CN108365755B - Current-sharing adjusting method for interleaved parallel LLC circuit - Google Patents

Current-sharing adjusting method for interleaved parallel LLC circuit Download PDF

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CN108365755B
CN108365755B CN201810195443.9A CN201810195443A CN108365755B CN 108365755 B CN108365755 B CN 108365755B CN 201810195443 A CN201810195443 A CN 201810195443A CN 108365755 B CN108365755 B CN 108365755B
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CN108365755A (en
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周强
阮世良
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Shenzhen Energy Efficiency Electrical Technology Co.,Ltd.
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Shenzhen Gospell Electric Technology Co Ltd
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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
    • 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
    • H02M3/285—Single converters with a plurality of output stages connected in parallel

Abstract

The invention discloses a current-sharing adjusting method of a staggered parallel LLC circuit, wherein the staggered parallel LLC circuit comprises a plurality of LLC branches which are staggered and connected in parallel, and the current difference or the voltage difference of each LLC branch is detected in real time to obtain an error factor e; and according to the error factor e, the duty ratio D of each LLC branch is adjusted through negative feedback, the gain of each LLC branch is changed, and the current-sharing adjustment of the interleaved parallel LLC circuits is realized. The invention obtains the adjustment quantity of the duty ratio by detecting the unequal flow difference value of each LLC branch in real time and calculating, and can realize the equal flow control of different parallel LLC circuits.

Description

Current-sharing adjusting method for interleaved parallel LLC circuit
[ technical field ]
The invention relates to a staggered parallel LLC circuit, in particular to a current sharing regulation method of the staggered parallel LLC circuit.
[ background art ]
The LLC circuit can realize soft switching in the full load range around the resonant switching frequency, and therefore high power density can be achieved through high switching frequencies, with increasingly wider applications. However, in high-power applications, the magnetic components are enlarged, the output current ripple is large, a large output filter capacitor is required, and the final result is that the power density is reduced and the cost is increased. To solve this problem, a staggered series-parallel connection of multiple LLC circuits is generated, wherein the most common topology is the staggered parallel connection of two LLC circuits. The multiple parallel-connected LLCs keep the same switching frequency and are staggered with each other by certain phase, so that the output current ripple is greatly reduced. In the design, the power density can be greatly improved and the cost is saved by adopting a staggered parallel LLC topology.
But the interleaved LLC topology can cause the problem of multi-path current sharing. Because the magnetic devices of the multiple components are difficult to be completely consistent, including the difference of parasitic parameters of other switching devices and the like, the non-uniform current of a plurality of parallel LLC circuits is often caused. Uneven flow can cause excessive heating of the over-current branch, and the risk of device damage is brought. The most common control method for LLC circuits is PFM control, but since interleaving maintains the same frequency of multiple paths, it becomes difficult to implement current sharing for multiple interleaved parallel LLC circuits.
The most common three LLC parallel modes: the input parallel output is parallel, the input series output is parallel, and the input parallel output is series.
The invention with the publication number of CN103780081A discloses an interleaved LLC current-sharing converter. The interleaved LLC current sharing converter comprises: the interleaved LLC circuit is formed by connecting an even number of LLC circuits in parallel; and a plurality of windings in the same number as the LLC circuit, wherein: the first polarity end of the output direct current side of each LLC circuit jointly forms a first output end; the first ends of the windings together form a second output end; a first half of the plurality of windings encircles the magnetic core in a first direction and a second half of the plurality of windings encircles the magnetic core in a second direction; the inductance values of each of the plurality of windings are equal, and a first half of the plurality of windings and a second half of the plurality of windings form reverse coupling; and a second polarity terminal of an output dc side of each of said LLC circuits is connected to a second terminal of one of said windings. The current sharing realizes the reverse coupling of the secondary output inductor so as to realize negative feedback of the output current. The topological circuit can realize the current sharing of a plurality of paths of LLC with parallel input and parallel output. This topology, however, requires an output coupling inductance, adding to the complexity, cost and bulk of the circuit.
The invention with publication number CN102013806A discloses a DC/DC converter suitable for high-voltage input and high-power output, which comprises an input voltage division circuit formed by connecting two input voltage division capacitors in series, a first resonant converter, a second resonant converter and an output filter capacitor shared by the two resonant converters, wherein the first resonant converter and the second resonant converter adopt LLC series resonant circuits; two ends of the first input voltage-dividing capacitor are connected with the input end of the first resonant converter, and the output end of the first resonant converter is connected with the output filter capacitor; and two ends of the second input voltage-dividing capacitor are connected with the input end of the second resonant converter, and the output end of the second resonant converter is connected with the output filter capacitor. The invention can effectively reduce the voltage grade of the switch tube, reduce the cost and the switching loss, can effectively realize the static and dynamic current sharing performance between the two resonant converters, and improves the reliability. The two LLC inputs are respectively connected with a capacitor with the same capacitance value in parallel, the two capacitors are connected in series to realize the dynamic balance of the voltages at two ends of the capacitor, and the output currents are the same, so that the current-sharing and power-sharing of the two LLC can be realized.
Publication No. CN205212708U) discloses an LLC resonant converter circuit, which includes: a rectifier bridge; the output ends of the plurality of resonant converter units are connected in series and then connected with the input end of the rectifier bridge, so that the output of each resonant converter unit realizes current sharing. The LLC resonant converter circuit can solve the problem of non-uniform current of the LLC parallel resonant converter circuit, does not need to increase excessive semiconductor components, can reduce the volume and height of magnetic components, and improves the power density of the converter. The utility model discloses a flow equalizing mode realizes flow equalizing of output current through the series connection of output multichannel. But the multi-path still keeps the same frequency control, so the hardware characteristics are not consistent, and the brought difference can be reflected on the output voltage of each path. Therefore, the power of each path is still different, and the input current of each path at the input end is also uneven, so that the fundamental problem cannot be solved.
[ summary of the invention ]
The invention aims to provide a current-sharing adjusting method of a staggered parallel LLC circuit, which can realize current-sharing control on LLC circuits in different parallel connection modes.
In order to solve the technical problems, the invention adopts the technical scheme that the current-sharing adjusting method of the interleaved parallel LLC circuit comprises a plurality of LLC branches which are interleaved and connected in parallel, and the current difference value or the voltage difference value of each LLC branch is detected in real time to obtain an error factor e; and according to the error factor e, the duty ratio D of each LLC branch is adjusted through negative feedback, the gain of each LLC branch is changed, and the current-sharing adjustment of the interleaved parallel LLC circuits is realized.
According to the current-sharing adjusting method, for LLC circuits with parallel input and parallel output, an error factor e is obtained by detecting the input current or the output current of each LLC branch; for LLC circuits with serial input and parallel output, an error factor e is obtained by detecting input voltage or output current of each LLC branch; and for the LLC circuits with input parallel connection and output series connection, an error factor e is obtained by detecting the input current or the output voltage of each LLC branch.
According to the current-sharing regulation method, for the LLC circuits with parallel input and parallel output, when the LLC branches are N, the error of any LLC branchDifference factor
Figure BDA0001592955020000031
(i is 1 to N, i is an integer); i is input current of an LLC branch resonant cavity or output current of an LLC branch; for LLC circuits with serial input and parallel output, when the LLC branches are N, the error factor of any LLC branch
Figure BDA0001592955020000041
Or
Figure BDA0001592955020000042
(i is 1 to N, i is an integer); v is the input voltage of the LLC branch resonant cavity, and I is the output current of the LLC branch; for LLC circuits with parallel input and series output, when the LLC branches are N, the error factor of any LLC branch
Figure BDA0001592955020000043
Or(i is 1 to N, i is an integer); i is the input current of the resonant cavity of the LLC branch, and V is the output voltage of the LLC branch.
In the current sharing adjustment method, the duty ratio Di (n) (Di (n-1) -Di (n)) of any LLC branch is the last duty ratio of the LLC branch; the current flow equalizing adjustment factor di (n) of the LLC branch is obtained through digital PI calculation, and di (n) equals di (n-1) + Kp × ei (n) + Ki × ei (n); wherein di (n-1) is the last current-sharing adjustment factor of the LLC branch, Kp is the proportional coefficient of the PI controller, Ki is the integral coefficient of the PI controller, and ei is the error factor of the LLC branch.
In the above current-sharing regulation method, before calculating the current-sharing regulation factor di (n) of the LLC branch, the amplitude limit of the error factor is first determined, and if ei is less than Emin, ei is made 0, Emin being the error factor limit; after the amplitude limit of the error factor is determined, it is determined whether the power pi (n) of each LLC branch exceeds the power amplitude limit, and if not, let di (n) be 0.
The method and the device can obtain the adjustment quantity of the duty ratio by detecting the unequal flow difference value of each LLC branch in real time and calculating, and can realize the equal flow control of LLC circuits in different parallel connection modes.
[ description of the drawings ]
The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.
Fig. 1 is a graph of LLC voltage gain in a prior art FM frequency modulation mode.
Fig. 2 is an LLC voltage gain diagram in the PM duty cycle mode according to the embodiment of the present invention.
Fig. 3 is a circuit diagram of an input parallel and output parallel LLC circuit in embodiment 1 of the present invention.
Fig. 4 is a circuit diagram of an LLC circuit with serial input and parallel output in embodiment 2 of the present invention.
Fig. 5 is a circuit diagram of an LLC circuit with parallel input and series output in embodiment 3 of the present invention.
Fig. 6 is a control flow chart of two-way duty cycle current sharing regulation according to the embodiment of the present invention.
Fig. 7 is a waveform diagram of two resonant currents and duty ratios before current sharing regulation in embodiment 1 of the present invention.
Fig. 8 is a waveform diagram of two resonant currents and a duty ratio after current sharing adjustment in embodiment 1 of the present invention.
Fig. 9 is a control flow chart of multi-channel duty cycle current sharing regulation according to an embodiment of the present invention.
[ detailed description of the invention ]
In order to realize high power density of staggered parallel connection, the invention provides a current sharing control method suitable for circuits with three LLC parallel connection modes. The interleaved LLC circuits in parallel connection can meet high-power-density output, parallel multi-path current sharing is realized by controlling modulation, and power sharing and topological reliability are guaranteed.
In an LLC topology circuit, the adjustment of the input and output gain is usually realized by adjusting the resonant frequency of the resonant cavity, i.e. FM adjustment method. The voltage gain is as follows:
Figure BDA0001592955020000051
wherein the content of the first and second substances,
Figure BDA0001592955020000052
for the ratio of the excitation inductance to the resonance inductance,
Figure BDA0001592955020000053
in order to be at the resonant frequency,
Figure BDA0001592955020000054
quality factor, LmFor exciting inductance, LrIs a resonant inductor, CrIs a resonant capacitor, RrIs a load resistor. The gain curve with the switching frequency f can be obtained from different values of K, Q as shown in fig. 1,the circuit is usually designed to operate at fr＜f＜fmaxThe gain monotone section of (1).
However, in order to realize the minimum output current ripple, the two parallel interleaving circuits need to keep the switching frequencies of the two parallel interleaving circuits consistent. Under the condition, in order to overcome the non-uniform current caused by the difference of the hardware characteristics of the two parallel circuits, two gain adjustment factors need to be added. In an LLC circuit, operating at a resonant frequency point, and with a fixed value of K, Q, the duty cycle voltage gain relationship is approximately:
where D is the duty cycle. The voltage gain curve can be obtained as shown in fig. 2. It can be known that when the interval of duty ratio is Dmin < D < Dmax < 0.5, the voltage gain is monotonous.
The invention solves the technical scheme adopted by two paths of interleaved parallel LLC current sharing and comprises the following steps: and detecting error factors e of the two interleaved parallel LLC circuits in real time, and then adjusting the duty ratio D of the two parallel LLC circuits through negative feedback to change the gain of the two parallel LLC circuits. The current sharing adjustment can be realized for different parallel connection modes of two paths of interleaved parallel LLC. The two LLC parallel modes mainly comprise input parallel output parallel connection, input series output parallel connection and input parallel output series connection. The input parallel output parallel circuit can obtain an error factor e by detecting the difference value of two paths of input currents or two paths of output currents; the input series output parallel circuit can obtain an error factor e by detecting the difference value of two paths of input voltages or the difference value of two paths of output currents; the input parallel output series circuit can obtain an error factor e by detecting the difference value of two paths of input currents or the difference value of two paths of output voltages. And the error factor e respectively obtains two negative feedback duty ratio regulating quantities through the result of the digital PI controller. The voltage gain is adjusted through the difference of the duty ratios of the two paths, so that the two paths of current sharing are realized.
Embodiment 1 of the present invention is shown in fig. 3, which shows an input parallel and output parallel LLC circuit. 11. 12 are two LLC circuits, the inputs of which are connected in parallel, and the outputs of which are connected in parallel and then connected with a load. In 11, Q1 and Q2 are switching tubes of a half bridge LLC, and Lr1 and Cr1 are resonant inductors and capacitors. T1 is a transformer, and its secondary winding is connected with full-bridge rectifiers D1, D2, D3 and D4. Co1 is the output filter capacitance, Ro1 is the output load. ir1 is the first input cavity current, and io1 is the first output current. The circuit structure and composition of 12 is the same as 11. Two ways of LLC circuits realize the staggered output through the same-frequency phase-staggered control, and the output ripple current is small. Two paths are staggered and staggered by pi/2. The two paths of current sharing error factors can be e-ir 1-ir2 or e-io 1-io 2. In this embodiment, e ═ ir1 to ir2 are taken. The specific control method for the current sharing factor is shown in fig. 6. Firstly, the amplitude of the error factor is determined, and if e < Emin, e is made to be 0. Emin is an error factor limit value, and when the error factor value is within the limit value, no further adjustment is performed, so that over-adjustment is prevented. In this embodiment, Emin is 3% of the rated output current. The error factor is calculated by digital PI to obtain the current sharing regulating factor d (n) ═ d (n-1) + Kp × e (n) + Ki × e (n). Wherein d (n) is the current-sharing adjustment factor, and d (n-1) is the last current-sharing adjustment factor. Kp and Ki are respectively proportional coefficient and integral coefficient of the PI controller. After the current-sharing adjustment factor d (n) is subjected to amplitude limiting processing (the absolute value of the current-sharing adjustment factor d (n) is smaller than an amplitude limiting value Dmax), whether the first two-way power P1(n) and the first two-way power P2(n) exceed a single-way power amplitude limiting value PLimit is judged, and if the first two-way power P1(n) and the first two-way power P2(n) do not exceed the single-way power amplitude limiting value. In this embodiment PLimit takes 30% of the rated total output power of the single circuit. Respectively obtaining a first two-way duty ratio as follows through a current-sharing adjusting factor d (n): d1(n) ═ D1(n-1) -D (n), D2(n) ═ D2(n-1) + D (n). And D1(n) and D2(n) are limited to be not more than 0-0.5, and Ddead time is obtained. Fig. 7 shows waveforms of two resonant currents and duty ratios before current sharing regulation in this embodiment, where ir1 is 1A greater than ir2 under the condition of the same switching frequency and duty ratio. Fig. 8 shows waveforms of two resonant currents and duty ratios after current sharing adjustment in this embodiment, where the switching frequencies are the same, D1 is 0.4176, D2 is 0.4569, and ir1 is 10.075A, ir1 is 9.891A.
Embodiment 2 of the present invention is shown in fig. 4, which shows an input series and output parallel LLC circuit. 13. 14 are two LLC circuits, the inputs of which are connected to input capacitors Cin1 and Cin2, respectively. The voltages at two ends of the input capacitors Cin1 and Cin2 are respectively Vin1 and Vin2, and Cin1 and Cin2 are connected in series. The outputs of the two LLC circuits are connected in parallel with an output capacitor Co1 and a load Ro1. the circuit structures and the compositions of the two LLC circuits 13 and 14 are the same as those of 11. Two ways of LLC circuits realize the staggered output through the same-frequency phase-staggered control, and the output ripple current is small. Two paths are staggered and staggered by pi/2. The two paths of current sharing error factors can be e-Vin 1-Vin2 or e-io 1-io 2. In this embodiment, let e be Vin1-Vin 2. The specific control method for the current sharing factor is shown in fig. 6. And after the current sharing error factor is calculated, a current sharing adjusting factor is obtained and respectively adjusts the duty ratio of the first circuit and the second circuit to realize current sharing.
Embodiment 3 of the present invention is shown in fig. 5, which shows an input parallel output series LLC circuit. 15. 16 are two LLC circuits, the outputs of which are connected to output capacitors Co1 and Co2, respectively. The voltages at two ends of the output capacitors Co1 and Co2 are Vo1 and Vo2 respectively, and Co1 and Co2 are connected in series and then connected with a load Ro1. The two LLC circuit inputs are connected in parallel, and the circuit structures and the compositions of the two LLC circuits 15 and 16 are the same as those of the LLC circuit 11. Two ways of LLC circuits realize the staggered output through the same-frequency phase-staggered control, and the output ripple current is small. Two paths are staggered and staggered by pi/2. The two paths of current sharing error factors can be e-Vo 1-Vo2 or e-ir 1-ir 2. In this embodiment, take e-Vo 1-Vo 2. The specific control method for the current sharing factor is shown in fig. 6. And after the current sharing error factor is calculated, a current sharing adjusting factor is obtained and respectively adjusts the duty ratio of the first circuit and the second circuit to realize current sharing.
In the above three embodiments of the present invention, the two paths of staggered phases pi/2 are staggered, but other staggered values are also possible, and only the staggered phase pi/2 can optimally realize small output current ripple.
The digital PI controller in the three embodiments of the present invention may also make the scaling factor Kp equal to 0, leaving only the integral adjustment.
In three embodiments of the present invention, PLimit takes 30% of the rated total output power of the single circuit, and can also take 0%, 100% or other rated total output power of the single circuit.
The three embodiments of the invention are all applied to the parallel connection of two LLC circuits, and the invention can also be applied to the staggered parallel current sharing in a plurality of LLC parallel circuits. In the N-channel LLC parallel circuit, the mutual phase error value is pi/N.
For LLC circuits with parallel input and parallel output, when the LLC branches are N, the error factor of any LLC branch
Figure BDA0001592955020000081
(i is 1 to N, i is an integer); i is input current of an LLC branch resonant cavity or output current of an LLC branch; for LLC circuits with serial input and parallel output, when the LLC branches are N, the error factor of any LLC branch
Figure BDA0001592955020000082
Or
Figure BDA0001592955020000083
(i is 1 to N, i is an integer); v is the input voltage of the LLC branch resonant cavity, and I is the output current of the LLC branch; for LLC circuits with parallel input and series output, when the LLC branches are N, the error factor of any LLC branchOr
Figure BDA0001592955020000092
(i is 1 to N, i is an integer); i is the input current of the resonant cavity of the LLC branch, and V is the output voltage of the LLC branch.
The duty ratio Di (n) of any LLC branch is Di (n-1) -Di (n), and Di (n-1) is the last duty ratio of the LLC branch; the current flow equalizing adjustment factor di (n) of the LLC branch is obtained through digital PI calculation, and di (n) equals di (n-1) + Kp × ei (n) + Ki × ei (n); wherein di (n-1) is the last current-sharing adjustment factor of the LLC branch, Kp is the proportional coefficient of the PI controller, Ki is the integral coefficient of the PI controller, and ei is the error factor of the LLC branch.
The control method for the current-sharing regulation of the multi-path LLC parallel circuit is slightly different from the current-sharing control method of the two-path LLC parallel circuit. Each LLC circuit needs to perform the current sharing adjustment in fig. 9. Path i error factor in fig. 9
Figure BDA0001592955020000093
Pi (n) is the current power of the LLC branch. And the Nth error factor is calculated to obtain a current sharing regulation factor di (N) and a duty ratio Di (N) ═ Di (N) ((N) — di (N)). And each path is respectively calculated and adjusted to realize N paths of current sharing.
The embodiment of the invention has the advantages that the output current ripple is small and the filter capacitance is small by using the same frequency interleaving in the parallel LLC circuit; by detecting the difference value of the two paths of unequal flows in real time and carrying out digital PI operation, the adjustment quantity of the duty ratio is obtained, and the equal flow control of different parallel LLC circuits can be realized.
While embodiments of the present invention have been shown and described above, it should be understood that the above embodiments are exemplary and should not be taken as limiting the invention. Variations, modifications, substitutions and alterations of the above-described embodiments may occur to those of ordinary skill in the art without departing from the scope of the present invention.

Claims (2)

1. A current sharing regulation method for interleaved LLC circuits in parallel comprises a plurality of LLC branches in interleaved parallel, and is characterized in that the current difference or electricity of each LLC branch is detected in real timeObtaining an error factor e by a differential pressure value; according to the error factor e, the duty ratio D of each LLC branch is adjusted through negative feedback, the gain of each LLC branch is changed, and the current-sharing adjustment of the interleaved parallel LLC circuits is realized; for LLC circuits with parallel input and parallel output, an error factor e is obtained by detecting the input current or the output current of each LLC branch; for LLC circuits with serial input and parallel output, an error factor e is obtained by detecting input voltage or output current of each LLC branch; for LLC circuits which are input in parallel and output in series, an error factor e is obtained by detecting the input current or the output voltage of each LLC branch; for LLC circuits with parallel input and parallel output, when the LLC branches are N, the error factor of any LLC branch
Figure FDA0002200685690000011
(I is 1-N, I is an integer), and I is input current of the LLC branch resonant cavity or output current of the LLC branch; for LLC circuits with serial input and parallel output, when the LLC branches are N, the error factor of any LLC branch
Figure FDA0002200685690000012
Or
Figure FDA0002200685690000013
(I is 1-N, I is an integer), V is the input voltage of the LLC branch resonant cavity, and I is the output current of the LLC branch; for LLC circuits with parallel input and series output, when the LLC branches are N, the error factor of any LLC branch
Figure FDA0002200685690000014
Or
Figure FDA0002200685690000015
(I is 1-N, I is an integer), I is the input current of the LLC branch resonant cavity, and V is the output voltage of the LLC branch; the duty ratio Di (n) of any LLC branch is Di (n-1) + Di (n), and Di (n-1) is the last duty ratio of the LLC branch; the current flow equalizing adjustment factor di (n) of the LLC branch is obtained through digital PI calculationDi (n) ═ di (n-1) + Kp × ei (n) + Ki × (n) dt; wherein di (n-1) is the last current-sharing adjustment factor of the LLC branch, Kp is the proportional coefficient of the PI controller, Ki is the integral coefficient of the PI controller, and ei is the error factor of the LLC branch.
2. The method according to claim 1, wherein before calculating the current-sharing adjustment factor di (n) of the LLC branch, the amplitude-limiting determination is first performed on the error factor, and if ei < Emin, ei is made to be 0, and Emin is the error factor limit; after the amplitude limit of the error factor is determined, it is determined whether the power pi (n) of each LLC branch exceeds the power amplitude limit, and if not, let di (n) be 0.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112217274A (en) * 2020-09-03 2021-01-12 深圳市领灿科技有限公司 Double-backup power circuit

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111587526A (en) * 2018-12-17 2020-08-25 富士电机株式会社 DC-DC converter device
CN109861538A (en) * 2019-03-27 2019-06-07 深圳市安健科技股份有限公司 A kind of automatic current equalizing circuit in shunt transformer primary side series connection common mode inductance
CN110677032A (en) * 2019-10-21 2020-01-10 宁波奥克斯电气股份有限公司 Current sharing control method and device for staggered parallel PFC circuit and air conditioner
CN111262441A (en) * 2020-01-16 2020-06-09 湖南晟和电源科技有限公司 Power supply circuit and power supply
CN111934555A (en) * 2020-08-18 2020-11-13 国网湖南省电力有限公司 LLC resonant circuit, control method and LLC resonant converter
CN112117912B (en) * 2020-10-13 2022-10-18 上海宇帆电气有限公司 Power converter and control method thereof
CN113098278B (en) * 2021-04-01 2023-03-03 武汉麦格米特电气有限公司 Current-sharing adjusting method and circuit for interleaved LLC circuit in parallel and resonant converter
CN113992022B (en) * 2021-10-20 2023-09-29 华中科技大学 Multi-phase staggered parallel LLC converter optimal control method and device
CN114844365A (en) * 2022-05-18 2022-08-02 厦门大学 IPOS type high-transformation-ratio soft switching converter with coupling inductor and switching capacitor

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6215290B1 (en) * 1999-11-15 2001-04-10 Semtech Corporation Multi-phase and multi-module power supplies with balanced current between phases and modules
CN101552557B (en) * 2008-04-02 2012-03-07 台达电子工业股份有限公司 Parallel-connected resonance converter circuit and control method thereof
CN102769385B (en) * 2012-05-28 2014-10-08 华为技术有限公司 Current sharing control method, device and system for multi-phase parallel system
CN104242421A (en) * 2013-06-20 2014-12-24 中国北车股份有限公司 Railway vehicle charger system and railway vehicle
CN104935177B (en) * 2015-07-14 2017-05-24 山东大学 Current-sharing control system and control method used for multi-module parallel combination DC-DC converter
CN106357109A (en) * 2016-11-14 2017-01-25 东南大学 Control method for input and voltage equalizing of ISOP system based on output current feedback
CN106849682B (en) * 2017-04-18 2019-06-18 中国石油大学(华东) A kind of three-phase crisscross parallel LLC resonant converter pressure stabilizing current-sharing control method
CN107592016A (en) * 2017-09-11 2018-01-16 珠海格力电器股份有限公司 The two-way DC/DC converters of crisscross parallel and its current equalizer, current equalizing method

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112217274A (en) * 2020-09-03 2021-01-12 深圳市领灿科技有限公司 Double-backup power circuit

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