the technical problem of unstable pressure supply when supplying pressure to the load in the energy router system in the related art is solved. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0016] Figure 1 is a flow chart of a method for stabilizing voltage output according to an embodiment of the present invention;

[0017] Figure 2 is a schematic diagram of an energy router system provided according to an optional embodiment of the present invention;

[0018] Figure 3 It is a schematic diagram of the topological structure of a conventional BUCK converter in the prior art;

[0019] Figure 4 is a control block diagram including an improved BUCK converter provided by an optional embodiment of the present invention;

[0020] Figure 5 4 is a structural block diagram of a device for stabilizing voltage output according to an embodiment of the present invention. DETAILED DESCRIPTION

[0021] In order to enable those skilled in the art to better understand the scheme of the present invention, 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 should fall within the scope of protection of the present invention.

[0022] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0023] First, some nouns or terms that appear in the description of the embodiments of the present application are subject to the following explanations:

[0024] BUCK converter: also known as step-down converter, series switching power supply or three-terminal switching step-down regulator, is a power electronic device mainly used to convert DC voltage into a lower DC voltage.

[0025] ESO state observer: Extended State Observer (ESO), is an advanced state observation technology widely used in Active Disturbance Rejection Control (ADRC).

[0026] Complementary sliding mode controller: It is an advanced nonlinear control strategy that originates from and improves the traditional sliding mode control theory. Complementary sliding mode control aims to overcome the problems of chattering and excessive switching frequency in practical applications of traditional sliding mode control. Its basic idea is to design a special control law so that the system can quickly enter and maintain the sliding state on a specific sliding surface, thereby achieving accurate tracking or steady-state control of the system.

[0027] Lyapunov function: It is a mathematical tool widely used in control system theory and system dynamics, mainly used to analyze the stability and instability of nonlinear dynamic systems.

[0028] Example 1

[0029] According to an embodiment of the present invention, an embodiment of a method for stabilizing voltage output is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0030] Figure 1 is a flow chart of a method for stabilizing voltage output according to an embodiment of the present invention. Figure 1 As shown, the method comprises the following steps:

[0031] Step S102, determining an energy router system, wherein the energy router system includes a voltage control circuit, a first state observer, a second state observer, and a complementary sliding mode controller, the voltage control circuit is connected to the load, the voltage control circuit is connected to the DC bus, the voltage control circuit is electrically connected to the first state observer and the second state observer respectively, the voltage control circuit is electrically connected to the complementary sliding mode controller, and the complementary sliding mode controller is electrically connected to the first state observer and the second state observer respectively;

[0032] In step S102 provided in the present application, an energy router system is involved. The energy router system is an electric energy conversion and energy management device based on power electronics technology and information technology, which can realize the reasonable allocation and optimization control of electric power resources. Since it includes a voltage control circuit, it can realize voltage control.

[0033] Among them, the voltage control circuit can be a BUCK circuit, which is a DC-DC converter based on the principle of inductive energy storage, also known as a step-down circuit. Its main function is to convert the DC voltage provided by the input power supply into an adjustable low voltage output by controlling the on and off state of the switch tube by switching the input PWM wave with a variable input duty cycle to meet the power supply requirements of different circuits. It can be seen that by setting this circuit, a more stable voltage output can be achieved.

[0034] The first state observer and the second state observer can both be ESO state observers. ESO (Extended State Observer) is a core component in the framework of Active Disturbance Rejection Control (ADRC), which can estimate the uncertainty and external disturbances in the system in real time. By accurately estimating these disturbances, it lays the foundation for the subsequent elimination of these disturbances.

[0035] Among them, the complementary sliding mode controller designs a special control law to enable the system to quickly enter and maintain the sliding state on a specific sliding surface, thereby achieving precise tracking or steady-state control of the system.

[0036] It should be noted that the above-mentioned first state observer, second state observer, and complementary sliding mode controller are all set according to the voltage control circuit and actual applications and scenarios, so that the first state observer and the second state observer can estimate the internal state of the energy router system.

[0037] Step S104, determining a first disturbance estimation value corresponding to the first state observer and a second disturbance estimation value corresponding to the second state observer;

[0038] In step S104 provided in the present application, in the design of the state observer, the disturbance is usually regarded as an additional state variable for estimation. By comparing the difference between the actual output and the output estimated by the state observer (i.e., the observation error), the estimated value of the disturbance can be calculated, and then the first disturbance estimate and the second disturbance estimate can be calculated to eliminate the interference.

[0039] It should be noted that the system state and disturbance may change over time. Therefore, the state observer can continuously iteratively update its state estimate and disturbance estimate to better perform subsequent calibration.

[0040] Step S106, inputting the first disturbance estimation value and the second disturbance estimation value into a complementary sliding mode controller to obtain a sliding mode control law;

[0041] In step S106 provided in the present application, a state observer (such as ESO) is used to estimate the first disturbance estimate and the second disturbance estimate in the system in real time according to the input and output information of the system. This disturbance estimate represents the unpredictable or uncontrollable factors in the system. The first disturbance estimate and the second disturbance estimate are input into the complementary sliding mode controller to obtain the sliding mode control law, that is, the disturbance estimate can be used as one of the control laws, and the influence of the disturbance can be compensated by adjusting the parameters of the control law, and then the calculated sliding mode control law is applied to the system to achieve accurate tracking or steady-state control of the system.

[0042] Step S108, adjusting the reference pulse wideband modulation signal according to the sliding mode control law to determine the target pulse wideband modulation signal;

[0043] In step S108 provided in the present application, that is, the sliding mode control law can adjust the reference pulse broadband modulation signal so that the system state can quickly approach the sliding mode surface and keep sliding on the sliding mode surface, thereby realizing signal regulation and reducing interference in the signal, thereby determining to obtain the target pulse broadband modulation signal.

[0044] Step S110 , controlling the switch tube of the voltage control circuit according to the target pulse width modulation signal to supply voltage to the load.

[0045] In step S110 provided in the present application, the target pulse broadband modulation signal indirectly controls the voltage or power and other parameters of the output signal by changing the width of the pulse. This technology makes the switch tube have only two states (on or off), so that there is almost no energy loss during operation, which improves the energy utilization of the system. Since the switch tube can quickly switch between the on and off states, the voltage control circuit based on PWM control also has the characteristics of fast response. This enables the system to quickly adapt to changes in the load and provide a stable voltage supply for the load. The target pulse broadband modulation signal allows the width of the pulse to be precisely controlled, thereby achieving precise regulation of the output voltage. This high-precision control enables the system to meet the precise voltage requirements of different loads. To provide a more stable pressure supply to the load.

[0046] Through the above steps S102-S110, an energy router system is determined, wherein the energy router system includes a voltage control circuit, a first state observer, a second state observer, a complementary sliding mode controller, the voltage control circuit is connected to the load, the voltage control circuit is connected to the DC bus, the voltage control circuit is electrically connected to the first state observer and the second state observer respectively, the voltage control circuit is electrically connected to the complementary sliding mode controller, and the complementary sliding mode controller is electrically connected to the first state observer and the second state observer respectively. A first disturbance estimate corresponding to the first state observer and a second disturbance estimate corresponding to the second state observer are determined. The first disturbance estimate and the second disturbance estimate are input into the complementary sliding mode controller to obtain a sliding mode control law. According to the sliding mode control law, a reference pulse broadband modulation signal is adjusted to determine a target pulse broadband modulation signal. According to the target pulse broadband modulation signal, the switch tube of the voltage control circuit is controlled to supply voltage to the load. Since the first state observer and the second state observer are set up, the disturbance caused by different factors is determined, and the complementary sliding mode controller is set up to eliminate the disturbance, and a stable target pulse bandwidth modulation signal is obtained, so that the switch tube of the voltage control circuit can be controlled according to the stable target pulse bandwidth modulation signal to stably supply pressure to the load. Thus, the technical problem of unstable pressure supply when supplying pressure to the load in the energy router system in the related art is solved.

[0047] As an optional embodiment, before determining the energy router system, it also includes: determining, based on the voltage control circuit, a resistance change item corresponding to the resistance change caused by the load, and determining a voltage fluctuation item corresponding to the voltage fluctuation caused by the DC bus; determining a first state observer based on the resistance change item, and determining a second state observer based on the voltage fluctuation item, and determining a complementary sliding mode controller based on the resistance change item and the voltage fluctuation item.

[0048] In this embodiment, in the energy router system, the DC load port usually adopts a Buck converter to realize the conversion of voltage level to supply power to the DC load. Because it is connected to the DC bus, the input voltage is the DC bus voltage, and the DC bus voltage is fluctuating. At the same time, the load resistance will change due to the influence of external uncertain factors. The above factors will have an adverse effect on the output voltage of the Buck converter. Therefore, a first state observer that considers the influence of load change on resistance change and a second state observer that considers the influence of voltage fluctuation caused by the DC bus can be set. In this way, the first interference estimation value caused by resistance change and the second interference estimation value caused by voltage fluctuation are determined.

[0049] As an optional embodiment, the first disturbance estimate value and the second disturbance estimate value are input into a complementary sliding mode controller to obtain a sliding mode control law, including: when the complementary sliding mode controller includes an integral sliding surface and a complementary sliding surface, determining a target integral sliding surface and a target complementary sliding surface based on the first disturbance estimate value and the second disturbance estimate value; determining the sliding mode control law based on the target integral sliding surface and the target complementary sliding surface.

[0050] In this embodiment, an integral sliding surface and a complementary sliding surface are involved, wherein the integral sliding surface is an integral term of a state variable added to a linear sliding surface. The introduction of the integral sliding surface can reduce the jitter and steady-state error of the system. The complementary sliding surface is orthogonal to the integral sliding surface. The two sliding surfaces are combined to transform the motion trajectory on a single sliding surface of a traditional SMC control system to the intersection of two orthogonal sliding surfaces. This control strategy can effectively shorten the time of the approach phase, reduce the tracking error of the system, weaken the jitter, and has strong robust performance. The complementary sliding surface orthogonal to it can enable the system to have a higher position tracking accuracy. The specific settings are introduced in the following optional implementation of the present invention and will not be repeated here.

[0051] As an optional embodiment, before determining the energy router system, it also includes: determining a first stability analysis function corresponding to the resistance change term, a second stability analysis function corresponding to the voltage fluctuation term, and a third stability analysis function corresponding to the complementary sliding mode controller; verifying the first convergence result of whether the resistance change term converges when the time tends to 0 according to the first stability analysis function, and the first positive and negative results of the first verification item, and verifying the second convergence result of whether the voltage fluctuation term converges when the time tends to 0 according to the second stability analysis function, and the second positive and negative results of the second verification item, and verifying the third positive and negative results of the third verification item of the complementary sliding mode controller according to the third stability analysis function; determining an elimination result according to the first convergence result, the first positive and negative results, the second convergence result, the second positive and negative results, and the third positive and negative results, wherein the elimination result is a result indicating whether the settings in the energy router system can eliminate the disturbance.

[0052] In this embodiment, a stability analysis function corresponding to the disturbance term is determined, wherein the stability analysis function may be a Lyapunov function, which is a mathematical tool widely used in control system theory and system dynamics, and is mainly used to analyze the stability and instability of nonlinear dynamic systems.

[0053] First, we can determine the equation corresponding to the interference term and select or construct a Lyapunov function V(x), where x is the state variable of the system. This function needs to satisfy positive definiteness and decreasingness (or negative definite derivatives). Calculate the derivative dV(x) / dt of the Lyapunov function V(x) with respect to time. This derivative should be able to represent the rate of change of the system state and should include the influence of the interference term. If dV(x) / dt is negative definite (that is, for all non-zero states x, dV(x) / dt<0), then the system is asymptotically stable, which means that the state of the system will converge to a certain equilibrium point (possibly the origin) over time. This indicates that the system state (which may include the influence of the interference term) is converging, so that the influence of the interference term in the system can be eliminated. Therefore, by determining the functions corresponding to the two interference terms, it can be determined whether the errors caused by them can be eliminated. Then the stability of the system can be better judged and set.

[0054] Among them, a third stability analysis function corresponding to the complementary sliding mode controller is also set. In addition to analyzing whether the above-mentioned disturbance can be eliminated, that is, in addition to determining the above-mentioned stability, the Lyapunov function can also be used to evaluate the controller's ability to suppress disturbances. If the derivative of the Lyapunov function remains negative when the system is disturbed, it indicates that the controller can effectively suppress disturbances and maintain the stability of the system. That is to say, the setting of the complementary sliding mode controller is also appropriate. Therefore, this embodiment is better analyzed and set through the stability function. The specific setting is introduced in the following optional implementation of the present invention and will not be repeated here.

[0055] As an optional embodiment, before determining the energy router system, it also includes: when the elimination result is that the disturbance cannot be eliminated, adjusting the load and the DC bus connected in the energy router system until an elimination result that can eliminate the disturbance is obtained.

[0056] In this embodiment, it is explained that when the elimination result is that the disturbance cannot be eliminated, the load and the DC bus connected in the energy router system are adjusted until an elimination result that can eliminate the disturbance is obtained. That is, the adjusted energy router system can eliminate the disturbance. Among them, when the elimination result is that the disturbance cannot be eliminated, it means that the resistance change caused by the load is too large, or the voltage fluctuation caused by the DC bus is too large, and the system is not enough to self-regulate. Therefore, in this case, the type of load currently connected, the power demand and its working state can be analyzed. Determine which loads may be the main cause of the disturbance, such as the sudden start or stop of high-power loads. According to the system monitoring results and load evaluation, a load adjustment strategy is formulated. Considering factors such as the priority, power demand, and working mode of the load, a suitable adjustment sequence and method are formulated. Gradually adjust the connection state of the load, such as switching the load, adjusting the load power, etc. During the adjustment process, continuously monitor the voltage and current state of the DC bus to ensure that the adjustment process does not cause too much impact on the system. After the load adjustment is completed, monitor the voltage and current state of the DC bus again. Verify whether the adjusted system has eliminated the disturbance and reached the expected stable state.

[0057] As an optional embodiment, before determining the energy router system, it also includes: determining an updated disturbance term causing disturbance in the energy router system; determining a third state observer corresponding to the updated disturbance term; connecting the third state observer to the energy router system to obtain an updated energy router system.

[0058] In this embodiment, factors other than the disturbance caused by the resistance change and voltage fluctuation caused by the load and the DC bus are also considered, that is, it is determined whether there is an updated disturbance item. If there is an updated disturbance item, the third state observer corresponding to the updated disturbance item is determined, so that the third state observer is connected to the system to eliminate the disturbances in the above three situations, thereby achieving a better effect of eliminating disturbances in the system.

[0059] Based on the above embodiments and optional embodiments, an optional implementation is provided, which is described in detail below.

[0060] An optional embodiment of the present invention provides an improved complementary sliding mode control method for a Buck converter at a load port of an energy router system. Figure 2 is a schematic diagram of an energy router system provided according to an optional embodiment of the present invention, Figure 3 This is a schematic diagram of the topological structure of a traditional BUCK converter in the prior art. Figure 4 is a control block diagram including an improved BUCK converter provided by an optional embodiment of the present invention, such as Figure 2 ,3,4,as shown, Figure 4 First, the inductor current and output voltage in the Buck circuit are collected and introduced into the designed extended state observation to obtain the disturbance and The input is input into the complementary sliding mode controller CSMC to obtain the sliding mode control law μ, and the sliding mode control law μ is compared with the triangle wave to obtain the PWM signal, and the switch tube is controlled by the PWM driver, and finally the output voltage of the Buck circuit is controlled. The method provided by the optional implementation mode of the present invention is introduced below.

[0061] In the energy router system, the DC load port usually adopts Buck converter to realize the conversion of voltage level to supply power to the DC load. Because it is connected to the DC bus, the input voltage is the DC bus voltage, and the DC bus voltage is fluctuating. At the same time, the load resistance will change due to the influence of external uncertain factors. The above factors will have an adverse effect on the output voltage of the Buck converter. Therefore, the present invention designs an improved complementary sliding mode control method for the Buck converter at the load port of the energy router system, which solves the problem of unstable output voltage caused by input voltage fluctuation and load change, and can quickly and accurately track the reference voltage. That is, it adopts an extended state observer to effectively estimate the system state and disturbance, and designs a complementary sliding mode control algorithm, which effectively improves the robustness and dynamic performance of the system, and obtains a higher precision steady-state tracking error.

[0062] The present invention is an improved complementary sliding mode control method for a Buck converter at a load port of an energy router system. The average state equation is derived from the topological structure diagram of the Buck converter as follows:

[0063]

[0064] where i L is the inductor current, V o is the output voltage, E is the input voltage, L is the inductance, C is the capacitance, and R is the load resistance.

[0065] In practical applications, the input voltage and load resistance of the Buck converter may change due to external interference, resulting in the output voltage deviating from the expected value, so in order to solve this problem.

[0066] The present invention introduces the principle of extended observer, and brings the changes caused by load resistance change and input voltage fluctuation into the average state equation of the Buck converter as disturbances, and obtains the following equation, that is, constructs the state space equation of the Buck converter with parameter uncertainty:

[0067]

[0068] in,

[0069] Among them, d1(t) is the disturbance caused by the change of load resistance, d2(t) is the disturbance caused by the fluctuation of input voltage, R0 is the per-unit value of load resistance, and E0 is the per-unit value of input voltage.

[0070] According to the extended state observer principle, an ESO can be constructed for the disturbance d1(t) and the disturbance d2(t), that is, the corresponding extended state observer is designed for the load disturbance and the input voltage fluctuation, as shown below:

[0071]

[0072] Among them, it is the formula corresponding to the first state observer, Z1 is the estimated value of the output voltage when the load resistance changes, Z2 is the estimated value of the load disturbance when the load resistance changes, β 11 , β 12 >0, is the observer parameter.

[0073]

[0074] Among them, it is the formula corresponding to the second state observer, Z3 is the estimated value of the inductor current under input voltage fluctuation, Z4 is the estimated value of the load disturbance under input voltage fluctuation, β 21 , β 22 >0, is the observer parameter.

[0075] According to equations (1) and (2), the estimated values ​​of the input voltage and load resistance of the actual system after the disturbance are as follows:

[0076]

[0077] In the formula, are the estimated values ​​of input voltage and load resistance respectively.

[0078] Based on the derived average state equation of the Buck converter containing the disturbance, a reasonable error variable is designed as follows:

[0079]

[0080] Define e1, e2 as the error variable of the output voltage and its differential, for The estimated value of .

[0081] Then, based on the obtained input voltage and the estimated value of the load resistance, according to the complementary sliding mode control principle, the sliding mode surface of the complementary sliding mode controller adopts the method of combining the integral sliding mode and the complementary sliding mode surface, that is, a complementary sliding mode controller is set. The integral sliding mode surface is defined as:

[0082]

[0083] Differentiating the integral sliding surface S1 yields:

[0084]

[0085] The complementary sliding surfaces are defined as:

[0086]

[0087] Differentiating the complementary sliding surface yields:

[0088]

[0089] Define the sum of the two sliding surfaces as σ, then the relationship between the two sliding surfaces is

[0090]

[0091] Right now

[0092] Secondly, to ensure that the system can approach the sliding surface from any state within a limited time, the exponential reaching law is selected as the switching control law. The selected exponential reaching law is as follows:

[0093] μ=-Ksgn(S1+S2)-ε(S1+S2) (14)

[0094] In the formula, ε, K>0.

[0095] For complementary sliding mode control, the Lyapunov function is defined as:

[0096]

[0097] By taking the derivative of the Lyapunov function and combining it with formula (13), we can obtain:

[0098]

[0099] According to the sliding mode control principle, the sliding mode control law is composed of the equivalent control term u eq And switch control u n Composition, namely:

[0100] μ=μ eq +μ n (17)

[0101]

[0102] μ n =-Ksgn(S1+S2)-ε(S1+S2)(19)

[0103] For a Buck converter with load disturbances and input voltage fluctuations, the ESO designed using equations (4)-(5) can achieve accurate estimation of the system states and disturbances.

[0104] The following error system is defined to conduct feasibility analysis of the control algorithm:

[0105]

[0106] Differentiate equations (20)-(21) and substitute equations (4)-(5) to obtain:

[0107]

[0108] First, for the disturbance d1(t), consider the following Lyapunov function, which is the same as the first stability analysis function mentioned above:

[0109]

[0110] Taking the derivative of V1, we get

[0111]

[0112] Substituting formula (23) into the equation, we can obtain:

[0113]

[0114] Similarly, for d2(t), consider the following Lyapunov function, which is the same as the second stability analysis function mentioned above:

[0115]

[0116] Taking the derivative of V2, we get

[0117]

[0118] Substituting formula (24) into the equation, we can obtain:

[0119]

[0120] For the convenience of theoretical analysis, assuming that the perturbations d1(t) and d2(t) are bounded, we have Because in equations (26) and (29), β 11 β 12 >0,β 21 β 22 > 0, therefore, the error systems (20) and (21) are ISS stable. At this time, note that This indicates that the error system will converge to zero in a finite time, which is the same as the first convergence result, the first positive and negative result, and the second convergence result, the second positive and negative result mentioned above.

[0121] For the designed complementary sliding mode controller, the following Lyapunov function is defined, which is the same as the third stability analysis function mentioned above.

[0122]

[0123] Solving the Lyapunov function and substituting it into equations (18)-(19) yields:

[0124]

[0125] From formula (31), we can see that the Lyapunov function So in Under the condition of , the system satisfies the Lyapunov stability condition, so that the system voltage error state estimation value and It can converge to the sliding surface in a finite time, and then converge to the equilibrium state in a finite time, that is, the same as the third positive and negative results mentioned above, to determine the elimination result, that is, to determine whether the settings in the energy router system can eliminate the disturbance result. If the disturbance can be eliminated, it means that the method is feasible, and the disturbance in the energy router system can be eliminated by this method to stabilize the voltage.

[0126] Through the above optional implementation, at least the following beneficial effects can be achieved:

[0127] (1) The extended state observer is used to accurately estimate load disturbances and input voltage fluctuations caused by external factors;

[0128] (2) The sliding mode control algorithm is improved by combining the integral sliding surface with the complementary sliding surface, which can effectively eliminate system chattering, reduce the system tracking error, improve the system tracking accuracy, and maintain the stable operation of the energy router system;

[0129] (3) Due to its high reliability, high efficiency, low cost and simple structure, DC / DC converters have been widely used in aerospace, uninterruptible power supply, automobile manufacturing, telecommunication equipment and other industrial fields. As a typical nonlinear system, DC / DC converters have high requirements on the performance and robustness of the voltage tracking controller. Sliding mode control is a commonly used nonlinear control strategy that aims to achieve stability and robustness control of the system. It controls the movement of the system state by introducing a specific sliding surface. The core idea is to enable the system state to slide quickly and accurately onto the sliding surface and keep moving on the surface. Due to its advantages such as insensitivity to external disturbances, rapid response, strong robustness and simple physical implementation, it is widely used in robotics, aerospace, industrial production and other fields.

[0130] It should be noted that, for the above-mentioned method embodiments, for the sake of simplicity, they are all described as a series of action combinations, but those skilled in the art should know that the present invention is not limited by the described action sequence, because according to the present invention, certain steps can be performed in other sequences or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by the present invention.

[0131] Through the description of the above implementation methods, those skilled in the art can clearly understand that the method according to the above embodiment can be implemented by means of software plus a necessary general hardware platform, and of course can also be implemented by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, a magnetic disk, or an optical disk), and includes a number of instructions for a terminal device (which can be a mobile phone, a computer, a server, or a network device, etc.) to execute the methods of various embodiments of the present invention.

[0132] Example 2

[0133] According to an embodiment of the present invention, a device for implementing the above-mentioned method for stabilizing voltage output is also provided. Figure 5is a structural block diagram of a device for stabilizing voltage output according to an embodiment of the present invention, such as Figure 5 As shown, the device includes: a first determination module 502, a second determination module 504, a third determination module 506, a regulation module 508 and a pressure supply module 510. The device is described in detail below.

[0134] A first determining module 502 is used to determine an energy router system, wherein the energy router system includes a voltage control circuit, a first state observer, a second state observer, and a complementary sliding mode controller, the voltage control circuit is connected to the load, the voltage control circuit is connected to the DC bus, the voltage control circuit is electrically connected to the first state observer and the second state observer respectively, the voltage control circuit is electrically connected to the complementary sliding mode controller, and the complementary sliding mode controller is electrically connected to the first state observer and the second state observer respectively;

[0135] A second determination module 504, connected to the first determination module 502, for determining a first disturbance estimation value corresponding to the first state observer and a second disturbance estimation value corresponding to the second state observer;

[0136] A third determination module 506, connected to the second determination module 504, is used to input the first disturbance estimation value and the second disturbance estimation value into a complementary sliding mode controller to obtain a sliding mode control law;

[0137] An adjustment module 508, connected to the third determination module 506, is used to adjust the reference pulse wideband modulation signal according to the sliding mode control law to determine the target pulse wideband modulation signal;

[0138] The voltage supply module 510 is connected to the regulating module 508 and is used to control the switch tube of the voltage control circuit according to the target pulse width modulation signal to supply voltage to the load.

[0139] It should be noted here that the above-mentioned first determination module 502, second determination module 504, third determination module 506, adjustment module 508 and pressure supply module 510 correspond to steps S102 to S110 in the method for implementing stable voltage output, and the instances and application scenarios implemented by the multiple modules and corresponding steps are the same, but are not limited to the contents disclosed in the above-mentioned embodiment 1.

[0140] Example 3

[0141] According to another aspect of an embodiment of the present invention, there is provided an electronic device, comprising: a processor; and a memory for storing instructions executable by the processor, wherein the processor is configured to execute the instructions to implement any of the above methods for stabilizing voltage output.

[0142] Example 4

[0143] According to another aspect of an embodiment of the present invention, a computer-readable storage medium is provided. When instructions in the computer-readable storage medium are executed by a processor of an electronic device, the electronic device can execute any of the above-mentioned methods for stabilizing voltage output.

[0144] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0145] In the above embodiments of the present invention, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0146] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of the units can be 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 interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

[0147] 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 units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0148] In addition, each functional unit in each embodiment of the present invention 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. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0149] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for 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 invention. The aforementioned storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, magnetic disk or optical disk and other media that can store program codes.

[0150] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for stabilizing voltage output, characterized in that: include: Determine an energy router system, wherein the energy router system includes a voltage control circuit, a first state observer, a second state observer, and a complementary sliding mode controller, the voltage control circuit is connected to a load, the voltage control circuit is connected to a DC bus, the voltage control circuit is electrically connected to the first state observer and the second state observer, respectively, the voltage control circuit is electrically connected to the complementary sliding mode controller, and the complementary sliding mode controller is electrically connected to the first state observer and the second state observer, respectively; determining a first disturbance estimate corresponding to the first state observer and a second disturbance estimate corresponding to the second state observer; Inputting the first disturbance estimation value and the second disturbance estimation value into the complementary sliding mode controller to obtain a sliding mode control law; Adjusting the reference pulse wideband modulation signal according to the sliding mode control law to determine the target pulse wideband modulation signal; The switch tube of the voltage control circuit is controlled according to the target pulse width modulation signal to supply voltage to the load.

2. The method according to claim 1, characterized in that Before deciding on the energy router system, also include: Determining, based on the voltage control circuit, a resistance change term corresponding to the resistance change caused by the load, and determining a voltage fluctuation term corresponding to the voltage fluctuation caused by the DC bus; The first state observer is determined according to the resistance change term, the second state observer is determined according to the voltage fluctuation term, and the complementary sliding mode controller is determined according to the resistance change term and the voltage fluctuation term.

3. The method according to claim 2, characterized in that Inputting the first disturbance estimation value and the second disturbance estimation value into the complementary sliding mode controller to obtain a sliding mode control law includes: In a case where the complementary sliding mode controller includes an integral sliding mode surface and a complementary sliding mode surface, determining a target integral sliding mode surface and a target complementary sliding mode surface according to the first disturbance estimation value and the second disturbance estimation value; The sliding mode control law is determined according to the target integral sliding mode surface and the target complementary sliding mode surface.

4. The method according to claim 2, characterized in that: Before deciding on the energy router system, also include: Determining a first stability analysis function corresponding to the resistance change term, a second stability analysis function corresponding to the voltage fluctuation term, and a third stability analysis function corresponding to the complementary sliding mode controller; Verifying a first convergence result of whether the resistance change term converges when the time approaches 0 and a first positive and negative result of the first verification term based on the first stability analysis function, and verifying a second convergence result of whether the voltage fluctuation term converges when the time approaches 0 and a second positive and negative result of the second verification term based on the second stability analysis function, and verifying a third positive and negative result of the third verification term of the complementary sliding mode controller based on the third stability analysis function; An elimination result is determined based on the first convergence result, the first positive and negative result, the second convergence result, the second positive and negative result, and the third positive and negative result, wherein the elimination result is a result indicating whether the settings within the energy router system can eliminate the disturbance.

5. The method according to claim 4, characterized in that Before deciding on the energy router system, also include: When the elimination result is that the disturbance cannot be eliminated, the load and the DC bus connected in the energy router system are adjusted until an elimination result that can eliminate the disturbance is obtained.

6. The method according to any one of claims 2 to 5, characterized in that Before deciding on the energy router system, also include: determining an updated disturbance term causing a disturbance in the energy router system; Determining a third state observer corresponding to the updated disturbance term; The third state observer is connected to the energy router system to obtain an updated energy router system.

7. A device for stabilizing voltage output, characterized in that: include: A first determining module is used to determine an energy router system, wherein the energy router system includes a voltage control circuit, a first state observer, a second state observer, and a complementary sliding mode controller, wherein the voltage control circuit is connected to a load, the voltage control circuit is connected to a DC bus, the voltage control circuit is electrically connected to the first state observer and the second state observer respectively, the voltage control circuit is electrically connected to the complementary sliding mode controller, and the complementary sliding mode controller is electrically connected to the first state observer and the second state observer respectively; a second determining module, configured to determine a first disturbance estimation value corresponding to the first state observer and a second disturbance estimation value corresponding to the second state observer; a third determining module, configured to input the first disturbance estimation value and the second disturbance estimation value into the complementary sliding mode controller to obtain a sliding mode control law; An adjustment module, used for adjusting a reference pulse wideband modulation signal according to the sliding mode control law to determine a target pulse wideband modulation signal; A voltage supply module is used to control the switch tube of the voltage control circuit according to the target pulse broadband modulation signal to supply voltage to the load.

8. An energy router system, characterized in that: include: A voltage control circuit, a first state observer, a second state observer, and a complementary sliding mode controller, wherein the voltage control circuit is connected to a load, the voltage control circuit is connected to a DC bus, the voltage control circuit is electrically connected to the first state observer and the second state observer respectively, the voltage control circuit is electrically connected to the complementary sliding mode controller, and the complementary sliding mode controller is electrically connected to the first state observer and the second state observer respectively.

9. An electronic device, characterized in that: include: processor; a memory for storing instructions executable by the processor; The processor is configured to execute the instructions to implement the method for stabilizing voltage output according to any one of claims 1 to 6.

10. A computer-readable storage medium, characterized in that: When the instructions in the computer-readable storage medium are executed by a processor of an electronic device, the electronic device is enabled to perform the method for stabilizing voltage output as claimed in any one of claims 1 to 6.

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