A method and device for determining resonance parameters of a resonant converter

Abstract

The present invention discloses a method and device for determining the resonant parameters of a resonant converter, wherein the method includes: establishing a voltage parameter set and a resonant parameter set, wherein the voltage parameter set includes multiple voltage groups; traversing the voltage groups in the voltage parameter set and the resonant parameter groups in the resonant parameter set to calculate a steady-state operating frequency set of the resonant converter; using each steady-state operating frequency and its corresponding voltage group and equivalent resonant parameter group to calculate the corresponding steady-state resonant current peak value of the resonant converter at the steady-state operating frequency; obtaining a calculation parameter group corresponding to the steady-state operating frequency set when the steady-state operating frequency meets a first preset condition and the corresponding steady-state resonant current peak value meets a second preset condition, to obtain multiple calculation parameter groups; and selecting an optimal equivalent resonant parameter group from the multiple calculation parameter groups. In the present invention, the determined optimal equivalent resonant parameter group can achieve precise control of the resonant cavity current under different input and output voltages.

Description

Technical Field

[0001] The present invention relates to the technical field of resonant converters, and in particular to a method and device for determining resonant parameters of a resonant converter. Background Art

[0002] In recent years, high-voltage DC power supplies have been widely used in medical X-ray machines, industrial electrostatic precipitators, and wastewater and organic matter treatment devices. However, the LCC resonant converter, a common topology for these devices, suffers from a mismatch between the actual and theoretical parameters of the LCC resonant cavity due to the influence of the actual operating environment and the parasitic parameters introduced by the high number of turns in the boost transformer. This results in a significant difference between the actual and theoretical operating frequencies in the LCC resonant converter's operation.

[0003] Under the traditional PI control scheme, the inconsistency between the actual resonant parameters and the theoretical resonant parameters can be compensated for by PI control on the operating frequency of the LCC converter to achieve ideal working effect; however, under the control of the newly proposed state trajectory algorithm of the LCC converter, the mismatch between the actual resonant parameters and the theoretical resonant parameters will lead to the inability to accurately control the resonant cavity current, resulting in overshoot or too small resonant current, affecting the control effect of the state trajectory algorithm. Summary of the Invention

[0004] Therefore, the present invention aims to solve the technical problem in the prior art that actual resonance parameters do not match theoretical resonance parameters, thereby providing a method and device for determining resonance parameters of a resonant converter.

[0005] According to a first aspect, an embodiment of the present invention provides a method for determining resonant parameters of a resonant converter, comprising the following steps:

[0006] Establishing a voltage parameter set and a resonance parameter set, wherein the voltage parameter set includes multiple voltage groups, each of which includes an input voltage of the resonant converter and a corresponding output voltage thereof; and the resonance parameter set includes multiple resonance parameter groups, each of which includes a corresponding set of inductors and capacitors in an equivalent circuit of the resonant converter;

[0007] Traversing the voltage groups in the voltage parameter set and the resonance parameter groups in the resonance parameter set, and calculating a steady-state operating frequency set of the resonant converter, wherein each steady-state operating frequency in the steady-state operating frequency set corresponds to a set of calculation parameter groups, and a set of the calculation parameter groups includes a set of voltage groups and a corresponding set of equivalent resonance parameter groups;

[0008] Calculating the peak value of the steady-state resonant current corresponding to the resonant converter at the steady-state operating frequency using each of the steady-state operating frequencies and the corresponding voltage group and equivalent resonant parameter group;

[0009] Obtaining a calculation parameter group corresponding to when the steady-state operating frequency in the steady-state operating frequency set satisfies a first preset condition and the corresponding steady-state resonant current peak satisfies a second preset condition, to obtain multiple calculation parameter groups;

[0010] An optimal equivalent resonance parameter group is selected from the multiple calculation parameter groups, wherein the optimal equivalent resonance parameter group is an equivalent resonance parameter group having the largest number of corresponding different voltage groups among the multiple calculation parameter groups.

[0011] Optionally, the obtaining of a calculation parameter group corresponding to when the steady-state operating frequency in the steady-state operating frequency set satisfies a first preset condition and the corresponding steady-state resonant current peak satisfies a second preset condition, to obtain multiple calculation parameter groups, includes:

[0012] Determining, group by group, whether the steady-state operating frequency corresponding to each calculation parameter group satisfies the first preset condition, and determining whether the corresponding steady-state resonant current peak value satisfies the second preset condition;

[0013] The calculation parameter groups corresponding to the steady-state operating frequency satisfying the first preset condition and the steady-state resonant current peak satisfying the second preset condition are recorded to obtain the multiple calculation parameter groups.

[0014] Optionally, the steady-state operating frequency is calculated using the following formula:

[0015]

[0016] Vo is the output voltage of the resonant converter, Vin is the input voltage of the resonant converter, n is the primary-to-secondary turns ratio of the transformer in the resonant converter, kin is the voltage proportional coefficient, sin(θ / 2) is the empirical coefficient, fn is the steady-state operating frequency of the resonant converter, Cn is the capacitance ratio of the resonant converter, and Q is the quality factor.

[0017] Optionally, the method of calculating the steady-state resonant current peak value corresponding to the resonant converter at the steady-state operating frequency using each of the steady-state operating frequencies and its corresponding voltage group and equivalent resonant parameter group includes: obtaining the resonant frequency in the resonant converter equivalent circuit; calculating the actual operating frequency of the resonant converter using the steady-state operating frequency and the resonant frequency; calculating the complex variable in the transfer function in the resonant converter equivalent circuit according to the actual operating frequency; and calculating the steady-state resonant current peak value according to the complex variable, voltage group and resonant parameter group.

[0018] Optionally, the steady-state resonant current peak value is calculated by the following formula:

[0019]

[0020] I Ls is the peak value of the steady-state resonant current, Ls is the corresponding inductance in the equivalent circuit of the resonant converter, C s 、C p 、C e are the corresponding capacitors in the equivalent circuit of the resonant converter, R e is the corresponding resistance in the equivalent circuit of the resonant converter, s is the complex variable in the transfer function in the equivalent circuit of the resonant converter, and π is a constant.

[0021] Optionally, the voltage proportional coefficient is a ratio of the fundamental input voltage of the resonant converter equivalent circuit to the input voltage of the resonant converter.

[0022] According to a second aspect, an embodiment of the present invention provides a device for determining a resonant parameter of a resonant converter, comprising:

[0023] a data module, configured to establish a voltage parameter set and a resonance parameter set, wherein the voltage parameter set includes multiple voltage groups, each of which includes an input voltage of the resonant converter and a corresponding output voltage thereof; and the resonance parameter set includes multiple resonance parameter groups, each of which includes a corresponding set of inductors and capacitors in an equivalent circuit of the resonant converter;

[0024] a frequency module, configured to traverse the voltage groups in the voltage parameter set and the resonance parameter groups in the resonance parameter set, and calculate a steady-state operating frequency set of the resonant converter, wherein each steady-state operating frequency in the steady-state operating frequency set corresponds to a set of calculation parameter groups, and a set of the calculation parameter groups includes a set of voltage groups and a corresponding set of equivalent resonance parameter groups;

[0025] A peak module, configured to calculate the steady-state resonant current peak value corresponding to the resonant converter at each steady-state operating frequency using its corresponding voltage group and equivalent resonant parameter group;

[0026] a condition module, configured to obtain a calculation parameter group corresponding to when the steady-state operating frequency in the steady-state operating frequency set satisfies a first preset condition and the corresponding steady-state resonant current peak satisfies a second preset condition, to obtain multiple calculation parameter groups;

[0027] A selection module is used to select an optimal equivalent resonance parameter group from the multiple calculation parameter groups, wherein the optimal equivalent resonance parameter group is the resonant equivalent resonance parameter group corresponding to the largest number of different voltage groups among the multiple calculation parameter groups.

[0028] Optionally, the selection module further includes:

[0029] a judgment module, configured to judge, group by group, whether the steady-state operating frequency corresponding to each calculation parameter group satisfies the first preset condition, and to judge whether the corresponding steady-state resonant current peak value satisfies the second preset condition;

[0030] The recording module is used to record the calculation parameter groups corresponding to the steady-state operating frequency meeting the first preset condition and the steady-state resonant current peak meeting the second preset condition, to obtain the multiple calculation parameter groups.

[0031] According to a third aspect, an embodiment of the present invention provides a computer device comprising: a memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the above-mentioned method for determining the resonant parameters of the resonant converter by executing the computer instructions.

[0032] According to a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores computer instructions, and the computer instructions are used to enable the computer to execute the above-mentioned method for determining the resonant parameters of the resonant converter.

[0033] The technical solution of the present invention has the following advantages:

[0034] In this embodiment, a voltage parameter set and a resonance parameter set are first established, and the voltage groups in the voltage parameter set and the resonance parameter groups in the resonance parameter set are traversed to calculate a steady-state operating frequency set of the resonant converter. The steady-state resonant current peak value corresponding to the resonant converter at the steady-state operating frequency is calculated using each steady-state operating frequency and its corresponding voltage group and equivalent resonance parameter group. Secondly, a calculation parameter group corresponding to the steady-state operating frequency set when the steady-state operating frequency satisfies a first preset condition and the corresponding steady-state resonant current peak value satisfies a second preset condition is obtained to obtain multiple calculation parameter groups. Finally, an optimal equivalent resonant parameter group is selected from the multiple calculation parameter groups, wherein the optimal equivalent resonant parameter group is the equivalent resonant parameter group with the largest number of corresponding different voltage groups in the multiple calculation parameter groups. By selecting the optimal equivalent resonant parameter group, it is achieved that under different input and output voltages, the steady-state operating frequency and the steady-state resonant current peak value during operation are within the required steady-state operating frequency and the required steady-state resonant current peak value range, and the resonant cavity current can be accurately controlled without causing the resonant current to overshoot or be too small, thereby affecting the control effect of the state trajectory algorithm. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0036] Figure 1 This is a flowchart of a specific example of a method for determining resonant parameters of a resonant converter in embodiment 1 of the present invention;

[0037] Figure 2 1 is a schematic structural diagram of a specific example of the topological structure of the LCC resonant converter in Example 1 of the present invention;

[0038] Figure 3 This is a structural diagram of a specific example of a fundamental wave equivalent diagram in Example 1 of the present invention;

[0039] Figure 4 This is a flowchart of a specific example of selecting the optimal equivalent resonance parameter group in embodiment 1 of the present invention;

[0040] Figure 5 This is a principle block diagram of a specific example of a device for determining resonant parameters of a resonant converter in embodiment 2 of the present invention;

[0041] Figure 6 This is a structural diagram of a specific example of a computer device in Example 3 of the present invention. DETAILED DESCRIPTION

[0042] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0043] In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0044] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; internal connections between two components; wireless connections or wired connections. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0045] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0046] Example 1

[0047] This embodiment provides a method for determining the resonant parameters of a resonant converter. The method can be executed by a server or other device. The method calculates the device parameters and voltage values ​​required for the operation of the resonant converter by inputting them into the server or other device, determines the calculation results, and screens the resonant parameters that meet the conditions after determination, thereby determining the resonant parameters of the resonant converter. Figure 1 As shown, the following steps are included:

[0048] Step S101, establishing a voltage parameter set and a resonance parameter set, wherein the voltage parameter set includes multiple voltage groups, each of which includes an input voltage of the resonant converter and its corresponding output voltage; the resonance parameter set includes multiple resonance parameter groups, each of which includes a corresponding set of inductors and capacitors in the resonant converter equivalent circuit.

[0049] In this embodiment, the LCC resonant converter topology is taken as an example. Figure 2 As shown, the LCC resonant converter topology consists of four switch tubes S1, S2, S3, and S4, and the resonant cavity is composed of a resonant inductor L r , series resonant capacitor C r and the parallel resonant capacitor C p The primary-to-secondary turns ratio of the transformer in the resonant converter is 1:n, and the secondary rectifier bridge includes four diodes, namely D5, D6, D7, and D8. The input voltage of the LCC resonant converter is V in , the output voltage of the LCC resonant converter is V o , the output uses capacitor C o Filtering is performed to provide a stable output voltage with small fluctuations. The capacitor C o Also with the output equivalent load R L in parallel.

[0050] To simplify the analysis, the fundamental wave equivalent method is used to equate the LCC resonant converter topology to an RC parallel circuit, which is the fundamental wave equivalent circuit, as shown in Figure 3 As shown. After Fourier transforming the transformer primary voltage and current, take its fundamental component as the fundamental input voltage V of the resonant converter equivalent circuit. AB1 And the fundamental output voltage V Cp1 , R e is the equivalent resistance, C e is the equivalent capacitance. L s 、C s 、C p are the equivalent series resonant inductor, equivalent series resonant capacitor and equivalent parallel resonant capacitor, respectively. p With the parallel resonant capacitor C p For the same resonant capacitor parameters, resonant inductor L r and the equivalent series resonant inductor L s For the same resonant inductor parameters, series resonant capacitor C r and the equivalent series resonant capacitor C s For the same resonant capacitor parameters.

[0051] In this embodiment, a voltage parameter set and a resonance parameter set are first established, wherein the voltage parameter set may include multiple voltage groups, and one voltage group includes: the input voltage V in And its corresponding output voltage V o The resonant parameter set may include multiple resonant parameter groups or only one resonant parameter group, wherein one resonant parameter group includes a corresponding set of inductors and capacitors in the resonant converter equivalent circuit, which may be the equivalent series resonant inductor L corresponding to the fundamental wave equivalent circuit of this embodiment. s , equivalent series resonant capacitor C s and the equivalent parallel resonant capacitor C p That is to say, in this embodiment, the equivalent series resonant inductor L s , equivalent series resonant capacitor C s and the equivalent parallel resonant capacitor C p It can be a set of resonance parameter groups.

[0052] It should be noted that in this embodiment, the elements in the established voltage parameter set and resonance parameter set are all parameters, that is, the input voltage of the resonant converter and its corresponding output voltage, equivalent series resonant inductance, equivalent series resonant capacitance, and equivalent parallel resonant capacitance are all parameter values, that is, specific numerical values. For example: there are three voltage groups, namely [a, a1], [b, b1], [c, c1], and two resonance parameter groups, namely [d1, d2, d3], [e1, e2, e3]. Then the voltage parameter set is {[a, a1], [b, b1], [c, c1]}, and the resonance parameter set is {[d1, d2, d3], [e1, e2, e3]}, where ac, a1-c1, d1-d3, and e1-e3 are all constants. Among them, the parameter value of the resonance parameter group can be the resonance parameter group corresponding to the actual steady-state operating frequency in actual work or the resonance parameter group commonly involved in actual work. The parameter value of the voltage group may also be the input or output voltage often involved in actual work.

[0053] Step S102, traverse the voltage groups in the voltage parameter set and the resonance parameter groups in the resonance parameter set, and calculate the steady-state operating frequency set of the resonant converter, wherein each steady-state operating frequency in the steady-state operating frequency set corresponds to a group of calculation parameter groups, and a group of the calculation parameter groups includes a group of voltage groups and a corresponding group of equivalent resonance parameter groups.

[0054] When calculating the steady-state operating frequency of a resonant converter, a binary iterative calculation method can be used to fit the steady-state operating frequency corresponding to the current input and output voltages and resonant parameter values. In this embodiment, taking a set of voltage groups and a set of resonant parameter groups as an example, a set of voltage groups in the voltage parameter set and a set of resonant parameter groups in the resonant parameter set are selected for calculation. Specifically, the binary method can be used to continuously change the parameter values ​​in the selected resonant parameter group so that the result calculated based on the parameter values ​​in the resonant parameter group infinitely approaches the ratio of the voltage groups. The specific formula will be described below. A ratio range can be set. That is, when the result calculated based on the parameter values ​​in the resonant parameter group meets the set ratio range, the steady-state operating frequency calculated based on the resonant parameter group after the binary method is determined to be the steady-state operating frequency corresponding to the voltage group and the resonant parameter group after the binary method is changed. In this embodiment, the resonant parameter group after the binary method is called an equivalent resonant parameter group. That is, the voltage group and the equivalent resonant parameter group are called a set of calculated parameter groups in this embodiment, and the steady-state operating frequency corresponds to a set of calculated parameter groups.

[0055] Furthermore, a set of voltage groups not involved in the calculation is continuously selected from the voltage parameter set, and a set of resonance parameter groups from the resonance parameter set. The selected set of resonance parameter groups can be the same set of resonance parameter groups as described above. Similarly, a binary iterative calculation method is used to fit the steady-state operating frequency corresponding to the current input and output voltages and resonance parameter values, and ultimately the steady-state operating frequency set of the resonant converter is calculated. Each steady-state operating frequency in the steady-state operating frequency set corresponds to a set of calculation parameter groups, that is, a set of voltage groups and a set of equivalent resonance parameter groups.

[0056] Taking the above example, the voltage parameter set is {[a, a1], [b, b1], [c, c1]}, and the resonance parameter set is {[d1, d2, d3], [e1, e2, e3]}. [a, a1] can be iterated with the binary division method of [d1, d2, d3], and finally calculated according to [d11, d21, d31] to obtain f1. Furthermore, [b, b1] can be iterated with the binary division method of [d1, d2, d3], and finally calculated according to [d12, d22, d32] to obtain f2, [c, c1] can be iterated with [d1, d2, d3] by binary division, and finally f3 is calculated according to [d13, d23, d33]. Then the steady-state operating frequency set of the resonant converter is {f1, f2, f3}, and the calculation parameter group is {[a, a1], [d11, d21, d31]} or {[b, b1], [d12, d22, d32]}, {[c, c1], [d13, d23, d33]}. Similarly, the voltage group in the voltage parameter set can also select [e1, e2, e3] in the resonance parameter set for binary division iterative calculation. In this embodiment, to ensure the accuracy of the data, the voltage group in the voltage parameter set and the resonance parameter group in the resonance parameter set can be traversed to obtain the steady-state operating frequency set.

[0057] Step S103 , using each of the steady-state operating frequencies and its corresponding voltage group and equivalent resonance parameter group, calculate and obtain the steady-state resonant current peak value corresponding to the resonant converter at the steady-state operating frequency.

[0058] That is, the calculation parameter group corresponding to the calculation of the steady-state operating frequency is used to calculate the steady-state resonant current peak value corresponding to the resonant converter at the steady-state operating frequency. The specific calculation process will be described below. Taking the above example, when the steady-state operating frequency is f1, its corresponding voltage group is [a, a1], and its corresponding equivalent resonant parameter group is [d11, d21, d31]. The steady-state resonant current peak value is calculated using f1, [a, a1], [[d11, d21, d31]]; when the steady-state operating frequency is f2, its corresponding voltage group is [b, b1], and its corresponding resonant parameter group is [d12, d22, d32]. The steady-state resonant current peak value is calculated again using f2, [b, b1], [d12, d22, d32].

[0059] Step S104 , obtaining a calculation parameter group corresponding to when the steady-state operating frequency in the steady-state operating frequency set meets a first preset condition and the corresponding steady-state resonant current peak meets a second preset condition, to obtain multiple calculation parameter groups.

[0060] The first preset condition may be a steady-state operating frequency threshold value set according to actual operating conditions, and the second preset condition may be a steady-state resonant current peak threshold value set according to actual operating conditions.

[0061] When the calculated steady-state operating frequency satisfies the first preset condition, and the calculated steady-state resonant current peak value corresponding to the current steady-state operating frequency satisfies the second preset condition, the calculation parameter group corresponding to the calculated steady-state operating frequency is recorded. When the calculated steady-state operating frequency does not satisfy the first preset condition, or the calculated steady-state resonant current peak value corresponding to the current steady-state operating frequency does not satisfy the second preset condition, no recording is performed. All steady-state operating frequencies in the steady-state operating frequency set, and the steady-state resonant current peak values ​​corresponding to the steady-state operating frequencies, are judged according to the above method, thereby obtaining multiple calculation parameter groups that meet the above conditions.

[0062] Step S105 : selecting an optimal equivalent resonance parameter group from the multiple calculation parameter groups, wherein the optimal equivalent resonance parameter group is the equivalent resonance parameter group corresponding to the largest number of different voltage groups among the multiple calculation parameter groups.

[0063] Specifically, from the multiple sets of calculation parameter groups that meet the conditions, find the set of equivalent resonance parameter groups that meet the conditions most under different voltage conditions, that is, the equivalent resonance parameter group that corresponds to the largest number of different voltage groups among the multiple sets of calculation parameter groups. The equivalent series resonant inductance L in the optimal equivalent resonance parameter group is s , equivalent series resonant capacitor C s and the equivalent parallel resonant capacitor C p The corresponding parameter value is the optimal equivalent resonance parameter.

[0064] Furthermore, if there are multiple groups of equivalent resonance parameter sets that meet the most conditions under different voltage conditions, that is, there are multiple groups of equivalent resonance parameter sets corresponding to the same number of voltage groups, then the multiple groups of resonance parameters can be simultaneously determined as the optimal equivalent resonance parameters, or any one of them can be determined as the optimal equivalent resonance parameter.

[0065] If there are no equivalent resonance parameter sets that meet the most conditions under different voltage conditions, that is, the number of voltage groups corresponding to the equivalent resonance parameter sets does not meet the preset number, then re-establish the voltage parameter set and the resonance parameter set, and repeat steps S101 to S105;

[0066] Similarly, if there is no equivalent resonance parameter group that meets the conditions under different voltage conditions, the voltage parameter set and the resonance parameter set are re-established, and steps S101-S105 are repeated, or the first preset condition is changed, that is, the steady-state operating frequency threshold set according to the actual working conditions can be changed, or the second preset condition is changed, that is, the steady-state resonance current peak threshold set according to the actual working conditions can be changed, or both can be changed at the same time.

[0067] Using the selected optimal equivalent resonance parameter set as the actual resonance parameters during actual operation can ensure that the steady-state operating frequency and steady-state resonant current peak value are within the desired steady-state operating frequency and steady-state resonant current peak value ranges under different input and output voltages. This is in contrast to the prior art method of directly calculating the theoretical resonance parameters for the circuit topology based on the desired operating frequency. This results in the inability to accurately control the resonant cavity current when the calculated theoretical resonance parameters are applied to actual operation, resulting in overshoot or undershoot of the resonant current.

[0068] In this embodiment, a voltage parameter set and a resonance parameter set are first established, and the voltage groups in the voltage parameter set and the resonance parameter groups in the resonance parameter set are traversed to calculate a steady-state operating frequency set of the resonant converter. The steady-state resonant current peak value corresponding to the resonant converter at the steady-state operating frequency is calculated using each steady-state operating frequency and its corresponding voltage group and equivalent resonance parameter group. Secondly, a calculation parameter group corresponding to the steady-state operating frequency set when the steady-state operating frequency satisfies a first preset condition and the corresponding steady-state resonant current peak value satisfies a second preset condition is obtained to obtain multiple calculation parameter groups. Finally, an optimal equivalent resonant parameter group is selected from the multiple calculation parameter groups, wherein the optimal equivalent resonant parameter group is the equivalent resonant parameter group with the largest number of corresponding different voltage groups in the multiple calculation parameter groups. By selecting the optimal equivalent resonant parameter group, it is achieved that under different input and output voltages, the steady-state operating frequency and the steady-state resonant current peak value during operation are within the required steady-state operating frequency and the required steady-state resonant current peak value range, and the resonant cavity current can be accurately controlled without causing the resonant current to overshoot or be too small, thereby affecting the control effect of the state trajectory algorithm.

[0069] As an optional implementation manner, in an embodiment of the present invention, the obtaining of the calculation parameter group corresponding to the steady-state operating frequency in the steady-state operating frequency set when the steady-state operating frequency satisfies the first preset condition and the corresponding steady-state resonant current peak satisfies the second preset condition, obtaining multiple groups of calculation parameter groups, including:

[0070] It is determined group by group whether the steady-state operating frequency corresponding to each calculation parameter group meets the first preset condition, and whether the corresponding steady-state resonant current peak meets the second preset condition.

[0071] The calculation parameter groups corresponding to the steady-state operating frequency satisfying the first preset condition and the steady-state resonant current peak satisfying the second preset condition are recorded to obtain the multiple calculation parameter groups.

[0072] like Figure 4 As shown, when the calculated steady-state operating frequency meets the first preset condition, and the calculated steady-state resonant current peak value corresponding to the current steady-state operating frequency meets the second preset condition, the calculation parameter group corresponding to the calculated steady-state operating frequency is recorded. When the calculated steady-state operating frequency does not meet the first preset condition, or the calculated steady-state resonant current peak value corresponding to the current steady-state operating frequency does not meet the second preset condition, no recording is performed. All steady-state operating frequencies in the steady-state operating frequency set and the steady-state resonant current peak values ​​corresponding to the steady-state operating frequencies are judged according to the above method, thereby obtaining multiple groups of calculation parameter groups that meet the above conditions, and finally selecting the optimal equivalent resonant parameters from the multiple groups of calculation parameters.

[0073] As an optional implementation manner, in the embodiment of the present invention, the steady-state operating frequency is calculated by the following formula:

[0074]

[0075] V o is the output voltage of the resonant converter, V in is the input voltage of the resonant converter, n is the primary-to-secondary turns ratio of the transformer in the resonant converter, k in is the voltage proportional coefficient, sin(θ / 2) is the empirical coefficient, f n is the steady-state operating frequency of the resonant converter, C n is the capacitance ratio of the resonant converter, and Q is the quality factor.

[0076] like Figure 3 As shown, according to the fundamental wave equivalent method, H(s) is defined as the fundamental wave output voltage V of the equivalent circuit. Cp1 The equivalent circuit fundamental input voltage V AB1 The transfer function between:

[0077]

[0078] Among them, R e is the equivalent resistance, C e is the equivalent capacitance, L s 、C s 、C p are the equivalent series resonant inductor, the equivalent series resonant capacitor and the equivalent parallel resonant capacitor respectively, and s is the complex variable in the transfer function in the equivalent circuit of the resonant converter.

[0079] The expression for the equivalent AC circuit input impedance is:

[0080]

[0081] Furthermore, H(s) is simplified to obtain the normalized voltage gain function G dc :

[0082]

[0083] in, j is a plural number, f s is the actual operating frequency of the resonant converter, f r is the resonant frequency in the equivalent circuit.

[0084] The absolute value of the modulus of the normalized voltage gain function can be further simplified to:

[0085]

[0086] According to the resonant converter voltage transfer ratio, we can obtain:

[0087]

[0088] Wherein, θ is the normalized value of the conduction angle of the secondary rectifier bridge in one switching cycle, and its value range is generally 100°-150°. In this embodiment, the empirical coefficient sin(θ / 2) is a constant value, and the voltage proportional coefficient k in is the fundamental input voltage V of the resonant converter equivalent circuit AB1 The resonant converter input voltage V in The ratio of, that is,

[0089] As an optional implementation manner, in an embodiment of the present invention, the calculating of the steady-state resonant current peak value corresponding to the resonant converter at the steady-state operating frequency using each of the steady-state operating frequencies and their corresponding voltage group and resonance parameter group includes:

[0090] Obtain the resonant frequency in the resonant converter equivalent circuit; calculate the actual operating frequency of the resonant converter using the steady-state operating frequency and the resonant frequency; calculate the complex variable in the transfer function in the resonant converter equivalent circuit based on the actual operating frequency; and calculate the steady-state resonant current peak based on the complex variable, the voltage group, and the resonant parameter group.

[0091] Specifically, the resonant frequency f in the resonant converter equivalent circuit is r is the equivalent series resonant inductor L in this embodiment s and the equivalent series resonant capacitor C s The resonant frequency, that is,

[0092] The actual operating frequency f of the resonant converter s The steady-state operating frequency f n and the resonant frequency f r Calculated, that is, f s =f n ·f r .

[0093] Furthermore, according to ω=2πf s j, s = ωj to obtain the complex variable s in the transfer function of the equivalent circuit of the resonant converter.

[0094] As an optional implementation manner, in an embodiment of the present invention, the peak value of the steady-state resonant current is calculated by the following formula:

[0095]

[0096] I Ls is the peak value of the steady-state resonant current, L s is the corresponding inductance in the equivalent circuit of the resonant converter, C s 、C p 、C e are the corresponding capacitors in the equivalent circuit of the resonant converter, R e is the corresponding resistance in the equivalent circuit of the resonant converter, s is the complex variable in the transfer function in the equivalent circuit of the resonant converter, and π is a constant.

[0097] In the fundamental wave equivalent circuit, the peak value of the steady-state resonant current can be expressed as the ratio of the fundamental wave input voltage of the equivalent circuit to the input impedance modulus, as shown below:

[0098]

[0099] Where s = ωj, ω = 2πf s j, ω is the frequency, and j is an imaginary number.

[0100] As described above, the steady-state operating frequency f of the resonant converter is calculated using the voltage group in the voltage parameter set and the resonance parameter group in the resonance parameter set. n ,according to Get the actual operating frequency f of the resonant converter s , and then calculate the complex variable s.

[0101] As an optional implementation, in the embodiment of the present invention, the voltage proportional coefficient k in is the fundamental input voltage V of the resonant converter equivalent circuit AB1 The resonant converter input voltage V in The ratio of, that is, Different input voltages of the resonant converter can be selected according to actual work. Through equivalent transformation, the primary voltage and current of the transformer are transformed by Fourier transform, and their fundamental components are taken as the fundamental input voltage of the resonant converter equivalent circuit.

[0102] As an overall solution of this embodiment, Figure 4As shown, first determine whether all voltage groups in the voltage parameter set have been calculated. If not all of them participate in the calculation, select a new set of voltage groups from the voltage parameter set; perform binary iterative calculation on the selected voltage group and the resonance parameter group in the resonance parameter set, and determine whether all of the resonance parameter groups in the resonance parameter set have been calculated. If not all of them participate in the calculation, select a new set of resonance parameter groups from the resonance parameter set; calculate the steady-state operating frequency and the steady-state resonant current peak value based on the selected new voltage group and the new resonance parameter group, and determine whether the steady-state operating frequency meets the first preset condition and the corresponding steady-state resonant current peak value. Whether the peak value of the state resonant current meets the second preset condition. If both are met, the voltage group currently participating in the calculation and the equivalent resonant parameter group after the dichotomy change, that is, the calculation parameter group, are recorded; if not, the calculation parameter group participating in the calculation is abandoned, and a new resonant parameter group is selected; when all the resonant parameter groups in the resonant parameter set have been calculated, a new voltage group is selected from the voltage parameter set again. If all the voltage groups in the voltage parameter set have been calculated, all the recorded calculation parameter groups are obtained from the recorded system or device, and the optimal equivalent resonant parameter group is selected from all the recorded calculation parameter groups.

[0103] Example 2

[0104] This embodiment provides a device for determining the resonance parameters of a resonant converter. The device can be used to execute the method for determining the resonance parameters of a resonant converter in the above embodiment 1. The device can be set inside a server or other device, and the modules cooperate with each other to achieve the determination of the resonance parameters of the resonant converter. Figure 5 As shown, the device includes:

[0105] The data module 201 is used to establish a voltage parameter set and a resonance parameter set, wherein the voltage parameter set includes multiple voltage groups, each of which includes an input voltage of the resonant converter and its corresponding output voltage; and the resonance parameter set includes multiple resonance parameter groups, each of which includes a corresponding set of inductors and capacitors in the resonant converter equivalent circuit.

[0106] The frequency module 202 is used to traverse the voltage groups in the voltage parameter set and the resonance parameter groups in the resonance parameter set to calculate a steady-state operating frequency set of the resonant converter, wherein each steady-state operating frequency in the steady-state operating frequency set corresponds to a set of calculation parameter groups, and a set of the calculation parameter groups includes a set of voltage groups and a corresponding set of equivalent resonance parameter groups.

[0107] The peak module 203 is configured to calculate the steady-state resonant current peak value corresponding to the resonant converter at each steady-state operating frequency using its corresponding voltage group and equivalent resonant parameter group.

[0108] The condition module 204 is configured to obtain a calculation parameter group corresponding to when the steady-state operating frequency in the steady-state operating frequency set satisfies a first preset condition and the corresponding steady-state resonant current peak satisfies a second preset condition, thereby obtaining multiple calculation parameter groups.

[0109] The selection module 205 is configured to select an optimal equivalent resonance parameter group from the multiple calculation parameter groups, wherein the optimal equivalent resonance parameter group is the equivalent resonance parameter group corresponding to the largest number of different voltage groups among the multiple calculation parameter groups.

[0110] In this embodiment, a voltage parameter set and a resonance parameter set are first established, and the voltage groups in the voltage parameter set and the resonance parameter groups in the resonance parameter set are traversed to calculate a steady-state operating frequency set of the resonant converter. The steady-state resonant current peak value corresponding to the resonant converter at the steady-state operating frequency is calculated using each steady-state operating frequency and its corresponding voltage group and equivalent resonance parameter group. Secondly, a calculation parameter group corresponding to the steady-state operating frequency set when the steady-state operating frequency satisfies a first preset condition and the corresponding steady-state resonant current peak value satisfies a second preset condition is obtained to obtain multiple calculation parameter groups. Finally, an optimal equivalent resonant parameter group is selected from the multiple calculation parameter groups, wherein the optimal equivalent resonant parameter group is the equivalent resonant parameter group with the largest number of corresponding different voltage groups in the multiple calculation parameter groups. By selecting the optimal equivalent resonant parameter group, it is achieved that under different input and output voltages, the steady-state operating frequency and the steady-state resonant current peak value during operation are within the required steady-state operating frequency and the required steady-state resonant current peak value range, and the resonant cavity current can be accurately controlled without causing the resonant current to overshoot or be too small, thereby affecting the control effect of the state trajectory algorithm.

[0111] As an optional implementation manner, in this embodiment of the present invention, the selection module further includes:

[0112] The judgment module is used to judge whether the steady-state operating frequency corresponding to each calculation parameter group meets the first preset condition, and to judge whether the corresponding steady-state resonant current peak meets the second preset condition.

[0113] The recording module is used to record the calculation parameter groups corresponding to the steady-state operating frequency meeting the first preset condition and the steady-state resonant current peak meeting the second preset condition, to obtain the multiple calculation parameter groups.

[0114] For a detailed description of the above-mentioned device part, please refer to the above-mentioned method embodiment, which will not be repeated here.

[0115] Example 3

[0116] This embodiment provides a computer device, such as Figure 6As shown, the computer device includes a processor 301 and a memory 302, wherein the processor 301 and the memory 302 can be connected via a bus or other means. Figure 6 The bus connection is taken as an example.

[0117] The processor 301 may be a central processing unit (CPU). The processor 301 may also be other general-purpose processors, digital signal processors (DSP), graphics processing units (GPU), embedded neural network processors (NPU), or other dedicated deep learning coprocessors, application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or a combination of the above chips.

[0118] Memory 302, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs, non-transitory computer-executable programs, and modules, such as the method for determining the resonant parameters of a resonant converter according to an embodiment of the present invention, and the corresponding program instructions / modules. Processor 301 executes the non-transitory software programs, instructions, and modules stored in memory 302 to perform various processor functions and data processing, thereby implementing the method for determining the resonant parameters of a resonant converter according to the aforementioned method embodiment.

[0119] The memory 302 may also include a program storage area and a data storage area, wherein the program storage area may store an operating system and applications required for at least one function; the data storage area may store data created by the processor 301, etc. In addition, the memory 302 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other non-volatile solid-state storage device. In some embodiments, the memory 302 may optionally include a memory remotely located relative to the processor 301, and these remote memories may be connected to the processor 301 via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0120] The memory 302 stores one or more modules, which, when executed by the processor 301, perform the following operations: Figure 1 The method for determining the resonant parameters of the resonant converter in the illustrated embodiment.

[0121] For details of the above computer equipment, please refer to Figure 1 The corresponding descriptions and effects in the embodiments shown can be understood and will not be repeated here.

[0122] An embodiment of the present invention further provides a computer-readable storage medium storing computer-executable instructions capable of executing the method for determining the resonant parameters of a resonant converter according to any of the above embodiments. The storage medium may be a magnetic disk, an optical disk, a read-only memory (ROM), a random access memory (RAM), a flash memory, a hard disk drive (HDD), or a solid-state drive (SSD); the storage medium may also include a combination of the above types of memory.

[0123] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will readily appreciate that other variations or modifications based on the above descriptions are possible. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A method for determining resonant parameters of a resonant converter, characterized in that: include: Establishing a voltage parameter set and a resonance parameter set, wherein the voltage parameter set includes multiple voltage groups, each of which includes an input voltage of the resonant converter and a corresponding output voltage thereof; and the resonance parameter set includes multiple resonance parameter groups, each of which includes a corresponding set of inductors and capacitors in an equivalent circuit of the resonant converter; Traversing the voltage groups in the voltage parameter set and the resonance parameter groups in the resonance parameter set, and calculating a steady-state operating frequency set of the resonant converter, wherein each steady-state operating frequency in the steady-state operating frequency set corresponds to a set of calculation parameter groups, and a set of the calculation parameter groups includes a set of voltage groups and a corresponding set of equivalent resonance parameter groups; Calculating the peak value of the steady-state resonant current corresponding to the resonant converter at the steady-state operating frequency using each of the steady-state operating frequencies and the corresponding voltage group and equivalent resonant parameter group; Obtaining a calculation parameter group corresponding to when the steady-state operating frequency in the steady-state operating frequency set satisfies a first preset condition and the corresponding steady-state resonant current peak satisfies a second preset condition, to obtain multiple calculation parameter groups; An optimal equivalent resonance parameter group is selected from the multiple calculation parameter groups, wherein the optimal equivalent resonance parameter group is an equivalent resonance parameter group having the largest number of corresponding different voltage groups among the multiple calculation parameter groups.

2. The method for determining the resonant parameters of a resonant converter according to claim 1, wherein: The obtaining of the calculation parameter groups corresponding to the steady-state operating frequency set when the steady-state operating frequency satisfies the first preset condition and the corresponding steady-state resonant current peak value satisfies the second preset condition, to obtain multiple calculation parameter groups, including: Determining, group by group, whether the steady-state operating frequency corresponding to each calculation parameter group satisfies the first preset condition, and determining whether the corresponding steady-state resonant current peak value satisfies the second preset condition; The calculation parameter groups corresponding to the steady-state operating frequency satisfying the first preset condition and the steady-state resonant current peak satisfying the second preset condition are recorded to obtain the multiple calculation parameter groups.

3. The method for determining the resonant parameters of a resonant converter according to claim 1, wherein: The steady-state operating frequency is calculated by the following formula: V o is the output voltage of the resonant converter, V in is the input voltage of the resonant converter, n is the primary-to-secondary turns ratio of the transformer in the resonant converter, k in is the voltage proportional coefficient, sin(θ / 2) is the empirical coefficient, f n is the steady-state operating frequency of the resonant converter, C n is the capacitance ratio of the resonant converter, and Q is the quality factor.

4. The method for determining the resonant parameters of a resonant converter according to claim 1, wherein: The step of calculating the steady-state resonant current peak value corresponding to the resonant converter at the steady-state operating frequency using each steady-state operating frequency and its corresponding voltage group and equivalent resonant parameter group includes: Obtaining a resonant frequency in an equivalent circuit of the resonant converter; Calculating an actual operating frequency of the resonant converter using the steady-state operating frequency and the resonant frequency; Calculate the complex variables in the transfer function of the resonant converter equivalent circuit according to the actual operating frequency; The steady-state resonant current peak value is obtained by calculation according to the complex variable, the voltage group and the resonant parameter group.

5. The method for determining the resonant parameters of a resonant converter according to claim 4, wherein: The peak value of the steady-state resonant current is calculated by the following formula: I Ls is the peak value of the steady-state resonant current, Ls is the corresponding inductance in the equivalent circuit of the resonant converter, C s 、C p 、C e are the corresponding capacitors in the equivalent circuit of the resonant converter, R e is the corresponding resistance in the equivalent circuit of the resonant converter, s is the complex variable in the transfer function in the equivalent circuit of the resonant converter, and π is a constant.

6. The method for determining the resonant parameters of a resonant converter according to claim 3, wherein: The voltage proportional coefficient is the ratio of the fundamental input voltage of the resonant converter equivalent circuit to the input voltage of the resonant converter.

7. A device for determining resonance parameters of a resonant converter, characterized in that: include: a data module, configured to establish a voltage parameter set and a resonance parameter set, wherein the voltage parameter set includes multiple voltage groups, each of which includes an input voltage of the resonant converter and a corresponding output voltage thereof; and the resonance parameter set includes multiple resonance parameter groups, each of which includes a corresponding set of inductors and capacitors in an equivalent circuit of the resonant converter; a frequency module, configured to traverse the voltage groups in the voltage parameter set and the resonance parameter groups in the resonance parameter set, and calculate a steady-state operating frequency set of the resonant converter, wherein each steady-state operating frequency in the steady-state operating frequency set corresponds to a set of calculation parameter groups, and a set of the calculation parameter groups includes a set of voltage groups and a corresponding set of equivalent resonance parameter groups; A peak module, configured to calculate the steady-state resonant current peak value corresponding to the resonant converter at each steady-state operating frequency using its corresponding voltage group and equivalent resonant parameter group; a condition module, configured to obtain a calculation parameter group corresponding to when the steady-state operating frequency in the steady-state operating frequency set satisfies a first preset condition and the corresponding steady-state resonant current peak satisfies a second preset condition, to obtain multiple calculation parameter groups; The selection module is used to select an optimal equivalent resonance parameter group from the multiple calculation parameter groups, wherein the optimal equivalent resonance parameter group is the equivalent resonance parameter group with the largest number of corresponding different voltage groups among the multiple calculation parameter groups.

8. The device for determining the resonance parameters of a resonant converter according to claim 7, wherein: The selection module also includes: a judgment module, configured to judge, group by group, whether the steady-state operating frequency corresponding to each calculation parameter group satisfies the first preset condition, and to judge whether the corresponding steady-state resonant current peak value satisfies the second preset condition; The recording module is used to record the calculation parameter groups corresponding to the steady-state operating frequency meeting the first preset condition and the steady-state resonant current peak meeting the second preset condition, to obtain the multiple calculation parameter groups.

9. A computer device, characterized in that: include: A memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the method for determining the resonant parameters of a resonant converter according to any one of claims 1 to 6 by executing the computer instructions.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable the computer to execute the method for determining the resonant parameters of a resonant converter according to any one of claims 1 to 6.

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