CN114583951A - High-gain converter for photovoltaic direct current module and control method thereof - Google Patents
High-gain converter for photovoltaic direct current module and control method thereof Download PDFInfo
- Publication number
- CN114583951A CN114583951A CN202210237775.5A CN202210237775A CN114583951A CN 114583951 A CN114583951 A CN 114583951A CN 202210237775 A CN202210237775 A CN 202210237775A CN 114583951 A CN114583951 A CN 114583951A
- Authority
- CN
- China
- Prior art keywords
- boost
- voltage
- inductor
- capacitor
- switch tube
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Images
Classifications
-
- 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
- H02M3/02—Conversion of dc power input into dc power output without intermediate conversion into ac
- H02M3/04—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters
- H02M3/10—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M3/145—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
- H02M3/155—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M3/156—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of output voltage or current, e.g. switching regulators
- H02M3/158—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of output voltage or current, e.g. switching regulators including plural semiconductor devices as final control devices for a single load
-
- 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
- H02M1/00—Details of apparatus for conversion
- H02M1/08—Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters
- H02M1/088—Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters for the simultaneous control of series or parallel connected semiconductor devices
-
- 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
- H02M1/00—Details of apparatus for conversion
- H02M1/38—Means for preventing simultaneous conduction of switches
-
- 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
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/50—Photovoltaic [PV] energy
- Y02E10/56—Power conversion systems, e.g. maximum power point trackers
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Dc-Dc Converters (AREA)
Abstract
The invention belongs to the technical field of DC-DC boost converters, and discloses a high-gain converter for a photovoltaic direct current module and a control method thereof, wherein the converter can change the number of boost units in the boost module according to the actual voltage range of a photovoltaic cell panel and a direct current bus, thereby flexibly changing the boost capability and having strong expandability; only two switching tubes form a half-bridge structure, a low-cost bootstrap driver can be adopted, and the structure is simple and easy to realize; the inductance values of the rear-stage inductor and the boosting inductors in all the boosting units are small, so that the size is small, and the power density is high; the voltage stress of all power tubes is the same and is far smaller than the output voltage, and low-voltage-resistant devices can be adopted, so that the system cost and the power loss are reduced; all power tubes realize soft switching, so that the system efficiency is higher; the input and the output are connected to the same ground, so that the sampling circuit is simple in structure, and the photovoltaic direct current module can pass the EMI related test requirements more easily.
Description
Technical Field
The invention belongs to the technical field of DC-DC boost converters, and particularly relates to a high-gain converter for a photovoltaic direct-current module and a control method thereof.
Background
The photovoltaic direct current module can effectively solve the problem that the solar energy utilization rate of the string type photovoltaic power generation system is low under the condition of partial shadow shielding. The output voltage of the photovoltaic cell panel is low, the variation range is wide, and the power generation efficiency or the service life is closely related to the output current ripple rate, so that the photovoltaic direct current module needs to adopt a high-gain converter with continuous input current as a main circuit and then can be integrated into a public power grid through a traditional voltage source type grid-connected inverter. High gain converters can be classified into two types, including a transformer (including coupled inductors) type and a transformer-less type. Compared with the former, the transformerless high-gain converter has the advantages of small volume, low cost, high efficiency and the like without a high-frequency transformer. Moreover, the current leakage current suppression strategy of the non-isolated grid-connected inverter is mature day by day, and the electrical safety problem is well solved. Therefore, it is more advantageous to use the transformerless high-gain converter as the main circuit of the photovoltaic dc module.
Various scholars introduce Boost networks such as a switch inductor, a switch capacitor, a quasi-Z source or a Boost and the like into a traditional Boost converter respectively to obtain various transformer-free high-gain Boost schemes. Most of the schemes can realize single-stage conversion of energy, the conversion efficiency is high, but the voltage gain is usually not more than twice of that of the traditional Boost converter. To this end, the scholars further propose high gain schemes based on boost network expansion. Although the scheme of adopting the extended boost network can obviously improve the boost capability, the volume and the weight of the converter are obviously increased due to the increase of the number of the energy storage elements. The switching frequency of the converter is improved, the volume and the weight of the energy storage element can be effectively reduced, the power density is improved, the switching loss of the power tube is also increased rapidly, and the conversion efficiency is reduced seriously. The introduction of soft switching technology can effectively solve these problems. To this end, researchers have further proposed many ZVS high-gain converters based on boost network extensions. However, these topologies have the following problems in common: (1) the number of diodes is large, and the structure is complex; (2) part of power tubes still work in a hard switching state, so that the efficiency is difficult to further improve; (3) the power tube has higher voltage stress, and a high-voltage-resistant semiconductor device is required, so that the on-state loss is larger, and the cost is higher; (4) there is a loss of duty cycle.
Disclosure of Invention
In view of this, the present invention provides a high-gain converter for a photovoltaic dc module and a control method thereof, which have the advantages of low Voltage stress, small number of power tubes, Zero Voltage Switching (ZVS) of Switching tubes, Zero current turn-off of diodes, high conversion efficiency, no duty cycle loss, simple control, low cost, and the like, and can flexibly adjust the number of boost units in a boost module according to the boost capability requirements under different application environments to change the Voltage gain of the converter.
In order to achieve the purpose, the technical scheme provided by the invention is as follows:
a high-gain converter for a photovoltaic direct current module comprises a basic module and a boosting module;
the boost module includes n boost units, and each boost unit includes: boost diode DaFilter capacitor CaAnd an auxiliary capacitor CbBoost inductor La;
The internal connection mode of the boosting unit is as follows: the boost diode DaAnd the boost inductor LaFirst terminal of, said filter capacitor CaThe positive electrodes of the two electrodes are connected; the boost inductor LaAnd the second terminal of the auxiliary capacitor CbThe positive electrodes of the two electrodes are connected;
the boost pressureThe connection mode between the units is as follows: boost diode D in the latter boost unitaAnode and auxiliary capacitor C in the previous booster unitbPositive pole of (1), boost inductor L in the previous boost unitaAre connected with each other; auxiliary capacitor C of n boosting unitsbThe negative electrode of (a) is uniformly crossed with the point b; the filter capacitors C of the n boosting unitsaThe negative electrode of (a) is crossed with the point a;
the base module includes: photovoltaic cell panel UinAn input filter capacitor CinAn input inductor LinA rear stage inductor LmA first switch tube S1A second switch tube S2A first capacitor C1A second capacitor C2And an output diode DoAn output filter capacitor CoA load R;
the connection mode of the basic module and the boosting module is as follows: the photovoltaic cell panel UinAnd the input inductance LinFirst terminal of, said input filter capacitance CinThe positive electrodes of the two electrodes are connected; the input inductance LinAnd the second end of the first switch tube S1Drain electrode of (1), the second switching tube S2Source electrode of, the second capacitor C2The negative pole of the voltage boosting module is connected with the point b of the voltage boosting module; the second switch tube S2And the post-stage inductor LmFirst terminal of, said first capacitor C1The positive electrodes of the two electrodes are connected; the back stage inductor LmAnd the second terminal of the second capacitor C2Positive pole of (2), boost diode D of the first boost unit in the boost moduleaThe anodes of the anode groups are connected; the output diode DoAnd the boost inductance L of the last boost unit in the boost moduleaAnd an auxiliary capacitor CbThe positive electrodes of the two electrodes are connected; the output diode DoAnd the output filter capacitor CoThe positive electrode of (a) is connected with the first end of the load R; a second terminal of the load R and the output filter capacitor CoThe negative pole of (1), the point a of the boosting module, the first switch tube S1Source electrode of, said input filter capacitor CinThe negative electrode of,The first capacitor C1And the photovoltaic cell panel UinThe negative electrodes are connected;
the input inductance LinThe inductance value of (a) satisfies:
in the above formula, Deff=D+Td/Ts,DeffFor an effective duty cycle, D is a first switching tube S1Duty cycle of the drive signal of (1), TdIs a first switch tube S1And a second switch tube S2With a dead time of the drive signal, TsIs a first switch tube S1And a second switch tube S2Period of the drive signal of (1), LinFor input of an inductor LinInductance value of, Δ ILinIs an input inductance LinCurrent peak-to-peak value of, UinFor the photovoltaic cell panel voltage, fsDelta% is the input inductance L for the switching frequencyinMaximum permissible current ripple and input inductance LinA percentage of maximum average current; p iso,maxIs the maximum output power;
the back stage inductor LmAnd a boost inductor L in the boost unitaThe inductance value of (a) satisfies:
in the above formula, LmIs a post-stage inductor LmInductance value of, LaIs a boost inductor LaInductance value of, UoIs the output voltage; n is the number of booster cells.
The invention also provides a control method of the high-gain converter for the photovoltaic direct-current module, which specifically comprises the following steps:
sampling the voltage and current of the photovoltaic cell panel to obtain a voltage sampling value u of the photovoltaic cell panelin,fCurrent sample value iin,fGenerating photovoltaic cell panel electricity through MPPT calculationPressure reference value uin,refSampling the voltage u of the photovoltaic cell panelin,fWith the voltage reference value u of the photovoltaic cell panelin,refComparing to obtain an error signal uin,f-uin,ref;
The error signal is sent to a voltage controller to obtain an adjusting signal ur;
The regulating signal urWith a unipolar triangular carrier ucCrossing to generate a first switch tube S1PWM drive signal ugs1;
The first switch tube S1PWM drive signal ugs1Negation is carried out to obtain a second switch tube S2PWM drive signal ugs2。
Further, the ideal voltage gain of the high-gain converter for the photovoltaic DC module is [1+ (1+ n) Deff]/(1-Deff) By adjusting the number n of the boosting units, the voltage gain can be flexibly adjusted to enable the boosting units to work under a proper duty ratio D so as to meet boosting requirements on different occasions.
Further, in the high-gain converter for the photovoltaic dc module, the first switch tube S1A second switch tube S2And an output diode DoAnd a boost diode D in the boost unitaAll bear the same voltage stress and are [ (n +1) Uin+Uo]V (n +2), much smaller than the output voltage Uo。
The invention also provides a photovoltaic direct current module which comprises the high-gain converter for the photovoltaic direct current module.
Compared with the prior art, the high-gain converter for the photovoltaic direct-current module can change the number of the boosting units in the boosting module according to the actual voltage ranges of the photovoltaic cell panel and the direct-current bus, so that the boosting capacity is flexibly changed, and the high-gain converter has strong expandability; only two switching tubes are arranged, and the two switching tubes form a half-bridge structure, so that various bootstrap drivers with low price and mature technology can be adopted, and the structure is simple and easy to realize; and a back-stage inductor LmAnd all boost unitsVoltage boosting inductor L in elementaThe inductance value of the photovoltaic direct current module is small, so that the photovoltaic direct current module is small in size and high in power density; the voltage stress of all the switching tubes and the voltage stress of all the diodes are the same and are far smaller than the output voltage, and low-voltage-resistant devices can be adopted, so that the system cost and the power loss are reduced; ZVS switching-on is realized for all the switching tubes, all the diodes can be approximately naturally turned off under the heavy load condition, and can be completely naturally turned off under the light load condition, so that the system efficiency of the photovoltaic direct current module is higher; the input and the output are connected to the same ground, so that the sampling circuit is simple in structure, and the photovoltaic direct current module can pass the EMI related test requirements more easily.
Drawings
Fig. 1 is a schematic circuit diagram of a high-gain converter for a photovoltaic dc module according to the present invention;
FIG. 2 is a control block diagram of a high gain converter for a photovoltaic DC module provided by the present invention;
fig. 3 is a schematic circuit structure diagram of an embodiment of a high-gain converter for a photovoltaic dc module according to the present invention;
FIG. 4 is an equivalent circuit diagram of 4 operating modes of the converter shown in FIG. 3 during a switching cycle;
FIG. 5 shows the converter of FIG. 3 during a switching period TsThe main working waveform diagram in the inner part;
FIG. 6 is an average current equivalent circuit diagram of the converter of FIG. 3;
FIG. 7 is a schematic diagram of a circuit configuration of the converter shown in FIG. 3 including 1 boost unit;
FIG. 8 is an experimental waveform of steady state characteristics of the converter shown in FIG. 3 with 1 boost unit;
fig. 9 is a simulated waveform diagram of load switching when the converter shown in fig. 3 includes 1 boost unit.
Detailed Description
The technical solutions in the embodiments of the present application will be described clearly and completely with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
As shown in fig. 1, the present invention provides a high gain converter for a photovoltaic dc module, comprising a base module and a boost module; the boost module includes n boost units, and each boost unit includes: boost diode DaFilter capacitor CaAnd an auxiliary capacitor CbBoost inductor La(ii) a The internal connection mode of the boosting unit is as follows: boost diode DaCathode and boost inductor LaFirst terminal of (1), filter capacitor CaThe positive electrodes of the two electrodes are connected; boost inductor LaSecond terminal and auxiliary capacitor CbThe positive electrodes of the two electrodes are connected;
the connection mode between the boosting units is as follows: boost diode D in the latter boost unitaAnode and auxiliary capacitor C in the previous booster unitbPositive pole of (1), boost inductor L in the previous boost unitaAre connected with each other; auxiliary capacitor C of n boosting unitsbAll the negative electrodes are intersected at a point b; the filter capacitors C of the n boosting unitsaThe negative electrode of (a) is crossed with the point a;
the base module includes: photovoltaic cell panel UinAn input filter capacitor CinAn input inductor LinA rear stage inductor LmA first switch tube S1A second switch tube S2A first capacitor C1A second capacitor C2And an output diode DoAn output filter capacitor CoA load R;
the connection mode of the basic module and the boosting module is as follows: photovoltaic cell panel UinPositive pole and input inductance LinFirst terminal, input filter capacitor CinThe positive electrodes of the two electrodes are connected; input inductance LinSecond terminal and first switch tube S1Drain electrode of the first switching tube S2Source electrode of the first capacitor C2The negative pole of the voltage boosting module is connected with the point b of the voltage boosting module; a second switch tube S2Drain electrode of and post-stage inductor LmFirst terminal of (1), first capacitor C1The positive electrodes of the two electrodes are connected; rear stageInductor LmSecond terminal and second capacitor C2Anode of the boosting module, and the boosting diode D of the first boosting unit in the boosting moduleaThe anodes of the anode groups are connected; output diode DoAnd the boost inductor L of the last boost unit in the boost moduleaSecond terminal and auxiliary capacitance CbThe positive electrodes of the two electrodes are connected; output diode DoCathode and output filter capacitor CoThe anode of the load R is connected with the first end of the load R; the second end of the load R and the output filter capacitor CoNegative pole, a point of the boost module, the first switch tube S1Source electrode, input filter capacitor CinNegative electrode of (1), first capacitor C1Negative pole and photovoltaic cell board UinAre connected with each other.
As shown in fig. 2, the control method of the high-gain converter for the photovoltaic dc module includes: to photovoltaic cell panel UinThe voltage and the current are sampled to obtain a voltage sampling value u of the photovoltaic cell panelin,fCurrent sample value iin,fAnd generating a photovoltaic cell panel voltage reference value u through MPPT calculationin,refSampling the voltage of the photovoltaic cell panel uin,fWith reference value u of the voltage of the photovoltaic cell panelin,refComparing to obtain an error signal uin,f-uin,ref(ii) a Error signal uin,f-uin,refSending to a voltage controller to obtain a regulation signal ur(ii) a Regulating signal urWith a unipolar triangular carrier ucCrossing to generate a first switch tube S1PWM drive signal ugs1(ii) a A first switch tube S1PWM drive signal ugs1Negation is carried out to obtain a second switch tube S2PWM drive signal ugs2。
As shown in fig. 3, an embodiment of the present invention provides a circuit structure diagram of an embodied high-gain converter, where the converter includes: 1 basic module and 1 boosting module; wherein: the boosting module comprises n boosting units; the components and the internal connection forms of the n boosting units are the same, and the ith boosting unit is taken as an example for explanation and comprises the following components: ith boost diode DaiIth filter capacitor CaiThe ith auxiliary capacitor CbiIth boost inductorLaiWherein the ith boost diode DaiCathode and ith boost inductor LaiFirst terminal of (1), ith filter capacitor CaiIs connected with the positive pole of the ith boost inductor LaiSecond terminal and ith auxiliary capacitor CbiThe positive electrodes of the two electrodes are connected;
the connection form between the individual booster cells is as follows, 1<i is not more than n: boost diode D in ith boost unitaiAnd the auxiliary capacitor C in the (i-1) th booster unitb(i-1)Positive electrode of (1) th boosting unit, and boosting inductor L in (i-1) th boosting unita(i-1)Are connected with each other; the cathodes of the auxiliary capacitors of the n boosting units in the boosting module are intersected with a point b; the cathodes of the filter capacitors of n boosting units in the boosting module are intersected with a point a;
the base module includes: photovoltaic cell panel UinAn input filter capacitor CinAn input inductor LinA rear stage inductor LmA first switch tube S1A second switch tube S2A first capacitor C1A second capacitor C2And an output diode DoAn output filter capacitor CoA load R;
the connection mode of the basic module and the boosting module is as follows: photovoltaic cell panel UinPositive pole and input inductance LinFirst terminal, input filter capacitor CinThe positive electrodes of the two electrodes are connected; input inductance LinSecond terminal and first switch tube S1Drain electrode of the first switching tube S2Source electrode of the first capacitor C2The negative pole of the voltage boosting module is connected with the point b of the voltage boosting module; a second switch tube S2Drain electrode of (2) and back-stage inductor LmFirst terminal, first capacitor C1The positive electrodes of the two electrodes are connected; rear stage inductance LmSecond terminal and second capacitor C2Anode of the boosting module, and the boosting diode D of the 1 st boosting unit in the boosting modulea1The anodes of the anode groups are connected; output diode DoAnd the boosting inductance L of the nth boosting unit in the boosting moduleanSecond terminal and filter capacitor CanThe positive electrodes of the two electrodes are connected; output diode DoCathode and output filter capacitor CoThe anode of the load R is connected with the first end of the load R; second terminal and output of load ROutput filter capacitor CoNegative pole, a point of the boost module, the first switch tube S1Source electrode, input filter capacitor CinNegative electrode of (1), first capacitor C1Negative pole and photovoltaic cell board UinAre connected with each other.
The operation of the high gain converter shown in fig. 3 is explained below. To simplify the analysis, the following assumptions were made: first switch tube S1A second switch tube S2And an output diode DoA first capacitor C1A second capacitor C2Output filter capacitor CoAn input inductor LinA rear stage inductor LmBoosting inductors, boosting diodes, filter capacitors and auxiliary capacitors in all the boosting units are ideal devices; a first capacitor C1A second capacitor C2An output filter capacitor CoThe filter capacitors and the auxiliary capacitors in all the boosting units are large enough, and voltage ripples can be ignored; photovoltaic cell panel UinThe negative end is a zero potential reference point; first switch tube S1And a second switch tube S2With a dead time of T of the drive signald(ii) a Input inductance LinCurrent i ofLinUnidirectional, continuous flow, back-stage inductor LmAnd the current of the boosting inductor in all the boosting units flows in two directions, and the current i is synthesizedLTrough i ofL,valSatisfies the following conditions: iL,val|>|iLin,val|,iLin,valFor inputting an inductive current iLinValley value of, resulting current iLIs a post-stage inductor LmThe sum of the currents of the boost inductors in all the booster cells, iL=iLm+iLa1……iL(n-1)+iLan。
Based on the above assumptions, after entering a steady state, the working process of the high-gain converter for the photovoltaic dc module according to the present invention in one switching cycle can be divided into 4 modes. The equivalent circuits of the modes are shown in fig. 4(a) to 4 (d). The main waveforms during one switching cycle are shown in fig. 5.
The following are distinguished:
t0before the moment, the first switch tube S1Body diode ofThe tube has already conducted freewheeling.
(1) Mode 1, t0~t1Stage (2): (the equivalent circuit is shown in FIG. 4 (a))
t0At the moment, the first switch tube S is switched on by zero voltage1Its body diode is naturally turned off. In this mode, the second switch tube S2Boost diode and output diode D in all boost unitsoAre all reverse biased; input inductance LinAnd a rear stage inductor LmThe boosting inductors in all the boosting units bear forward voltage; input of inductor current iLinLinearly increasing, post-stage inductance LmAnd the current of the boosting inductor in all the boosting units is linearly decreased in the reverse direction and then linearly increased in the forward direction. At this time, there are:
wherein L isinFor input of an inductor LinInductance value of, LmAnd LaiAre respectively a rear stage inductor LmAnd boost inductor L in the ith boost unitaiThe inductance value of (a); i.e. iLinFor input of an inductor LinCurrent value of iLmAnd iLaiRespectively, a rear stage inductor LmAnd boost inductor L in the ith boost unitaiThe current value of (a); u shapeC1And UC2Are respectively a first capacitor C1And a second capacitor C2The terminal voltage of (a); u shapeCai、UCbiAre respectively an ith filter capacitor CaiThe ith auxiliary capacitor Cbi1,2, … …, n.
(2) Mode 2, t1~t2Stage (2): (the equivalent circuit is shown in FIG. 4 (b))
t1At any moment, the first switch tube S is turned off1Modality 2 begins. In the first switch tube S1At the moment of turn-off, the input inductance LinA rear stage inductor LmAnd the current of the boost inductor in all the boost units flows into the node m to force the second switch tube S2The body diode of (1) conducts freewheeling; at the same time, step up two in all the step-up unitsPolar tube and output diode DoAre all forward biased; input inductance LinA rear stage inductor LmAnd all the boosting inductors in the boosting units bear reverse voltage, and the current of the boosting inductors is linearly decreased in the forward direction. At this time, there are:
(3) mode 3, t2~t3Stage (2): (the equivalent circuit is shown in FIG. 4 (c))
t2At the moment, the second switch tube S is switched on by zero voltage2With its body diode naturally turned off, mode 3 begins. In this mode, the inductor current i is inputLinContinuously decreases in a forward linear way, and then the inductor L at the later stagemAnd the current of the boosting inductor in all the boosting units is linearly increased in the reverse direction after being reduced to zero in the forward direction. The current expression is the same as that of the formula (2).
(4) Mode 4, t3~t4: (the equivalent circuit is shown in FIG. 4 (d))
t3At the moment, the second switch tube S is turned off2Modality 4 begins. Input of inductor current iLinAn inflow node m; rear stage inductance LmAnd the current of the boost inductor in all the boost units flows out of the node m and synthesizes a current iLSatisfies the following conditions: iL|>|iLinI, so the first switch tube S1The body diode of (1) conducts a freewheeling current. Input inductance LinAnd a rear stage inductor LmAnd the current expression of the boost inductor in all the booster cells is similar to that in mode 1. t is t4At the moment, the first switch tube S is switched on by zero voltage1And entering the next switching period.
Based on the above operating principle, the steady-state characteristics of the converter of the present invention are analyzed below.
According to the input inductance LinA rear stage inductor LmAnd the ith boost inductor LaiThe voltage-second balance of (a) can be obtained:
Deff=D+Td/Ts (4)
wherein D iseffFor an effective duty cycle, D is a first switching tube S1Duty cycle of the drive signal of (1), TdIs a first switch tube S1And a second switch tube S2The dead time of the drive signal, TsIs a first switch tube S1And a second switch tube S2The period of the drive signal.
Further, from fig. 4(c), it can be obtained:
from equations (3) - (5), the voltage gain of the high gain converter for photovoltaic dc modules presented herein can be derived when it contains n boost units:
disregarding losses, there are:
UinIin=UoIo (7)
in the formula of UinFor photovoltaic cell panel voltage, UoIs the average value of the output voltage, IinAnd IoThe average values of the input current and the output current are respectively, and n is the number of the boosting units.
From formulae (6) and (7), it is possible:
as can be seen from the modal analysis, the first switch tube S of the high-gain converter for the photovoltaic DC module provided by the invention1A second switch tube S2Ith boost diode DaiAnd an output diode DoThe voltage stress of (a) is:
in the above formula, US1Is a first switch tube S1Withstand voltage stress, US2Is a second switch tube S2Withstand voltage stress, UDaiFor the ith boost diode DaiWithstand voltage stress, UDoTo output a diode DoThe applied voltage stress, i ═ 1,2, … …, n.
A first capacitor C1A second capacitor C2A second module capacitor CbiFirst module capacitor CaiAn output filter capacitor CoThe voltage stress of (a) is:
UCo=Uo (14)
in the formula of UCoFor outputting filter capacitors CoThe terminal voltage of (c).
It can be seen that the first switch tube S of the high-gain converter for the photovoltaic dc module according to the present invention1A second switch tube S2And an output diode DoAnd ith boost diode DaiHas the same voltage stress and is far smaller than the output voltage. In addition, the voltage stress is continuously reduced along with the increase of the expansion number of the boosting unitsIs small. Therefore, a low voltage rated MOS transistor with a lower on-resistance can be selected.
After entering a steady state, the first capacitor C1A second capacitor C2The ith auxiliary capacitor CbiIth filter capacitor CaiOutput filter capacitor CoIs zero, thereby obtaining an average current equivalent circuit for a high gain converter of a photovoltaic dc module, as can be taken from fig. 6, the input inductance LinA rear stage inductor LmAnd the ith boost inductor LaiThe average current of (d) is:
ith boost diode DaiAnd an output diode DoThe average current of (d) is:
IDai=IDo=Io (16)
it can be seen that: rear stage inductance LmIth boost inductor LaiIth boost diode DaiAnd an output diode DoAre all equal to the average value I of the output currentoRegardless of the number of booster cells, i ═ 1,2, … …, n.
Furthermore, the input inductance LinA rear stage inductor LmAnd the ith boost inductor LaiThe effective values of the currents are respectively:
wherein, ILin,rms、ILm,rmsAre respectively an input inductance LinA rear stage inductor LmThe current effective value of (a); i isLin、ILmAre respectively an input inductance LinA rear stage inductor LmAverage value of current of (a); delta ILin、ΔILmAre respectively an input inductance LinA rear stage inductor LmCurrent peak to peak value.
First switch tube S1And a second switching tube S2The effective values of the currents are respectively:
in the formula (I), the compound is shown in the specification,
IS1,rms、IS2,rmsare respectively a first switch tube S1A second switch tube S2Effective value of current of, Δ ILmIs a post-stage inductor LmCurrent peak-to-peak value of,. DELTA.ILaiBoost the inductance L for the ithaiCurrent peak-to-peak value of (I)LFor synthesizing a current iLMean value,. DELTA.ILFor synthesizing a current iLPeak to peak value of (a).
The ZVS turn-on conditions of the present invention are discussed below.
From the modal analysis, it can be known that: a second switch tube S2ZVS switching-on can be naturally realized, and the first switching tube S is required to be realized1ZVS on, then requires the inductor L of the later stage in the mode 4mAnd the ith boost inductor LaiAll the currents flow out of the node m and satisfy the following conditions:
due to dead time TdVery short, so it can be approximated as the input inductance L in mode 4inA rear stage inductor LmAnd the ith boost inductor LaiAll the currents of (a) remain unchanged, i.e.:
in the formula iLin,valFor input of an inductor LinCurrent valley of (i)Lm,peakIs a post-stage inductor LmPeak of current ofValue iLai,peakBoost the inductance L for the ithaiWherein i is 1,2, … …, n.
From formulas (20) and (21), it is possible to obtain:
in the formula iL,peakFor synthesizing a current iLThe peak value of (c).
Namely:
from the formulas (10) to (13), the latter-stage inductance L can be obtainedmAnd the ith boost inductor LaiSustained forward voltage:
further, a post-stage inductance L can be obtainedmAnd the ith boost inductor LaiCurrent peak-to-peak value of (c):
if the input inductance L is requiredinCurrent pulsation amount Δ I ofLinNot exceeding its maximum average current ILin,maxδ% of (d) then:
if the latter stage inductance LmAnd the ith boost inductor LaiWith the same inductance, the peak-to-peak current values are also equal, and thus the value can be obtained from equation (23):
thus, the ZVS turn-on conditions of the present invention are:
wherein i is 1,2, … …, n.
The converter of the present invention is designed with the following parameters.
Under the condition of different numbers of boosting units, the working principle of the converter provided by the invention for realizing ZVS (zero voltage switching) opening and high gain is similar. Therefore, the present invention takes the case of containing 1 boosting unit (as shown in fig. 7) as an example to design an experimental prototype, and the design indexes are as follows: photovoltaic cell panel voltage U in40V, output voltage U o400V, switching frequency fs110kHz, maximum output power Po,max250W, dead time Td=400ns。
From the above index, the duty ratio at this time can be obtained from equation (8):
if the input inductance L is requiredinCurrent pulsation amount Δ I ofLinNot exceeding its maximum average current ILin,max30% of (I), i.e.. DELTA.ILin≤0.3ILin,maxThen, there are:
input inductor Lin=0.2mH。
Thus, from equation (28):
get the 1 st boost inductance La125 muH, post-stage inductance Lm=25μH。
Based on the modal analysis, the working condition analysis and the parameter design of the converter, an experiment prototype is manufactured to carry out an open loop experiment to verify the boosting capacity of the converter. The specific technical indexes and circuit parameters are as follows: photovoltaic cell panel voltage U in40V, output voltage U o400V, switching frequency fs110kHz, maximum output power Po,max250W, dead time T d400 ns; input inductance Lin0.2mH, 1 st boost inductor La125 muH, post-stage inductance Lm25 muh; input filter capacitor Cin47 muF, first capacitance C110 muF, second capacitance C210 muF, 1 st filter capacitance Ca110 muF, 1 st auxiliary capacitance Cb110 muF, output filter capacitance Co10 μ F; theoretical voltage gain G-10.
FIG. 8(a) shows a driving signal u of the first switch tubegs1Input inductor current iLinVoltage u of photovoltaic cell panelinAnd an output voltage uoThe experimental waveform of (2); FIG. 8(b) shows the driving signal u of the second switch tubegs21 st boost inductor current-iLa1And the inductor current-i of the later stageLmThe experimental waveform of (2); FIG. 8(C) shows the first capacitor C1A second capacitor C21 st filter capacitor Ca1And 1 st auxiliary capacitor Cb1Experimental waveforms of the voltages at both ends; FIG. 8(d) shows the driving signal u of the first switch tubegs1Voltage u between drain and source of the first switching tubeS1A driving signal u of the second switch tubegs2And the voltage u between the drain and the source of the second switch tubeS2The experimental waveform of (2); FIG. 8(e) shows the terminal voltage u of the 1 st boost diode at full load (output power 250W)Da11 st boost diode current iDa1And the terminal voltage u of the output diodeDoCurrent i of the output diodeDoThe experimental waveform of (2); FIG. 8(f) shows the terminal voltage u of the 1 st boost diode at light load (output power 50W)Da11 st boost diode current iDa1And the terminal voltage u of the output diodeDoCurrent i of the output diodeDoExperimental waveforms of (4).
As can be seen from fig. 8(a) and 8 (b): input inductance LinAnd a post-stage inductor Lm1 st boost inductor La1All work in a current continuous mode; input of inductor current iLmAnd 1 st boost inductor current iLa1Are equal to, and-iLm,peak-iLa1,peak>iLin,val(ii) a The actual value of the effective duty ratio is DeffAbout 0.76, and the theoretical value Deff0.75 is very close. As can be seen from fig. 8 (c): each capacitor having a first capacitor C1A second capacitor C21 st filter capacitor Ca1And 1 st auxiliary capacitor Cb1Respectively of voltage stress of UC1=160V、UC2=120V、UCa1=280V、U Cb1240V, all of which are substantially in agreement with the theoretical values. As can be seen from fig. 8 (d): first switch tube S1A first switch tube S2Performing complementary work; first switch tube S1A first switch tube S2Has a voltage stress of US1=U S2160V, which is basically consistent with a theoretical value; drive signal ugs1、ugs2Before the positive pressure comes, the first switch tube S1、S2Terminal voltage u ofS1、uS2Both have decreased to zero, indicating that both achieve ZVS switching on. As can be seen from fig. 8(e) and 8 (f): under full load condition, D1、D2Is small (1A), approximately a natural turn-off (ZCS); under the condition of light load, the two are completely naturally turned off; low voltage stress of UD1=U Do160V, which basically coincides with the theoretical value.
And then carrying out closed-loop simulation on the voltage of the photovoltaic cell panel to verify the feasibility of the control scheme provided by the invention, wherein the specific technical indexes and circuit parameters are as follows: photovoltaic cell plate voltage reference value u in,ref40V, output voltage U o400V, switching frequency fs110kHz, dead time T d400 ns; input inductance Lin0.2mH, 1 st boost inductor La125 muH, post-stage inductance Lm25 muh; input filter capacitorCin47 muF, first capacitance C110 muF, second capacitance C210 muF, 1 st filter capacitance Ca110 muF, 1 st auxiliary capacitance Cb110 muF, output filter capacitance Co10 μ F; theoretical voltage gain G ═ 10; the output end of the photovoltaic cell panel is connected with a storage battery in parallel to simulate a direct current bus and clamp the output voltage at 400V, and the photovoltaic cell panel is simulated by connecting a 47.5V constant-voltage direct current power supply and a variable resistor in series. When the simulation proceeded to 50ms, the variable resistance was momentarily switched from 1 Ω to 1.5 Ω.
FIG. 9 shows the converter of FIG. 3 with input power PinSwitching to input power P of 300WinAs for the dynamic adjustment process at 200W, it can be seen that at the time of 50ms, the current of the photovoltaic panel changes from 7.5A to 5A, the output power of the converter changes, and the input power changes from 300W to 200W; before and after the input power changes, the voltage of the converter photovoltaic cell panel is stabilized at 40V, and the output voltage U iso400V, consistent with theory.
The high-gain converter for the photovoltaic direct-current module has the following advantages: (1) voltage gain of [1+ (1+ n) Deff]/(1-Deff). By adjusting the number of the boosting units, the voltage gain can be flexibly adjusted to enable the boosting units to work under a proper duty ratio D so as to meet the boosting requirements on different occasions; (2) has 2 switching tubes and (n +1) diodes, and the first switching tube S1A second switch tube S2Ith boost diode DaiAnd an output diode DoAll bear the same voltage stress and are [ (n +1) Uin+Uo](n +2), much smaller than the output voltage; (3) first switch tube S1And a second switching tube S2ZVS opening can be realized in the whole load range; ith boost diode DaiAnd an output diode DoThe approximate natural shutoff can be realized under the heavy load condition, and the complete natural shutoff can be realized under the light load condition; wherein i is 1,2, … …, n.
It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
The above description of the embodiments is only intended to facilitate the understanding of the method of the invention and its core idea, and not to limit it. It should be noted that, for those skilled in the art, without departing from the principle of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall into the protection scope of the present invention.
Claims (4)
1. A high-gain converter for a photovoltaic direct current module is characterized by comprising a boosting module and a basic module;
the boost module includes n boost units, and each boost unit includes: boost diode DaFilter capacitor CaAnd an auxiliary capacitor CbBoost inductor La;
The internal connection mode of the boosting unit is as follows: the boost diode DaAnd the boost inductor LaFirst terminal of, said filter capacitor CaThe positive electrodes of the two electrodes are connected; the boost inductor LaAnd the second terminal of the auxiliary capacitor CbThe positive electrodes of the two electrodes are connected;
the connection mode between the boosting units is as follows: boost diode D in the latter boost unitaAnode and auxiliary capacitor C in the previous booster unitbPositive pole of (1), boost inductor L in the previous boost unitaIs connected with the second end of the first end; n auxiliary capacitors C of the boosting unitsbAll of which are negative electrodesIntersecting with point b; n filter capacitors C of the boosting unitsaThe negative electrode of (a) is crossed with the point a;
the basic module comprises a photovoltaic cell panel UinAn input filter capacitor CinAn input inductor LinA rear stage inductor LmA first switch tube S1A second switch tube S2A first capacitor C1A second capacitor C2And an output diode DoAn output filter capacitor CoAnd a load R;
the connection mode of the basic module and the boosting module is as follows: the photovoltaic cell panel UinAnd the input inductance LinFirst terminal of, said input filter capacitance CinThe positive electrodes of the two electrodes are connected; the input inductance LinAnd the second end of the first switch tube S1Drain electrode of (1), the second switching tube S2Source electrode of, the second capacitor C2The negative pole of the voltage boosting module is connected with the point b of the voltage boosting module; the second switch tube S2And the post-stage inductor LmFirst terminal of, said first capacitor C1The positive electrodes of the two electrodes are connected; the back stage inductor LmAnd the second terminal of the second capacitor C2Positive pole of (2), boost diode D of the first boost unit in the boost moduleaThe anodes of the anode groups are connected; the output diode DoAnd the boost inductance L of the last boost unit in the boost moduleaSecond terminal and auxiliary capacitance CbThe positive electrodes of the two electrodes are connected; the output diode DoAnd the output filter capacitor CoThe positive electrode of (a) is connected with the first end of the load R; a second terminal of the load R and the output filter capacitor CoThe negative pole of (1), the point a of the boosting module, the first switch tube S1Source electrode of, the input filter capacitor CinNegative pole of (1), the first capacitor C1And the photovoltaic cell panel UinThe negative electrodes are connected;
the input inductance LinThe inductance value of (a) satisfies:
in the above formula, Deff=D+Td/Ts,DeffFor an effective duty cycle, D is a first switching tube S1Duty cycle of the drive signal of (1), TdIs a first switch tube S1And a second switch tube S2The dead time of the drive signal, TsIs a first switch tube S1And a second switch tube S2Period of the drive signal of (1), LinFor input of an inductor LinPeak to peak value of,. DELTA.ILinIs an input inductance LinCurrent pulsation amount of UinFor the photovoltaic cell panel voltage, fsIs the switching frequency, delta% is the input inductance LinMaximum permissible current ripple and input inductance LinPercentage of maximum average current; po,maxIs the maximum output power;
the back stage inductor LmAnd a boost inductor L in the boost unitaThe inductance value of (a) satisfies:
in the above formula, LmIs a post-stage inductor LmInductance value of, LaFor the step-up inductor LaInductance value of, UoIs the output voltage; n is the number of booster cells.
2. A method of controlling a high gain converter according to claim 1, comprising the steps of:
to photovoltaic cell panel UinIs sampled to obtain a voltage sampling value uin,fFor the photovoltaic cell panel UinIs sampled to obtain a current sampling value iin,fSampling the voltage value uin,fCurrent sample value iin,fSending the voltage into MPPT, and calculating to generate a voltage reference value u of the photovoltaic cell panel through the MPPTin,refSampling the voltage of the photovoltaic cell panel uin,fWith the voltage reference value u of the photovoltaic cell panelin,refComparing to obtain an error signal uin,f-uin,ref;
The error signal uin,f-uin,refSending to a voltage controller to obtain a regulation signal ur;
The regulating signal urWith a unipolar triangular carrier ucCrossing to generate a first switch tube S1PWM drive signal ugs1;
The first switch tube S1The PWM driving signal is inverted to obtain a second switching tube S2PWM drive signal ugs2。
3. The control method of claim 2, wherein the ideal voltage gain of the high-gain converter is [1+ (1+ n) Deff]/(1-Deff)。
4. Control method according to claim 2, characterized in that the first switching tube S1A second switch tube S2And an output diode DoAnd a boost diode DaAll bear the same voltage stress and are [ (n +1) Uin+Uo]/(n+2)。
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202210237775.5A CN114583951A (en) | 2022-03-11 | 2022-03-11 | High-gain converter for photovoltaic direct current module and control method thereof |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202210237775.5A CN114583951A (en) | 2022-03-11 | 2022-03-11 | High-gain converter for photovoltaic direct current module and control method thereof |
Publications (1)
Publication Number | Publication Date |
---|---|
CN114583951A true CN114583951A (en) | 2022-06-03 |
Family
ID=81775011
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN202210237775.5A Withdrawn CN114583951A (en) | 2022-03-11 | 2022-03-11 | High-gain converter for photovoltaic direct current module and control method thereof |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN114583951A (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN115347785A (en) * | 2022-08-24 | 2022-11-15 | 南通大学 | High-efficiency photovoltaic converter without input filter |
CN115347796A (en) * | 2022-08-24 | 2022-11-15 | 南通大学 | High-power-density ZVS high-gain converter based on common-mode inductor |
CN115987103A (en) * | 2023-02-06 | 2023-04-18 | 广东工业大学 | Multi-mode booster circuit, device, control method and medium for miniature photovoltaic system |
CN116388560A (en) * | 2023-06-01 | 2023-07-04 | 深圳市恒运昌真空技术有限公司 | High-gain bidirectional converter |
CN117239885A (en) * | 2023-11-16 | 2023-12-15 | 中山市宝利金电子有限公司 | Energy storage charging circuit with wide voltage range |
-
2022
- 2022-03-11 CN CN202210237775.5A patent/CN114583951A/en not_active Withdrawn
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN115347785A (en) * | 2022-08-24 | 2022-11-15 | 南通大学 | High-efficiency photovoltaic converter without input filter |
CN115347796A (en) * | 2022-08-24 | 2022-11-15 | 南通大学 | High-power-density ZVS high-gain converter based on common-mode inductor |
CN115347796B (en) * | 2022-08-24 | 2024-06-04 | 南通大学 | High-power density ZVS high-gain converter based on common-mode inductance |
CN115347785B (en) * | 2022-08-24 | 2024-06-04 | 南通大学 | High-efficiency photovoltaic converter without input filter |
CN115987103A (en) * | 2023-02-06 | 2023-04-18 | 广东工业大学 | Multi-mode booster circuit, device, control method and medium for miniature photovoltaic system |
CN115987103B (en) * | 2023-02-06 | 2023-07-28 | 广东工业大学 | Multimode booster circuit, device, control method and medium for micro photovoltaic system |
CN116388560A (en) * | 2023-06-01 | 2023-07-04 | 深圳市恒运昌真空技术有限公司 | High-gain bidirectional converter |
CN116388560B (en) * | 2023-06-01 | 2023-08-11 | 深圳市恒运昌真空技术有限公司 | High-gain bidirectional converter |
CN117239885A (en) * | 2023-11-16 | 2023-12-15 | 中山市宝利金电子有限公司 | Energy storage charging circuit with wide voltage range |
CN117239885B (en) * | 2023-11-16 | 2024-03-15 | 中山市宝利金电子有限公司 | Energy storage charging circuit with wide voltage range |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN114583951A (en) | High-gain converter for photovoltaic direct current module and control method thereof | |
de Melo et al. | A modified SEPIC converter for high-power-factor rectifier and universal input voltage applications | |
CN112583252B (en) | High-power-density high-gain converter and control method thereof | |
CN111541369B (en) | Staggered parallel DC/DC boost converter based on switch inductor/switch capacitor unit | |
CN107834886B (en) | A kind of single-stage boost inverter and its control method | |
CN111010043A (en) | Full-bridge LLC resonant converter fixed-frequency control method | |
CN110829837B (en) | Low-voltage stress ZVS high-gain Boost converter | |
CN116191858A (en) | Cuk type power factor correction circuit based on switching inductance | |
CN114583953A (en) | Zero-ripple energy storage bidirectional converter and control method thereof | |
CN114583952A (en) | Bidirectional direct current converter for energy storage system and control method thereof | |
CN110611425B (en) | Current sharing method based on series-parallel Boost converter | |
CN113630009B (en) | High-performance non-isolated bidirectional direct current converter and control method thereof | |
CN112886817B (en) | High-efficiency high-gain converter and control method thereof | |
CN113364294B (en) | Low-voltage stress and low-input current ripple high-gain converter and control method | |
CN114710036A (en) | High-efficiency boost converter for small UPS and control method thereof | |
CN114759781A (en) | Input interleaved parallel soft-switching high-voltage gain DC-DC converter based on switched capacitor | |
CN114583954A (en) | High-gain converter for photovoltaic direct current module and control method thereof | |
Broday et al. | A minimum power loss approach for selecting the turns ratio of a tapped inductor and mode of operation of a 5-switch bidirectional DC-DC Converter | |
Jagtap et al. | A High Gain Modified Voltage Lift Cell Based DC-DC Converter Using Single Switch | |
Mostafapour et al. | A Developed Large Boosting Factor DC‐DC Converter Feasible for Photovoltaic Applications | |
Li et al. | Interleaved high step-up converter with built-in transformer and voltage doubler for PV grid-connected generation systems | |
CN113346744B (en) | Three-inductor high-gain Boost converter | |
CN113595392B (en) | Three-port converter with high boosting capacity and control method thereof | |
Jiang et al. | A Novel DC-DC Boost Converter with High Voltage Conversion Ratio and Zero Current Ripple for Fuel Cell Application | |
CN113572360B (en) | Three-port converter with soft switching capability and control method thereof |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
WW01 | Invention patent application withdrawn after publication |
Application publication date: 20220603 |
|
WW01 | Invention patent application withdrawn after publication |