CN109818495B - String inverter and boost chopper circuit control method thereof - Google Patents
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Abstract
The invention provides a string inverter and a boost chopper circuit control method thereof.A first PV voltage interval corresponding to a current ripple larger than a threshold is determined according to a preset ripple current condition; then, within the first PV voltage interval, PWM control is carried out on the boost chopper circuit at a first switching frequency; and PWM-controlling the boost chopper circuit at a frequency lower than the first switching frequency in a voltage interval other than the first PV voltage interval. That is, when the boost chopper circuit is subjected to PWM control, the invention adopts higher switching frequency to control in a PV voltage interval with larger current ripple so as to reduce the current ripple; the PV voltage interval with smaller current ripple is controlled by adopting lower switching frequency so as to reduce the switching loss; and furthermore, the two constraints of current ripple and switching loss can be compatible.
Description
Technical Field
The invention relates to the technical field of power electronics, in particular to a string inverter and a boost chopper circuit control method thereof.
Background
Due to the nature of the photovoltaic cell itself, its maximum power point is between open and short circuit; and the maximum power point of the LED lamp can change continuously along with the change of environments such as illumination and the like; maximum power point tracking is usually required by regulating inverter control to operate at the maximum power point.
In practical application, however, because the characteristic of the inverter circuit determines that the bus voltage must be greater than the minimum grid-connected voltage, the bus voltage cannot be reduced without limit, and therefore, a first-stage boost chopper circuit is added in the front stage of the inverter circuit in many inverters; as shown in fig. 1, the input end of each Boost circuit in the string inverter is connected with a corresponding PV module, and the output end of each Boost circuit is connected with a bus capacitor, so that the PV module can be controlled to work at a position lower than the minimum grid-connected voltage under the condition of ensuring that the bus voltage is not changed, and the maximum power point tracking in a wider range can be realized.
In the prior art, a PWM (Pulse Width Modulation) mode is usually adopted to control a Boost circuit, and a suitable switching frequency is selected according to various conditions such as cost, devices, control bandwidth and the like in the design process, so as to meet the requirements of stress, temperature and the like under all allowable working conditions. However, under the condition that the input and output voltages of the Boost circuit are not changed, in order to reduce the current ripple of the reactance of the Boost circuit, the switching frequency needs to be increased; however, the higher the switching frequency is, the more the switching times in unit time are, the larger the corresponding switching loss is, the higher the wafer temperature is, and the lower the efficiency is; therefore, the prior art cannot be compatible with the two constraints of current ripple and switching loss.
Disclosure of Invention
The invention provides a string inverter and a boost chopper circuit control method thereof, and provides a boost chopper circuit control scheme which can be compatible with two restriction conditions of current ripple and switching loss.
In order to achieve the purpose, the technical scheme provided by the application is as follows:
the invention provides a boost chopper circuit control method of a string inverter, which comprises the following steps:
determining a first PV voltage interval corresponding to the current ripple larger than a threshold value according to a preset ripple current condition;
within the first PV voltage interval, performing Pulse Width Modulation (PWM) control on a boost chopper circuit at a first switching frequency; and PWM control is carried out on the boost chopper circuit in other voltage intervals except the first PV voltage interval at a frequency lower than the first switching frequency.
Preferably, the first switching frequency is a switching frequency at which the boost chopper circuit operates normally.
Preferably, the frequency lower than the first switching frequency is: a preset fixed frequency, or a frequency that varies with the duty cycle of the boost chopper circuit.
Preferably, the boost chopper circuit duty cycle corresponding to the first PV voltage interval includes 0.5.
Preferably, the first PV voltage interval is (Va, Vb);
the other voltage intervals than the first PV voltage interval include: a second PV voltage interval [0, Va ] and a third PV voltage interval [ Vb, Vstart ];
va is a lower limit value of the first PV voltage interval, Vb is an upper limit value of the first PV voltage interval, and Vstart is a bus voltage of the string inverter in a stable state.
Preferably, in the first PV voltage interval, the boost chopper circuit is subjected to pulse width modulation PWM control at a first switching frequency; and PWM-controlling the boost chopper circuit at a frequency lower than the first switching frequency in a voltage interval other than the first PV voltage interval, including:
within a third PV voltage interval [ Vb, Vstart ], carrying out PWM control on the boost chopper circuit at the third switching frequency; within a first PV voltage interval (Va, Vb), PWM controlling a boost chopper circuit at the first switching frequency; in a second PV voltage interval [0, Va ], performing PWM control on the boost chopper circuit at a second switching frequency;
wherein the second switching frequency is lower than the first switching frequency, and the third switching frequency is lower than or equal to the first switching frequency.
Preferably, in a third PV voltage interval [ Vb, Vstart ], the boost chopper circuit is PWM-controlled at the third switching frequency; within a first PV voltage interval (Va, Vb), PWM controlling a boost chopper circuit at the first switching frequency; in a second PV voltage interval [0, Va ], PWM control is carried out on the boost chopper circuit at a second switching frequency, and the PWM control method comprises the following steps:
firstly, controlling the input voltage of the boost chopper circuit to gradually change from Vstart to Vb through PWM control under the third switching frequency;
controlling the input voltage of the boost chopper circuit to gradually change from Vb to Va by PWM control under the first switching frequency;
and finally, controlling the input voltage of the boost chopper circuit to gradually change from Va to 0 by PWM control under the second switching frequency.
In another aspect, the present invention further provides a string inverter, including: the device comprises a controller, a bus capacitor branch circuit, an inverter circuit, a filter circuit and at least one boost chopper circuit; wherein:
the input end of the boost chopper circuit is connected with the corresponding PV group string;
the output end of the boost chopper circuit is connected with the two ends of the bus capacitor branch circuit and the direct current side of the inverter circuit;
the middle point of the bus capacitor branch is connected with the middle point of the inverter circuit;
the alternating current side of the inverter circuit is connected with a power grid through the filter circuit;
the controller is used for executing the boost chopper circuit control method of the string inverter.
The invention provides a boost chopper circuit control method of a string inverter, which comprises the steps of firstly, determining a first PV voltage interval corresponding to a current ripple larger than a threshold value according to a preset ripple current condition; then, within the first PV voltage interval, PWM control is carried out on the boost chopper circuit at a first switching frequency; and PWM-controlling the boost chopper circuit at a frequency lower than the first switching frequency in a voltage interval other than the first PV voltage interval. That is, when the boost chopper circuit is subjected to PWM control, the invention adopts higher switching frequency to control in a PV voltage interval with larger current ripple so as to reduce the current ripple; the PV voltage interval with smaller current ripple is controlled by adopting lower switching frequency so as to reduce the switching loss; and furthermore, the two constraints of current ripple and switching loss can be compatible.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
Fig. 1 is a schematic diagram of a string inverter provided in the prior art;
fig. 2 is a flowchart of a boost chopper circuit control method of a string inverter according to an embodiment of the present application;
fig. 3 is a specific flowchart of a boost chopper circuit control method for a string inverter according to another embodiment of the present application.
Detailed Description
The technical solutions in the embodiments of the present application will be clearly and completely described below 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 application.
The invention provides a boost chopper circuit control method of a string inverter, and provides a boost chopper circuit control scheme which can be compatible with two restriction conditions of current ripple and switching loss.
The structure of the string inverter is shown in fig. 1, and includes: a controller (not shown in the figure), bus capacitor branches (C1 and C2), an inverter circuit, a filter circuit, and at least one Boost chopper circuit (i.e., a Boost circuit, in fig. 1, three Boost chopper circuits, Boost1, Boost2, and Boost3, are shown as an example); the input end of the boost chopper circuit is connected with the corresponding PV set string (or PV assembly); the output end of the boost chopper circuit is connected with the two ends of the bus capacitor branch circuit and the direct current side of the inverter circuit; the middle point (the connection point of C1 and C2) of the bus capacitor branch is connected with the middle point of the inverter circuit; the alternating current side of the inverter circuit is connected with a power grid through a filter circuit. In practical application, a switch module can be further arranged for realizing controlled connection between each boost chopper circuit and the corresponding PV group string.
In the prior art, when the hardware parameters and the switching frequency of the boost chopper circuit are designed, the boost chopper circuit is usually designed according to the worst allowable working condition, but in the actual situation, the boost chopper circuit does not always work under the worst working condition, so the design of the switching frequency is not very suitable.
Therefore, in the present embodiment, on the basis of maintaining the original detection function and inversion control function, the controller of the string inverter mainly performs the boost chopper circuit control method of the string inverter as shown in fig. 2 when controlling the boost chopper circuit; specifically, the boost chopper circuit control method for the group of string inverters comprises the following steps:
s101, determining a first PV voltage interval corresponding to a current ripple larger than a threshold value according to a preset ripple current condition;
generally, after the boost chopper circuit is operated, the inverter circuit controls the bus voltage to be a fixed value, namely Vbus, and the boost chopper circuit can control the PV string voltage to be operated in a (0, Vbus) range. If the current is continuous, the switching frequency of the PWM signal of the boost chopper circuit is fs, the switching period is Ts, and the duty ratio is D, the ripple current calculation formula of the boost chopper circuit is as follows:
when Δ I is differentiated from D, it is found that the current ripple is largest when D is 0.5, that is, when D is 0.5.
In practical application, a current ripple threshold Δ I 'may be set, and when the current ripple exceeds the threshold Δ I', it is determined that the PWM control under the corresponding switching frequency does not satisfy the preset ripple current condition; the duty ratio is D epsilon (D1, D2) at the moment; d1 is the duty ratio corresponding to the current ripple gradually increasing to exceed the threshold Δ I' with the increase of the duty ratio D; d2 is the duty ratio corresponding to the current ripple reaching the pole and gradually decreasing to be lower than the threshold Δ I' as the duty ratio D increases; and, if the correspondence between the duty ratio and the current ripple is symmetrical about the pole, 0.5-d1 is d 2-0.5. When the current ripple is lower than the threshold value, the PWM control under the corresponding switching frequency is judged to meet the preset ripple current condition; the duty ratio at this time belongs to the interval other than (d1, d 2).
In the working process of the boost chopper circuit, the inverter circuit stabilizes the bus voltage of the boost chopper circuit, and if the boost chopper circuit realizes on-off control of a switching tube of the boost chopper circuit through PWM control with fixed switching frequency, the voltage of the PV string can be gradually reduced along with the increase of the duty ratio. That is, under the same switching frequency, there is a certain corresponding relationship between the duty ratio of the boost chopper circuit PWM signal and the voltage of the PV string.
Therefore, according to the preset ripple current condition, it can be determined that the duty ratio D when the current ripple exceeds the threshold Δ I 'belongs to the interval (D1, D2), and then according to the corresponding relationship between the duty ratio and the voltage of the PV group string, it can be determined that the voltage of the PV group string belongs to the first PV voltage interval corresponding to the interval (D1, D2) when the current ripple exceeds the threshold Δ I'. That is, the duty cycle of the boost chopper circuit corresponding to the first PV voltage interval includes 0.5; if the correspondence between the duty cycle and the current ripple, and the correspondence between the duty cycle and the voltage of the PV string are symmetric about the pole, the duty cycle corresponding to the middle value of the first PV voltage interval is 0.5.
S102, in a first PV voltage interval, performing Pulse Width Modulation (PWM) control on a boost chopper circuit at a first switching frequency; and PWM-controlling the boost chopper circuit at a frequency lower than the first switching frequency in a voltage interval other than the first PV voltage interval.
When the duty ratio is about 0.5, the current ripple is large, and the switching frequency needs to be increased to reduce the reactance ripple current; and in other times, under the condition of meeting the preset ripple current condition, the switching frequency is designed to be smaller, so that the switching loss can be reduced, the efficiency is improved, and the wafer temperature is reduced.
Therefore, the present embodiment implements PWM control for each boost chopper circuit by establishing a functional relationship fs (f) (d) between the switching frequency and the duty ratio; namely: when the duty ratio is about 0.5, such as the interval (d1, d2), and the voltage corresponding to the PV group string belongs to the first PV voltage interval, performing PWM control on the boost chopper circuit at the first switching frequency to reduce the current ripple; in other voltage intervals except the first PV voltage interval, the voltage of the PV group string is subjected to PWM control on the boost chopper circuit at a frequency lower than the first switching frequency so as to reduce the switching loss; and furthermore, the two constraints of current ripple and switching loss can be compatible.
Because the switching frequency of the PWM signal of the boost chopper circuit can meet the worst operating condition requirement when the boost chopper circuit is in normal operation, preferably, the first switching frequency is the switching frequency when the boost chopper circuit is in normal operation.
The frequency lower than the first switching frequency may be a preset fixed frequency, or may also be a frequency that changes with the duty ratio of the boost chopper circuit; it is only necessary to ensure that the frequency is lower than the first switching frequency, depending on the specific application environment, and the protection scope of the present application is ensured.
In another embodiment of the present invention, a specific boost chopper circuit control method for a string inverter is provided, based on the above embodiment, preferably, the first PV voltage interval is (Va, Vb);
the other voltage intervals other than the first PV voltage interval thereof include: a second PV voltage interval [0, Va ] and a third PV voltage interval [ Vb, Vstart ];
va is a lower limit value of the first PV voltage interval, Vb is an upper limit value of the first PV voltage interval, and Vstart is a bus voltage of the string inverter in a stable state.
Correspondingly, step S102 in fig. 2 includes:
within a third PV voltage interval [ Vb, Vstart ], performing PWM control on the boost chopper circuit at a third switching frequency; within a first PV voltage interval (Va, Vb), PWM control is carried out on a boost chopper circuit at a first switching frequency; in a second PV voltage interval [0, Va ], performing PWM control on the boost chopper circuit at a second switching frequency;
the second switching frequency is lower than the first switching frequency, and the third switching frequency is lower than or equal to the first switching frequency.
Preferably, if each specific step in step S102 is executed in a sequential order, as shown in fig. 3, the method includes:
s201, firstly, controlling the input voltage of the boost chopper circuit to gradually change from Vstart to Vb through PWM control under a third switching frequency;
s202, controlling the input voltage of the boost chopper circuit to gradually change from Vb to Va through PWM control under the first switching frequency;
and S203, finally, controlling the input voltage of the boost chopper circuit to gradually change from Va to 0 by PWM control under the second switching frequency.
It is worth noting that the prior art IV curve scan process for PV strings is from open circuit to near short circuit, and the voltage and current are recorded during the process. In the process, as the voltage of the PV set string is reduced, the duty ratio of the PWM signal of the boost chopper circuit is larger and larger. Because the process is generally fast, the current and the conduction time of a switching tube in the boost chopper circuit are changed violently, the temperature of a wafer can be overhigh, and the module is invalid.
In this embodiment, the IV curve scanning process of the boost chopper circuit is divided into three sections: a third PV voltage interval [ Vb, Vstart ], a first PV voltage interval (Va, Vb), and a second PV voltage interval [0, Va ].
The boost chopper circuit operates from the bus voltage Vstart in the steady state of the string inverter. Then, within a third PV voltage interval [ Vb, Vstart ] with smaller current ripple, controlling the input voltage of the boost chopper circuit to gradually change from Vstart to Vb through PWM control under a third switching frequency F3; the duty ratio of the PWM signal in this phase is small, the switching tube generates little heat, so the third switching frequency F3 can be the same frequency as the first switching frequency F1; of course, the third switching frequency F3 may be a frequency lower than the first switching frequency F1; it is not specifically limited herein, and is within the scope of the present application depending on the application environment. Then, in the next stage, that is, in the first PV voltage interval (Va, Vb) where the PWM signal duty ratio is about 0.5 and the current ripple is large, the input voltage of the boost chopper circuit is controlled to gradually change from Vb to Va by PWM control at the first switching frequency F1. Finally, in a second PV voltage interval [0, Va ] with a larger duty ratio and smaller current ripple of the PWM signal, the input voltage of the boost chopper circuit is controlled to gradually change from Va to 0 by PWM control under a second switching frequency F2; since the second switching frequency F2 is lower than the first switching frequency F1, switching loss can be reduced at this stage, efficiency can be improved, and the wafer temperature can be reduced. The relationship between the switching frequency and the three scanning processes is shown in table 1:
TABLE 1 correspondence of switching frequency to IV curve sweep procedure
PV (photovoltaic) group string voltage interval for working of boost chopper circuit | Switching frequency of PWM signal |
[Vb,Vstart] | F3 |
(Va,Vb) | F1 |
[0,Va] | F2 |
In practical applications, it is preferable to set the first switching frequency F1 as the switching frequency of the boost chopper circuit during normal operation; and the frequencies reduced during scanning, namely the third switching frequency F3 and the second switching frequency F2, are set to be a certain proper fixed value; wherein the second switching frequency F2 is a fixed value lower than the first switching frequency F1 and the third switching frequency F3 is a fixed value lower than or equal to the first switching frequency F1; alternatively, the third switching frequency F3 and the second switching frequency F2 may be set to vary with the duty cycle, respectively; it is not specifically limited herein, and is within the scope of the present application depending on the application environment.
The boost chopper circuit control method of the string inverter provided by the embodiment is characterized in that the influence of the switching frequency on the system is different under different working conditions through analysis, through the three-section scanning process, on the premise that the control current ripple does not exceed the threshold value, the switching frequency of a switching tube of the boost chopper circuit is at least reduced at a position with a large duty ratio, the total loss of the boost chopper circuit in the process of scanning a string IV curve can be reduced, the temperature of a wafer is reduced, the service life of the wafer can not be shortened or even the wafer can not be damaged due to overheating, the hardware cost does not need to be increased, and the method is favorable for popularization.
Another embodiment of the present invention further provides a string inverter, as shown in fig. 1, including: a controller (not shown in the figure), bus capacitor branches (C1 and C2), an inverter circuit, a filter circuit, and at least one Boost chopper circuit (i.e., a Boost circuit, in fig. 1, three Boost chopper circuits, Boost1, Boost2, and Boost3, are shown as an example); wherein:
the input end of the boost chopper circuit is connected with the corresponding PV group string; each string of PV groups comprising a plurality of series-connected PV assemblies, or each comprising only one PV assembly;
the output end of the boost chopper circuit is connected with the two ends of the bus capacitor branch circuit and the direct current side of the inverter circuit;
the middle point (the connection point of C1 and C2) of the bus capacitor branch is connected with the middle point of the inverter circuit;
the alternating current side of the inverter circuit is connected with a power grid through a filter circuit;
in practical application, a switch module can be further arranged for realizing controlled connection between each boost chopper circuit and the corresponding PV group string.
The controller is used for executing the boost chopper circuit control method of the string inverter according to any one of the above embodiments.
The process and principle of the boost chopper circuit control method of the string inverter can be referred to the above embodiments, and are not described in detail here.
The embodiments of the invention are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments can be referred to each other. The device disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description.
The foregoing is merely a preferred embodiment of the invention and is not intended to limit the invention in any manner. Although the present invention has been described with reference to the preferred embodiments, it is not intended to be limited thereto. Those skilled in the art can make numerous possible variations and modifications to the present teachings, or modify equivalent embodiments to equivalent variations, without departing from the scope of the present teachings, using the methods and techniques disclosed above. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention are still within the scope of the protection of the technical solution of the present invention, unless the contents of the technical solution of the present invention are departed.
Claims (8)
1. A boost chopper circuit control method for a string inverter, comprising:
determining a first PV voltage interval corresponding to the condition that the current ripple is greater than a threshold value under the same switching frequency according to a preset ripple current condition;
within the first PV voltage interval, PWM control is carried out on the boost chopper circuit at a first switching frequency; and PWM-controlling the boost chopper circuit at a frequency lower than the first switching frequency in at least one voltage interval other than the first PV voltage interval.
2. The boost chopper circuit control method of claim 1, wherein the first switching frequency is a switching frequency at which the boost chopper circuit is normally operated.
3. The boost chopper circuit control method of the string inverter according to claim 1, wherein the frequency lower than the first switching frequency is: a preset fixed frequency, or a frequency that varies with the duty cycle of the boost chopper circuit.
4. The boost chopper circuit control method of claim 1, wherein the boost chopper circuit duty cycle for the first PV voltage interval comprises 0.5.
5. The boost chopper circuit control method of the string inverter according to any one of claims 1 to 4, wherein the first PV voltage interval is (Va, Vb);
at least one voltage interval other than the first PV voltage interval includes: a second PV voltage interval [0, Va ] and a third PV voltage interval [ Vb, Vstart ];
va is a lower limit value of the first PV voltage interval, Vb is an upper limit value of the first PV voltage interval, and Vstart is a bus voltage of the string inverter in a stable state.
6. The boost chopper circuit control method of claim 5, wherein the boost chopper circuit is Pulse Width Modulated (PWM) controlled at a first switching frequency in the first PV voltage interval; and PWM-controlling the boost chopper circuit at a frequency lower than the first switching frequency in at least one voltage section other than the first PV voltage section, including:
within a third PV voltage interval [ Vb, Vstart ], performing PWM control on the boost chopper circuit at a third switching frequency; within a first PV voltage interval (Va, Vb), PWM controlling a boost chopper circuit at the first switching frequency; in a second PV voltage interval [0, Va ], performing PWM control on the boost chopper circuit at a second switching frequency;
wherein the second switching frequency is lower than the first switching frequency, and the third switching frequency is lower than or equal to the first switching frequency.
7. The boost chopper circuit control method of claim 6, wherein the boost chopper circuit is PWM-controlled at the third switching frequency in a third PV voltage interval [ Vb, Vstart ]; within a first PV voltage interval (Va, Vb), PWM controlling a boost chopper circuit at the first switching frequency; in a second PV voltage interval [0, Va ], PWM control is carried out on the boost chopper circuit at a second switching frequency, and the PWM control method comprises the following steps:
firstly, controlling the input voltage of the boost chopper circuit to gradually change from Vstart to Vb through PWM control under the third switching frequency;
controlling the input voltage of the boost chopper circuit to gradually change from Vb to Va by PWM control under the first switching frequency;
and finally, controlling the input voltage of the boost chopper circuit to gradually change from Va to 0 by PWM control under the second switching frequency.
8. A string inverter, comprising: the device comprises a controller, a bus capacitor branch circuit, an inverter circuit, a filter circuit and at least one boost chopper circuit; wherein:
the input end of the boost chopper circuit is connected with the corresponding PV group string;
the output end of the boost chopper circuit is connected with the two ends of the bus capacitor branch circuit and the direct current side of the inverter circuit;
the middle point of the bus capacitor branch is connected with the middle point of the inverter circuit;
the alternating current side of the inverter circuit is connected with a power grid through the filter circuit;
the controller is used for executing the boost chopper circuit control method of the string inverter according to any one of claims 1 to 7.
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Citations (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101534047A (en) * | 2008-03-11 | 2009-09-16 | 通用电气公司 | Boost converter input ripple current reduction circuit |
CN102208868A (en) * | 2011-04-29 | 2011-10-05 | 南京航空航天大学 | Direct-current to direct-current converter with high boost transformation ratio |
CN102223068A (en) * | 2011-06-23 | 2011-10-19 | 安徽工业大学 | Combined type DC-DC (direct current) converter |
CN103475243A (en) * | 2013-09-09 | 2013-12-25 | 泓芯泰业科技(北京)有限公司 | Control system and method for inverter |
CN203491895U (en) * | 2013-09-27 | 2014-03-19 | 王琳 | High voltage step-up ratio double-switch direct current converter |
CN103683313A (en) * | 2012-09-13 | 2014-03-26 | 武汉金天新能源科技有限公司 | Photovoltaic inverter employing hybrid type power device |
CN104104325A (en) * | 2014-08-05 | 2014-10-15 | 阳光电源股份有限公司 | Method and system for controlling series photovoltaic inverter |
CN104820183A (en) * | 2015-05-15 | 2015-08-05 | 阳光电源股份有限公司 | Method and device for detecting on/off of bypass relay in boost chopper circuit |
WO2016035209A1 (en) * | 2014-09-05 | 2016-03-10 | 三菱電機株式会社 | Power conversion device and refrigeration cycle device |
CN207098966U (en) * | 2017-06-01 | 2018-03-13 | 三峡大学 | A kind of PV combining inverters based on charge pump circuit |
CN207150267U (en) * | 2017-08-15 | 2018-03-27 | 国网天津市电力公司 | A kind of single-phase circuit topology suitable for mixed energy storage system |
CN108155780A (en) * | 2018-01-09 | 2018-06-12 | 青岛大学 | Single-stage and-phase voltage source converter with cascade magnetic integrated switch L.C. network |
CN108336920A (en) * | 2018-03-29 | 2018-07-27 | 阳光电源股份有限公司 | A kind of topological circuit of inverter, regulation and control method and photovoltaic generating system |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8080973B2 (en) * | 2008-10-22 | 2011-12-20 | General Electric Company | Apparatus for energy transfer using converter and method of manufacturing same |
US10186970B2 (en) * | 2017-03-03 | 2019-01-22 | Panasonic Automotive Systems Company Of America, Division Of Panasonic Corporation Of North America | Switching audio amplifier |
-
2019
- 2019-03-14 CN CN201910193532.4A patent/CN109818495B/en active Active
Patent Citations (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101534047A (en) * | 2008-03-11 | 2009-09-16 | 通用电气公司 | Boost converter input ripple current reduction circuit |
CN102208868A (en) * | 2011-04-29 | 2011-10-05 | 南京航空航天大学 | Direct-current to direct-current converter with high boost transformation ratio |
CN102223068A (en) * | 2011-06-23 | 2011-10-19 | 安徽工业大学 | Combined type DC-DC (direct current) converter |
CN103683313A (en) * | 2012-09-13 | 2014-03-26 | 武汉金天新能源科技有限公司 | Photovoltaic inverter employing hybrid type power device |
CN103475243A (en) * | 2013-09-09 | 2013-12-25 | 泓芯泰业科技(北京)有限公司 | Control system and method for inverter |
CN203491895U (en) * | 2013-09-27 | 2014-03-19 | 王琳 | High voltage step-up ratio double-switch direct current converter |
CN104104325A (en) * | 2014-08-05 | 2014-10-15 | 阳光电源股份有限公司 | Method and system for controlling series photovoltaic inverter |
WO2016035209A1 (en) * | 2014-09-05 | 2016-03-10 | 三菱電機株式会社 | Power conversion device and refrigeration cycle device |
CN104820183A (en) * | 2015-05-15 | 2015-08-05 | 阳光电源股份有限公司 | Method and device for detecting on/off of bypass relay in boost chopper circuit |
CN207098966U (en) * | 2017-06-01 | 2018-03-13 | 三峡大学 | A kind of PV combining inverters based on charge pump circuit |
CN207150267U (en) * | 2017-08-15 | 2018-03-27 | 国网天津市电力公司 | A kind of single-phase circuit topology suitable for mixed energy storage system |
CN108155780A (en) * | 2018-01-09 | 2018-06-12 | 青岛大学 | Single-stage and-phase voltage source converter with cascade magnetic integrated switch L.C. network |
CN108336920A (en) * | 2018-03-29 | 2018-07-27 | 阳光电源股份有限公司 | A kind of topological circuit of inverter, regulation and control method and photovoltaic generating system |
Non-Patent Citations (2)
Title |
---|
Nanjun Lu;Branislav Hredzak.Current Ripple Reduction for Photovoltaic Powered Single-Phase Buck-Boost Differential Inverter under Nonlinear Loads.《2018 7th International Conference on Renewable Energy Research and Applications (ICRERA)》.2018,第1-5页. * |
一种多输入端口的多电平高频逆变器;刘俊峰,等;《电工技术学报》;20161231(第S1期);第111-115页 * |
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