WO2022037522A1 - 一种供电系统及方法 - Google Patents
一种供电系统及方法 Download PDFInfo
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- WO2022037522A1 WO2022037522A1 PCT/CN2021/112746 CN2021112746W WO2022037522A1 WO 2022037522 A1 WO2022037522 A1 WO 2022037522A1 CN 2021112746 W CN2021112746 W CN 2021112746W WO 2022037522 A1 WO2022037522 A1 WO 2022037522A1
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- switch
- voltage compensation
- string
- compensation unit
- unit
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- 238000000034 method Methods 0.000 title claims abstract description 28
- 239000004065 semiconductor Substances 0.000 claims description 137
- 238000010586 diagram Methods 0.000 description 21
- 238000004146 energy storage Methods 0.000 description 15
- 230000003068 static effect Effects 0.000 description 14
- 238000006243 chemical reaction Methods 0.000 description 6
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 description 2
- 230000006978 adaptation Effects 0.000 description 2
- OJIJEKBXJYRIBZ-UHFFFAOYSA-N cadmium nickel Chemical compound [Ni].[Cd] OJIJEKBXJYRIBZ-UHFFFAOYSA-N 0.000 description 2
- 230000005669 field effect Effects 0.000 description 2
- 229910001416 lithium ion Inorganic materials 0.000 description 2
- 230000003071 parasitic effect Effects 0.000 description 2
- 229920000642 polymer Polymers 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 210000004027 cell Anatomy 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052987 metal hydride Inorganic materials 0.000 description 1
- 230000010363 phase shift Effects 0.000 description 1
- 238000010248 power generation Methods 0.000 description 1
- 210000000352 storage cell Anatomy 0.000 description 1
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Classifications
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J1/00—Circuit arrangements for dc mains or dc distribution networks
- H02J1/10—Parallel operation of dc sources
-
- 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
- H02M1/0083—Converters characterised by their input or output configuration
- H02M1/0093—Converters characterised by their input or output configuration wherein the output is created by adding a regulated voltage to or subtracting it from an unregulated input
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
- H02J7/34—Parallel operation in networks using both storage and other dc sources, e.g. providing buffering
- H02J7/35—Parallel operation in networks using both storage and other dc sources, e.g. providing buffering with light sensitive cells
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J1/00—Circuit arrangements for dc mains or dc distribution networks
- H02J1/10—Parallel operation of dc sources
- H02J1/106—Parallel operation of dc sources for load balancing, symmetrisation, or sharing
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/002—Flicker reduction, e.g. compensation of flicker introduced by non-linear load
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
- H02J7/0013—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries acting upon several batteries simultaneously or sequentially
-
- 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
-
- 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
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J1/00—Circuit arrangements for dc mains or dc distribution networks
- H02J1/10—Parallel operation of dc sources
- H02J1/102—Parallel operation of dc sources being switching converters
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2207/00—Indexing scheme relating to details of circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
- H02J2207/20—Charging or discharging characterised by the power electronics converter
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2300/00—Systems for supplying or distributing electric power characterised by decentralized, dispersed, or local generation
- H02J2300/20—The dispersed energy generation being of renewable origin
- H02J2300/22—The renewable source being solar energy
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2300/00—Systems for supplying or distributing electric power characterised by decentralized, dispersed, or local generation
- H02J2300/20—The dispersed energy generation being of renewable origin
- H02J2300/22—The renewable source being solar energy
- H02J2300/24—The renewable source being solar energy of photovoltaic origin
- H02J2300/26—The renewable source being solar energy of photovoltaic origin involving maximum power point tracking control for photovoltaic sources
-
- 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
- H02M1/0067—Converter structures employing plural converter units, other than for parallel operation of the units on a single load
- H02M1/0077—Plural converter units whose outputs are connected in series
Definitions
- the present application relates to the technical field of power supply, in particular to a power supply system and method.
- a string is composed of multiple photovoltaic modules or multiple batteries in series, and a power supply system can be formed by connecting multiple strings in parallel.
- This power supply system can be widely used in scenarios such as solar power generation and uninterruptible power supply.
- each string in the prior art adopts the power supply system as shown in Fig. 1, in which DC is connected to the branch where each string is located.
- -DC converter Direct-Current-Direct-Current converter, a voltage converter that converts the input DC voltage into a set DC voltage and outputs it
- each DC-DC converter is respectively connected to the output voltage of the branch
- each string in the prior art is connected in series with a DC-DC converter, and the output current of the string must flow through the DC-DC converter, which brings about the problem of high system loss.
- the present application provides a power supply system and method, which can reduce system loss and system cost.
- a first aspect of an embodiment of the present application provides a power supply system, including: a first branch where the first group string is located, a second branch where the second group string is located, a switch unit, a first voltage compensation unit, and a controller ;
- the switch unit selects to connect the first voltage compensation unit to the first branch according to the voltage compensation enable signal sent by the controller, so that the first voltage compensation unit compensates the output voltage of the first branch , the voltage compensation enable signal is generated by the controller according to the working state parameters of the first group of strings and the working state parameters of the second group of strings. That is, according to the working state parameters between different strings, only the voltage compensation unit is connected to the branch where the string that needs voltage compensation is located, and the branch where the string that does not need voltage compensation is located is not connected.
- the voltage compensation unit avoids unnecessary system loss caused by the voltage compensation unit in the branches that do not need voltage compensation, thereby reducing the system loss.
- the power supply system further includes a first DC bus and a second DC bus;
- the first voltage compensation unit includes a first output terminal and a second output terminal, and the above-mentioned first voltage compensation unit includes a first output terminal and a second output terminal.
- the first output end of a voltage compensation unit is connected to the first DC bus;
- the switch unit connects the second output end of the first voltage compensation unit to the first group string according to the voltage compensation enable signal one end; the other end of the first set of strings is connected to the second DC bus.
- the first DC bus may be a positive DC bus or a negative DC bus
- the switch unit and the first voltage compensation unit may be arranged on either the positive DC bus side or the negative DC bus side
- the switch unit connects one end of the second group of strings to the first DC bus according to the voltage compensation enable signal ;
- the other end of the second group string is connected to the second DC bus.
- the second group of strings is directly connected to the DC bus without passing through the first voltage compensation unit, so as to avoid unnecessary loss of the voltage compensation unit in the second branch.
- the first voltage compensation unit further includes a first input terminal and a second input end;
- the first input terminal of the first voltage compensation unit is connected to the first DC bus, and the second input terminal of the first voltage compensation unit is connected to the second DC bus.
- the output of the second group of strings is actually used as the power supply of the first voltage compensation unit, avoiding external power supply, and reducing the system power supply. quantity, improving the simplicity of the system.
- the first group string includes at least two sub-group strings.
- at least two sub-groups are connected in series and parallel, and a switch unit and a voltage compensation unit are shared, which can further reduce the system cost.
- the output voltage intervals corresponding to the respective maximum power points of the at least two substrings included in the first group string at least partially overlap.
- the switch unit includes a first voltage compensation unit between the first voltage compensation unit and the first group string.
- a switching sub-switch the first switching sub-switch is a contact switch or a semiconductor switch;
- the switch unit controls the first switch sub-switch to connect the first voltage compensation unit and the first string according to the voltage compensation enable signal.
- the above switch unit further includes a second switch sub-switch
- the switch unit controls the second switch sub-switch to connect the first DC bus in the power supply system with the second group string according to the voltage compensation enable signal.
- the first switching sub-switch includes a first semiconductor switch and a second semiconductor switch, wherein the first semiconductor switch is used to connect the a voltage compensation unit and the first string, the second semiconductor switch is used for disconnecting the first string and the first DC bus in the power supply system;
- the switch unit controls the first semiconductor switch to connect the first voltage compensation unit and the first string according to the voltage compensation enable signal, and controls the second semiconductor switch to disconnect the first string and the first string DC bus.
- the first switching sub-switch includes a third semiconductor switch and a diode, wherein the third semiconductor switch is used to connect the first voltage compensation The unit and the first group of strings, the diode is in a reverse cut-off state when the third semiconductor switch connects the first voltage compensation unit and the first group of strings, so as to disconnect the first group of strings from the first group of strings.
- a first DC bus in the power supply system
- the switch unit controls the third semiconductor switch to connect the first voltage compensation unit and the first string according to the voltage compensation enable signal, and disconnect the first string from the first DC bus.
- the controller is further based on the operating state parameters of the first group string and the operating state of the second group string. parameters, determine the voltage compensation reference value, and send the voltage compensation reference value to the first voltage compensation unit, and the first voltage compensation unit compensates the output voltage of the first branch according to the voltage compensation reference value.
- the first voltage compensation unit includes a non-isolated step-down conversion circuit.
- a small-sized and high-efficiency non-isolated step-down converter circuit is used as the voltage compensation unit, which can reduce the system volume and improve the system efficiency.
- the above-mentioned power supply system includes N branches where N group strings are located and M voltage compensation units , N and M are both positive integers, and M is less than N; the N branches include the first branch and the second branch, the M voltage compensation units include the first voltage compensation unit; the switch unit , which is used to connect some or all of the voltage compensation units to some branches respectively according to the above voltage compensation enable signal.
- the voltage compensation unit by connecting the voltage compensation unit to the branch that needs voltage compensation, and not to the branch that does not need voltage compensation, the voltage compensation unit is not connected, so as to avoid the voltage compensation unit not needing voltage compensation. Unnecessary system losses are caused in the branches, and the number of voltage compensation units is less than the number of strings. Compared with the prior art, the number of voltage compensation units is equal to the number of strings, which can reduce the number of voltage compensation units and system costs.
- each group string includes at least one DC component and a converter corresponding to the DC component.
- the controller is used to adjust the working state of the above-mentioned corresponding DC components.
- the converter converts the input voltage into a constant voltage by buck-boosting, that is, the converter is used to adjust the voltage of the DC components in the string, thereby optimizing the working state of the DC components.
- the first string and the second string are photovoltaic strings.
- the above-mentioned first group of strings and the above-mentioned second group of strings are storage Can battery strings.
- a second aspect of the embodiments of the present application provides a string compensation method, which is applied to a power supply system, where the power supply system includes a first branch where the first string is located, a second branch where the second string is located, and a first voltage Compensation unit and controller, the above method includes:
- Receive a voltage compensation enable signal from the controller connect the first voltage compensation unit to the first branch according to the voltage compensation enable signal, and the voltage compensation enable signal is the operation of the controller according to the first string
- the state parameter and the working state parameter of the second group string are generated; the above-mentioned first voltage compensation unit is used to compensate the output voltage of the above-mentioned first branch. That is, according to the working state parameters between different strings, only the voltage compensation unit is connected to the branch where the string that needs voltage compensation is located, and the branch where the string that does not need voltage compensation is located is not connected.
- the voltage compensation unit avoids unnecessary system loss caused by the voltage compensation unit in the branches that do not need voltage compensation, thereby reducing the system loss.
- the power supply system further includes a first DC bus and a second DC bus;
- the first voltage compensation unit includes a first output terminal and a second output terminal, and the above-mentioned first voltage compensation unit includes a first output terminal and a second output terminal.
- a first output end of a voltage compensation unit is connected to the first DC bus;
- the second output end of the first voltage compensation unit is connected to one end of the first group string; the other end of the first group string is connected to the second DC bus.
- the above method further includes:
- one end of the second group of strings is connected to the first DC bus; the other end of the second group of strings is connected to the second DC bus.
- the switch unit includes a first switch sub-switch between the first voltage compensation unit and the first string, and the switch unit
- the first switch sub-switch is a contact switch or a semiconductor switch
- the first switching sub-switch is controlled to connect the first voltage compensation unit and the first group of strings.
- the switch unit further includes a second switch sub-switch; the method further includes:
- the second switching sub-switch is controlled to connect the first DC bus in the power supply system with the second group string.
- the above-mentioned first switching sub-switch includes a first semiconductor switch and a second semiconductor switch;
- the first semiconductor switch is controlled to connect the first voltage compensation unit and the first string
- the second semiconductor switch is controlled to disconnect the first string and the first DC bus.
- the above-mentioned first switching sub-switch includes a third semiconductor switch and a diode
- the third semiconductor switch is controlled to connect the first voltage compensation unit and the first group of strings, and the diode is in a reverse cut-off state, thereby disconnecting the first group of strings and the first group of strings.
- DC bus According to the voltage compensation enable signal, the third semiconductor switch is controlled to connect the first voltage compensation unit and the first group of strings, and the diode is in a reverse cut-off state, thereby disconnecting the first group of strings and the first group of strings.
- the above-mentioned controller is further configured to perform according to the working state parameters of the above-mentioned first group of strings and the above-mentioned second group of strings the working state parameters, determine the voltage compensation reference value, and send the voltage compensation reference value to the first voltage compensation unit. to compensate.
- the above-mentioned power supply system includes N branches where N group strings are located and M voltage compensation units, N and M are both positive integers, and M is less than N; the N branches include the first branch and the second branch, and the M voltage compensation units include the first voltage compensation unit;
- the above method also includes:
- some or all of the voltage compensation units are respectively connected to some branches.
- each group string includes at least one DC component and a converter corresponding to the DC component
- the above-mentioned controller is also used for controlling the converter to adjust the working state of the above-mentioned corresponding DC components.
- Fig. 1 is a kind of power supply system that the prior art provides
- FIG. 2 is a structural block diagram of a power supply system provided by an embodiment of the present application.
- FIG. 3 is a schematic circuit diagram of a voltage compensation unit provided by an embodiment of the present application.
- FIG. 4 is a schematic diagram of a system architecture of a power supply system provided by an embodiment of the present application.
- 5A-5C are schematic diagrams of a switch provided by an embodiment of the present application, respectively;
- FIG. 6 is a schematic diagram of a system architecture of another power supply system provided by an embodiment of the present application.
- FIG. 7 is a schematic diagram of another switch provided by an embodiment of the present application.
- FIG. 8 is a schematic diagram of a system architecture of another power supply system provided by an embodiment of the present application.
- FIG. 9 is a schematic diagram of another switch provided by an embodiment of the present application.
- FIG. 10 is a schematic diagram of a system architecture of another power supply system provided by an embodiment of the present application.
- FIG. 11 is a schematic diagram of a system architecture of another power supply system provided by an embodiment of the present application.
- FIG. 12 is a voltage-power curve between substrings according to an embodiment of the present application.
- FIG. 13 is a schematic diagram of a system architecture of another power supply system provided by an embodiment of the present application.
- FIG. 14A-FIG. 14B are schematic diagrams of another kind of switch provided by the embodiment of the present application respectively;
- FIG. 15A-FIG. 15D are schematic diagrams of another switch provided by the embodiment of the present application, respectively.
- each string is connected in parallel, no matter what the voltage at both ends of the string is connected in parallel, each string cannot work in its own optimal state. Therefore, as shown in Figure 1, a DC-DC converter is connected to the branch where each string is located, and the output current of each string must pass through the DC-DC converter, which brings about the problem of high system loss. .
- the voltage compensation unit is selected to be connected to the branch where the strings that need voltage compensation are located, and the branch where the strings that do not need voltage compensation are located is not connected.
- the input voltage compensation unit reduces the system loss and reduces the system cost.
- each string included in the power supply system provided by the present application is a photovoltaic string, and each photovoltaic string may include multiple series and/or PV modules connected in parallel.
- the power supply system may further include a photovoltaic inverter control module, and the photovoltaic inverter control module inverts and outputs the output voltage of each photovoltaic string.
- the power supply system can transmit the inverted voltage to the power grid.
- the power supply system can also be applied to the uninterruptible power supply scenario, that is, an energy storage device can be installed between the photovoltaic inverter control module and the power grid. Batteries, such as nickel-cadmium batteries, nickel-hydrogen batteries, lithium-ion batteries, lithium-polymer batteries, etc.
- the controller obtains the working state parameters of each PV string, such as the output voltage, and when the working state parameters of the PV strings are different, generates a voltage compensation enable signal, and sends the voltage compensation enable signal to the switch unit in the power supply system.
- the switch unit Based on the voltage compensation enable signal, the switch unit selects to connect the voltage compensation unit in the power supply system to the branch that needs voltage compensation, and the branch that does not need voltage compensation is not connected to the voltage compensation unit , to avoid unnecessary system losses caused by the voltage compensation unit in the branches that do not need voltage compensation, and the number of voltage compensation units is less than the number of strings, compared with the number of voltage compensation units in the prior art that is equal to the number of strings, you can Reduce the number of voltage compensation units and reduce system cost.
- the controller may be provided in the photovoltaic inverter control module or each string.
- each string included in the power supply system provided by the present application is an energy storage battery string, and each energy storage battery string A string may include multiple energy storage cells connected in series and/or in parallel.
- the input end of the power supply system is connected with the charging equipment, and the output end is connected with the electric equipment.
- the charging device may be, for example, a charging pile or a power grid, and the electrical device may be, for example, an in-vehicle system or the like.
- the power supply system may be connected to the electrical equipment through a DC-DC converter, and the DC-DC converter may convert the output voltage of the power supply system into a preset fixed voltage value for output to the electrical equipment.
- the controller obtains the working state parameters of each energy storage battery string, such as battery voltage, charging current, etc., in the case of the working state parameters of the energy storage battery string, generates a voltage compensation enable signal, and switches to the power supply system.
- the switch unit sends the voltage compensation enable signal, so that the switch unit selects to connect the voltage compensation unit in the power supply system to the branch that needs voltage compensation based on the voltage compensation enable signal, instead of the branch that needs voltage compensation.
- the voltage compensation unit is not connected to the circuit to avoid unnecessary system loss caused by the voltage compensation unit in the branch that does not need voltage compensation, and the number of voltage compensation units is less than the number of strings, compared with the voltage compensation units in the prior art.
- the number is equal to the number of strings, which can reduce the number of voltage compensation units and reduce system costs.
- the controller obtains that the battery voltage of the first energy storage battery string is 6V, and the battery voltage of the second energy storage battery string is 8V, Generate a voltage compensation enable signal, and send the voltage compensation enable signal to the switch unit in the power supply system, so that the switch unit connects the voltage compensation unit to the first energy storage battery string based on the voltage compensation enable signal
- the output voltage of the voltage compensation unit is 2V, so that the first energy storage battery string will not be overcharged or overdischarged, while the second energy storage battery string can be fully charged or fully discharged. That is, it can be understood that the battery voltages between the energy storage battery strings reach an equilibrium state.
- the controller may be provided in a power supply system, a charging device or an electrical device.
- FIG. 2 is a structural block diagram of a power supply system provided by an embodiment of the present application.
- the power supply system may include: a first branch 201 where the first string 2011 is located, a second branch 202 where the second string 2022 is located, a switch unit 203 and a first voltage compensation unit 204 .
- the first branch 201 is connected in parallel with the second branch 202
- the switch unit 203 is connected to the first branch 201 , the second branch 202 and the first voltage compensation unit 204 respectively.
- the switch unit 203 connects the first voltage compensation unit 204 to the first branch 201 according to the voltage compensation enable signal received from the controller 207 .
- the input terminal of the controller 207 is connected to the first group string 2011 and the second group string 2022, and the input terminals connected to the first group string 2011 and the second group string 2022 may be the same port or different ports.
- the output terminal of the controller 207 is connected to the first voltage compensation unit 204 .
- the controller 207 can acquire the working state parameters of the first string 2011 and the second string 2022 in real time, and generate the above-mentioned voltage compensation enable signal according to the working state parameters of the first string 2011 and the working state parameters of the second string 2022 .
- the first voltage compensation unit 204 compensates the output voltage of the first branch 201 .
- the working state parameter of the group string may be the output voltage, and/or the output current, and/or the output power, etc. of the group string, and the present application takes the output voltage as an example for description.
- the controller 207 acquires the operating state parameters of the first string 2011 and the second string 2022 , and generates the voltage compensation enable signal according to the operating state parameters of the first string 2011 and the operating state parameters of the second string 2022 .
- the controller 207 can generate a voltage compensation enable signal, and switch to the The switch unit 203 sends the voltage compensation enable signal, and when the switch unit 203 receives the voltage compensation enable signal, controls the first voltage compensation unit 204 to access the first branch 201 .
- the first voltage compensation unit 204 is only connected to the first branch 201 that needs voltage compensation, and the second branch 202 that does not need voltage compensation is not connected to the first voltage compensation unit 204, so as to avoid the voltage compensation unit in the first Unnecessary system losses are caused in the two branches 202, and at the same time, the number of voltage compensation units in the power supply system can be reduced, and the system cost can be reduced.
- the power supply system further includes a first DC bus 205 and a second DC bus 206
- the first voltage compensation unit 204 includes a first output terminal and a second output terminal, wherein the first output terminal is connected to The first DC bus 205 .
- the switch unit 203 controls the first voltage compensation unit 204 to access the first branch 201, which can be specifically implemented as connecting the second output end of the first voltage compensation unit 204 to the first branch circuit 201.
- One end of the first set of strings 2011. The other end of the first string 2011 is connected to the second DC bus 206 .
- the switch unit 203 connects one end of the second group string 2022 to the first DC bus 205 when receiving the above-mentioned voltage compensation enable signal.
- the other end of the second string 2022 is connected to the second DC bus 206 .
- the first voltage compensation unit 204 is neither connected to the first branch 201 nor the second branch 202 .
- the controller 207 may not generate the above voltage according to the operating state parameters of the first string 2011 and the operating state parameters of the second string 2022
- the compensation enable signal or the voltage compensation default signal is generated.
- the switch unit 203 does not receive the voltage compensation enable signal or receives the voltage compensation default signal, it controls the first voltage compensation unit 204 to neither access the first branch. 201 is also not connected to the second branch 202 .
- the power supply system is applied to photovoltaics
- the first string 2011 and the second string 2022 are photovoltaic strings
- the controller 207 may be provided in a photovoltaic inverter control module in the power supply system.
- the first group string 2011 and the second group string 2022 are respectively provided with processors, and each processor can collect the working state parameters of the corresponding group strings, and summarize the collected working state parameters into any
- the processor that obtains all the working state parameters of the strings is the controller 207 .
- the controller 207 can also determine the voltage compensation reference value according to the working state parameter of the first group string 2011 and the working state parameter of the second group string 2022, and send the voltage compensation reference value to the first voltage compensation unit 204,
- the first voltage compensation unit 204 is made to compensate the output voltage of the first branch 201 according to the voltage compensation reference value, that is, the output voltage of the first voltage compensation unit 204 is equal to the voltage compensation reference value.
- the voltage compensation reference value is 100V, that is, the output voltage of the first voltage compensation unit 204 is 100V.
- the input of the first voltage compensation unit 204 may be from a DC voltage source independent of the power supply system. In another alternative embodiment, the input of the first voltage compensation unit 204 may be the second set of strings 2022 . In a specific implementation, the first voltage compensation unit 204 further includes a first input end and a second input end, the first input end of the first voltage compensation unit 204 is connected to the first DC bus 205 , and the first voltage compensation unit 204 The second input terminal is connected to the second DC bus 206 .
- the first input terminal of the first voltage compensation unit 204 is a negative input terminal; when the first DC bus 205 is a positive DC bus, the first input terminal of the first voltage compensation unit 204 The input terminal is the positive input terminal.
- the first voltage compensation unit 204 may include a non-isolated step-down conversion circuit.
- FIG. 3 is a circuit schematic diagram of a voltage compensation unit provided by an embodiment of the present application.
- the non-isolated step-down conversion circuit ie, the buck circuit
- the non-isolated step-down conversion circuit includes a switch K1, an inductor L1, a diode D5 and a capacitor C1. It can be understood that the non-isolated step-down conversion circuit represents the difference between the input and output of the conversion circuit. It has an electrical connection, which is different from the use of a transformer in an isolated circuit to electrically isolate the input and output of the conversion circuit.
- the switch K1 can be an insulated gate bipolar transistor (Insulated Gate Bipolar Transistor, IGBT) and its anti-parallel diode, or can be a metal-oxide-semiconductor field-effect transistor (Metal-Oxide-Semiconductor Field-Effect Transistor, MOSFET).
- IGBT Insulated Gate Bipolar Transistor
- MOSFET Metal-Oxide-Semiconductor Field-Effect Transistor
- the input and output are isolated, otherwise the converter cannot work normally, but the isolated converter is bulky and low in efficiency.
- the two strings share a voltage compensation unit, and the voltage compensation unit uses the string that does not need voltage compensation as the input power supply, and outputs to the string that needs voltage compensation, so it can be small in size and high in efficiency.
- the non-isolated step-down converter circuit reduces the system volume and improves the system efficiency.
- the first voltage compensation unit 204 may also use an isolated resonant circuit, an isolated phase-shift circuit or a flyback circuit.
- switch unit The specific implementation of the switch unit will be exemplarily described below with reference to FIGS. 4 to 9 .
- FIG. 4 is a schematic diagram of a system architecture of a power supply system provided by an embodiment of the present application.
- the power supply system in this embodiment may include a first branch 401 where a first group string 4011 is located, a second group string The second branch 402 where 4022 is located, the switch unit 403 and the first voltage compensation unit 404.
- the switch unit 403 includes a first switch sub-switch 4031 between the first voltage compensation unit 404 and the first string 4011, and the switch unit 403 compensates according to the voltage received from the controller (not shown in the figure).
- the enable signal controls the first switching sub-switch 4031 to connect the first voltage compensation unit 404 and the first group string 4011 .
- the controller may be located in the photovoltaic inverter control module included in the power supply system of this embodiment.
- the controller generates the above voltage compensation enable signal, which may be sent to the switch unit 403 , or sent to at least one processor, and the processor may forward the signal to the switch unit 403 .
- the first switching sub-switch 4031 may be a contact switch, including a first terminal, a second terminal and a third terminal.
- the first end of the first switching sub-switch 4031 is connected to one end of the first group string 4011; the second end of the first switching sub-switch 4031 is connected to the second output end of the first voltage compensation unit 404; the first switching sub-switch 4031
- the third end of the first string 4011 and the other end of the second string 4022 are respectively connected to the second DC bus 406 .
- the first DC bus 405 may be a positive DC bus or a negative DC bus.
- the switch unit 403 controls the first switch sub-switch 4031 to connect the first voltage compensation unit 404 and the first group string 4011, and specifically controls the first end of the first switch sub-switch 4031 to connect with the second end.
- the first switch sub-switch 4031 may include a single changeover contact switch as shown in FIG. 5A .
- the single change-over contact switch includes two stationary contacts a2 and a3, a moving contact a1 and a coil, wherein a1 is connected to the first end of the first changeover sub-switch 4031, and a2 is connected to the first end of the first changeover sub-switch 4031 The two terminals are connected, and a3 is connected to the third terminal of the first switch sub-switch 4031 .
- the switch unit 403 controls the coil of the single change-over contact switch to flow current, so that a1 and a2 are in contact, that is, the first end of the first switch sub-switch 4031 is connected to the second end, thereby connecting the first voltage compensation unit 404 and the second end.
- a1 and a2 are in contact, that is, the first end of the first switch sub-switch 4031 is connected to the second end, thereby connecting the first voltage compensation unit 404 and the second end.
- a1 and a2 are in contact, that is, the first end of the first switch sub-switch 4031 is connected to the second end, thereby connecting the first voltage compensation unit 404 and the second end.
- String 4011 and first DC bus 405 exemplary, in the default state of the single change-over contact switch, no current flows through the coil, and a1 is in contact with a3, that is, the default state of the first switch sub-switch 4031 is that
- the first switch sub-switch 4031 may include two single normally open contact switches as shown in FIG. 5B .
- Each single normally open contact switch includes a static contact, a moving contact and a coil.
- the single normally open contact switch can be understood as the static contact and the moving contact are disconnected in the default state.
- the moving contacts of the two single normally open contact switches are b1 and b2 respectively, and the static contacts of the two single normally open contact switches are b3 and b4 respectively.
- b1 and b2 are both connected to the first end of the first switch sub-switch 4031
- b3 and b4 may be connected to either the second end or the third end of the first switch sub-switch 4031 .
- b3 is connected to the second end of the first changeover sub-switch 4031, and b4 is connected to the third end of the first changeover sub-switch 4031.
- the changeover switch unit 403 controls the coil of the single normally open contact switch where b3 is located to flow current. , so that b1 and b3 are in contact, that is, the first end of the first switching sub-switch 4031 is connected to the second end, so that the first voltage compensation unit 404 and the first group string 4011 are connected.
- the switch unit 403 controls the coil of the single normally open contact switch where b4 is located to flow current, and b2 is in contact with b4, that is, the first end of the first changeover sub-switch 4031 is connected to the third end, Thus, the first group string 4011 and the first DC bus 405 are connected.
- the first switch sub-switch 4031 may include a single normally open contact switch and a single normally closed contact switch as shown in FIG. 5C , the single normally open contact switch and the single normally closed contact switch Contact switches include a static contact, a moving contact and a coil.
- the difference between the single normally closed contact switch and the single normally open contact switch is that the static contact and the moving contact of the single normally closed contact switch are in contact by default.
- the moving contact of the single normally closed contact switch is c2, and the static contact is c4; the moving contact of the single normally open contact switch is c1, and the static contact is c3.
- both c1 and c2 are connected to the first terminal of the first switch sub-switch 4031
- c3 is connected to the second terminal of the first switch sub-switch 4031
- c4 is connected to the third terminal of the first switch sub-switch 4031 .
- the switch unit 403 controls the coil of the single normally open contact switch where c3 is located to flow current, so that c1 is in contact with c3, that is, the first end of the first switch sub-switch 4031 is connected to the second end, thereby connecting the first voltage compensation unit 404 with the first set of strings 4011.
- the switch unit 403 Since the single normally closed contact switch is in contact with c2 and c4 in the default state, that is, the first end of the first switch sub-switch 4031 is connected to the third end, the switch unit 403 also needs to connect the first voltage compensation unit 404 with the third end.
- the coil of the single normally closed contact switch where c4 is located is further controlled to flow current, so that c2 and c4 are not in contact, that is, the first end and the third end of the first switching sub-switch 4031 are disconnected, thereby breaking the circuit.
- the first group string 4011 and the first DC bus 405 are opened.
- the switch unit 403 may further include a second switch sub-switch 4032.
- the switch unit 403 controls the second switch sub-switch 4032 to connect to the power supply system according to the received voltage compensation enable signal.
- the second switch sub-switch 4032 can be a contact switch, including a first terminal, a second terminal and a third terminal.
- the second output terminal of a voltage compensation unit 404 is connected, and the third terminal is connected to the first DC bus 405 .
- the first switching sub-switch 4031 connecting the first voltage compensation unit 404 and the first string 4011
- the second switching sub-switch 4032 connecting the second string 4022 and the first DC bus 405
- the specific For the structure reference may be made to the description of the first switching sub-switch 4031 in FIGS. 5A to 5C , which will not be repeated here. It can be understood that, the first switching sub-switch 4031 and the second switching sub-switch 4032 may be integrated into one switching device, or may be set independently, and this embodiment does not limit the setting positions of the switching sub-switches.
- the first switching sub-switch 4031 and/or the second switching sub-switch 4032 can be implemented as any one of FIGS. 5A to 5C , and the first voltage compensation unit 404 is controlled to be connected to the first branch 401 and not connected to into the second branch 402 to achieve the beneficial effects described in FIG. 2 , which will not be repeated here.
- FIG. 6 is a schematic diagram of the system architecture of another power supply system provided by an embodiment of the present application.
- the power supply system in this embodiment may include a first branch 601 where the first group string 6011 is located, a second group The second branch 602 where the string 6022 is located, the switch unit 603 and the first voltage compensation unit 604.
- the switch unit 603 includes a first switch sub-switch 6031a between the first voltage compensation unit 604 and the first string 6011, and the switch unit 603 compensates according to the voltage received from the controller (not shown in the figure).
- the enable signal controls the first switching sub-switch 6031a to connect the first voltage compensation unit 604 with the first group string 6011 .
- the controller may be located in the photovoltaic inverter control module included in the power supply system of this embodiment.
- the controller generates the foregoing voltage compensation enable signal, which may be sent to the switch unit 603 , or sent to at least one processor, and the processor may forward the signal to the switch unit 603 .
- the first switching sub-switch 6031a may be a semiconductor switch, including a first terminal, a second terminal and a third terminal.
- the first end of the first switching sub-switch 6031a is connected to one end of the first group string 6011; the second end of the first switching sub-switch 6031a is connected to the second output end of the first voltage compensation unit 604; the first switching The third end of the sub-switch 6031a and the first output end of the first voltage compensation unit 604 are respectively connected to the first DC bus 605; the other end of the first string 6011 and the other end of the second string 6022 are respectively connected to the second DC bus 605 bus 606.
- the first switching sub-switch 6031a in this embodiment may include a first semiconductor switch and a second semiconductor switch as shown in FIG. 6 . semiconductor switch.
- the first semiconductor switch is Q1 for connecting the first voltage compensation unit 604 with the first string 6011 ;
- the second semiconductor switch is Q2 for disconnecting the first string 6011 and the first DC bus 605 .
- both the first semiconductor switch Q1 and the second semiconductor switch Q2 are MOSFETs.
- the source of the first semiconductor switch Q1 and the drain of the second semiconductor switch Q2 are respectively connected to the first terminal of the first switching sub-switch 6031a; the drain of the first semiconductor switch Q1 is connected to the second terminal of the first switching sub-switch 6031a,
- the source of the second semiconductor switch Q2 is connected to the third terminal of the first switching sub-switch 6031a.
- the switch unit 603 outputs a drive signal to the first semiconductor switch Q1 according to the received voltage compensation enable signal, and controls the first semiconductor switch Q1 to be turned on, thereby connecting the first voltage compensation unit 604 and the first group of strings 6011; and The output of the driving signal to the second semiconductor switch Q2 is stopped, and the second semiconductor switch Q2 is controlled to be turned off, thereby disconnecting the first group string 6011 and the first DC bus 605 .
- the semiconductor switch as the switch unit, compared with the contact switch, the volume of the power supply system can be reduced, and the on and off operations can be performed under the condition of high voltage and high current, which improves the safety of the system.
- the first switching sub-switch 6031a may include a third semiconductor switch and a diode as shown in FIG. 7 .
- the third semiconductor switch is Q5, which is used to connect the first voltage compensation unit 604 and the first group of strings 6011; the diode is D1, and the third semiconductor switch Q5 is used to connect the first voltage compensation unit 604 and the first group of strings 6011. In the case of reverse cut-off state, the first group string 6011 and the first DC bus 605 are disconnected.
- the source of the third semiconductor switch Q5 and the cathode of the diode D1 are respectively connected to the first terminal of the first switching sub-switch 6031a, the drain of the third semiconductor switch Q5 is connected to the second terminal of the first switching sub-switch 6031a, and the anode of the diode D1
- the third terminal of the first switch sub-switch 6031a is connected.
- the switch unit 603 outputs a driving signal to the third semiconductor switch Q5 according to the received voltage compensation enable signal, and controls the third semiconductor switch Q5 to be turned on, thereby connecting the first voltage compensation unit 604 and the first group of strings 6011.
- the specific implementation principle is: the third semiconductor switch Q5 is in the conducting state.
- the first DC bus 605 is the negative DC bus V-
- the first DC bus 605 is connected to the first DC bus 605
- the first output terminal of the voltage compensation unit 604 is a negative output terminal
- the second output terminal is a positive output terminal.
- the positive voltage output by the positive output terminal of the first voltage compensation unit 604 is applied to the first switching sub-switch 6031a through the third semiconductor switch Q5.
- the first terminal is the cathode terminal of the diode D1
- the negative voltage output from the negative output terminal of the first voltage compensation unit 604 is applied to the anode terminal of the diode D1, so that the diode D1 is turned off in the reverse direction, that is, the first string 6011 is connected to the first The DC bus 605 is disconnected.
- the system cost is further reduced relative to using two semiconductor switches.
- FIG. 8 is a schematic diagram of a system architecture of another power supply system provided by an embodiment of the present application.
- the first switching sub-switch 6031a is replaced with the first switching sub-switch 6031b shown in FIG. 8
- the first switching sub-switch 6031b includes a fourth semiconductor switch and a fifth semiconductor switch, the fourth switching sub-switch 6031b
- the semiconductor switch is Q6 and the fifth semiconductor switch is Q7.
- the drain of the fourth semiconductor switch Q6 and the source of the fifth semiconductor switch Q7 are respectively connected to the first terminal of the first switching sub-switch 6031b, and the source of the fourth semiconductor switch Q6 is connected to the second terminal of the first switching sub-switch 6031b, The drain of the fifth semiconductor switch Q7 is connected to the third terminal of the first switching sub-switch 6031b.
- the switch unit 603 outputs a drive signal to the fourth semiconductor switch Q6 according to the received voltage compensation enable signal, and controls the fourth semiconductor switch Q6 to be turned on, thereby connecting the first voltage compensation unit 604 and the first group of strings 6011; and The output of the driving signal to the fifth semiconductor switch Q7 is stopped, and the fifth semiconductor switch Q7 is controlled to be turned off, thereby disconnecting the first group string 6011 and the first DC bus 605 .
- the first switching sub-switch 6031b may include a sixth semiconductor switch and a diode as shown in FIG. 9 .
- the sixth semiconductor switch is Q10
- the diode is D2
- the drain of the sixth semiconductor switch Q10 and the anode of the diode D2 are respectively connected to the first end of the first switching sub-switch 6031b
- the source of the sixth semiconductor switch Q10 is connected to the first end of the first switching sub-switch 6031b.
- the second terminal of the switching sub-switch 6031b is connected, and the cathode of the diode D2 is connected to the third terminal of the first switching sub-switch 6031b.
- the switch unit 603 outputs a drive signal to the sixth semiconductor switch Q10 according to the received voltage compensation enable signal, and controls the sixth semiconductor switch Q10 to be turned on, thereby connecting the first voltage compensation unit 604 and the first group string 6011.
- the specific implementation principle is: the sixth semiconductor switch Q10 is in an on state, since the first DC bus 605 is a positive DC bus, the first voltage compensation unit connected to the first DC bus 605
- the first output terminal of 604 is a positive output terminal
- the second output terminal is a negative output terminal
- the negative voltage output by the negative output terminal of the first voltage compensation unit 604 is applied to the first switching sub-switch 6031b through the sixth semiconductor switch Q10.
- the first DC bus 605 can be adapted to two situations in which the first DC bus 605 is a positive DC bus or a negative DC bus, thereby improving the applicability of the power supply system.
- the switch unit 603 may further include a second switch sub-switch 6032a, and the switch unit 603 can compensate the voltage according to the received voltage.
- the power signal controls the second switching sub-switch 6032a to connect the first DC bus 605 and the second string 6022 in the power supply system.
- the second switch sub-switch 6032a may be a semiconductor switch, including a first terminal, a second terminal and a third terminal. The first terminal of the second switch sub-switch 6032a is connected to one end of the second string, and the second terminal is connected to the first voltage The second output terminal of the compensation unit 604 is connected, and the third terminal is connected to the first DC bus 605 .
- the second switching sub-switch 6032a connects the second string 6022 and the first DC bus 605, and the second switching sub-switch 6032a
- the description of the first switching sub-switch 6031a with reference to FIG. 6 to FIG. 7 , which will not be repeated here.
- the switch unit 603 may further include a second switch sub-switch 6032b, and the switch unit 603 enables compensation according to the received voltage. signal to control the second switching sub-switch 6032b to connect the first DC bus 605 with the second string 6022 .
- the second switch sub-switch 6032b may be a semiconductor switch, including a first terminal, a second terminal and a third terminal. The first terminal of the second switch sub-switch 6032b is connected to one end of the second string, and the second terminal is connected to the first The second output terminal of the voltage compensation unit 604 is connected, and the third terminal is connected to the first DC bus 605 .
- the second switching sub-switch 6032b connecting the second string 6022 and the first DC bus 605
- the specific For the structure reference may be made to the description of the first switching sub-switch 6031b in FIG. 8 to FIG. 9 , which will not be repeated here.
- the switch unit in the present application may include at least one contact switch and/or at least one semiconductor switch, that is, the specific structures of the first switch sub-switch and the second switch sub-switch may be different, for example, the first switch sub-switch and the second switch sub-switch may have different specific structures.
- One toggle sub-switch is a contact switch and the second toggle sub-switch is a semiconductor switch, or vice versa.
- the semiconductor switches Q1, Q2, Q3, Q4, etc. may be MOSFETs, or may be IGBTs and their anti-parallel diodes. 4 to 9, the MOSFET is used as an example. If Q1, Q2, Q3, Q4, etc. are IGBTs and their anti-parallel diodes, the source of the MOSFET is replaced with the emitter of the IGBT, and the drain of the MOSFET is replaced. It is the collector of the IGBT, the anode of the anti-parallel diode is connected to the emitter of the IGBT, and the cathode is connected to the collector of the IGBT.
- FIG. 10 is a schematic diagram of a system architecture of another power supply system provided by an embodiment of the present application.
- Each group string in this embodiment includes at least one DC component and a converter corresponding to the DC component, and the converter is used to adjust the working state of the corresponding DC component.
- the output end of the DC component 1-1 is connected to the input end of the converter 1-1
- the output end of the DC component 1-2 is connected to the input end of the converter 1-2
- the output end of the DC component 1-a The input ends of the converters 1-a are connected, and the output ends of the converters 1-1, 1-2...
- the two DC buses 1006 are connected, and the second output terminal of the converter 1-a is connected to the switch unit 1003, where a is not less than 1; similarly, the output terminal of the DC component 2-1 is connected to the input terminal of the converter 2-1 , the output end of the DC component 2-2 is connected to the input end of the converter 2-2, the output end of the DC component 2-b is connected to the input end of the converter 2-b, each converter 2-1, 2-2...2
- the output terminals of -b are sequentially connected in series to form a second group string 10022, the first output terminal of the converter 2-1 is connected to the second DC bus 1006, the second output terminal of the converter 2-b is connected to the switch unit 1003, where b is not less than 1.
- b can be the same as a or different from a.
- Each of the above-mentioned converters converts the input voltage into a constant voltage through buck-boost, that is, by using the converter to adjust the voltage of the DC components in the string, thereby optimizing the working state of the DC components.
- the first DC bus 1005 may be a negative DC bus or a positive DC bus.
- the first output terminal of the converter is a positive output terminal, and the second output terminal is a negative output terminal;
- the first DC bus 1005 is a positive DC bus, the first output terminal of the converter is a positive output terminal.
- One output terminal is a negative output terminal, and the second output terminal is a positive output terminal.
- the DC components can be photovoltaic modules, ie solar cell modules.
- the present application can also be applied in energy storage scenarios, that is, the DC component can be an energy storage battery, such as a nickel-cadmium battery, a nickel-metal hydride battery, a lithium-ion battery, a lithium-polymer battery, and the like.
- FIG. 11 is a schematic diagram of a system architecture of another power supply system provided by an embodiment of the present application.
- FIG. 11 takes the example that the first group string 1101 includes two sub-group strings 11011 and 11012 , which is not exhaustive, and should be understood as including but not limited to two sub-group strings. That is, the first group string 1101 may include at least two subgroup strings.
- the first substring 11011 and the second substring 11012 are connected in parallel to form the first string 1101, and the output voltage ranges corresponding to the maximum power points of the first substring 11011 and the second substring 11012 at least partially overlap.
- the voltage and power curve of the first substring 11011 can be the C curve in FIG. 12
- the voltage and power curve of the second substring 11012 can be the D curve in FIG. 12 .
- the first substring 11011 and the second substring The output voltage ranges corresponding to the respective maximum power points of 11012 overlap between 250V and 310V. At this time, it is considered that the first substring 11011 and the second substring 11012 have a high degree of adaptation.
- the maximum power point tracking (MPPT) control can be used to convert the first sub-string 11012.
- the output voltage of one substring 11011 is adjusted to 300V, or the output voltage of the second substring 11012 is adjusted to 280V through MPPT control, or the output voltage of the first substring 11011 is adjusted to 290V through MPPT control and the first substring 11011 is adjusted to 290V through MPPT control.
- the output voltage of the two sub-strings 11012 is adjusted to 290V and so on.
- MPPT control can be understood as continuously adjusting the output voltage of the target string according to the working environment of the target string (such as light intensity, ambient temperature, etc.), so that the target string can output the maximum power.
- the above-mentioned MPPT control is exemplified by adjusting the output voltage of the first substring 11011 and/or the second substring 11012 to be 300V, 280V or 290V, and is not exhaustive. That is, the output voltages of the first sub-string 11011 and the second sub-string 11012 can be adjusted to be the same through MPPT control, thereby sharing the first switching sub-switch 11031 and the first voltage compensation unit 1104 .
- the system cost can be further reduced by connecting the two subgroups with a higher degree of adaptation in series and parallel, and sharing a switch unit and a voltage compensation unit.
- the first sub-string 11011 and/or the second sub-string 11012 may include at least one DC component and a converter corresponding to the DC component.
- the implementation described above in conjunction with FIG. 10 For example, it will not be repeated here.
- the first DC bus 1105 may be a negative DC bus, and the second DC bus 1106 may be a positive DC bus; or the first DC bus 1105 may be a positive DC bus, and the second DC bus 1106 may be a negative DC bus.
- the second string 1102 may also include at least two substrings, and each substring shares the second switching sub-switch 11032 and the first voltage compensation unit 1104 . That is, each string in the power supply system may include at least two sub-strings, and not only one of the strings may include sub-strings.
- the number of sub-strings included in a string depends on whether the output voltage ranges corresponding to the maximum power points between the sub-strings overlap. If the output voltage ranges corresponding to the maximum power points overlap, they can be connected in parallel to share a voltage. Compensation unit and a toggle sub-switch.
- FIG. 13 is a schematic diagram of a system architecture of another power supply system provided by an embodiment of the present application.
- Fig. 13 is an example in which the power supply system includes three branches where three strings are located and two voltage compensation units, which is not exhaustive. It should be understood that the power supply system may include N branches where N strings are located and M Voltage compensation unit, N and M are both positive integers, and M is less than N. As shown in FIG.
- the power supply system in this embodiment may include a first branch 1301 where the first string 13011 is located, a second branch 1302 where the second string 13022 is located, and a third branch where the third string 13033 is located
- the switch unit 1304 may include a first switch sub-switch 13041 , a second switch sub-switch 13042 and a third switch sub-switch 13043 .
- Each switch sub-switch includes a first terminal, a second terminal and a third terminal, wherein the first terminal of the first switch sub-switch 13041 is connected to one end of the first group string 13011, and the second terminal of the first switch sub-switch 13041 is connected to The second output terminal of the first voltage compensation unit 1305 is connected, the third terminal of the first switching sub-switch 13041 and the first output terminal of the first voltage compensation unit 1305 are respectively connected to the first DC bus 1307; the second switching sub-switch The first end of 13042 is connected to one end of the second group string 13022, the second end of the second switch sub-switch 13042 is connected to the second output end of the second voltage compensation unit 1306, and the third end of the second switch sub-switch 13042 and The first output terminals of the second voltage compensation unit 1306 are respectively connected to the first DC bus 1307; the first terminal of the third switching sub-switch 13043 is connected to one terminal of the third string 13033, and the second switching The terminal is connected to
- the controller obtains the working state parameters of the first string 13011, the second string 13022 and the third string 13033, and generates voltage compensation according to the working state parameters of the first string 13011, the second string 13022 and the third string 13033 enable signal.
- the controller when the output voltages of the first string 13011 , the second string 13022 and the third string 13033 are different, the controller generates a voltage compensation enable signal, and sends the voltage compensation to the switch unit 1304 enable signal.
- the switch unit 1304 connects some or all of the voltage compensation units to some branches respectively according to the voltage compensation enable signal.
- the switch unit 1304 controls the first voltage compensation unit 1305 to connect to the first branch 1301, and the second voltage compensation unit 1306 to connect to the second branch 1302; or the output voltages of the first string 13011 and the third string 13033 are relatively small, the switch unit 1304 controls the first voltage compensation unit 1305 to be connected to the first branch 1301, and the second voltage compensation unit 1306 to be connected The third branch 1303; or the output voltages of the second string 13022 and the third string 13033 are relatively small, and the switch unit 1304 controls the second voltage compensation unit 1306 to access the second branch 1302 and the first voltage compensation unit 1305 Connect to the third branch 1303; or the output voltage of the first string 13011 is small, the switch unit 1304 controls the first voltage compensation unit 1305 to connect to the first branch 1301, and the second voltage compensation unit 1306 outputs the voltage can be zero; or the output voltage of the second group string 13022 is relatively small, the switch unit 1304 controls the second voltage compensation unit
- the voltage compensation unit By connecting the voltage compensation unit to the branch that needs voltage compensation, and not to the branch that does not need voltage compensation, the voltage compensation unit is not connected to avoid unnecessary voltage compensation units in the branch that does not need voltage compensation.
- System loss, and the number of voltage compensation units is less than the number of strings, compared with the number of voltage compensation units in the prior art equal to the number of strings, the number of voltage compensation units can be reduced and the system cost can be reduced.
- the first branch 1301 , the second branch 1302 and the third branch 1303 may not be connected to any voltage compensation unit in a default state.
- the above-mentioned controller can The working state parameters of the 2000 do not generate the voltage compensation enable signal or generate the voltage compensation default signal.
- the switch unit 1304 does not receive the voltage compensation enable signal or receives the voltage compensation default signal, it controls the voltage compensation unit not to connect to the first branch. Road 1301, second branch 1302 and third branch 1303.
- the controller of this embodiment may be provided in a photovoltaic inverter control module included in the power supply system.
- the above-mentioned controller can also determine at least one voltage compensation reference value according to the working state parameters of the first group string 13011, the second group string 13022 and the third group string 13033, and send the reference value to the first voltage compensation unit 1305 and the third group string respectively.
- the second voltage compensation unit 1306 sends the corresponding voltage compensation reference value, so that the first voltage compensation unit 1305 compensates the first branch 1301 or the third branch 1303 according to the received voltage compensation reference value, and the second voltage compensation unit 1306 compensates according to the received voltage compensation reference value.
- the received voltage compensation reference value compensates the second branch 1302 or the third branch 1303 .
- the output voltage value of the first group string 13011 is 200V
- the output voltage value of the second group string 13022 is 300V
- the output voltage value of the third group string 13033 is 250V
- the controller to the first voltage compensation unit The voltage compensation value sent by 1305 is 100V
- the voltage compensation value sent to the second voltage compensation unit 1306 is 50V.
- first switching sub-switch 13041 and the second switching sub-switch 13042 may refer to the embodiments described in FIGS. 4 to 9 , and details are not repeated here.
- the specific structure and specific implementation manner of the third switching sub-switch 13043 will be exemplarily described below with reference to FIGS. 14A to 15D .
- the third switch sub-switch 13043 may be a contact switch. Referring to Figures 14A-14B.
- the third switch sub-switch 13043 may include three single normally open contact switches as shown in FIG. 14A , each single normally open contact switch includes a static contact, a dynamic contact Contact and a coil, a single normally open contact switch can be understood as the default state when the static contact and the moving contact are disconnected.
- the moving contacts of the three single normally open contact switches are A1, A2 and A3 respectively, and the static contacts of the three single normally open contact switches are A4, A5 and A6 respectively.
- A1 , A2 and A3 are all connected to the first terminal of the third switch sub-switch 13043 .
- A4, A5 and A6 may be connected to any one of the fourth terminal, the second terminal or the third terminal of the third switching sub-switch 13043.
- the switch unit 1304 controls whether current flows through the coils of each single normally open contact switch to control whether each contact is in contact, thereby controlling whether each port of the third switch sub-switch 13043 is connected.
- A4 is connected to the fourth end of the third changeover sub-switch 13043
- A5 is connected to the second end of the third changeover sub-switch 13043
- A6 is connected to the third end of the third changeover sub-switch 13043.
- the changeover switch unit 1304 controls the A current flows through the coil where A5 is located, so that A2 and A5 are in contact, that is, the first end of the third switching sub-switch 13043 is connected to the second end, thereby connecting the first voltage compensation unit 1305 and the third group string 13033, the first voltage compensation unit 1305 is connected to the third branch 1303; or the switch unit 1304 controls the coil where A6 is located to flow current, so that A3 and A6 are in contact, that is, the first end of the third switch sub-switch 13043 is connected to the third end, thereby connecting the second voltage
- the compensation unit 1306 is connected to the third string 13033, and the second voltage compensation unit 1306 is connected to the third branch 1303; or the switch unit 1304 controls the coil where A4 is located to flow current, so that A1 and A4 are in contact, that is, the third switch sub-switch 13043
- the first end of the 1 is connected to the fourth end, so as to connect the third string 13033 and the first DC bus 13
- the third switch sub-switch 13043 may include a single normally closed contact switch and two single normally open contact switches as shown in FIG. 14B .
- Both the single normally open contact switch and the single normally closed contact switch include a static contact, a moving contact and a coil.
- the difference between the single normally closed contact switch and the single normally open contact switch is that the static contact and the moving contact of the single normally closed contact switch are in contact by default.
- the moving contact of the single normally closed contact switch is B1 and the static contact is B4; the moving contacts of the two single normally open contact switches are B2 and B3 respectively, and the static contacts are B5 and B6 respectively.
- B1, B2 and B3 are all connected to the first terminal of the third switch sub-switch 13043, and B4 is connected to the fourth terminal of the third switch sub-switch 13043.
- B1 and B4 are in contact, that is, the third switch sub-switch 13043 is in the In the default state, the first terminal is connected to the fourth terminal, connecting the third string 13033 and the first DC bus 1307, and the third branch 1303 is not connected to any voltage compensation unit.
- B5 and B6 can be connected to either the second terminal or the third terminal of the third switching sub-switch 13043 .
- the switch unit 1304 controls whether the coils of the single normally closed contact switch and the single normally open contact switch flow current to control whether the contacts are in contact, thereby controlling whether the port of the third switch sub-switch 13043 is connected. In this embodiment, it is connected with B5
- the second end of the third switch sub-switch 13043 and B6 are connected to the third end of the third switch sub-switch 13043 for example, the switch unit 1304 controls the coil where B5 is located to flow current, so that B2 and B5 are in contact, that is, the third switch sub-switch
- the first end of 13043 is connected to the second end, thereby connecting the first voltage compensation unit 1305 and the third group string 13033, the first voltage compensation unit 1305 is connected to the third branch 1303, and the switch unit 1304 also controls the coil where B4 is located.
- the switch unit 1304 controls the coil where B6 is located to flow current, so that B3 and B6 are in contact, that is, the first end of the third switch sub-switch 13043 is connected to the third end, thereby connecting the second voltage compensation unit 1306 and the third group string 13033 , the second voltage compensation unit 1306 is connected to the third branch 1303, and the switch unit 1304 also controls the coil where B4 is located to flow current, so that B1 and B4 are not in contact, that is, the first end of the third switch sub-switch 13043 is connected to the fourth The terminal is disconnected, thereby disconnecting the third group string 13033 from the first DC bus 1307 .
- the third switching sub-switch 13043 may be a semiconductor switch, refer to FIGS. 15A to 15D .
- the third switching sub-switch 13043 may include a seventh semiconductor switch, an eighth semiconductor switch, and a ninth semiconductor switch as shown in FIG. 15A .
- the seventh semiconductor switch is Q11, which is used to control the on-off between the first DC bus 1307 and the third group string 13033;
- the eighth semiconductor switch is formed by connecting Q14 and Q15 to the top, and is used to control the first voltage
- the ninth semiconductor is formed by connecting Q12 and Q13 on top of each other, and is used to control the on-off between the second voltage compensation unit 1306 and the third string 13033 .
- the source of Q14 is connected to the source of Q15, the source of Q12 is connected to the source of Q13, the drain of Q11, the drain of Q12 and the drain of Q14 are respectively connected to the first end of the third switching sub-switch 13043 , the source of Q11 is connected to the fourth terminal of the third switching sub-switch 13043 , the drain of Q13 is connected to the third terminal of the third switching sub-switch 13043 , and the drain of Q15 is connected to the second terminal of the third switching sub-switch 13043 .
- the source of Q11 is connected to the fourth terminal of the third switching sub-switch 13043
- the drain of Q13 is connected to the third terminal of the third switching sub-switch 13043
- the drain of Q15 is connected to the second terminal of the third switching sub-switch 13043 .
- the second terminal of the third switching sub-switch 13043 is connected to the first voltage compensation unit 1305, and the third terminal is connected to the second voltage compensation unit 1306.
- the relationship between the output voltages of the first voltage compensation unit 1305 and the second voltage compensation unit 1306 is uncertain, and the MOSFET has a parasitic diode or the IGBT has an anti-parallel diode.
- the second voltage compensation unit 1306 applies a voltage of 20V to the third
- the first terminal of the switch sub-switch 13043 is switched, and the second terminal of the third switch sub-switch 13043 is applied with a voltage of 10V by the first voltage compensation unit 1305, and the voltage between the first terminal and the second terminal of the third switch sub-switch 13043 is switched
- the difference can turn on the parasitic diode of Q15 so that the first voltage compensation unit 1305 is also connected to the third group string 13033 .
- the eighth semiconductor switch uses two MOSFETs to be connected to the top, and an inverse MOSFET, ie Q14, is added.
- the ninth semiconductor switch uses two MOSFETs to be connected to the top, adding a reverse MOSFET, that is, Q12.
- the switch unit 1304 can output a drive signal to Q14 and Q15 according to the voltage compensation enable signal, and connect the first voltage compensation unit 1305 and the third string 13033, that is, the first voltage compensation unit 1305 is connected to the third branch 1303; or Output the driving signal to Q12 and Q13 to connect the second voltage compensation unit 1306 with the third string 13033, that is, the second voltage compensation unit 1306 is connected to the third branch 1303; or output the driving signal to Q11 to connect the first DC bus 1307 and the third string 13033, that is, the third branch 1303 is not connected to any voltage compensation unit.
- the third switching sub-switch 13043 may include a tenth semiconductor switch, an eleventh semiconductor switch and a diode as shown in FIG. 15B .
- the diode is D3, which is used to control the on-off between the first DC bus 1307 and the third group string 13033; the tenth semiconductor switch is formed by connecting Q18 and Q19 on top of each other, and is used to control the first voltage compensation unit 1305 On-off between the third string 13033; the eleventh semiconductor switch is formed by connecting Q16 and Q17 to the top, and is used to control the on-off between the second voltage compensation unit 1306 and the third string 13033, Fig.
- the reason for adding the reverse series MOSFETs Q18 and Q16 in 15B can refer to the description of Q14 and Q12 in FIG. 15A, and will not be repeated here.
- the source of Q18 is connected to the source of Q19
- the source of Q16 is connected to the source of Q17
- the cathode of diode D3 the drain of Q16 and the drain of Q18 are respectively connected to the first end of the third switching sub-switch 13043
- the anode of diode D3 is connected to the fourth terminal of the third switch sub-switch 13043
- the drain of Q17 is connected to the third terminal of the third switch sub-switch 13043
- the drain of Q19 is connected to the second terminal of the third switch sub-switch 13043 .
- the switch unit 1304 can output driving signals to Q18 and Q19 according to the voltage compensation enable signal, and connect the first voltage compensation unit 1305 with the third string 13033, that is, the first voltage compensation unit 1305 is connected to the third branch 1303; or
- the driving signal is output to Q16 and Q17 to connect the second voltage compensation unit 1306 and the third group string 13033 , that is, the second voltage compensation unit 1306 is connected to the third branch 1303 .
- the diode D3 is in a reverse cut-off state when the first voltage compensation unit 1305 is connected to the third branch 1303, or the second voltage compensation unit 1306 is connected to the third branch 1303, thereby disconnecting the third string 13033 from the first
- the specific implementation principle may refer to the embodiment described above in conjunction with FIG. 7, and will not be repeated here.
- the third switching sub-switch 13043 may include a twelfth semiconductor switch, a thirteenth semiconductor switch, and a fourteenth semiconductor switch as shown in FIG. 15C semiconductor switch.
- the twelfth semiconductor switch is Q20, which is used to control the on-off between the first DC bus 1307 and the third group string 13033; the thirteenth semiconductor switch is formed by connecting Q23 and Q24 to the top, and is used to control the first DC bus 1307 and the third group string 13033.
- the on-off between a voltage compensation unit 1305 and the third string 13033; the fourteenth semiconductor is formed by connecting Q21 and Q22 on top of each other, and is used to control the voltage between the second voltage compensation unit 1306 and the third string 13033 on and off.
- the source of Q23 is connected to the source of Q24, the source of Q21 is connected to the source of Q22, the source of Q20, the drain of Q21 and the drain of Q23 are respectively connected to the first end of the third switching sub-switch 13043 , the drain of Q20 is connected to the fourth terminal of the third switching sub-switch 13043 , the drain of Q22 is connected to the third terminal of the third switching sub-switch 13043 , and the drain of Q24 is connected to the second terminal of the third switching sub-switch 13043 .
- the switch unit 1304 can output a drive signal to Q23 and Q24 according to the voltage compensation enable signal, and connect the first voltage compensation unit 1305 and the third string 13033, that is, the first voltage compensation unit 1305 is connected to the third branch 1303; or Output the driving signal to Q21 and Q22 to connect the second voltage compensation unit 1306 and the third group string 13033, that is, the second voltage compensation unit 1306 is connected to the third branch 1303; or output the driving signal to Q20 to connect the first DC bus 1307 and the third string 13033, that is, the third branch 1203 is not connected to any voltage compensation unit.
- the third switching sub-switch 13043 may include a fifteenth semiconductor switch, a sixteenth semiconductor switch and a diode as shown in FIG. 15D .
- the diode is D4, which is used to control the on-off between the first DC bus 1307 and the third group string 13033;
- the fifteenth semiconductor switch is formed by connecting Q27 and Q28 on top of each other, and is used to control the first voltage compensation unit On-off between 1305 and the third string 13033;
- the sixteenth semiconductor is formed by connecting Q25 and Q26 to the top, and is used to control the on-off between the second voltage compensation unit 1306 and the third string 13033.
- the source of Q27 is connected to the source of Q28, the source of Q25 is connected to the source of Q26, the anode of diode D4, the drain of Q27 and the drain of Q25 are respectively connected to the first end of the third switching sub-switch 13043 , the cathode of diode D4 is connected to the fourth terminal of the third switch sub-switch 13043 , the drain of Q26 is connected to the third terminal of the third switch sub-switch 13043 , and the drain of Q28 is connected to the second terminal of the third switch sub-switch 13043 .
- the switch unit 1304 can output drive signals to Q27 and Q28 according to the voltage compensation enable signal, and connect the first voltage compensation unit 1305 and the third group string 13033, that is, the first voltage compensation unit 1305 is connected to the third branch 1303; or The driving signals are output to Q25 and Q26 to connect the second voltage compensation unit 1306 and the third group string 13033 , that is, the second voltage compensation unit 1306 is connected to the third branch 1303 .
- the diode D4 is in a reverse cut-off state when the first voltage compensation unit 1305 is connected to the third branch 1303, or the second voltage compensation unit 1306 is connected to the third branch 1303, thereby disconnecting the third group string 13033 from the first direct line.
- the specific implementation principle may refer to the embodiment described above in conjunction with FIG. 9, and will not be repeated here.
- the switch unit 1304 may include N switch sub-switches between the string and the voltage compensation unit, for example, a first switch sub-switch, a second switch sub-switch...
- the N-1th switch sub-switch includes three terminals, which are respectively used to switch The first group string, the second group string...the N-1th string is connected to the voltage compensation unit or the DC bus, and the Nth switch sub-switch selectively connects the Nth string to any voltage compensation unit or the DC bus , that is, the Nth switch sub-switch needs to include M+2 terminal, where the M terminal is used to select any one of the M voltage compensation units, one of the remaining two ends is used to connect the Nth group string, and the other terminal is Used to connect the DC bus.
- the first group string 13011, the second group string 13022, and the third group string 13033 may include at least one DC component and a converter.
- first group string 13011, the second group string 13022, and the third group string 13033 may be combined with the embodiments described in FIG. 11, and at least one group string may include at least two subgroup strings.
- the switch unit 1304 in the present application may include at least one contact switch and/or at least one semiconductor switch, namely the first switch sub-switch 13041 , the second switch sub-switch 13042 and the third switch sub-switch 13042 .
- the specific structure of the switch 13043 may be different, for example, the first switching sub-switch 13041 is a contact switch, the second switching sub-switch 13042 is a contact switch, and the third switching sub-switch 13043 is a semiconductor switch; or the first switching sub-switch 13041 is a contact switch, the second switching sub-switch 13042 is a semiconductor switch, and the third switching sub-switch 13043 is a contact switch and so on.
- Q11, Q12, Q13, Q14, etc. in the semiconductor switch may be MOSFETs, or may be IGBTs and their anti-parallel diodes.
- 15A to 15D are used as an example to illustrate the description. If Q11, Q12, Q13, Q14, etc. are IGBTs and their anti-parallel diodes, the source of the MOSFET is replaced with the emitter of the IGBT, and the drain of the MOSFET is replaced It is the collector of the IGBT, the anode of the anti-parallel diode is connected to the emitter of the IGBT, and the cathode is connected to the collector of the IGBT.
- An embodiment of the present application further provides a string compensation method, which is applied to any of the power supply systems described above.
- the power supply system includes a first branch where the first string is located, and a second branch where the second string is located.
- a branch circuit, a first voltage compensation unit and a controller, the method includes the following steps:
- the switch unit receives a voltage compensation enable signal from the controller, connects the first voltage compensation unit to the first branch according to the voltage compensation enable signal, and the voltage compensation enable signal is based on the working state parameters of the first group string and the working state parameters of the second group of strings; the first voltage compensation unit is used for compensating the output voltage of the first branch.
- the switch unit is located in the above-mentioned power supply system.
- the working state parameter of the group string may be the output voltage, and/or the output current, and/or the output power, etc. of the group string, and the present application takes the output voltage as an example for description.
- the controller obtains the operating state parameters of the first group string and the second group string, and generates a voltage compensation enable according to the operating state parameter of the first group string and the operating state parameter of the second group string Signal. For example, when the output voltages of the first string and the second string are different, for example, the output voltage of the first string is small, the controller can generate a voltage compensation enable signal and send the signal to the switch unit. The voltage compensation enable signal is sent, and when the switch unit receives the voltage compensation enable signal, the switch unit controls the first voltage compensation unit to access the first branch.
- the first voltage compensation unit is only connected to the first branch that needs voltage compensation, and the second branch that does not need voltage compensation is not connected to the first voltage compensation unit, so as to avoid the voltage compensation unit in the second branch.
- the first voltage compensation unit is only connected to the first branch that needs voltage compensation
- the second branch that does not need voltage compensation is not connected to the first voltage compensation unit, so as to avoid the voltage compensation unit in the second branch.
- the power supply system further includes a first DC bus and a second DC bus;
- the first voltage compensation unit includes a first output terminal and a second output terminal, wherein the first output terminal is connected to the first DC bus;
- a switch The unit connects the first voltage compensation unit to the first branch according to the voltage compensation enable signal.
- the switching unit connects the second output end of the first voltage compensation unit to the first branch according to the voltage compensation enable signal.
- One end of the group string; the other end of the first group string is connected to the second DC bus.
- the first DC bus is a negative DC bus
- the first output terminal of the first voltage compensation unit is a negative output terminal
- the second output terminal is a positive output terminal
- the first DC bus is a positive DC bus
- the The first output terminal of the first voltage compensation unit is a positive output terminal
- the second output terminal is a negative output terminal.
- the switch unit and the first voltage compensation unit can be arranged on either the positive DC bus side or the negative DC bus side, The applicability of the power supply system can be improved.
- the switch unit also connects one end of the second group of strings to the first DC bus according to the voltage compensation enable signal; the other end of the second group of strings is connected to the second DC bus.
- the first voltage compensation unit is neither connected to the first branch nor the second branch.
- the controller may not generate a voltage compensation enable according to the operating state parameters of the first group string and the operating state parameters of the second group string signal or generate a voltage compensation default signal, when the switch unit does not receive the voltage compensation enable signal or receives the voltage compensation default signal, controls the first voltage compensation unit to neither access the first branch nor the second branch road.
- the power supply system is applied to photovoltaics
- the first string and the second string are photovoltaic strings
- the controller may be provided in a photovoltaic inverter control module in the power supply system.
- the first group string and the second group string of the power supply system are respectively provided with a processor, the processor can collect the working state parameters of the corresponding group strings, and summarize the collected working state parameters into
- the processor that obtains the working state parameters of all the strings is the above-mentioned controller.
- the controller may further determine a voltage compensation reference value according to the working state parameters of the first string and the working state parameters of the second string, and send the reference value to the first voltage compensation unit.
- the voltage compensation reference value enables the first voltage compensation unit to compensate the output voltage of the first branch according to the voltage compensation reference value, that is, the voltage compensation reference value is the output voltage value of the first voltage compensation unit.
- the switch unit includes a first switch sub-switch between the first voltage compensation unit and the first group of strings, and the first switch sub-switch is a contact switch or a semiconductor switch.
- the above-mentioned switching unit for connecting the first voltage compensation unit to the first branch according to the voltage compensation enable signal is specifically implemented as follows: the switch unit controls the first switch sub-switch to connect to the first voltage compensation according to the voltage compensation enable signal unit with the first set of strings.
- the first switching sub-switch includes a first semiconductor switch and a second semiconductor switch, wherein the first semiconductor switch is used for connecting the first voltage compensation unit and the first group string, and the second semiconductor switch is used for disconnecting the second semiconductor switch
- a group of strings is connected to the first DC bus in the power supply system.
- the switch unit according to the voltage compensation enable signal, controls the first switch sub-switch to connect the first voltage compensation unit and the first group of strings.
- the voltage compensation unit is connected to the first string, and controls the second semiconductor switch to disconnect the first string and the first DC bus.
- the first switching sub-switch includes a third semiconductor switch and a diode, wherein the third semiconductor switch is used to connect the first voltage compensation unit and the first group string, and the diode is connected to the first voltage compensation unit at the third semiconductor switch In the case of the first group string, it is in a reverse cut-off state, thereby disconnecting the first group string and the first DC bus in the power supply system.
- the switch unit controls the first switch sub-switch to connect the first voltage compensation unit and the first group string.
- the three-semiconductor switch connects the first voltage compensation unit and the first group of strings, and disconnects the first group of strings from the first DC bus.
- the switch unit further includes a second switch sub-switch; the switch unit also controls the second switch sub-switch to connect to the first DC bus in the power supply system according to the voltage compensation enable signal with the second set of strings.
- the above-mentioned controller can re-configure according to the working state parameters between the strings.
- the first group string is determined, that is, the group string that needs voltage compensation is re-determined.
- the controller may first control the output voltage value of the first voltage compensation unit to be equal to or lower than a preset value before turning off the switch unit. Threshold value, and then control the switch unit to turn off, the preset threshold value is determined by the model of the contact switch.
- the power supply system includes N branches where N groups of strings are located and M voltage compensation units, where N and M are both positive integers, and M is less than N; the N branches include the th A branch and a second branch, the M voltage compensation units include a first voltage compensation unit.
- the switch unit may further connect some or all of the voltage compensation units to some of the branches according to the voltage compensation enable signal.
- each string includes at least one DC component and a converter corresponding to the DC component; the controller controls the converter to adjust the working state of the corresponding DC component.
- the converter may be a buck circuit or a boost circuit, and the controller adjusts the working state of the DC component by controlling the magnitude of the output voltage of the converter.
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Abstract
Description
Claims (23)
- 一种供电系统,其特征在于,包括:第一组串所在的第一支路、第二组串所在的第二支路、切换开关单元、第一电压补偿单元以及控制器;所述切换开关单元,用于根据从所述控制器接收到的电压补偿使能信号,将所述第一电压补偿单元接入所述第一支路;所述电压补偿使能信号是所述控制器根据第一组串的工作状态参数以及第二组串的工作状态参数生成的;所述第一电压补偿单元,用于对所述第一支路的输出电压进行补偿。
- 如权利要求1所述的供电系统,其特征在于,所述供电系统还包括第一直流总线和第二直流总线;所述第一电压补偿单元包括第一输出端以及第二输出端,所述第一电压补偿单元的第一输出端连接至所述第一直流总线;所述切换开关单元,用于根据所述电压补偿使能信号,将所述第一电压补偿单元的第二输出端连接至所述第一组串的一端;所述第一组串的另一端连接至所述第二直流总线。
- 如权利要求2所述的供电系统,其特征在于,所述切换开关单元,还用于根据所述电压补偿使能信号,将所述第二组串的一端连接至所述第一直流总线;所述第二组串的另一端连接至所述第二直流总线。
- 如权利要求2-3任一项所述的供电系统,其特征在于,所述第一电压补偿单元还包括第一输入端和第二输入端;所述第一电压补偿单元的第一输入端连接至所述第一直流总线,所述第一电压补偿单元的第二输入端连接至所述第二直流总线。
- 如权利要求1-4任一项所述的供电系统,其特征在于,所述第一组串包括至少两个子组串。
- 如权利要求5所述的供电系统,其特征在于,所述第一组串中包括的至少两个子组串各自最大功率点所对应的输出电压区间至少部分重合。
- 如权利要求1-6任一项所述的供电系统,其特征在于,所述切换开关单元包括所述第一电压补偿单元与所述第一组串之间的第一切换子开关,所述第一切换子开关为触点开关或半导体开关;所述切换开关单元,用于根据所述电压补偿使能信号,控制所述第一切换子开关连通所述第一电压补偿单元与所述第一组串。
- 如权利要求7所述的供电系统,其特征在于,所述切换开关单元还包括第二切换子 开关;所述切换开关单元,还用于根据所述电压补偿使能信号,控制所述第二切换子开关连通所述供电系统中的第一直流总线与所述第二组串。
- 如权利要求7所述的供电系统,其特征在于,所述第一切换子开关包括第一半导体开关和第二半导体开关,其中所述第一半导体开关用于连通所述第一电压补偿单元与所述第一组串,所述第二半导体开关用于断开所述第一组串与所述供电系统中的第一直流总线;所述切换开关单元,用于根据所述电压补偿使能信号,控制所述第一半导体开关连通所述第一电压补偿单元与所述第一组串,并控制所述第二半导体开关断开所述第一组串与所述第一直流总线。
- 如权利要求7所述的供电系统,其特征在于,所述第一切换子开关包括第三半导体开关和二极管,其中所述第三半导体开关用于连通所述第一电压补偿单元与所述第一组串,所述二极管在所述第三半导体开关连通所述第一电压补偿单元与所述第一组串的情况下处于反向截止状态,从而用于断开所述第一组串与所述供电系统中的第一直流总线;所述切换开关单元,用于根据所述电压补偿使能信号,控制所述第三半导体开关连通所述第一电压补偿单元与所述第一组串,并使得所述第一组串与所述第一直流总线断开。
- 如权利要求1-10任一项所述的供电系统,其特征在于,所述第一电压补偿单元包括非隔离型降压式变换电路。
- 如权利要求1-11任一项所述的供电系统,其特征在于,所述供电系统包括N个组串所在的N个支路以及M个电压补偿单元,N和M均为正整数,且M小于N;所述N个支路包括所述第一支路和所述第二支路,所述M个电压补偿单元包括所述第一电压补偿单元;所述切换开关单元,用于根据所述电压补偿使能信号,将部分或全部的电压补偿单元分别接入部分支路。
- 如权利要求1-12任一项所述的供电系统,其特征在于,每个组串包括至少一个直流组件以及与直流组件对应的变换器,所述变换器用于调节所述对应直流组件的工作状态。
- 如权利要求1-13任一项所述的供电系统,其特征在于,所述第一组串和所述第二组串为光伏组串。
- 一种供电方法,应用于供电系统,其特征在于,所述供电系统包括第一组串所在的第一支路、第二组串所在的第二支路、第一电压补偿单元以及控制器,所述方法包括:从所述控制器接收电压补偿使能信号,根据所述电压补偿使能信号将所述第一电压补偿单元接入所述第一支路;所述电压补偿使能信号是所述控制器根据第一组串的工作状态 参数以及第二组串的工作状态参数生成的;所述第一电压补偿单元,用于对所述第一支路的输出电压进行补偿。
- 如权利要求15所述的方法,其特征在于,所述供电系统还包括第一直流总线和第二直流总线;所述第一电压补偿单元包括第一输出端以及第二输出端,所述第一电压补偿单元的第一输出端连接至所述第一直流总线;所述根据所述电压补偿使能信号将所述第一电压补偿单元接入所述第一支路包括:根据所述电压补偿使能信号,将所述第一电压补偿单元的第二输出端连接至所述第一组串的一端;所述第一组串的另一端连接至所述第二直流总线。
- 如权利要求16所述的方法,其特征在于,所述方法还包括:根据所述电压补偿使能信号,将所述第二组串的一端连接至所述第一直流总线;所述第二组串的另一端连接至所述第二直流总线。
- 如权利要求15-17任一项所述的方法,其特征在于,所述切换开关单元包括所述第一电压补偿单元与所述第一组串之间的第一切换子开关,所述第一切换子开关为触点开关或半导体开关;所述根据所述电压补偿使能信号将所述第一电压补偿单元接入所述第一支路包括:根据所述电压补偿使能信号,控制所述第一切换子开关连通所述第一电压补偿单元与所述第一组串。
- 如权利要求18所述的方法,其特征在于,所述切换开关单元还包括第二切换子开关;所述方法还包括:根据所述电压补偿使能信号,控制所述第二切换子开关连通所述供电系统中的第一直流总线与所述第二组串。
- 如权利要求18所述的方法,其特征在于,所述第一切换子开关包括第一半导体开关和第二半导体开关;所述根据所述电压补偿使能信号,控制所述第一切换子开关连通所述第一电压补偿单元与所述第一组串包括:根据所述电压补偿使能信号,控制所述第一半导体开关连通所述第一电压补偿单元与所述第一组串,并控制所述第二半导体开关断开所述第一组串与所述第一直流总线。
- 如权利要求18所述的方法,其特征在于,所述第一切换子开关包括第三半导体开关和二极管;所述根据所述电压补偿使能信号,控制所述第一切换子开关连通所述第一电压补偿单元与所述第一组串包括:根据所述电压补偿使能信号,控制所述第三半导体开关连通所述第一电压补偿单元与所述第一组串,并使所述二极管处于反向截止状态,从而断开所述第一组串与所述第一直流总线。
- 如权利要求15-21任一项所述的方法,其特征在于,所述供电系统包括N个组串所在的N个支路以及M个电压补偿单元,N和M均为正整数,且M小于N;所述N个支路包括所述第一支路和所述第二支路,所述M个电压补偿单元包括所述第一电压补偿单元;所述方法还包括:根据所述电压补偿使能信号,将部分或全部的电压补偿单元分别接入部分支路。
- 如权利要求15-22任一项所述的方法,其特征在于,每个组串包括至少一个直流组件以及与直流组件对应的变换器;所述控制器,还用于控制所述变换器对所述对应直流组件的工作状态进行调节。
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Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH06296333A (ja) * | 1993-04-07 | 1994-10-21 | Mitsubishi Electric Corp | 宇宙船の電源装置 |
CN201947013U (zh) * | 2011-01-14 | 2011-08-24 | 宁波海锂子新能源有限公司 | 压差补偿均衡电源管理系统 |
CN105680794A (zh) * | 2016-04-12 | 2016-06-15 | 常熟市福莱德连接器科技有限公司 | 电压补偿法增效型光伏汇流箱 |
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Publication number | Priority date | Publication date | Assignee | Title |
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KR101226628B1 (ko) * | 2011-03-25 | 2013-01-28 | 주식회사 디케이 | 태양광 발전시스템의 직렬전압 보상장치 |
US9368965B2 (en) * | 2011-07-28 | 2016-06-14 | Tigo Energy, Inc. | Enhanced system and method for string-balancing |
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EP3433914B1 (en) * | 2016-05-09 | 2022-04-06 | Solaredge Technologies Ltd. | Maximizing power in a photovoltaic distributed power system |
CN106941263B (zh) * | 2017-04-24 | 2019-04-23 | 浙江大学 | 一种可以实现分布式mppt的集中式光伏发电系统 |
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CN207637040U (zh) * | 2017-12-28 | 2018-07-20 | 辽宁太阳能研究应用有限公司 | 一种光伏阵列智能电压补偿器 |
CN107885274B (zh) * | 2017-12-28 | 2023-05-16 | 辽宁太阳能研究应用有限公司 | 一种光伏阵列智能电压补偿器 |
CN111555443B (zh) * | 2020-04-20 | 2022-05-17 | 南京南瑞继保电气有限公司 | 模块化串联同步补偿系统及其控制方法 |
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Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH06296333A (ja) * | 1993-04-07 | 1994-10-21 | Mitsubishi Electric Corp | 宇宙船の電源装置 |
CN201947013U (zh) * | 2011-01-14 | 2011-08-24 | 宁波海锂子新能源有限公司 | 压差补偿均衡电源管理系统 |
CN105680794A (zh) * | 2016-04-12 | 2016-06-15 | 常熟市福莱德连接器科技有限公司 | 电压补偿法增效型光伏汇流箱 |
Non-Patent Citations (1)
Title |
---|
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