Output voltage ripple control method and related device of dual active bridge

Abstract

The present application proposes a method for controlling the output voltage ripple of a dual active bridge and a related device, the method comprising: a controller obtaining a plurality of first circuit parameters and the n-1th ripple voltage peak-to-peak value under the current working condition, the plurality of first circuit parameters including a plurality of frequency-jittering-related frequency values ​​and a first phase shift angle; determining a phase shift angle control variable based on the n-1th ripple voltage peak-to-peak value; determining a second phase shift angle based on the phase shift angle control variable, the n-1th ripple voltage peak-to-peak value, the nth ripple voltage peak-to-peak value and the first phase shift angle; determining a target phase shift angle based on the second phase shift angle and a plurality of frequency-jittering-related frequency values; and performing a phase shift angle compensation operation based on the target phase shift angle when the frequency-jittering cycle reaches the n+1th frequency-jittering cycle. In this way, when a phase shift angle reverse compensation operation is performed based on the ripple voltage peak-to-peak value to offset the power transmission error caused by the frequency offset, the output power imbalance problem at the moment of frequency change is greatly alleviated, and the degree of deterioration of the output voltage ripple is reduced.

Description

Technical Field

[0001] The present invention relates to the field of power electronics technology, and in particular to an output voltage ripple control method of a dual active bridge and a related device. Background Art

[0002] With the rapid development of the new energy industry, dual active bridge (DAB) converters, due to their efficient bidirectional energy transmission capabilities, have become a key power electronic device for electric vehicle fast charging and energy storage systems. In DAB converters, the rapid on / off action of high-frequency switching devices generates extremely high rates of change of current and voltage, leading to voltage spikes and current harmonics at the switch nodes. These disturbances propagate through conduction and radiation, causing electromagnetic interference (EMI). To suppress EMI caused by high-frequency switching, frequency-jittering control technology dynamically adjusts the switching frequency to disperse harmonic energy, and has become a mainstream EMI solution in switching power supply design.

[0003] However, the power transmission characteristics of the dual active bridge converter dictate that its maximum output power is highly correlated with the switching frequency, with actual output power achieved by adjusting the phase-shift angle. With the addition of frequency-jittering technology, the switching frequency will periodically fluctuate. To maintain the target output power, the phase-shift angle must compensate for frequency changes in real time. However, this dynamic adjustment process exposes the problem of increased output voltage ripple in actual operation. This is due to the sudden change in switching frequency and the delayed response of the phase-shift angle control loop, resulting in an imbalance in power output and the formation of low-frequency voltage ripple on the output side. The introduction of frequency-jittering technology in the dual active bridge converter leads to a significant deterioration in output voltage ripple, a contradiction that limits the application of dual active bridge converters.

[0004] At present, the main methods used to suppress the deterioration of voltage ripple are to increase the output filter network or limit the frequency jitter range. However, this will lead to an increase in the cost and volume of the converter, weaken the EMI improvement effect, and make it difficult to meet the requirements of some standards. In turn, the dynamic coupling relationship between the switching frequency and the output power is not decoupled or weakened, and the output power is unbalanced at the moment of frequency change, which in turn leads to the problem that the deterioration of output voltage ripple cannot be optimized from the control level. Summary of the Invention

[0005] The embodiments of the present application provide a method and related apparatus for controlling output voltage ripple of a dual active bridge, which can greatly alleviate the output power imbalance problem at the moment of frequency change and reduce the degree of deterioration of the output voltage ripple.

[0006] In a first aspect, an embodiment of the present application provides a method for controlling output voltage ripple of a dual active bridge, which is applied to a controller of a dual active bridge system, comprising:

[0007] Obtaining multiple first circuit parameters and an (n-1)th ripple voltage peak-to-peak value under a current operating condition, where the (n-1)th ripple voltage peak-to-peak value is the difference between a peak value and a valley value of the ripple voltage in an (n-1)th frequency jittering cycle. The multiple first circuit parameters include multiple frequency jittering-related frequency values ​​and a first phase shift angle, where the first phase shift angle is a maximum compensated phase shift angle in the (n-1)th frequency jittering cycle, where n is an integer greater than or equal to 2.

[0008] Determining a phase shift angle control variable based on the (n-1)th ripple voltage peak-to-peak value;

[0009] determining a second phase shift angle based on the phase shift angle control variable, the (n-1)th ripple voltage peak-to-peak value, the (n)th ripple voltage peak-to-peak value, and the first phase shift angle, wherein the second phase shift angle is the optimal compensation phase shift angle within the (n)th frequency jittering cycle under the current operating condition, and the (n)th ripple voltage peak-to-peak value is the difference between the peak value and the valley value of the ripple voltage within the (n)th frequency jittering cycle;

[0010] A target phase shift angle is determined based on the second phase shift angle and the multiple frequency jittering-related frequency values, where the target phase shift angle is used to perform phase shift angle compensation. When the frequency jittering cycle reaches the (n+1)th frequency jittering period, a phase shift angle compensation operation is performed based on the target phase shift angle to reduce the offset degree of the output voltage ripple.

[0011] In a possible embodiment, determining the second phase shift angle based on the phase shift angle control variable, the (n-1)th ripple voltage peak-to-peak value, the (n)th ripple voltage peak-to-peak value, and the first phase shift angle includes:

[0012] determining a third phase shift angle based on the first phase shift angle and the phase shift angle control variable;

[0013] Performing a compensation operation based on the third phase shift angle to obtain an nth ripple voltage peak-to-peak value generated based on the third phase shift angle compensation;

[0014] determining a phase shift angle adjustment strategy based on the nth ripple voltage peak-to-peak value and the n-1th ripple voltage peak-to-peak value, wherein the phase shift angle adjustment strategy is used to adjust the first phase shift angle based on the phase shift angle control variable;

[0015] The second phase shift angle is determined based on the phase shift angle adjustment strategy and the first phase shift angle.

[0016] In a possible embodiment, determining the phase shift angle adjustment strategy based on the nth ripple voltage peak-to-peak value and the (n-1)th ripple voltage peak-to-peak value includes:

[0017] If the nth ripple voltage peak-to-peak value is less than the n-1th ripple voltage peak-to-peak value, determining that the phase shift angle adjustment strategy is to perform a summation operation based on the phase shift angle control variable and the first phase shift angle;

[0018] If the peak-to-peak value of the nth ripple voltage is greater than the peak-to-peak value of the (n-1)th ripple voltage, it is determined that the phase shift angle adjustment strategy is to perform a difference operation based on the phase shift angle control variable and the first phase shift angle.

[0019] In a possible embodiment, determining the phase shift angle control variable based on the (n-1)th ripple voltage peak-to-peak value includes:

[0020] Acquiring a plurality of second circuit parameters under a current working condition, wherein the second circuit parameters include performance parameters of the dual active bridge system, wherein the performance parameters include response speed parameters and / or stability parameters;

[0021] determining a phase shift angle control parameter based on the second circuit parameter, wherein the phase shift angle control parameter is associated with the plurality of second circuit parameters of the dual active bridge system;

[0022] The phase shift angle control variable is determined based on the phase shift angle control parameter and the (n-1)th ripple voltage peak-to-peak value.

[0023] In a possible embodiment, determining the phase shift angle control parameter based on the second circuit parameter includes:

[0024] Determining a transfer function based on a preset small signal model and circuit information parameters, wherein the transfer function is used to reflect the dynamic impact of a duty cycle disturbance on the output voltage, wherein the duty cycle disturbance is a disturbance generated by regulating the first phase shift angle based on the phase shift angle control variable;

[0025] The phase shift angle control parameter is determined based on the transfer function, the control parameter control calculation model and the second circuit parameter. The control parameter calculation model is used to constrain the association between the phase shift angle control parameter and the multiple second circuit parameters and the control parameter boundary threshold. The control parameter boundary threshold is used to constrain the maximum and minimum values ​​of the phase shift angle control parameter.

[0026] In a possible embodiment, determining the phase shift angle control variable based on the (n-1)th ripple voltage peak-to-peak value further includes:

[0027] determining a first simulation result based on the phase shift angle control parameter and a preset simulation control model, wherein the first simulation result is used to characterize a change trend of an nth peak-to-peak value of the simulated ripple voltage of the dual active bridge system when the phase shift angle control parameter is adopted, and the preset simulation control model is a model for simulating the dual active bridge system;

[0028] determining an nth simulation response rate parameter based on the first simulation result, the nth simulation response rate parameter being used to characterize a response speed of the nth ripple voltage peak-to-peak value simulation value within a preset time length, where the preset time length is a preset expected response time length;

[0029] If the nth simulation response rate parameter is not within the preset response rate threshold range, fine-tuning is performed based on the phase shift angle control variable; if the nth simulation response rate parameter is within the preset response rate threshold range, the phase shift angle control variable is determined.

[0030] In a possible embodiment, the multiple frequency jittering-related frequency values ​​include at least one of a switching frequency, a frequency jittering frequency, a frequency jittering frequency upper limit, and a frequency jittering frequency lower limit. The switching frequency is a dynamically changing quantity, and the frequency jittering frequency, the frequency jittering frequency upper limit, and the frequency jittering frequency lower limit are static quantities. Determining the target phase shift angle based on the second phase shift angle and the multiple frequency jittering-related frequency values ​​includes:

[0031] The proportional coefficient is determined based on the second phase shift angle, the upper limit of the frequency jittering frequency, the lower limit of the frequency jittering frequency, and a proportional coefficient formula, wherein the proportional coefficient formula includes: ,in, is the proportionality coefficient, is the second phase shift angle, is the upper limit of the frequency jittering, is the lower limit of the frequency jittering;

[0032] The target phase shift angle is determined based on the proportional coefficient, the switching frequency, the frequency jittering frequency, and a target phase shift angle formula, wherein the target phase shift angle formula includes: , where f is the switching frequency, is the frequency jittering frequency.

[0033] In a second aspect, an embodiment of the present application provides an output voltage ripple control device for a dual active bridge, which is applied to a controller of a dual active bridge system. The device includes:

[0034] an acquisition module, configured to acquire a plurality of first circuit parameters and an (n-1)th ripple voltage peak-to-peak value under a current operating condition, where the (n-1)th ripple voltage peak-to-peak value is the difference between a peak value and a valley value of the ripple voltage in an (n-1)th frequency jittering cycle; the plurality of first circuit parameters include a plurality of frequency jittering-related frequency values ​​and a first phase shift angle, where the first phase shift angle is a maximum compensated phase shift angle in an (n-1)th frequency jittering cycle, where n is an integer greater than or equal to 2;

[0035] A first determining module is configured to determine a phase shift angle control variable based on the (n-1)th ripple voltage peak-to-peak value;

[0036] a second determination module, configured to determine a second phase shift angle based on the phase shift angle control variable, the (n-1)th ripple voltage peak-to-peak value, the (n)th ripple voltage peak-to-peak value, and the first phase shift angle, wherein the second phase shift angle is the optimal compensation phase shift angle within the (n)th frequency jittering cycle under the current operating condition, and the (n)th ripple voltage peak-to-peak value is the difference between the peak value and the valley value of the ripple voltage within the (n)th frequency jittering cycle;

[0037] a third determination module, configured to determine a target phase shift angle based on the second phase shift angle and the multiple frequency jittering-related frequency values, where the target phase shift angle is a phase shift angle used for phase shift angle compensation; and, when the frequency jittering cycle reaches the (n+1)th frequency jittering cycle, perform a phase shift angle compensation operation based on the target phase shift angle to reduce the offset degree of the output voltage ripple.

[0038] In a third aspect, an embodiment of the present application provides a computer-readable storage medium on which an output voltage ripple control program for a dual active bridge is stored. The output voltage ripple control program for the dual active bridge includes execution instructions. When the execution instructions are executed by a processor, the processor executes some or all of the steps described in the first aspect.

[0039] In a fourth aspect, an embodiment of the present application provides an electronic device comprising a processor, a memory, a communication interface, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the processor. When the one or more programs are executed by the processor, the processor performs some or all of the steps described in the first aspect.

[0040] In a fifth aspect, embodiments of the present application provide a computer program product, wherein the computer program product includes a non-transitory computer-readable storage medium storing a computer program, wherein the computer program is operable to cause a computer to perform some or all of the steps described in the first aspect of the embodiments of the present application. The computer program product may be a software installation package.

[0041] By implementing the embodiment of the present application, the controller obtains multiple first circuit parameters and the n-1th ripple voltage peak-to-peak value under the current working condition, the n-1th ripple voltage peak-to-peak value is the difference between the peak value and the valley value of the ripple voltage in the n-1th frequency jittering cycle, the multiple first circuit parameters include multiple frequency jittering-related frequency values ​​and a first phase shift angle, the first phase shift angle is the maximum compensation phase shift angle in the n-1th frequency jittering cycle, where n is an integer greater than or equal to 2; based on the n-1th ripple voltage peak-to-peak value, the phase shift angle control variable is determined; based on the phase shift angle control variable, the n-1th ripple voltage peak-to-peak value, the phase shift angle control variable is determined; based on the phase shift angle control variable, the n-1th ripple voltage peak-to-peak value, the phase shift angle control variable is determined. The second phase shift angle is determined based on the value, the nth ripple voltage peak-to-peak value, and the first phase shift angle. The second phase shift angle is the optimal compensation phase shift angle within the nth frequency jittering cycle under the current operating condition. The nth ripple voltage peak-to-peak value is the difference between the peak and valley values ​​of the ripple voltage within the nth frequency jittering cycle. A target phase shift angle is determined based on the second phase shift angle and the multiple frequency jittering-related frequency values. The target phase shift angle is the phase shift angle used for phase shift angle compensation. When the frequency reaches the (n+1)th frequency jittering cycle, a phase shift angle compensation operation is performed based on the target phase shift angle to reduce the degree of output voltage ripple offset. In this way, when a phase shift angle reverse compensation operation is performed based on the peak-to-peak value of the ripple voltage to offset the power transmission error caused by frequency offset, the output power imbalance problem at the moment of frequency change is greatly alleviated, and the deterioration of the output voltage ripple is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the background technology, the drawings required for use in the embodiments of the present invention or the background technology will be described below.

[0043] Figure 1a 1 is a schematic diagram of the architecture of a dual active bridge system provided in an embodiment of the present application;

[0044] Figure 1b This is a schematic diagram of the architecture of a dual active bridge main circuit module provided in an embodiment of the present application;

[0045] Figure 2 1 is a flow chart of a method for controlling output voltage ripple of a dual active bridge provided in an embodiment of the present application;

[0046] Figure 3 This is a schematic diagram of a process for determining a phase shift angle control variable provided by an embodiment of the present application;

[0047] Figure 4 1 is a flow chart of another method for controlling output voltage ripple of a dual active bridge provided in an embodiment of the present application;

[0048] Figure 5 1 is a schematic structural diagram of an output voltage ripple control device of a dual active bridge proposed in an embodiment of the present application;

[0049] Figure 6 1 is a schematic structural diagram of another dual active bridge output voltage ripple control device provided in an embodiment of the present application;

[0050] Figure 7 This is a structural diagram of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0051] In order to enable those skilled in the art to better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. 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 this application.

[0052] The terms "first," "second," and the like in the specification and claims of this application and the accompanying drawings are used to distinguish between different objects, not to describe a specific order. Furthermore, the terms "including," "having," and any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or electronic device comprising a series of steps or units is not limited to the listed steps or units, but may, in an optional example, also include steps or units not listed, or may, in an optional example, include other steps or units inherent to the process, method, product, or electronic device.

[0053] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0054] The power transfer characteristics of the dual active bridge converter dictate that its maximum output power is highly correlated with the switching frequency, with actual output power achieved by adjusting the phase-shift angle. The addition of frequency-jittering technology causes periodic fluctuations in the switching frequency. To maintain the target output power, the phase-shift angle must compensate for frequency variations in real time. However, this dynamic adjustment process exposes the problem of increased output voltage ripple in actual operation. This is due to the delay between the sudden change in switching frequency and the response of the phase-shift angle control loop, resulting in an imbalance in power output and the formation of low-frequency voltage ripple on the output side. The introduction of frequency-jittering technology in the dual active bridge converter significantly worsens the output voltage ripple, a contradiction that limits the application of dual active bridge converters.

[0055] At present, the main methods used to suppress the deterioration of voltage ripple are to increase the output filter network or limit the frequency jitter range. However, this will lead to an increase in the cost and volume of the converter, weaken the EMI improvement effect, and make it difficult to meet the requirements of some standards. In turn, the dynamic coupling relationship between the switching frequency and the output power is not decoupled or weakened, and the output power is unbalanced at the moment of frequency change, which in turn leads to the problem that the deterioration of output voltage ripple cannot be optimized from the control level.

[0056] In response to the above problems, an embodiment of the present application provides an output voltage ripple control method and related devices for a dual active bridge. When a phase shift angle reverse compensation operation is performed based on the peak-to-peak value of the ripple voltage to offset the power transmission error caused by the frequency offset, the output power imbalance problem at the moment of frequency change is greatly alleviated, and the deterioration of the output voltage ripple is reduced.

[0057] The output voltage ripple control method of the dual active bridge provided in the embodiment of the present application can be applied to Figure 1a In the dual active bridge system shown in Figure 1a , Figure 1a 1 is a schematic diagram of the architecture of a dual active bridge system provided in an embodiment of the present application. The dual active bridge system 100 includes a dual active bridge main circuit module 110 and a controller 120. The dual active bridge main circuit module 110 can communicate with the controller 120 through a network and accept the control of the controller 120.

[0058] In this solution, controller 120 refers to a computer used to process large amounts of computing tasks, store data, and perform control operations. In this solution, multiple models are deployed on controller 120. Controller 120 can also collect data from the models during use to control the output voltage ripple of the dual active bridge. Controller 120 can send control information to the dual active bridge main circuit module 110, causing the corresponding components in the dual active bridge main circuit module 110 to operate according to the obtained phase shift angle compensation values.

[0059] See also Figure 1b , Figure 1b Schematic diagram of the architecture of a dual active bridge main circuit module provided in an embodiment of the present application, such as Figure 1b As shown, the forward transmission direction is defined as arrive The dual active bridge main circuit module 110 includes an input DC source voltage , output voltage , Input bus filter capacitor , output bus filter capacitor , multiple switching tubes, energy storage inductors , DC blocking capacitors and , main transformer ; Among them, multiple switching tubes include , It is the primary side energy transfer switch tube, For the secondary side energy transfer switch tube, the main transformer The transformation ratio is n:1; the dual active bridge transmission power is ,in, is the switching frequency, D is the phase shift angle of the original secondary side square wave voltage, and its output power is related to the input voltage, output voltage and frequency. After adding the frequency jitter control, the switching frequency When input and output voltages remain constant due to periodic changes over time, the output power and switching frequency will exhibit periodic variations due to delays in the phase-shift control loop. This results in lower transmission power and lower output voltage as the frequency increases, and higher transmission power and higher output voltage as the frequency decreases. Based on the above architecture, this solution proposes a dual-active bridge control strategy under frequency-jittering control to regulate and compensate for the aforementioned phase-shift angle.

[0060] Based on this, the present application provides an output voltage ripple control method and related devices for a dual active bridge, and the present application is described in detail below with reference to the accompanying drawings.

[0061] See also Figure 2 , Figure 2 This is a flow chart of a method for controlling output voltage ripple of a dual active bridge provided in an embodiment of the present application, which is applied to a controller of a dual active bridge system, such as Figure 2 As shown, the method includes the following steps:

[0062] S210, obtaining multiple first circuit parameters and the (n-1)th ripple voltage peak-to-peak value under the current operating conditions, where the (n-1)th ripple voltage peak-to-peak value is the difference between the peak value and the valley value of the ripple voltage in the (n-1)th frequency jittering cycle. The multiple first circuit parameters include multiple frequency jittering-related frequency values ​​and a first phase shift angle, where the first phase shift angle is the maximum compensated phase shift angle in the (n-1)th frequency jittering cycle, where n is an integer greater than or equal to 2.

[0063] The current operating condition refers to the actual operating state of a power electronic device (such as a DC-DC converter or inverter) at a specific moment, including parameters such as input voltage, load, and switching frequency. The peak-to-peak ripple voltage refers to the difference between the peak and valley values ​​of the ripple component in the output voltage, reflecting the amplitude of the voltage fluctuation. The frequency jittering cycle refers to the period during which the switching frequency is dynamically adjusted, typically used for soft switching optimization or efficiency regulation. The first circuit parameters are circuit parameters related to frequency jittering control, including the frequency jittering-related value and the first phase shift angle. These parameters are numbered sequentially (n=2, 3, ...), with the n-1th frequency jittering cycle representing a period within the entire time-varying cycle. If the current period is within the nth frequency jittering cycle, the maximum phase shift angle (i.e., the first phase shift angle) obtained by the control strategy or closed-loop feedback within the n-1th frequency jittering cycle is used to calculate the specific phase shift angle to be compensated.

[0064] S220: Determine a phase shift angle control variable based on the (n-1)th ripple voltage peak-to-peak value.

[0065] Among them, the phase shift angle control variable is associated with the current working condition and the actual situation of the dual active bridge system; the phase shift angle control variable is used to determine the second phase shift angle, the phase shift angle control variable can be dynamically determined, and the phase shift angle control variable is a variable constant value.

[0066] In a possible embodiment, determining the phase shift angle control variable based on the peak-to-peak value of the (n-1)th ripple voltage includes:

[0067] Acquire multiple second circuit parameters under the current operating conditions, the second circuit parameters including performance parameters of the dual active bridge system, the performance parameters including a response speed parameter and / or a stability parameter; determine a phase shift angle control parameter based on the second circuit parameters, the phase shift angle control parameter being associated with the multiple second circuit parameters of the dual active bridge system; and determine the phase shift angle control variable based on the phase shift angle control parameter and the (n-1)th ripple voltage peak-to-peak value.

[0068] Among them, the second circuit parameter can be determined based on the small signal model, or can be directly obtained and preset. The above-mentioned small signal model can be a pre-trained model based on the circuit topology and related circuit information. The second circuit parameter can be a performance parameter of the dual active bridge system. The performance parameter can be used to characterize the transmission speed, stability and other performance of the dual active bridge system. The performance parameter can be at least one of a response speed parameter and a stability parameter. Among them, the response speed parameter can be a bandwidth , the phase shift angle control variable can be the phase margin , where bandwidth The higher the phase margin, the better the system's ability to track fast inputs. The higher the value, the stronger the system's ability to resist interference and model uncertainty. However, excessive bandwidth may amplify noise and cause overshoot or oscillation, and excessive phase margin may sacrifice response speed (e.g., reduce bandwidth). The above-mentioned second circuit parameters are dynamically variable. When the circuit is regulated based on certain parameters, such as the target phase shift angle required by this solution, the actual second circuit parameters in the circuit may also change. The changed second circuit parameters can be determined based on the current actual situation within each frequency jittering cycle.

[0069] The phase-shift angle control parameter is associated with the second circuit parameters. Specifically, the phase-shift angle control parameter and the plurality of second circuit parameters have a proportional relationship, and a value of the phase-shift angle control parameter is determined based on this proportional relationship. The phase-shift angle control variable is then obtained by controlling the phase-shift angle control parameter and the peak-to-peak value of the (n-1)th ripple voltage.

[0070] The phase shift angle control variable can be determined based on the following formula, the phase shift angle control parameter, and the peak-to-peak value of the n-1th ripple voltage: D cycle =k×V pp (n-1), where D cycle is the phase shift angle control variable, k is the phase shift angle control parameter, V pp (n-1) is the peak-to-peak value of the n-1th ripple voltage. The phase shift angle control parameter k that can be dynamically controlled and the D that is dynamically determined based on the dynamic control k cycle The compensation of the phase shift angle can be made more accurate.

[0071] If a small signal model is used to determine multiple second circuit parameters, the small signal model is first determined. The small signal model is constructed based on an equivalent circuit of an actual dual active bridge system. The equivalent circuit includes multiple key operating variables, including duty cycle D, input voltage V g , load current I o In the model, small signal perturbations are applied to the above-mentioned key working variables: , , ,in, , , is the small signal disturbance, , , is the key working variable in steady state; Taylor expansion is performed on the above equations and the first-order small signal terms are retained, while the higher-order terms are ignored to obtain multiple linearized equations. Then, the linearized equations are converted into equivalent circuit models. Circuit analysis methods (such as Kirchhoff's law and Laplace transform) are applied to the small signal equivalent circuit to obtain the output variables and the input variables. The transfer function is determined based on the output variables and the input variables. The transfer function is ,in, is the output variable, is the input variable. The transfer function describes the duty cycle disturbance Output voltage disturbance The dynamic influence of the k value is such that the determination of the k value satisfies the requirement of not having a bad influence on the output voltage.

[0072] Among them, if proportional control is adopted, the second circuit parameters include bandwidth , based on bandwidth Substituting into the transfer function, the method for determining the k value can be as follows: First, obtain a preset k value, or the k determined in the n-1th frequency jitter cycle, and then based on this (such as ), gradually increase and observe the system response. When the load suddenly changes, the output voltage recovery time is short and there is no oscillation; in steady state, the ripple V pp Meet the requirements.

[0073] It can be seen that in this embodiment, the phase shift angle control parameter k that can be dynamically controlled and the D that is dynamically determined based on the dynamic control k are cycle This allows for more accurate phase-shift angle compensation. Furthermore, when reverse compensation is performed based on the peak-to-peak value of the ripple voltage to offset the power transmission error caused by frequency offset, the output power imbalance problem at the moment of frequency change is greatly reduced, minimizing the deterioration of the output voltage ripple.

[0074] In a possible embodiment, determining the phase shift angle control parameter based on the second circuit parameter includes: determining a transfer function based on a preset small signal model and circuit information parameters, the transfer function being used to reflect the dynamic impact of duty cycle disturbance on the output voltage, the duty cycle disturbance being the disturbance generated by controlling the first phase shift angle based on the phase shift angle control variable; determining the phase shift angle control parameter based on the transfer function, the control parameter control calculation model and the second circuit parameter, the control parameter calculation model being used to constrain the correlation between the phase shift angle control parameter and the multiple second circuit parameters and the control parameter boundary threshold, the control parameter boundary threshold being used to constrain the maximum and minimum values ​​of the phase shift angle control parameter.

[0075] Among them, the specific description of the small signal model can refer to the specific explanation in the above embodiment, which will not be repeated here. The control parameter calculation model is used to constrain the relationship between the phase shift angle control parameter and multiple second circuit parameters and the control parameter boundary threshold. Ensure that the phase shift angle control parameter k does not exceed the preset maximum and minimum values ​​of the phase shift angle control parameter k to avoid system out of control. The boundary threshold is used to limit the value range of the phase shift angle control parameter k, for example: the maximum value k max: Prevent excessive phase shift angle from causing soft switching conditions to deteriorate or switching losses to increase; minimum value k min :Prevent the phase shift angle from being too small, which will cause the ripple voltage to increase or the efficiency to decrease. If the k value is greater than the maximum value k max , then the output k = maximum value k max ; If the detected k value is less than the minimum value k min , then the output k = minimum value k min .

[0076] As can be seen, in this embodiment, the impact of duty cycle disturbances on the output voltage is analyzed using a small-signal model and transfer function. The phase-shift angle control parameter k is dynamically adjusted in conjunction with real-time circuit parameters and a control model, and boundary threshold constraints are implemented to ensure stable system operation. Furthermore, by performing reverse phase-shift compensation based on the peak-to-peak value of the ripple voltage to offset power transmission errors caused by frequency offset, the output power imbalance caused by frequency changes is significantly mitigated, reducing the severity of output voltage ripple.

[0077] In one possible embodiment, see Figure 3 , Figure 3 This is a flow chart of determining a phase shift angle control variable provided by an embodiment of the present application, such as Figure 3 As shown, the determining of the phase shift angle control variable based on the peak-to-peak value of the n-1th ripple voltage further includes:

[0078] S221. Determine a first simulation result based on the phase shift angle control parameter and a preset simulation control model, wherein the first simulation result is used to characterize a change trend of the nth ripple voltage peak-to-peak value simulation value of the dual active bridge system when the phase shift angle control parameter is adopted, and the preset simulation control model is a model that simulates the dual active bridge system; determine an nth simulation response rate parameter based on the first simulation result, wherein the nth simulation response rate parameter is used to characterize a response speed of the nth ripple voltage peak-to-peak value simulation value within a preset time length, and the preset time length is a preset expected response time length.

[0079] S222: If the nth simulation response rate parameter is not within a preset response rate threshold range, fine-tune the variable based on the phase shift angle control.

[0080] S223: If the nth simulation response rate parameter is within a preset response rate threshold range, determining the phase shift angle control variable.

[0081] Among them, the pre-established dual-active bridge system dynamic model is used to simulate the effect of the phase shift angle Dn on the ripple voltage. The pre-established dual-active bridge system dynamic model is associated with the above-mentioned small signal model. The determined phase shift angle control variable is input into the dual-active bridge system dynamic model. By inputting the k value, the simulated value of the nth ripple is predicted, and its change trend (such as the rise / fall rate) is analyzed, that is, the nth simulated response rate parameter. The nth simulated response rate parameter can be determined by data analysis or by linear fitting, which is not limited here. The specific determination method can be through the following formula:

[0082] ;

[0083] in, is the nth simulation response rate parameter, is the first simulation result, T PP is the preset time length. n The larger the value, the higher the ripple PP The faster the internal changes (possibly overshoot or oscillation); R n The smaller it is, the slower the ripple changes (response lag). PP Usually it matches the control cycle or system dynamic characteristics, that is, it can correspond to the frequency jitter cycle. n The response is too slow, that is, , increase k to speed up the response; if Responding too quickly, , reduce k to slow down the change. After fine-tuning, re-simulate until R n Entering the preset response rate threshold range .like , confirm that the current k is a valid control variable and is applied to the actual system.

[0084] It can be seen that in this embodiment, by simulating the control model to predict the impact of the determined d value on the phase shift angle and ripple voltage, and combining it with the response rate parameter to evaluate the regulation effect, the optimal k value can be quickly determined and output, avoiding overshoot or oscillation caused by blind adjustment in the actual system. In addition, the combination of feedforward parameters and multiple constraints can make the k value determination more stable and reliable. Furthermore, when the phase shift angle reverse compensation operation is performed based on the peak-to-peak value of the ripple voltage to offset the power transmission error caused by frequency offset, the output power imbalance problem at the moment of frequency change is greatly alleviated, reducing the degree of deterioration of the output voltage ripple.

[0085] S230, determining a second phase shift angle based on the phase shift angle control variable, the (n-1)th ripple voltage peak-to-peak value, the nth ripple voltage peak-to-peak value, and the first phase shift angle, where the second phase shift angle is the optimal compensation phase shift angle within the nth frequency jittering cycle under the current operating condition, and the nth ripple voltage peak-to-peak value is the difference between the peak value and the valley value of the ripple voltage within the nth frequency jittering cycle.

[0086] A phase shift angle for the current nth frequency jittering cycle is determined based on the phase shift angle control variable determined above and the first phase shift angle. Specifically, the phase shift angle control variable may be increased or decreased based on the first phase shift angle. The current nth frequency jittering cycle is then performed based on this to obtain the nth peak-to-peak value of the ripple voltage in the current nth frequency jittering cycle.

[0087] Among them, based on the relationship between the peak-to-peak value of the nth ripple voltage and the peak-to-peak value of the n-1th ripple voltage, the phase shift angle adjustment strategy is determined. Specifically, the relationship between the peak-to-peak value of the nth ripple voltage and the peak-to-peak value of the n-1th ripple voltage can be: the peak-to-peak value of the nth ripple voltage is greater than the peak-to-peak value of the n-1th ripple voltage, or the peak-to-peak value of the nth ripple voltage is less than the peak-to-peak value of the n-1th ripple voltage. The phase shift angle adjustment strategy can be to increase or subtract the phase shift angle control variable, based on which, the second phase shift angle is determined, and the second phase shift angle is the optimal compensation phase shift angle for the n+1th frequency jittering cycle. It should be noted that in the n+1th frequency jittering cycle, all the above steps are performed based on the second phase shift angle, that is, the scheme is a repeated cycle process, and the above operations are performed in each cycle, so that the phase shift angle becomes more and more accurate, and the offset degree of the output voltage ripple is minimized to the greatest extent.

[0088] In a possible embodiment, determining the second phase shift angle based on the phase shift angle control variable, the n-1th ripple voltage peak-to-peak value, the nth ripple voltage peak-to-peak value and the first phase shift angle includes: determining a third phase shift angle based on the first phase shift angle and the phase shift angle control variable; performing a compensation operation based on the third phase shift angle to obtain an nth ripple voltage peak-to-peak value generated based on the third phase shift angle compensation; determining a phase shift angle adjustment strategy based on the nth ripple voltage peak-to-peak value and the n-1th ripple voltage peak-to-peak value, the phase shift angle adjustment strategy being used to adjust the first phase shift angle based on the phase shift angle control variable; and determining the second phase shift angle based on the phase shift angle adjustment strategy and the first phase shift angle.

[0089] Among them, based on the first phase shift angle plus or minus the phase shift angle control variable, the third phase shift angle is determined: D max(n) =D max(n-1) +D cycle（n-1） , where D cycle（n-1） is the phase shift angle control variable, D max(n-1) is the first phase shift angle, D max(n)The third phase shift angle is controlled based on the third phase shift angle. The nth ripple voltage peak-to-peak value is then obtained. A determination is made as to whether the nth ripple voltage peak-to-peak value is greater than the n-1th ripple voltage peak-to-peak value, or whether the nth ripple voltage peak-to-peak value is less than the n-1th ripple voltage peak-to-peak value. If the nth ripple voltage peak-to-peak value is greater than the n-1th ripple voltage peak-to-peak value, the phase shift angle adjustment strategy is to subtract the phase shift angle control variable. If the nth ripple voltage peak-to-peak value is less than the n-1th ripple voltage peak-to-peak value, the phase shift angle adjustment strategy is to add the phase shift angle control variable.

[0090] Specifically, determining the phase shift angle adjustment strategy based on the nth ripple voltage peak-to-peak value and the n-1th ripple voltage peak-to-peak value includes: if the nth ripple voltage peak-to-peak value is less than the n-1th ripple voltage peak-to-peak value, determining that the phase shift angle adjustment strategy is based on a summing operation of the phase shift angle control variable and the first phase shift angle; if the nth ripple voltage peak-to-peak value is greater than the n-1th ripple voltage peak-to-peak value, determining that the phase shift angle adjustment strategy is based on a difference operation of the phase shift angle control variable and the first phase shift angle.

[0091] It can be seen that in this embodiment, through the closed-loop logic of "preliminary adjustment → real-time compensation → strategy adjustment → final determination", combined with the feedback of the n-1th and nth ripple voltage peak-to-peak values, the optimal phase shift angle in each cycle is dynamically determined to ensure that the ripple voltage peak-to-peak value is minimized and stable under the current operating conditions, while improving the dynamic response speed and robustness of the system.

[0092] S240, determining a target phase shift angle based on the second phase shift angle and the multiple frequency jittering-related frequency values, wherein the target phase shift angle is a phase shift angle used for phase shift angle compensation; and when the flow reaches the (n+1)th frequency jittering cycle, performing a phase shift angle compensation operation based on the target phase shift angle to reduce the offset degree of the output voltage ripple.

[0093] Among them, the multiple frequency jittering related frequency values ​​may include the upper limit of the frequency jittering frequency and the lower limit of the frequency jittering frequency. When the power is transmitted in the forward direction, the transmission power of the dual active bridge system increases with the increase of the phase shift angle of the original secondary side square wave voltage. Therefore, at the frequency jittering frequency When the compensation value is negative; the jitter frequency When , the compensation value is positive. The upper limit of the jitter frequency is , the lower limit of the jitter frequency is The maximum compensation value of the phase shift angle is , in the nth frequency jitter cycle , the switching frequency changes from Change to In the process of , that is, the target phase shift angle is from the second phase shift angle Linear change to negative second phase shift angle .

[0094] If multiple frequency values ​​associated with frequency jittering are known parameters, then determining the second phase shift angle can determine the target phase shift angle. The corresponding second phase shift angle and the target phase shift angle are determined in each frequency cycle, thereby reducing the degree of output voltage ripple deviation during operation.

[0095] In a possible embodiment, the multiple frequency-jittering-related frequency values ​​include at least one of a switching frequency, a frequency-jittering frequency, a frequency-jittering frequency upper limit, and a frequency-jittering frequency lower limit. The switching frequency is a dynamically changing quantity, and the frequency-jittering frequency, the frequency-jittering frequency upper limit, and the frequency-jittering frequency lower limit are static quantities. Determining the target phase shift angle based on the second phase shift angle and the multiple frequency-jittering-related frequency values ​​includes: determining a proportional coefficient based on the second phase shift angle, the frequency-jittering frequency upper limit, the frequency-jittering frequency lower limit, and a proportional coefficient formula, wherein the proportional coefficient formula includes: ,in, is the proportionality coefficient, is the second phase shift angle, is the upper limit of the frequency jittering, is the lower limit of the frequency jittering frequency; and the target phase shift angle is determined based on the proportional coefficient, the switching frequency, the frequency jittering frequency, and a target phase shift angle formula, wherein the target phase shift angle formula includes: , where f is the switching frequency, is the frequency jittering frequency.

[0096] Among them, the switching frequency is a predictable quantity, and the second phase shift angle is the quantity calculated in the above embodiment. Based on this, the value of the target phase shift angle can be determined. .

[0097] The switching frequency f is the switching frequency of the power switch tube in the dual active bridge (DAB), which is a dynamic variable (changing with working conditions or control requirements). The jitter frequency used to modulate the switching frequency is a static value (fixed value), and the upper limit of the jitter frequency The maximum value allowed for the jitter frequency is a static value. The minimum value allowed for the frequency jitter is a static value. The proportional coefficient F relates the phase shift angle change to the frequency jitter range and is used for the linear mapping of the subsequent switching frequency. The deviation is linearly mapped to the target phase shift angle through the proportional coefficient F .

[0098] Specifically, the formula can also be written as:

[0099] ;

[0100] For examples, see Figure 4 , Figure 4 This is a flow chart of another method for controlling the output voltage ripple of a dual active bridge provided in an embodiment of the present application. Figure 4 The specific implementation of the control method of the present invention is based on the digital control chip of the dual active bridge power module and is implemented through the following detailed control process:

[0101] S401, the dual active bridge topology power supply is started, and the control process begins.

[0102] S402 , initializing relevant control variables, sampling the output voltage in real time, and calculating the peak-to-peak value of the ripple voltage in each frequency jittering cycle.

[0103] S403, calculating the phase shift angle control variable according to the output voltage ripple in real time.

[0104] Among them, the phase shift angle control variable D cycle =k×V pp ;in The dimension is The constant of D cycle Limit the amplitude to ensure that the dynamic response speed and steady-state ripple meet the design requirements. calculate , and output the results in real time in the loop Compensation is performed on the phase shift angle to obtain .

[0105] S404, adding a phase shift angle control variable.

[0106] Among them, increasing the phase shift angle is to increase it on the basis of the current phase shift angle, that is, if the current , then in On the basis of increasing the phase shift angle control variable, we can get .

[0107] S405 , comparing peak-to-peak values ​​of voltage ripples within a frequency jittering cycle before and after increasing the phase shift angle control variable.

[0108] Here, the peak-to-peak value of the voltage ripple is compared between the nth frequency jittering cycle and the n-1th frequency jittering cycle.

[0109] Among them, if the peak-to-peak value of the voltage ripple in the nth frequency jittering cycle is less than the peak-to-peak value of the voltage ripple in the n-1th frequency jittering cycle, that is, V pp(n) <V pp(n-1) , then repeat S404. If the peak-to-peak value of the voltage ripple in the nth frequency jittering cycle is greater than the peak-to-peak value of the voltage ripple in the n-1th frequency jittering cycle, that is, V pp(n) >V pp(n-1) , then execute S406.

[0110] S406, reducing the phase shift angle control variable.

[0111] S407 , comparing peak-to-peak values ​​of the voltage ripple within a frequency jittering cycle before and after reducing the phase shift angle control variable.

[0112] Among them, if the peak-to-peak value of the voltage ripple in the nth frequency jittering cycle is less than the peak-to-peak value of the voltage ripple in the n-1th frequency jittering cycle, that is, V pp(n) <V pp(n-1) , then repeat item S406. If the peak-to-peak value of the voltage ripple in the nth frequency jittering cycle is greater than the peak-to-peak value of the voltage ripple in the n-1th frequency jittering cycle, that is, V pp(n) >V pp(n-1) , then execute item S408.

[0113] S408, adding a phase shift angle control variable.

[0114] S409: Obtain the optimal third phase shift angle under the current working condition, so that the peak-to-peak value of the output ripple gradually approaches the minimum.

[0115] S410, detecting whether the working condition has changed.

[0116] If a change in the operating condition is detected, then S404 is executed. If no change in the operating condition is detected, then S411 is executed.

[0117] S411, the process ends.

[0118] It can be seen that in this embodiment, this step associates the second phase shift angle with the frequency jittering range through a proportional coefficient, and then linearly maps the target phase shift angle based on the deviation between the current switching frequency and the frequency jittering frequency. This design realizes the dynamic adjustment of the phase shift angle, ensuring that the ripple voltage remains stable when the switching frequency changes, while improving the robustness and response speed of the system. Furthermore, when the phase shift angle reverse compensation operation is performed based on the peak-to-peak value of the ripple voltage to offset the power transmission error caused by the frequency offset, the output power imbalance problem at the moment of frequency change is greatly alleviated, and the deterioration of the output voltage ripple is reduced.

[0119] In one possible embodiment, when the flow turns to the n+1 frequency jittering cycle, the output voltage ripple control method of the dual active bridge includes: obtaining a plurality of first circuit parameters and the nth ripple voltage peak-to-peak value under the current working condition, the nth ripple voltage peak-to-peak value is the difference between the peak value and the valley value of the ripple voltage in the nth frequency jittering cycle, the plurality of first circuit parameters include a plurality of frequency jittering related frequency values ​​and a fourth phase shift angle, that is, the above-mentioned target phase shift angle, which is described as the first target phase shift angle at this time; determining the phase shift angle control variable based on the nth ripple voltage peak-to-peak value; determining the phase shift angle control variable based on the phase shift angle control variable, the nth ripple voltage peak-to-peak value, the n+1th A fifth phase shift angle is determined based on the peak-to-peak value of the ripple voltage and the fourth phase shift angle, where the fifth phase shift angle is the optimal compensation phase shift angle within the n+2th frequency jittering cycle under the current operating condition, and the n+1th ripple voltage peak-to-peak value is the difference between the peak value and the valley value of the ripple voltage within the n+1th frequency jittering cycle. A second target phase shift angle is determined based on the fifth phase shift angle and the multiple frequency jittering-related frequency values, where the second target phase shift angle is the phase shift angle used for phase shift angle compensation. In addition, when the flow reaches the n+2th frequency jittering cycle, a phase shift angle compensation operation is performed based on the target phase shift angle to reduce the offset degree of the output voltage ripple.

[0120] It can be seen that in this embodiment, the controller obtains multiple first circuit parameters and the n-1th ripple voltage peak-to-peak value under the current working condition, the n-1th ripple voltage peak-to-peak value is the difference between the peak value and the valley value of the ripple voltage in the n-1th frequency jittering period, the multiple first circuit parameters include multiple frequency jittering related frequency values ​​and a first phase shift angle, the first phase shift angle is the maximum compensation phase shift angle in the n-1th frequency jittering period, where n is an integer greater than or equal to 2; based on the n-1th ripple voltage peak-to-peak value, the phase shift angle control variable is determined; based on the phase shift angle control variable, the n-1th ripple voltage peak-to-peak value , determining a second phase shift angle based on the nth ripple voltage peak-to-peak value and the first phase shift angle, the second phase shift angle being the optimal compensation phase shift angle within the nth frequency jittering cycle under the current operating condition, the nth ripple voltage peak-to-peak value being the difference between the peak and valley values ​​of the ripple voltage within the nth frequency jittering cycle; determining a target phase shift angle based on the second phase shift angle and the multiple frequency jittering-related frequency values, the target phase shift angle being the phase shift angle used for phase shift angle compensation; and, when the n+1th frequency jittering cycle is reached, performing a phase shift angle compensation operation based on the target phase shift angle to reduce the degree of output voltage ripple offset. In this way, when performing a phase shift angle reverse compensation operation based on the ripple voltage peak-to-peak value to offset the power transmission error caused by frequency offset, the output power imbalance problem at the moment of frequency change is greatly alleviated, and the deterioration of the output voltage ripple is reduced.

[0121] See Figure 5 , Figure 51 is a schematic structural diagram of an output voltage ripple control device for a dual active bridge proposed in an embodiment of the present application. The device is applied to a controller of a dual active bridge system. The output voltage ripple control device 500 for the dual active bridge includes: an acquisition module 510, a first determination module 520, a second determination module 530, and a third determination module 540, wherein:

[0122] An acquisition module 510 is configured to acquire a plurality of first circuit parameters and an (n-1)th peak-to-peak value of a ripple voltage under a current operating condition, where the (n-1)th peak-to-peak value of the ripple voltage is the difference between a peak value and a valley value of the ripple voltage in an (n-1)th frequency jittering cycle. The plurality of first circuit parameters include a plurality of frequency jittering-related frequency values ​​and a first phase shift angle, where the first phase shift angle is the maximum compensated phase shift angle in the (n-1)th frequency jittering cycle, where n is an integer greater than or equal to 2.

[0123] A first determining module 520 is configured to determine a phase shift angle control variable based on the (n-1)th ripple voltage peak-to-peak value;

[0124] a second determination module 530, configured to determine a second phase shift angle based on the phase shift angle control variable, the (n-1)th ripple voltage peak-to-peak value, the (n)th ripple voltage peak-to-peak value, and the first phase shift angle, where the second phase shift angle is the optimal compensation phase shift angle within the (n)th frequency jittering cycle under the current operating condition, and the (n)th ripple voltage peak-to-peak value is the difference between the peak value and the valley value of the ripple voltage within the (n)th frequency jittering cycle;

[0125] A third determination module 540 is configured to determine a target phase shift angle based on the second phase shift angle and the multiple frequency jittering-related frequency values, where the target phase shift angle is a phase shift angle used for phase shift angle compensation; and, when the frequency jittering cycle reaches the (n+1)th frequency jittering cycle, perform a phase shift angle compensation operation based on the target phase shift angle to reduce the offset degree of the output voltage ripple.

[0126] In a possible embodiment, the second determination module 530 is specifically configured to determine the second phase shift angle based on the phase shift angle control variable, the (n-1)th ripple voltage peak-to-peak value, the nth ripple voltage peak-to-peak value, and the first phase shift angle:

[0127] determining a third phase shift angle based on the first phase shift angle and the phase shift angle control variable;

[0128] Performing a compensation operation based on the third phase shift angle to obtain an nth ripple voltage peak-to-peak value generated based on the third phase shift angle compensation;

[0129] determining a phase shift angle adjustment strategy based on the nth ripple voltage peak-to-peak value and the n-1th ripple voltage peak-to-peak value, wherein the phase shift angle adjustment strategy is used to adjust the first phase shift angle based on the phase shift angle control variable;

[0130] The second phase shift angle is determined based on the phase shift angle adjustment strategy and the first phase shift angle.

[0131] In a possible embodiment, the second determining module 530 is specifically configured to:

[0132] If the nth ripple voltage peak-to-peak value is less than the n-1th ripple voltage peak-to-peak value, determining that the phase shift angle adjustment strategy is to perform a summation operation based on the phase shift angle control variable and the first phase shift angle;

[0133] If the peak-to-peak value of the nth ripple voltage is greater than the peak-to-peak value of the (n-1)th ripple voltage, it is determined that the phase shift angle adjustment strategy is to perform a difference operation based on the phase shift angle control variable and the first phase shift angle.

[0134] In a possible embodiment, the first determining module 520 is further configured to:

[0135] Acquiring a plurality of second circuit parameters under a current working condition, wherein the second circuit parameters include performance parameters of the dual active bridge system, wherein the performance parameters include response speed parameters and / or stability parameters;

[0136] determining a phase shift angle control parameter based on the second circuit parameter, wherein the phase shift angle control parameter is associated with the plurality of second circuit parameters of the dual active bridge system;

[0137] The phase shift angle control variable is determined based on the phase shift angle control parameter and the (n-1)th ripple voltage peak-to-peak value.

[0138] In a possible embodiment, the first determining module 520, in determining the phase shift angle control parameter based on the second circuit parameter, is specifically configured to:

[0139] Determining a transfer function based on a preset small signal model and circuit information parameters, wherein the transfer function is used to reflect the dynamic impact of a duty cycle disturbance on the output voltage, wherein the duty cycle disturbance is a disturbance generated by regulating the first phase shift angle based on the phase shift angle control variable;

[0140] The phase shift angle control parameter is determined based on the transfer function, the control parameter control calculation model and the second circuit parameter. The control parameter calculation model is used to constrain the association between the phase shift angle control parameter and the multiple second circuit parameters and the control parameter boundary threshold. The control parameter boundary threshold is used to constrain the maximum and minimum values ​​of the phase shift angle control parameter.

[0141] In a possible embodiment, the first determining module 520, in determining the phase shift angle control variable based on the (n-1)th ripple voltage peak-to-peak value, is further configured to:

[0142] determining a first simulation result based on the phase shift angle control parameter and a preset simulation control model, wherein the first simulation result is used to characterize a change trend of an nth peak-to-peak value of the simulated ripple voltage of the dual active bridge system when the phase shift angle control parameter is adopted, and the preset simulation control model is a model for simulating the dual active bridge system;

[0143] determining an nth simulation response rate parameter based on the first simulation result, the nth simulation response rate parameter being used to characterize a response speed of the nth ripple voltage peak-to-peak value simulation value within a preset time length, where the preset time length is a preset expected response time length;

[0144] If the nth simulation response rate parameter is not within the preset response rate threshold range, fine-tuning is performed based on the phase shift angle control variable; if the nth simulation response rate parameter is within the preset response rate threshold range, the phase shift angle control variable is determined.

[0145] In a possible embodiment, the multiple frequency jittering-related frequency values ​​include at least one of a switching frequency, a frequency jittering frequency, a frequency jittering frequency upper limit, and a frequency jittering frequency lower limit. The switching frequency is a dynamically changing quantity, and the frequency jittering frequency, the frequency jittering frequency upper limit, and the frequency jittering frequency lower limit are static quantities. The third determination module 540 is specifically configured to determine the target phase shift angle based on the second phase shift angle and the multiple frequency jittering-related frequency values:

[0146] The proportional coefficient is determined based on the second phase shift angle, the upper limit of the frequency jittering frequency, the lower limit of the frequency jittering frequency, and a proportional coefficient formula, wherein the proportional coefficient formula includes: ,in, is the proportionality coefficient, is the second phase shift angle, is the upper limit of the frequency jittering, is the lower limit of the frequency jittering;

[0147] The target phase shift angle is determined based on the proportional coefficient, the switching frequency, the frequency jittering frequency, and a target phase shift angle formula, wherein the target phase shift angle formula includes: , where f is the switching frequency, is the frequency jittering frequency.

[0148] It can be seen that in this embodiment, the device obtains multiple first circuit parameters and the n-1th ripple voltage peak-to-peak value under the current working condition through the controller, the n-1th ripple voltage peak-to-peak value is the difference between the peak value and the valley value of the ripple voltage in the n-1th frequency jittering period, the multiple first circuit parameters include multiple frequency jittering related frequency values ​​and a first phase shift angle, the first phase shift angle is the maximum compensation phase shift angle in the n-1th frequency jittering period, where n is an integer greater than or equal to 2; the phase shift angle control variable is determined based on the n-1th ripple voltage peak-to-peak value; based on the phase shift angle control variable, the n-1th ripple voltage A second phase shift angle is determined based on the peak-to-peak value, the nth ripple voltage peak-to-peak value, and the first phase shift angle. The second phase shift angle is the optimal compensation phase shift angle within the nth frequency jittering cycle under the current operating condition. The nth ripple voltage peak-to-peak value is the difference between the peak and valley values ​​of the ripple voltage within the nth frequency jittering cycle. A target phase shift angle is determined based on the second phase shift angle and the multiple frequency jittering-related frequency values. The target phase shift angle is the phase shift angle used for phase shift angle compensation. When the frequency jittering cycle reaches the (n+1)th frequency jittering cycle, a phase shift angle compensation operation is performed based on the target phase shift angle to reduce the degree of output voltage ripple offset. In this way, when a phase shift angle reverse compensation operation is performed based on the peak-to-peak value of the ripple voltage to offset the power transmission error caused by frequency offset, the output power imbalance problem at the moment of frequency change is greatly alleviated, and the deterioration of the output voltage ripple is reduced.

[0149] It is worth noting that the specific functional implementation of the output voltage ripple control device 500 of the dual active bridge can be found in the above Figure 2 In the description of the dual active bridge output voltage ripple control method shown in FIG. , for example, the acquisition module 510 is used to implement the relevant contents of step S210, the first determination module 520 is used to implement the relevant contents of step S220, the second determination module 530 is used to implement the relevant contents of step S230, and the third determination module 540 is used to implement the relevant contents of step S240. The various units or modules in the dual active bridge output voltage ripple control device 500 can be individually or entirely combined into one or more additional units or modules, or one or more of the units or modules can be further divided into multiple functionally smaller units or modules to achieve the same operation without affecting the technical effects of the embodiments of the present invention. The aforementioned units or modules are divided based on logical functions. In actual applications, the functions of one unit (or module) are implemented by multiple units (or modules), or the functions of multiple units (or modules) are implemented by one unit (or module).

[0150] In the case of integrated units, see Figure 6 , Figure 6 FIG. 1 is a schematic structural diagram of another output voltage ripple control device of a dual active bridge provided in an embodiment of the present application. Figure 6As shown, the output voltage ripple control device 500 of the dual active bridge includes: a processing module 502 and a communication module 501. The processing module 502 is used to control and manage the actions of the output voltage ripple control device 500 of the dual active bridge, for example, executing the steps of the acquisition module 510, the first determination module 520, the second determination module 530 and the third determination module 540, and / or other processes for performing the technology described herein. The communication module 501 is used for interaction between the output voltage ripple control device 500 of the dual active bridge and other devices. Figure 6 As shown, the output voltage ripple control device 500 of the dual active bridge may further include a storage module 503 , and the storage module 503 is used to store program codes and data of the output voltage ripple control device 500 of the dual active bridge.

[0151] The processing module 502 may be a processor or controller, such as a central processing unit (CPU), a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. It may implement or execute the various exemplary logic blocks, modules, and circuits described in conjunction with the disclosure of this application. The processor may also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of a DSP and a microprocessor, and the like. The communication module 501 may be a transceiver, an RF circuit, or a communication interface, and the like. The storage module 503 may be a memory.

[0152] Among them, all relevant contents of each scenario involved in the above method embodiment can be referred to the functional description of the corresponding functional module, and will not be repeated here. The output voltage ripple control device 500 of the dual active bridge can execute the above Figure 2 The output voltage ripple control method of the dual active bridge is shown.

[0153] See also Figure 7 , Figure 7 This is a schematic diagram of the structure of an electronic device proposed in an embodiment of the present application. Figure 7 As shown, the electronic device 700 includes a processor 710 , a memory 720 , a communication interface 730 and one or more programs 721 . The one or more programs 721 are stored in the memory 720 and are configured to be executed by the processor 710 .

[0154] The processor 710, the memory 720, and the communication interface 730 are interconnected and perform communication between them.

[0155] The memory 720 can be a volatile memory such as a dynamic random access memory DRAM, or a non-volatile memory such as a mechanical hard disk. The memory 720 is used to store a set of executable program codes, and the processor 710 is used to call one or more programs 721 stored in the memory 720, and can execute the above-mentioned Figure 2-Figure 4 Part or all of the steps of any dual active bridge output voltage ripple control method described in the embodiments.

[0156] Among them, the electronic device 700 may include smart phones (such as Android phones, iOS phones, Windows Phone phones, etc.), tablet computers, PDAs, driving recorders, vehicle-mounted electronic devices, servers, laptops, mobile Internet electronic devices (MID, Mobile Internet Devices) or wearable electronic devices (such as smart watches, Bluetooth headsets), etc. The above are only examples and not exhaustive, including but not limited to the above electronic devices.

[0157] It can be seen that the electronic device 700 obtains multiple first circuit parameters and the n-1th ripple voltage peak-to-peak value under the current working condition, the n-1th ripple voltage peak-to-peak value is the difference between the peak value and the valley value of the ripple voltage in the n-1th frequency jittering period, the multiple first circuit parameters include multiple frequency jittering related frequency values ​​and a first phase shift angle, the first phase shift angle is the maximum compensation phase shift angle in the n-1th frequency jittering period, where n is an integer greater than or equal to 2; based on the n-1th ripple voltage peak-to-peak value, the phase shift angle control variable is determined; based on the phase shift angle control variable, the n-1th ripple voltage peak-to-peak value, the phase shift angle control variable is determined. The second phase shift angle is determined based on the value, the nth ripple voltage peak-to-peak value, and the first phase shift angle. The second phase shift angle is the optimal compensation phase shift angle within the nth frequency jittering cycle under the current operating condition. The nth ripple voltage peak-to-peak value is the difference between the peak and valley values ​​of the ripple voltage within the nth frequency jittering cycle. A target phase shift angle is determined based on the second phase shift angle and the multiple frequency jittering-related frequency values. The target phase shift angle is the phase shift angle used for phase shift angle compensation. When the frequency reaches the (n+1)th frequency jittering cycle, a phase shift angle compensation operation is performed based on the target phase shift angle to reduce the degree of output voltage ripple offset. In this way, when a phase shift angle reverse compensation operation is performed based on the peak-to-peak value of the ripple voltage to offset the power transmission error caused by frequency offset, the output power imbalance problem at the moment of frequency change is greatly alleviated, and the deterioration of the output voltage ripple is reduced.

[0158] An embodiment of the present application also provides a computer storage medium, wherein the computer storage medium stores a computer program for electronic data exchange, and the computer program enables a computer to execute part or all of the steps of any method described in the above method embodiments, and the above computer includes an electronic device.

[0159] The present application also provides a computer program product comprising a non-transitory computer-readable storage medium storing a computer program, wherein the computer program is operable to cause a computer to perform some or all of the steps of any of the methods described in the above method embodiments. The computer program product may be a software installation package, and the computer may comprise an electronic device.

[0160] It should be noted that for the aforementioned method embodiments, for the sake of simplicity, they are all expressed as a series of action combinations, but those skilled in the art should be aware that this application is not limited by the order of the actions described, because according to this application, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by this application.

[0161] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0162] In the several embodiments provided in this application, it should be understood that the disclosed devices can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the above-mentioned units is only a logical function division. In actual implementation, there may be other division methods, such as 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, and the indirect coupling or communication connection of devices or units can be electrical or other forms.

[0163] The units described above as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0164] In addition, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0165] If the above-mentioned 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 memory. Based on this understanding, the technical solution of the present application, or the part that contributes to the existing technology, or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a memory and includes a number of instructions for enabling a computer electronic device (which can be a personal computer, electronic device, or network electronic device, etc.) to execute all or part of the steps of the above-mentioned methods in each embodiment of the present application. The aforementioned memory 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, etc. Various media that can store program code.

[0166] Those skilled in the art will appreciate that all or part of the steps in the various methods of the above embodiments can be completed by a program instructing related hardware. The program can be stored in a computer-readable memory, which may include a flash drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0167] The above is a detailed introduction to the embodiments of the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and core idea of ​​the present application. At the same time, for those skilled in the art, according to the idea of ​​the present application, there may be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A method for controlling output voltage ripple of a dual active bridge, characterized in that: Controller for dual active bridge systems, including: Obtaining multiple first circuit parameters and an (n-1)th ripple voltage peak-to-peak value under a current operating condition, where the (n-1)th ripple voltage peak-to-peak value is the difference between a peak value and a valley value of the ripple voltage in an (n-1)th frequency jittering cycle. The multiple first circuit parameters include multiple frequency jittering-related frequency values ​​and a first phase shift angle, where the first phase shift angle is a maximum compensated phase shift angle in the (n-1)th frequency jittering cycle, where n is an integer greater than or equal to 2. Determining a phase shift angle control variable based on the (n-1)th ripple voltage peak-to-peak value; determining a second phase shift angle based on the phase shift angle control variable, the (n-1)th ripple voltage peak-to-peak value, the (n)th ripple voltage peak-to-peak value, and the first phase shift angle, where the second phase shift angle is the optimal compensation phase shift angle within the (n)th frequency jittering cycle under the current operating condition, and the (n)th ripple voltage peak-to-peak value is the difference between the peak value and the valley value of the ripple voltage within the (n)th frequency jittering cycle; A target phase shift angle is determined based on the second phase shift angle and the multiple frequency jittering-related frequency values, where the target phase shift angle is used to perform phase shift angle compensation. When the frequency jittering cycle reaches the (n+1)th frequency jittering period, a phase shift angle compensation operation is performed based on the target phase shift angle to reduce the offset degree of the output voltage ripple.

2. The method according to claim 1, characterized in that The determining of the second phase shift angle based on the phase shift angle control variable, the (n-1)th ripple voltage peak-to-peak value, the (n)th ripple voltage peak-to-peak value, and the first phase shift angle includes: determining a third phase shift angle based on the first phase shift angle and the phase shift angle control variable; Performing a compensation operation based on the third phase shift angle to obtain an nth ripple voltage peak-to-peak value generated based on the third phase shift angle compensation; determining a phase shift angle adjustment strategy based on the nth ripple voltage peak-to-peak value and the n-1th ripple voltage peak-to-peak value, wherein the phase shift angle adjustment strategy is used to adjust the first phase shift angle based on the phase shift angle control variable; The second phase shift angle is determined based on the phase shift angle adjustment strategy and the first phase shift angle.

3. The method according to claim 2, characterized in that The determining of the phase shift angle adjustment strategy based on the nth ripple voltage peak-to-peak value and the n-1th ripple voltage peak-to-peak value includes: If the nth ripple voltage peak-to-peak value is less than the n-1th ripple voltage peak-to-peak value, determining that the phase shift angle adjustment strategy is to perform a summation operation based on the phase shift angle control variable and the first phase shift angle; If the peak-to-peak value of the nth ripple voltage is greater than the peak-to-peak value of the (n-1)th ripple voltage, it is determined that the phase shift angle adjustment strategy is to perform a difference operation based on the phase shift angle control variable and the first phase shift angle.

4. The method according to claim 1, wherein The determining of the phase shift angle control variable based on the (n-1)th ripple voltage peak-to-peak value includes: Acquiring a plurality of second circuit parameters under a current working condition, wherein the second circuit parameters include performance parameters of the dual active bridge system, wherein the performance parameters include response speed parameters and / or stability parameters; determining a phase shift angle control parameter based on the second circuit parameter, wherein the phase shift angle control parameter is associated with the plurality of second circuit parameters of the dual active bridge system; The phase shift angle control variable is determined based on the phase shift angle control parameter and the (n-1)th ripple voltage peak-to-peak value.

5. The method according to claim 4, characterized in that Determining the phase shift angle control parameter based on the second circuit parameter includes: Determining a transfer function based on a preset small signal model and circuit information parameters, wherein the transfer function is used to reflect the dynamic impact of a duty cycle disturbance on the output voltage, wherein the duty cycle disturbance is a disturbance generated by regulating the first phase shift angle based on the phase shift angle control variable; The phase shift angle control parameter is determined based on the transfer function, the control parameter control calculation model and the second circuit parameter. The control parameter calculation model is used to constrain the association between the phase shift angle control parameter and the multiple second circuit parameters and the control parameter boundary threshold. The control parameter boundary threshold is used to constrain the maximum and minimum values ​​of the phase shift angle control parameter.

6. The method according to claim 4 or 5, characterized in that The determining of the phase shift angle control variable based on the (n-1)th ripple voltage peak-to-peak value further includes: determining a first simulation result based on the phase shift angle control parameter and a preset simulation control model, wherein the first simulation result is used to characterize a change trend of an nth peak-to-peak value of the simulated ripple voltage of the dual active bridge system when the phase shift angle control parameter is adopted, and the preset simulation control model is a model for simulating the dual active bridge system; determining an nth simulation response rate parameter based on the first simulation result, the nth simulation response rate parameter being used to characterize a response speed of the nth ripple voltage peak-to-peak value simulation value within a preset time length, where the preset time length is a preset expected response time length; If the nth simulation response rate parameter is not within the preset response rate threshold range, fine-tuning is performed based on the phase shift angle control variable; if the nth simulation response rate parameter is within the preset response rate threshold range, the phase shift angle control variable is determined.

7. The method according to claim 1, characterized in that The multiple frequency jittering-related frequency values ​​include at least one of a switching frequency, a frequency jittering frequency, a frequency jittering frequency upper limit, and a frequency jittering frequency lower limit. The switching frequency is a dynamically changing quantity, and the frequency jittering frequency, the frequency jittering frequency upper limit, and the frequency jittering frequency lower limit are static quantities. Determining the target phase shift angle based on the second phase shift angle and the multiple frequency jittering-related frequency values ​​includes: The proportional coefficient is determined based on the second phase shift angle, the upper limit of the frequency jittering frequency, the lower limit of the frequency jittering frequency, and a proportional coefficient formula, wherein the proportional coefficient formula includes: ,in, is the proportionality coefficient, is the second phase shift angle, is the upper limit of the frequency jittering, is the lower limit of the frequency jittering; The target phase shift angle is determined based on the proportional coefficient, the switching frequency, the frequency jittering frequency, and a target phase shift angle formula, wherein the target phase shift angle formula includes: , where f is the switching frequency, is the frequency jittering frequency.

8. An output voltage ripple control device for a dual active bridge, characterized in that: A controller for a dual active bridge system, the device comprising: an acquisition module, configured to acquire a plurality of first circuit parameters and an (n-1)th ripple voltage peak-to-peak value under a current operating condition, where the (n-1)th ripple voltage peak-to-peak value is the difference between a peak value and a valley value of the ripple voltage in an (n-1)th frequency jittering cycle; the plurality of first circuit parameters include a plurality of frequency jittering-related frequency values ​​and a first phase shift angle, where the first phase shift angle is a maximum compensated phase shift angle in an (n-1)th frequency jittering cycle, where n is an integer greater than or equal to 2; A first determining module is configured to determine a phase shift angle control variable based on the (n-1)th ripple voltage peak-to-peak value; a second determination module, configured to determine a second phase shift angle based on the phase shift angle control variable, the (n-1)th ripple voltage peak-to-peak value, the (n)th ripple voltage peak-to-peak value, and the first phase shift angle, wherein the second phase shift angle is the optimal compensation phase shift angle within the (n)th frequency jittering cycle under the current operating condition, and the (n)th ripple voltage peak-to-peak value is the difference between the peak value and the valley value of the ripple voltage within the (n)th frequency jittering cycle; a third determination module, configured to determine a target phase shift angle based on the second phase shift angle and the multiple frequency jittering-related frequency values, where the target phase shift angle is a phase shift angle used for phase shift angle compensation; and, when the frequency jittering cycle reaches the (n+1)th frequency jittering cycle, perform a phase shift angle compensation operation based on the target phase shift angle to reduce the offset degree of the output voltage ripple.

9. A computer-readable storage medium, characterized in that An output voltage ripple control program of a dual active bridge is stored, wherein the output voltage ripple control program of the dual active bridge includes execution instructions. When the execution instructions are executed by a processor, the processor executes the method according to any one of claims 1 to 7.

10. An electronic device, characterized in that: comprising a processor, a memory, a communication interface, and one or more programs stored in the memory and configured to be executed by the processor; When the processor executes the one or more programs, the processor performs the method according to any one of claims 1 to 7.

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