CN113824330B - LLC resonant converter based on variable inductance - Google Patents

LLC resonant converter based on variable inductance Download PDF

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Publication number
CN113824330B
CN113824330B CN202111106665.7A CN202111106665A CN113824330B CN 113824330 B CN113824330 B CN 113824330B CN 202111106665 A CN202111106665 A CN 202111106665A CN 113824330 B CN113824330 B CN 113824330B
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inductance
current
bias
circuit
transformer
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CN113824330A (en
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刘晓东
李宁
张君扬
刘宿城
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Anhui University of Technology AHUT
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Anhui University of Technology AHUT
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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M3/00—Conversion of dc power input into dc power output
    • H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
    • H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
    • H02M3/28—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
    • H02M3/325—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
    • H02M3/335—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
    • H02M3/33569—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F27/00—Details of transformers or inductances, in general
    • H01F27/24—Magnetic cores
    • H01F27/26—Fastening parts of the core together; Fastening or mounting the core on casing or support
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F27/00—Details of transformers or inductances, in general
    • H01F27/28—Coils; Windings; Conductive connections
    • H01F27/30—Fastening or clamping coils, windings, or parts thereof together; Fastening or mounting coils or windings on core, casing, or other support
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
    • Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

The invention discloses an LLC resonant converter based on variable inductance in the technical field of power electronic converters, which comprises a magnetic core, wherein the magnetic core is double-E-shaped, and the magnetic core comprises: the primary winding, the secondary winding, the bias windings A and B and the middle magnetic circuit are provided with air gaps; by changing the current of the bias winding, the magnetic conductivity of the material can be changed, the excitation inductance can be changed, and the ratio of the excitation inductance can be changed. The bias windings are wound on the side branches in the same direction, and the alternating voltage generated by mutual inductance is counteracted through the induction center branch; the bias winding needs an extra constant current source, comprises a main circuit and a control circuit, the mode can reduce the loss of a resonant cavity, improve the light load efficiency, enable the efficiency of the converter in a full load range to be maintained at a higher level, has a simple circuit structure, achieves the purpose of reducing the circuit cost, does not need to modify the main part of the transformer, and does not influence other parameters of the transformer such as primary leakage inductance of the transformer.

Description

LLC resonant converter based on variable inductance
Technical Field
The invention relates to the technical field of power electronic converters, in particular to an LLC resonant converter based on variable inductance;
background
With the rapid development of power electronics technology, the efficiency of DC/DC converters in full-load and half-load situations has received a great deal of attention. High power, high efficiency and high power density have been the main development direction and pursuit targets of switching power supplies. LLC resonant converters have excellent characteristics in terms of soft switching, but under light load conditions, the switching frequency needs to be adjusted to several times the resonant frequency to maintain the target output, which can greatly increase drive loss, switching loss and high frequency magnetic loss, resulting in low light load efficiency.
Aiming at the problem of lower light load efficiency of LLC resonant converters, a great deal of research work is done by industry scholars and related personnel, such as the adoption of the intermittent mode control based on the voltage hysteresis has obvious effect, but the intermittent mode control based on the voltage hysteresis possibly causes current noise, influences the load, and meanwhile, the adverse effect brought by the control is that the output voltage ripple is increased for voltage type output application, so that the efficiency improvement range is relatively smaller. For example, a combined control strategy of PFM+PWM is adopted, and the LLC resonant converter automatically works in a PWM state in light load, so that the soft switching advantage of the LLC resonant converter is lost;
disclosure of Invention
The present invention aims to provide an LLC resonant converter based on variable inductance to solve the above-mentioned problems in the background art;
in order to achieve the above purpose, the present invention provides the following technical solutions: a control method of LLC resonant converter structure adjusts the exciting inductance ratio k by judging the output current Io in real time, so that the exciting inductance ratio k is adapted to the current load power interval; where k=lm/Lr, where Lm is the excitation inductance and Lr is the resonance inductance
When the output current Io meets the value that Io is less than or equal to Iswitch, setting the current excitation inductance ratio k to be k1; in the present invention, the value of the load interval segmentation point Iswitch is:
wherein Gmax is the required maximum voltage gain, vo is the output voltage, n is the transformer transformation ratio, and Cr is the resonant capacitance of the LLC resonant network.
Based on the method, the invention provides an LLC resonant converter structure, which comprises a main circuit and a control circuit:
the LLC resonant network comprises a resonant inductor Lr, a resonant capacitor Cr and an excitation inductor Lm which can be changed along with bias current;
the high-frequency transformer consists of a high-frequency transformer, the excitation inductance of which can be changed, and the transformer is characterized in that: the double E-shaped magnetic core is adopted, windings on the primary side and the secondary side are wound on a center leg, bias windings A and B of the variable inductor have the same number of turns, are wound on side branches in the same direction, and offset alternating voltage is counteracted through induction of the center branch. The DC current injected by the bias winding causes saturation of each leg, and the DC control current generates DC bias magnetic flux density inside the magnetic core, thereby changing the DC working point around the inflection point of the B-H curve to adjust the magnetic conductivity of the material. Thus, as the bias current increases, the permeability of the material decreases, and, according to the inductive expression,n is the number of turns, l is the loop length of the magnetic circuit, ae is the cross-sectional area of the magnetic flux. The final excitation inductance Lm becomes smaller; the high-frequency transformer is provided with a control switch in a primary loop, wherein the control switch is controlled by a control circuit and is used for determining whether a bias current source is conducted or not and corresponds to an excitation inductance Lm.
The control circuit is used for adjusting the states of the control switches according to the magnitude of the output current Io of the output end, and adjusting whether the bias power supply is conducted or not so as to enable the exciting inductance ratio k to be matched with the magnitude of the current output current Io.
Further, in the above structure, a control program is preset in the control circuit, and the control program controls in the following manner:
when the output current Io meets the value that Io is less than or equal to Iswitch, the current excitation inductance ratio k2 is adjusted to k1 by sending a switching signal to the control switch, and the bias power supply does not work any more.
Further, in the above-described structure, the control circuit portion sequentially includes: the digital signal processor comprises an output voltage and current sampling circuit, a DSP digital controller, a bias current source and a driving circuit;
in the constant voltage working mode, the driving circuit is used for receiving a control signal of the DSP and driving the high-frequency transformer to control the switch to perform corresponding switching action so as to adjust the current exciting inductance ratio k2 to k1.
The beneficial effects are that:
according to the technical scheme, in the transformer with the double E-shaped magnetic cores, the primary side and the secondary side are wound on the central branch, the offset winding is added on the side branch, the middle branch is provided with an air gap, and the side branch is not provided with an air gap. The bias current source is controlled to be switched on and off by adopting a switching control strategy, so that LLC resonance parameters can be flexibly changed, the loss of a resonant cavity is reduced by increasing the exciting inductance ratio kj in a light load area, the light load efficiency is improved, the efficiency of the converter in a full load range can be maintained at a higher level, the circuit structure is simple, and the aim of reducing the circuit cost is fulfilled.
The technical scheme of the invention further controls the conduction or non-conduction of the bias current source by controlling the on-off of the switch, thereby realizing the variation of the excitation inductance. When in heavy load, the exciting inductance is smaller, so that the k value is smaller, the transformer can obtain a larger gain adjustment range, when in light load, the exciting inductance is increased, so that the k value is increased, the circulating current of the resonant cavity can be reduced, the loss is reduced, and the light load efficiency is improved, which is the required characteristic of the resonant charging power supply. The parameters of the excitation inductance of the transformer are changed by adjusting the bias current, the main body part of the transformer is not required to be modified, other parameters of the transformer such as primary leakage inductance of the transformer cannot be influenced, and the whole circuit structure is simple.
Drawings
FIG. 1 is a diagram of the overall structure of a variable inductance based LLC resonant converter according to the present invention;
FIG. 2 is a block diagram of a transformer of the present invention;
FIG. 3 is a logic flow diagram of a method for controlling the switching of a transformer according to the present invention;
FIG. 4 is a block diagram of the proposed variable inductance LLC resonant converter closed loop control;
fig. 5 is a graph of the dc gain of the proposed variable inductance LLC resonant converter.
The specific meaning of each marked part in the figure is as follows:
1. a main circuit; 2. an input side inverter network; 3. LLC resonant network; 4. a transformer; 5. a secondary side rectifying and filtering network; 6. an output end; 7. a transformer control switch; 8. a control circuit; 9. an output voltage current sampling circuit; 10. a DSP digital controller; 11. a driving circuit; 12. a bias power supply; 13. a controllable constant current source;
Detailed Description
The following description of the embodiments of the present invention will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all embodiments of the invention; all other embodiments, based on the embodiments of the invention, which a person of ordinary skill in the art would obtain without inventive faculty, are within the scope of the invention;
referring to fig. 1 to 5, the present invention provides an LLC resonant converter based on variable inductance: the LLC resonant converter structure in the present embodiment as shown in FIG. 1 comprises two major parts, namely a main circuit 1 and a control circuit 8.
The main circuit 1 includes, in order: an input side inverter network 2, an LLC resonant network 3, a transformer 4, a secondary side rectifying and filtering network 5, an output end 6 and a transformer control switch 7.
The control circuit 8 includes, in order: an output voltage and current sampling circuit 9, a DSP digital controller 10, a driving circuit 11 and a controllable constant current source 12.
The LLC resonant network includes a resonant inductance Lr, a resonant capacitance Cr, and an excitation inductance Lm that can vary with bias current.
The transformer consists of a transformer, the excitation inductance of which can be changed, and the transformer is characterized in that: the double E-shaped magnetic core is adopted, windings on the primary side and the secondary side are wound on a center leg, bias windings A and B of the variable inductor have the same number of turns, are wound on side branches in the same direction, and offset alternating voltage is counteracted through induction of the center branch. The DC current injected by the bias winding causes saturation of each leg, and the DC control current generates DC bias magnetic flux density inside the magnetic core, thereby changing the DC working point around the inflection point of the B-H curve to adjust the magnetic conductivity of the material. Thus as the bias current increases, the permeability of the material decreases, according to the inductive expressionN is the number of turns, l is the loop length of the magnetic circuit, ae is the cross-sectional area of the magnetic flux. Finally Lm will become smaller; the high-frequency transformer is provided with a control switch in a primary loop, wherein the control switch is controlled by a control circuit and is used for determining whether a bias current source is conducted or not and corresponds to an excitation inductance Lm.
The excitation inductance Lm of the LLC resonant network is determined by the magnitude of the bias current.
The control circuit adjusts the exciting inductance ratio k by judging the output current in real time, wherein k=lm/Lr, lm is the exciting inductance of the LLC resonant network, and Lr is the resonant inductance of the LLC resonant network. The control circuit changes the excitation inductance Lm of the LLC resonant network by switching the magnitude of the detected output current, so as to adjust the magnitude of the excitation inductance ratio k.
Fig. 2 is a schematic diagram of a transformer.
As shown in fig. 2, the proposed variable inductor is based on a double "E" core structure that includes an air gap at the center leg. The main inductor is wound on the center pin, and the symmetrical offset windings are wound on the two side arms of the "E" core. The bias windings are connected in series with opposite polarity to cancel the ac voltage induced by the center leg. The bias will magnetize the (unmagnetized) path of the ferrite core as the magnetic flux path created by the bias winding surrounds the upper and lower portions of the side arms and ferrite core. A relatively small bias is sufficient to change the effective permeability of the center leg winding and thus the excitation inductance.
The control circuit adjusts the exciting inductance ratio k by judging the output current Io in real time as follows:
when the output current Io meets the value that Io is less than or equal to Iswitch, the current excitation inductance ratio k is set to be k1.
According to the transformer used in the present embodiment, the k value may be k1 or k2, and the two k values correspond to the two load segments, so that only one load segment value is indicated by Iswitch in the present embodiment.
The dividing of the load interval comprises the following steps:
step one, reasonably selecting an inductance ratio kj according to requirements, and determining relevant parameters of the LLC resonant converter by using rated working points: the transformer transformation ratio n, the required maximum voltage gain Gmax, the quality factor maximum value Qmax, the resonant inductance Lr and the resonant capacitance Cr.
In this embodiment, a rated operating point (heavy load region) is used to determine that the k value of the appropriate heavy load region is kmin, and the k value of the light load region is kmax, that is, k2=kmin, k1=2k2=2kmin=kmax
Step two: substituting the inductance ratio k=kj into the following maximum quality factor calculation formula to obtain a corresponding maximum quality factor Qmax-j.
In this embodiment, the inductance value k=k1=2kmin of the light load region is substituted into the following maximum quality factor calculation formula
Deriving a corresponding maximum quality factor Q max-1 ：
Step three: by mixing the above Q max-1 Substituting the following relation between the figure of merit and the output power Po and the output voltage Vo,
determining that the light load area corresponds to the maximum power point Po-switch,
in order to ensure that the gain requirement can be met before and after the inductance change, the Iswitch is obtained by taking 80% -90% of descending margin for the Iswitch, and then the Iswitch= (80% -90%) Iswitch theory is obtained.
As shown in fig. 1 to 5, the control circuit 8 includes, in order: an output voltage and current sampling circuit 9, a DSP digital controller 10, a driving circuit 11 and a controllable constant current source 12.
In the heavy load region, the LLC resonant converter has a high voltage gain requirement, and the converter efficiency is at a high level in the region, so that the LLC resonant converter operates with a small k value.
In the light load region, the LLC resonant converter has reduced voltage gain requirements, while in this region the converter efficiency level is lower and therefore is put into operation at a large k value.
As shown in fig. 4 and 1, the control circuit controls the main circuit as follows:
step one: the output voltage and current sampling circuit samples the output voltage Vo and the output current Io at the output end of the main circuit, performs analog-digital conversion, and sends the sampled output voltage Vo and the sampled output current Io to the DSP digital controller 10;
step two: the DSP digital controller 10 takes the output voltage Vo and the current Io as input signals of an internal digital closed-loop control program, performs closed-loop control on a main circuit, and simultaneously judges a current load interval in real time according to the output voltage Vo and the output current Io;
step three: outputting symmetrical PWM control signals with corresponding frequencies to the driving circuit 11 according to the calculation result of the digital closed-loop controller in the second step to drive the switching tube of the inversion network to be turned on and off, so as to adjust the direct-current voltage at the output side; meanwhile, a corresponding switching control signal is output to the driving circuit 11 according to the real-time judging result of the load area, and the driving circuit 11 drives the transformer control switch 7 to perform corresponding switching action.
As shown in fig. 3, which is a logic flow chart of a transformer Switching control method, the DSP digital controller 10 receives the output voltage Vo and the output current Io acquired and subjected to analog-to-digital conversion by the output voltage current sampling circuit 9, and compares the output voltage Vo and the output current Io with the load power interval segmentation point Iswitch according to the output voltage Vo and the output current Io, in this embodiment, when Io is less than or equal to Iswitch, the DSP digital controller 10 does not send a Switching signal, the main circuit will not switch, the bias circuit is in circuit break, the k value is kept as k1, and the circuit continues to operate in a light load area; when Io > Iswitch, the DSP digital controller 10 sends a Switching signal, the main circuit switches the bias circuit on, the k value is switched to k2, and the circuit is switched to the heavy load area.
The reference numerals in fig. 4 are explained as follows: vref-voltage reference, iref-current reference, vo-FB-output voltage Vo feedback value, io-FB-output current Io feedback value.
Fig. 5 is a graph of dc gain of the LLC resonant converter corresponding to the above dc voltage gain formula under different operating conditions, where the dc gain curve corresponding to k=3 is actually applied to the heavy load region, and it can be seen from the graph that the curve can meet the maximum gain requirement, so that the curve works in the inductive region, and the MOS transistor zero voltage turn-on (ZVS) can be realized. The dc gain curve corresponding to k=6 is actually applied in the light load region, so as to ensure that the converter can still meet the maximum gain requirement when switching to the state of large k value.
The reference numerals in fig. 5 are explained as follows: gmax—required maximum voltage gain, gmin—required minimum voltage gain, fn—normalized voltage gain, qmax—k=3 corresponds to the maximum quality factor, q1max—k=6 corresponds to the maximum quality factor.
In the description of the present specification, the descriptions of the terms "one embodiment," "example," "specific example," and the like, mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention; in this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples; furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples;
the preferred embodiments of the invention disclosed above are merely intended to help illustrate the invention; the preferred embodiments are not exhaustive or to limit the invention to the precise embodiments disclosed; obviously, many modifications and variations are possible in light of the above teachings; the embodiments were chosen and described in order to best explain the principles of the invention and the practical application, to thereby enable others skilled in the art to best understand and utilize the invention; the invention is limited only by the claims and the full scope and equivalents thereof.

Claims (3)

1. LLC resonant converter based on variable inductance, its characterized in that: including the magnetic core, the magnetic core is two "E" type, and the magnetic core includes: the primary winding, the secondary winding, the bias windings A and B and the middle magnetic circuit are provided with air gaps; the excitation inductance is changed by changing the current of the bias winding;
the bias winding requires an additional constant current source;
when in heavy load, the value of the excitation inductance Lm is Lm-2; in light load, the value of the excitation inductance Lm is Lm-1; before the switching signal arrives, when the circuit is in heavy load, the constant current source of the bias winding always works, and the exciting inductance Lm value is Lm-2; when the switching signal arrives, the constant current source of the circuit bias winding is disconnected, and the exciting inductance Lm value is Lm-1;
the control program controls as follows: according to the output current, when the output current Io meets the condition that Io is less than or equal to Iswitch, the output current Io is the current when the control switch is closed, and the current excitation inductance ratio k2 is adjusted to k1 by sending a switching signal to the control switch; k1 =lm-1/Lr, k2=lm-2/Lr, lm-1, lm-2 is the resonant inductance, and Lm-2 is the value of the excitation inductance Lm at light and heavy loads, respectively.
2. A variable inductance based LLC resonant converter in accordance with claim 1, wherein: the bias windings are wound on the side branches in the same direction, and the alternating voltage generated by mutual inductance is counteracted through the induction center branch.
3. A variable inductance based LLC resonant converter in accordance with claim 1, wherein: the LLC resonant network comprises a resonant inductor Lr, a resonant capacitor Cr and a variable excitation inductor Lm;
the exciting inductance of the high-frequency transformer can be changed, the transformer adopts a double-E-shaped magnetic core, the windings on the primary side and the secondary side are wound on a center leg, the bias windings A and B of the variable inductance have the same number of turns, are wound on side branches in the same direction, and offset alternating voltage through the induction center branch; the DC current injected by the bias winding causes the saturation of each side leg part, and the DC control current generates DC bias magnetic flux density in the magnetic core, so that DC working points around the inflection point of the B-H curve are changed to adjust the magnetic conductivity of the material; thus as the bias current increases, the permeability of the material decreases and finally Lm becomes smaller, noting that from the initial value, a 50% rate of change is appropriate; because the slope between the inductance and the injection current gradually decreases from around 50%; to achieve lower Lm values, excessive injection current is required, which means ineffective; if the inductance continues to drop, more current is required, and more loss is generated; the high-frequency transformer is provided with a control switch in a primary loop, wherein the control switch is controlled by a control circuit and is used for determining whether a bias current source is conducted or not and corresponds to an excitation inductance Lm;
the control circuit adjusts the working state of the control switch by sampling the output current Io so as to enable the exciting inductance ratio k to be matched with the current output current Io.
CN202111106665.7A 2021-09-22 2021-09-22 LLC resonant converter based on variable inductance Active CN113824330B (en)

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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106411142A (en) * 2016-10-12 2017-02-15 杭州电子科技大学 LLC resonant converter with wide load range
CN108667300A (en) * 2017-05-17 2018-10-16 湖南工程学院 A kind of magnetizing inductance variable L LC resonance transformer
CN109873562A (en) * 2019-02-11 2019-06-11 安徽工业大学 A kind of LLC resonant converter structure and its control method
CN214045448U (en) * 2020-12-24 2021-08-24 锦浪科技股份有限公司 LLC resonant converter

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106411142A (en) * 2016-10-12 2017-02-15 杭州电子科技大学 LLC resonant converter with wide load range
CN108667300A (en) * 2017-05-17 2018-10-16 湖南工程学院 A kind of magnetizing inductance variable L LC resonance transformer
CN109873562A (en) * 2019-02-11 2019-06-11 安徽工业大学 A kind of LLC resonant converter structure and its control method
CN214045448U (en) * 2020-12-24 2021-08-24 锦浪科技股份有限公司 LLC resonant converter

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
基于可变电感的变频ＬＬＣ 谐振变换器交错并联技术;陈宗祥等;《电机与控制学报》;第第24卷卷(第第12期期);第97-105页 *

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