WO2022226956A1 - 一种光储系统、电源系统及高电压穿越控制方法 - Google Patents

一种光储系统、电源系统及高电压穿越控制方法 Download PDF

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Publication number
WO2022226956A1
WO2022226956A1 PCT/CN2021/091257 CN2021091257W WO2022226956A1 WO 2022226956 A1 WO2022226956 A1 WO 2022226956A1 CN 2021091257 W CN2021091257 W CN 2021091257W WO 2022226956 A1 WO2022226956 A1 WO 2022226956A1
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WIPO (PCT)
Prior art keywords
energy storage
storage device
inverter
high voltage
working state
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PCT/CN2021/091257
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English (en)
French (fr)
Inventor
肖刚
吴志清
武荣
朱琳
钟少辉
Original Assignee
华为数字能源技术有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
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Application filed by 华为数字能源技术有限公司 filed Critical 华为数字能源技术有限公司
Priority to EP21938434.4A priority Critical patent/EP4322358A4/en
Priority to CN202180065399.XA priority patent/CN116250157A/zh
Priority to PCT/CN2021/091257 priority patent/WO2022226956A1/zh
Publication of WO2022226956A1 publication Critical patent/WO2022226956A1/zh
Priority to US18/495,084 priority patent/US20240063654A1/en

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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
    • H02J3/00—Circuit arrangements for ac mains or ac distribution networks
    • H02J3/28—Arrangements for balancing of the load in a network by storage of energy
    • H02J3/32—Arrangements for balancing of the load in a network by storage of energy using batteries with converting means
    • 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
    • H02J3/00—Circuit arrangements for ac mains or ac distribution networks
    • H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
    • 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
    • H02J2300/24—The renewable source being solar energy of photovoltaic origin

Definitions

  • the present application relates to the technical field of photovoltaic power generation, and in particular, to an optical storage system, a power supply system and a high voltage ride-through control method.
  • photovoltaic power generation converts solar energy into electrical energy.
  • power generation and energy storage are currently combined to form a photovoltaic storage system.
  • Optical storage systems generally include photovoltaic arrays, direct current/direct current (DC/DC, Direct Current/Direct Current) converters, inverters (DC/AC, Direct Current/alternating Current) and energy storage equipment; DC/DC converters
  • DC/DC direct current/direct current
  • DC/AC Direct Current/alternating Current
  • the output terminal of the inverter is connected to the DC bus, the input terminal of the inverter is connected to the DC bus, and the energy storage device is connected to the DC bus.
  • the output end of the inverter is connected to the AC grid.
  • the application provides an optical storage system, a power supply system and a control method, which can control the energy storage equipment to work normally when a high voltage ride-through occurs in an AC power grid.
  • the embodiment of the present application provides an optical storage system, which is applied to a scenario of photovoltaic power generation and an energy storage device, that is, includes an inverter and an energy storage device; the input end of the inverter is used to connect the DC bus, and the The output terminal is used to connect the AC power grid; the DC bus is connected to the PV strings, and the PV strings provide DC power to the DC bus; the energy storage device is used to connect the DC bus, and the energy storage device can not only absorb energy from the DC bus to charge itself, but also to the DC bus.
  • the DC bus releases energy to achieve discharge; the inverter sends high-voltage ride-through information to the energy storage device when the voltage of the AC grid occurs high-voltage ride-through; when the energy storage device receives the high-voltage ride-through information, it takes measures according to its own working status Specifically: if the energy storage device is in the discharging working state, adjust the output voltage reference value to maintain the discharging working state; if the energy storage device is in the charging working state, adjust the charging power reference value to maintain the charging working state.
  • the inverter is used to identify whether the voltage of the AC power grid has high voltage ride-through.
  • the inverter recognizes the high voltage ride-through of the AC power grid, it notifies the energy storage device so that the energy storage device can take corresponding measures.
  • the energy storage device if the energy storage device is in the discharge working state, adjust the output voltage reference value to maintain the discharge working state, so as to prevent the high voltage fluctuating on the DC bus from back-feeding energy to the energy storage device.
  • the reference value of the charging power is adjusted to maintain the charging working state, so that the inverter can control the grid-connected current to meet the standard requirements of the grid during high voltage ride-through.
  • the optical storage system controls the energy storage device to maintain the original working state when high voltage ride-through occurs in the AC power grid, so as to avoid frequent switching of the working state due to high voltage ride-through, which may cause damage to the device.
  • the general energy storage device determines whether the high voltage ride through occurs by identifying the voltage of the DC bus, but when the high voltage ride through occurs in the AC grid, the voltage rise of the DC bus is related to the DC bus capacitance. It is related to the size of the energy storage device, and the energy storage device cannot accurately judge whether a high voltage ride through occurs through the voltage rise of the DC bus.
  • the inverter can identify the high voltage ride-through and can more accurately determine the time of the high voltage ride-through.
  • the energy storage device includes: a controller, a power conversion circuit, and a battery pack; the first end of the power conversion circuit is connected to the battery pack, and the second end of the power conversion circuit is connected to the DC bus; the power conversion circuit for
  • the controller is used to receive the HVRT information and the battery pack is in discharge working state, the energy storage device outputs energy to the DC bus, and controls the power conversion circuit to increase the output voltage reference value of the energy storage device to above the peak voltage of the HVRT, so that the The energy storage device continues to be in the discharge working state; the voltage of the DC bus can be quickly increased to continue to maintain the discharge working state, so as to prevent the voltage of the DC bus from being too high, and back-feeding the energy storage device to charge the battery pack in the energy storage device.
  • the purpose of the energy storage device to raise the voltage of the DC bus is to keep the energy storage device in the same discharge working state, and not frequently switch the working state between discharge and charging, and when the high voltage ride-through is satisfied, the inverter can follow the Standard requires output power.
  • the controller is also used to receive the high voltage ride-through information and the battery pack is in the charging working state, and adjust the charging power reference value of the energy storage device to the charging power before the high voltage ride-through, so that the energy storage device continues to be in the charging working state.
  • the energy storage device changes its working state when the AC power grid has high voltage ride-through, it will affect the inverter's control of the grid-connected current, so that the high voltage ride-through cannot be smoothly passed, and the normal operation of the energy storage device and the inverter will be affected. May cause damage to hardware devices.
  • the inverter is specifically configured to encode the high voltage ride through information into a pulse signal, and send the pulse signal to the first interface of the energy storage device through its own I/O port.
  • the high-voltage ride-through information sent by the inverter to the energy storage device may be a level-encoded signal, for example, the high-voltage ride-through information is encoded into a pulse signal, and the pulse signal is sent to the energy storage device.
  • the high voltage ride-through information can also be encoded into high and low level signals, and the high and low level signals are sent to the energy storage device, for example, a high level signal indicates that a high voltage ride through occurs.
  • the interface for sending the high voltage ride-through information of the inverter and the interface for sending the power-on signal share the same interface.
  • the energy storage system further includes: an energy storage drive circuit; an inverter, which is also used to send a power-on signal to the first interface of the energy storage drive circuit through the I/O port; The energy storage device is turned on.
  • the inverter in order to better isolate the direct signal interference between the inverter and the energy storage device, includes: a first optocoupler and a second optocoupler; a first optocoupler The first input end of the optocoupler is connected to the I/O port of the inverter, the first output end of the first optocoupler is connected to the power supply, and the second output end of the first optocoupler is connected to the first interface of the energy storage device; The first input end of the second optocoupler is connected to the I/O port of the inverter, and the output end of the second optocoupler is connected to the first interface of the energy storage drive circuit; the second input end of the first optocoupler is connected to the first interface of the energy storage drive circuit; The second input ends of the two optocouplers are both connected to the reference ground.
  • it further includes: a DC/DC converter; the input end of the DC/DC converter is used for connecting the photovoltaic string; the output end of the DC/DC converter is used for connecting the DC bus.
  • the DC/DC converter can convert the output voltage of the photovoltaic string into a voltage matched by the DC bus.
  • the embodiments of the present application do not limit the specific implementation form of the DC/DC converter, which may be a booster circuit or a buck-boost circuit. .
  • the embodiments of the present application do not specifically limit the number of photovoltaic strings, and generally, the input end of the DC/DC converter is connected to a plurality of photovoltaic strings.
  • the embodiments of the present application also do not specifically limit the number of DC/DC converters connected to the DC bus, which may be multiple.
  • the controller is specifically configured to control the output voltage reference value of the power conversion circuit to a preset multiple of the rated voltage of the AC power grid, and the value interval of the preset multiple is greater than 1.4 and less than 2.
  • Embodiments of the present application further provide a power supply system, including: an inverter and an energy storage device; an input end of the inverter is connected to a DC bus, an output end of the inverter is used to connect to an AC power grid; the energy storage device is connected to the DC bus; The inverter is used to send high-voltage ride-through information to the energy storage device when the voltage of the AC grid has high-voltage ride-through; The output voltage reference value is adjusted to maintain the discharge working state, and if the energy storage device is in the charging working state, the charging power reference value is adjusted to maintain the charging working state.
  • the inverter is specifically configured to encode the high voltage ride through information into a pulse signal, and send the pulse signal to the first interface of the energy storage device through its own I/O port.
  • the inverter is further configured to send a power-on signal to the second interface of the energy storage device through the I/O port; the energy storage device is configured to power on when receiving the power-on signal.
  • the energy storage device includes: a controller, a power conversion circuit and a battery pack; the first end of the power conversion circuit is connected to the battery pack, and the second end of the power conversion circuit is connected to the DC bus; After receiving the high voltage ride through information and the battery pack is in the discharging working state, the power conversion circuit is controlled to increase the output voltage reference value of the energy storage device to above the peak voltage of the high voltage ride through, so that the energy storage device continues to be in the discharging working state; After receiving the high voltage ride-through information and the battery pack is in the charging state, adjust the charging power reference value of the energy storage device to the charging power before the high voltage ride-through, so that the energy storage device continues to be in the charging state.
  • the inverter includes: a first optocoupler and a second optocoupler; a first input end of the first optocoupler is connected to an I/O port of the inverter, and the first optocoupler is connected to an I/O port of the inverter.
  • the first output terminal of the optical coupler is connected to the power supply, the second output terminal of the first optocoupler is connected to the first interface of the energy storage device; the first input terminal of the second optical coupler is connected to the I/O port of the inverter, and the second optical coupler is connected to the I/O port of the inverter.
  • the output end of the optocoupler is connected to the first interface of the energy storage drive circuit; the second input end of the first optocoupler and the second input end of the second optocoupler are both connected to the reference ground.
  • the embodiment of the present application further provides a high voltage ride through control method, which is applied to the optical storage system introduced in the above embodiment.
  • the advantages of the optical storage system provided by the above embodiment are the same It is applicable to the following method embodiments, and details are not repeated here.
  • the optical storage system includes an inverter and an energy storage device; the input end of the inverter is used to connect to the DC bus, the energy storage device is used to connect to the DC bus, and the output end of the inverter is used to connect to the AC grid; the method includes: receiving The high-voltage ride-through information sent by the inverter, the inverter is used to determine that the voltage of the AC grid has high-voltage ride-through; when receiving the high-voltage ride-through information, if the energy storage device is in the discharging state, the output voltage reference value is adjusted to maintain the discharge.
  • Working state if the energy storage device is in the charging working state, adjust the charging power reference value to maintain the charging working state.
  • the high voltage ride-through is performed according to its own working state, which specifically includes: receiving high-voltage ride-through information and the battery pack is in a discharging working state, and controlling the power conversion circuit to increase the output voltage reference value of the energy storage device to a high value above the peak voltage of the voltage ride-through, so that the energy storage device continues to be in the discharge working state; after receiving the high-voltage ride-through information and the battery pack is in the charging working state, adjust the charging power reference value of the energy storage device to the charging power before the high-voltage ride-through, So that the energy storage device continues to be in the charging working state.
  • the embodiments of the present application have the following advantages:
  • the inverter is used to identify whether the voltage of the AC power grid has high voltage ride-through. If high voltage ride-through occurs in the AC power grid, the inverter needs to notify the energy storage device that high voltage ride-through occurs, so that the energy storage device can take high voltage ride-through. Through measures, if the energy storage device is in the discharging working state, adjust the output voltage reference value to maintain the discharging working state; if the energy storage device is in the charging working state, adjust the charging power reference value to maintain the charging working state, so that the inverter can Control the grid-connected current to meet the standard requirements of the grid during high voltage ride-through.
  • the optical storage system includes both an inverter and an energy storage device.
  • the energy storage device is connected to the DC bus, and the voltage of the DC bus will be affected during high voltage ride-through. Therefore, when high voltage ride-through occurs in the AC power grid, it is necessary to notify the energy storage equipment in time. If the high voltage ride through is identified by the energy storage device, the general energy storage device determines whether the high voltage ride through occurs by identifying the voltage of the DC bus, but when the high voltage ride through occurs in the AC grid, the voltage rise of the DC bus is related to the DC bus capacitance.
  • the inverter can identify the high voltage ride-through and can more accurately determine the time of the high voltage ride-through.
  • FIG. 1 is a schematic diagram of an optical storage system according to an embodiment of the present application.
  • FIG. 2 is a schematic diagram of another optical storage system provided by an embodiment of the present application.
  • FIG. 3 is a schematic diagram of another optical storage system provided by an embodiment of the present application.
  • FIG. 4 is a schematic diagram of yet another optical storage system provided by an embodiment of the present application.
  • FIG. 5 is an internal architecture diagram of an energy storage device provided by an embodiment of the present application.
  • FIG. 6 is a schematic diagram of a connection between still another inverter and an energy storage device according to an embodiment of the present application
  • FIG. 7 is a schematic diagram of a control loop provided by an embodiment of the present application.
  • FIG. 8 is a schematic diagram of a power supply system provided by an embodiment of the present application.
  • FIG. 9 is a schematic diagram of another power supply system provided by an embodiment of the present application.
  • FIG. 10 is a flowchart of a control method for high voltage ride-through provided by an embodiment of the present application.
  • directional terms such as “upper” and “lower” may include, but are not limited to, definitions relative to the schematic placement of components in the drawings. It should be understood that these directional terms may be relative concepts, They are used for relative description and clarification, which may vary accordingly depending on the orientation in which the components are placed in the drawings.
  • connection should be understood in a broad sense.
  • connection may be a fixed connection, a detachable connection, or an integrated body; it may be directly connected, or Can be indirectly connected through an intermediary.
  • coupled may be a manner of electrical connection that enables signal transmission.
  • Coupling can be a direct electrical connection or an indirect electrical connection through an intermediate medium.
  • the embodiments of the present application relate to an optical storage system, which can perform both photovoltaic power generation and energy storage.
  • optical storage system which can perform both photovoltaic power generation and energy storage.
  • FIG. 1 this figure is a schematic diagram of an optical storage system provided by an embodiment of the present application.
  • the optical storage system provided in the embodiment of the present application includes: an inverter 100 and an energy storage device 200; and may also include a photovoltaic string PV.
  • the photovoltaic string PV is only schematically drawn, and an actual product generally includes a plurality of photovoltaic strings.
  • the input end of the inverter 100 is connected to the DC bus BUS, the output end of the inverter 100 is used to connect to the AC power grid; the DC bus BUS is used to connect the photovoltaic string PV; the DC bus BUS can be directly connected to the photovoltaic string PV, It is also possible to connect the PV string PV indirectly.
  • the optical storage system provided by the embodiment of the present application is shown in FIG. 2 , and may further include a DC/DC (Direct Current/Direct Current) converter 300, DC/DC
  • the input end of the DC converter 300 is used to connect the photovoltaic string PV, and the output end of the DC/DC converter 300 is connected to the DC bus BUS.
  • the embodiments of the present application do not limit the specific implementation of the DC/DC converter 300 , for example, it may be a boost circuit or a buck-boost circuit.
  • the DC/DC converter 300 may also be integrated in a DC combiner box.
  • the DC/DC converter 300 is used to convert the voltage output by the PV to DC and then send it to the DC bus BUS.
  • the energy storage device 200 is connected to the DC bus BUS.
  • the inverter 100 is used to send the high voltage ride through information to the energy storage device 200 when the voltage of the AC power grid has high voltage ride through.
  • the inverter 100 can send the high voltage ride-through information to the energy storage device 200 through a separate signal line, or can share other hardware signal lines, for example, can share the power-on signal line of the energy storage device 200, that is, after the inverter 100 is turned on , a power-on signal needs to be sent to the energy storage device 200 to enable the energy storage device 200 to be turned on.
  • the hardware interface of the inverter 100 can be saved, and the existing hardware interface of the inverter 100 can be used, and a new hardware interface does not need to be set up.
  • the power-on signal is used to inform the energy storage device 200 to power on and power off, such as hibernation and wake-up.
  • the inverter is used to identify whether the voltage of the AC power grid has a high voltage ride-through.
  • the inverter 100 can detect the voltage of the AC power grid in real time, and compare the detected voltage with a preset voltage threshold. When the detected voltage is greater than the preset voltage threshold, it means that high voltage ride-through occurs in the AC power grid. At this time, the inverter 100 needs to notify the energy storage device 200 that high voltage ride-through occurs, so that the energy storage device 200 can take high-voltage ride-through measures. In turn, the inverter can control the grid-connected power grid to meet the requirements of high voltage ride-through.
  • the optical storage system includes both the inverter and the energy storage device. Therefore, when a high voltage ride-through occurs in the AC grid, the energy storage device 200 needs to be notified in time. If the HVRT is identified by the energy storage device 200, the energy storage device 200 generally judges whether the HVRT occurs by identifying the voltage of the DC bus, but when the HVRT occurs in the AC grid, the voltage rise of the DC bus is different from the DC bus voltage. The size of the busbar capacitance is related, and the energy storage device 200 cannot accurately determine whether a high voltage ride-through occurs by the voltage rise of the DC busbar.
  • the energy storage device 200 is used to adjust the output voltage reference value to maintain the discharge working state if the energy storage device is in the discharge working state when receiving the high voltage ride through information, that is, continue to release energy to the DC bus; if the energy storage device is in the charging state In the working state, the charging power reference value is adjusted to maintain the charging working state, that is, continue to absorb energy from the DC bus.
  • the energy storage device 200 can take corresponding measures according to its own working state. For example, when the energy storage device 200 is in the discharging working state, the voltage of the DC bus can be rapidly increased to continue to maintain the discharging working state. It is avoided that the voltage of the DC bus is too high, and it is fed back to the energy storage device 200 to charge the battery pack in the energy storage device.
  • the purpose of raising the voltage of the DC bus by the energy storage device 200 is to keep the discharge working state of the energy storage device 200 unchanged, switch the working state between discharging and charging infrequently, and meet the requirements of high voltage ride-through, the inverter.
  • the output power can be requested according to the standard.
  • the energy storage device 200 can indirectly raise the voltage of the DC bus by raising the output voltage.
  • the energy storage device 200 if the energy storage device 200 is in the charging working state when the high voltage ride through occurs, it is necessary to adjust the charging power reference value of the energy storage device 200 to keep the energy storage device 200 in the charging working state. If the energy storage device 200 changes its working state when high voltage ride-through occurs in the AC power grid, it will affect the inverter 100 to control the grid-connected current, so that the high voltage ride through cannot be smoothly passed, and the normal operation of the energy storage device 200 and the inverter 100 will be affected. , in the worst case may cause damage to the hardware device.
  • the inverter identifies whether high voltage ride-through occurs in the AC power grid.
  • the inverter sends high voltage ride-through information to the energy storage device to notify the energy storage device.
  • a high voltage ride-through occurs, so that the energy storage device can adjust the output voltage reference value according to its own working state if the energy storage device is in the discharging working state to maintain the discharging working state, and adjust the charging power reference value if the energy storage device is in the charging working state. to maintain the charging state.
  • the energy storage device itself is not used to identify the high voltage ride-through, so that corresponding measures are taken.
  • the energy storage device cannot accurately determine whether high voltage ride through occurs, if the high voltage ride through occurs, the energy storage device does not judge in time, the high voltage will charge the energy storage device in the form of pulsating current, resulting in the inability of the inverter to accurately control
  • the grid-connected current cannot meet the grid-connected requirements of the AC grid.
  • FIG. 3 is a schematic diagram of a connection between an inverter and an energy storage device according to an embodiment of the present application.
  • the high-voltage ride-through information sent by the inverter 100 to the energy storage device 200 may be a level-encoded signal, for example, the high-voltage ride-through information is encoded into a pulse signal, and the pulse signal is sent to the energy storage device 200 .
  • the high voltage ride-through information can also be encoded into high and low level signals, and the high and low level signals are sent to the energy storage device 200, for example, a high level signal indicates that a high voltage ride through occurs.
  • the high voltage ride-through information is taken as an example of a pulse signal for introduction.
  • the inverter 100 is specifically configured to encode the high voltage ride-through information into a pulse signal, and send the pulse signal to the interface of the energy storage device 200 through its own I/O port.
  • the inverter 100 encodes the high voltage ride through information and sends it to the energy storage device 200.
  • the existing communication interface between the inverter 100 and the energy storage device 200 can be used, that is, the existing interface is reused; a communication interface can also be set up independently.
  • FIG. 4 is a schematic diagram of another connection between an inverter and an energy storage device according to an embodiment of the present application.
  • the interface through which the inverter 100 sends HVRT information can share the interface used in the inverter 100 for sending the power-on signal to the energy storage device 200, but the energy storage device 200 can use
  • the two different interfaces are connected to the same I/O port of the inverter 100 .
  • the inverter 100 is further configured to send a power-on signal to the second interface B of the energy storage device 200 through the I/O port.
  • the energy storage device 200 is configured to start up when a start-up signal is received.
  • the energy storage device 200 has different interfaces for receiving the power-on signal and receiving high voltage ride-through information, which are the first interface A and the second interface B, respectively. Therefore, the energy storage device 200 can determine the source from the interface and the signal type. Whether the signal of the inverter 100 is the power-on signal or the high voltage ride-through information.
  • the interface through which the energy storage device 200 receives the power-on signal and the high-voltage ride-through information may also be the same, as long as the signal types of the power-on signal and the high-voltage ride-through information are different, for example, the power-on signal Both the HVRT and HVRT information are square wave signals, but the frequencies of the corresponding square wave signals are different.
  • the power-on signal is a 100Hz square wave signal
  • the HVRT information is a 200Hz square wave signal
  • the power-on signal may be a pulse signal
  • the high voltage ride-through information may be a high-level signal.
  • the first interface A and the second interface B of the energy storage device 200 are both connected to the I/O port of the inverter 100, that is, the I/O port of the inverter 100 is used to send both a power-on signal and a high voltage ride through. information.
  • the signal formats of the power-on signal and the high-voltage ride-through information are different. Therefore, the first interface A and the second interface B of the energy storage device 200 can identify the received signals respectively, so as to determine whether the power-on signal or the high voltage ride-through signal is received.
  • Voltage ride through information When the received signal is high-voltage ride-through information, high-voltage ride-through measures are taken according to whether it is in a charging working state or a discharging working state.
  • the energy storage device uses two different interfaces to connect to the same I/O port of the inverter. It should be understood that the energy storage device can also use only one interface to connect to the I/O port of the inverter. The device distinguishes whether it is a high voltage ride-through signal or a power-on signal by identifying the format of the signal sent by the inverter.
  • this figure is an internal structure diagram of an energy storage device provided by an embodiment of the present application.
  • the energy storage device provided in this embodiment of the present application includes: a controller 201 , a power conversion circuit 202 , and a battery pack 203 .
  • the first end of the power conversion circuit 202 is connected to the battery pack 203, and the second end of the power conversion circuit 202 is connected to the DC bus BUS, that is, when the energy storage device is discharging, the output voltage of the power conversion circuit 202 is the voltage of the DC bus.
  • the output end of the conversion circuit 202 is connected to the DC bus, that is, the output voltage of the power conversion circuit 202 is consistent with the voltage of the DC bus.
  • the controller 201 is used to receive the high voltage ride-through information and the battery pack 203 is in a discharging working state, and control the power conversion circuit 202 to increase the output voltage reference value of the energy storage device to a peak voltage of the high voltage ride-through, so that the energy storage device 200 Continue to be in the discharge working state; also used to receive the high voltage ride through information and the battery pack 203 is in the charging working state, adjust the charging power reference value of the energy storage device to the charging power before the high voltage ride through, so that the energy storage device 200 Continue to maintain the charging working state.
  • the power conversion circuit 202 in the embodiment of the present application may be a bidirectional DC/DC circuit, that is, it satisfies two states of charging and discharging of the battery pack 203 .
  • the power conversion circuit 202 may be a booster circuit or a booster/bucker circuit, which is not specifically limited in this embodiment of the present application.
  • the controller 201 receives the high voltage ride-through information sent by the inverter 100, the controller 201 controls the power conversion circuit 202 to increase the output voltage, and the power conversion circuit 202 increases the voltage of the battery pack 203 and outputs it to the DC bus BUS.
  • the voltage of the DC bus can be increased to be higher than the standard high voltage ride through peak voltage, for example, 1.4 times higher than the rated voltage peak value.
  • a possible implementation manner is to control the output voltage of the power conversion circuit to a preset multiple of the rated voltage of the AC power grid, and the value interval of the preset multiple is greater than 1.4 and less than 2, wherein the preset multiple can be specifically based on the standard of the power grid.
  • the rated voltage refers to the rated voltage of the AC grid. It should be understood that the corresponding standards may be different in different power grid environments. When high voltage ride-through occurs, the voltage of the DC bus needs to be raised above the peak voltage of the high voltage ride-through required by the standard.
  • the energy storage device 200 When the energy storage device 200 is in the charging working state and high voltage ride-through occurs in the AC grid, the energy storage device 200 needs to adjust the charging power reference value of the energy storage device to the charging power before the high voltage ride-through, that is, to ensure charging The power is the same as before the high voltage ride through.
  • the inverter charges the battery pack 203 in the energy storage device 200, but the charging power that the inverter can provide may be greater than the power required by the energy storage device 200, or the inverter may The provided charging power is less than the power required by the energy storage device 200 .
  • the inverter When the charging power that the inverter can provide is greater than the power required by the energy storage device 200, the inverter can meet the charging requirement of the energy storage device 200. At this time, the voltage control loop of the energy storage device 200 fails, and the power control loop to control charging.
  • the voltage of the energy storage device 200 will not rise, and all the charging power provided by the inverter is absorbed by the energy storage device 200. At this time, the energy storage device The voltage control loop of 200 works, and the voltage control loop of the energy storage device 200 can control the voltage of the DC bus BUS.
  • FIG. 6 is a schematic diagram of a connection between yet another inverter and an energy storage device according to an embodiment of the present application.
  • the inverter includes: a first optical coupler U1 and a second optical coupler U2;
  • the first input end of the first optocoupler U1 is connected to the I/O port of the inverter 100, and the second output end of the first optocoupler U1 is connected to the first interface A of the controller 201;
  • the first output terminal is connected to the power supply VCC through the third resistor R3, for example, the VCC is 3.3V.
  • the first input end of the second optocoupler U2 is connected to the I/O port of the inverter 100 , and the first output end of the second optocoupler U2 is connected to the first interface B of the energy storage driving circuit 300 .
  • the second output end of the second optocoupler U2 is connected to the second interface C of the energy storage driving circuit 300 .
  • the energy storage driving circuit 300 drives the energy storage device to start up when receiving the power-on signal.
  • the second input terminal of the first optical coupler U1 and the second input terminal of the second optical coupler U2 are both connected to the reference potential ground GND. It should be understood that the grounds corresponding to the input end and the output end of the two optocouplers are different grounds, so as to achieve electrical isolation and avoid interference of the signal at the input end of the optocoupler with the signal at the output end.
  • the energy storage system provided in this embodiment further includes a first resistor R1, a second resistor R2 and a third resistor R3.
  • the first input end of the first optocoupler U1 is connected to the I/O port of the inverter 100 through the first resistor R1.
  • the first input end of the second optocoupler U2 is connected to the inverter through the second resistor R2.
  • the I/O ports of the inverter 100 that is, the first input end of the first optocoupler U1 and the first input end of the second optocoupler U2 are both connected to the I/O ports of the inverter 100 . But the outputs of the two optocouplers are connected to different inputs of the energy storage device.
  • the two optocouplers and the peripheral resistors and diodes described above can be integrated with the inverter 100, that is, integrated in the cabinet of the inverter 100, while the controller 201 and the energy storage drive
  • the circuit 300 is located on one side of the energy storage device, for example, inside an energy storage container.
  • the first optocoupler U1 When the I/O port of the inverter 100 outputs a high level, and the first input terminal of the first optocoupler U1 is at a high level, the first optocoupler U1 is turned on, that is, the first optocoupler U1 is turned on.
  • An output terminal is connected to the second output terminal, that is, the first interface A of the controller 201 is connected to VCC, that is, the first interface A receives a high-level signal.
  • the first output end of the second optocoupler U2 is connected to the first interface B of the energy storage drive circuit 300, and the second output end of the second optocoupler U2 is connected to the second interface C of the energy storage drive circuit 300. Therefore, When the I/O port of the inverter 100 outputs a high level, the second optocoupler U2 is turned on, and at this time, the first output end and the second output end of the second optocoupler U2 are connected.
  • the controller 201 and the interface B of the energy storage drive circuit 300 can identify the signal sent by the inverter 100 Whether it is a power-on signal or a high voltage ride-through information.
  • FIG. 7 is a schematic diagram of a control loop for charging and discharging an energy storage device provided in an embodiment of the present application.
  • the inverter can control the charging and discharging of the energy storage device. During actual operation, the inverter can send the output voltage reference value Vref, the charging power reference value P1ref and the discharge power reference value P2ref to the energy storage device through the communication line.
  • the energy storage device can It controls its own charging and discharging according to the output voltage reference value Vref, the charging power reference value P1ref and the discharging power reference value P2ref.
  • the energy storage device When Vref ⁇ DC bus voltage Vbus, the energy storage device absorbs energy from the DC bus to charge the battery pack.
  • the charging principle is that the actual charging power P1 of the energy storage device is less than or equal to the charging power reference value P1ref; that is, when charging, theoretically P1 does not greater than P1ref.
  • the battery pack in the energy storage device is discharged from the DC bus.
  • the discharge principle is that the discharge power P2 is less than or equal to the discharge power reference value P2ref, that is, the discharge power P2 is not greater than the discharge power reference value P2ref.
  • the energy storage device can continue to maintain the discharge working state only if the bus voltage is increased, otherwise the inverter Excessive energy will flow back into the battery pack, and the battery pack cannot continue to maintain the discharge working state.
  • the inverter cannot control its own output current, and thus cannot make its own output current meet the standard requirements during high voltage ride-through, that is, it cannot control the grid-connected current to meet the high voltage ride-through. standard requirements.
  • the energy storage device can increase the voltage of the DC bus by increasing the output voltage reference value, for example, setting the output voltage reference value to be higher than the peak voltage of the high voltage ride through required by the grid standard.
  • the energy storage device should adjust the charging power reference value to the charging power during high voltage ride-through, that is, set the actual charging power before the high voltage ride-through as the charging power. Power reference value.
  • the purpose is to make the bus voltage control loop of the energy storage device fail, and the inverter controls the voltage of the DC bus.
  • the above embodiment describes an optical storage system, which is applied to the field of photovoltaic power generation.
  • the embodiment of the present application also provides a power supply system, which does not limit the specific application field. As long as there are inverters and energy storage devices, it does not It appears that the source of the power supply at the input end of the inverter can be, for example, wind power generation or water conservancy power generation.
  • FIG. 8 this figure is a schematic diagram of a power supply system provided by an embodiment of the present application.
  • the power supply system provided by the embodiment of the present application includes: an inverter 100 and an energy storage device 200;
  • the input end of the inverter 100 is connected to the DC bus BUS, and the output end of the inverter 100 is used to connect to the AC power grid;
  • the energy storage device 200 is connected to the DC bus BUS.
  • the DC bus BUS is also used to connect the DC power supply 400 .
  • the embodiment of the present application does not limit the type of the DC power source 400 .
  • the above embodiments are described by taking the DC power source as an example of a photovoltaic string.
  • the DC power source 400 may be other types of DC power sources other than the photovoltaic string. .
  • the inverter 100 is used for sending high voltage ride through information to the energy storage device 200 when the voltage of the AC power grid occurs high voltage ride through;
  • the energy storage device 200 is configured to adjust the output voltage reference value to maintain the discharge working state if the energy storage device 200 is in the discharging working state when receiving the high voltage ride through information, and adjust the charging power if the energy storage device 200 is in the charging working state Reference value to maintain the charging working state.
  • the power supply system may further include a DC/DC converter 300, as shown in FIG. Connect the DC bus BUS.
  • the inverter can encode the high voltage ride through information into a pulse signal, and send the pulse signal to the first interface of the energy storage device through its own I/O port.
  • the pulse signal here may be a square wave signal or a level signal, which is not specifically limited here.
  • the inverter can reuse the existing interface to send the HVRT information, for example, the interface that sends the power-on signal to the energy storage device is multiplexed.
  • the energy storage device can use two different interfaces to identify the HVRT information and the power-on signal. For example, the inverter sends a power-on signal to the second interface of the energy storage device through the I/O port.
  • the energy storage device 200 is further configured to start up when a start-up signal is received. Generally, the inverter 100 is turned on first, and then the inverter 100 controls the energy storage device 200 to turn on.
  • the energy storage device may generally include: a controller, a power conversion circuit, and a battery pack.
  • the battery pack may include multiple battery clusters, and each battery cluster includes multiple battery modules.
  • multiple battery clusters are placed in an energy storage container, and multiple battery clusters are connected to the DC bus through a power conversion circuit.
  • the first end of the power conversion circuit is connected to the battery pack, and the second end of the power conversion circuit is connected to the DC bus.
  • the controller is used to receive the high voltage ride through information and the battery pack is in the discharge state, and control the power conversion circuit to increase the output voltage reference value of the energy storage device to above the peak voltage of the high voltage ride through, so that the energy storage device continues to be in discharge work It is also used to receive the HVRT information and the battery pack is in the charging working state, adjust the charging power reference value of the energy storage device to the charging power before the HVRT, so that the energy storage device continues to be in the charging working state.
  • the inverter is used to identify whether the voltage of the AC power grid has high voltage ride-through. If high voltage ride-through occurs in the AC power grid, the inverter needs to notify the energy storage device that high voltage ride-through occurs, so that the energy storage device can take high voltage ride-through. Ride through measures, so that the inverter can control the grid-connected power grid to meet the requirements of high voltage ride through. Since there is no energy storage device in the traditional AC power grid, when high voltage ride-through occurs in the AC power grid, it is not necessary to consider the working condition of the energy storage device.
  • the optical storage system includes both inverters and energy storage devices. Therefore, when high voltage ride-through occurs in the AC grid, the energy storage devices need to be notified in time.
  • the general energy storage device determines whether the high voltage ride through occurs by identifying the voltage of the DC bus. It is related to the size of the energy storage device, and the energy storage device cannot accurately judge whether a high voltage ride through occurs through the voltage rise of the DC bus.
  • the inverter can identify the high voltage ride-through and can more accurately determine the time of the high voltage ride-through.
  • the energy storage device can continue to maintain the discharge working state only if the bus voltage is increased, otherwise the inverter Excessive energy will flow back into the battery pack, and the battery pack cannot continue to maintain the discharge working state. If the voltage of the DC bus does not increase, the inverter cannot control its own output current, and thus cannot make its own output current meet the standard requirements during high voltage ride-through, that is, it cannot control the grid-connected current to meet the high voltage ride-through standard. Require. Specifically, the energy storage device can increase the voltage of the DC bus by increasing the output voltage reference value.
  • the energy storage device should adjust the charging power reference value to the charging power during HVRT, that is, set the actual charging power during HVRT as the charging power reference value .
  • the purpose is to make the bus voltage control loop of the energy storage device fail, and the inverter controls the voltage of the DC bus.
  • the power-on signal and the high voltage ride-through information sent by the inverter to the energy storage device can be multiplexed on the same I/O port.
  • the inverter includes a first optocoupler and a second optocoupler; the input end of the first optocoupler is connected to the I/O port of the inverter, and the output end of the first optocoupler is connected to The first interface of the energy storage device; the input end of the second optocoupler is connected to the I/O port of the inverter, and the output end of the second optocoupler is connected to the second interface of the energy storage device.
  • the specific working principle can be seen in the above figure The description of Part 6 will not be repeated here.
  • the embodiments of the present application further provide a high voltage ride-through control method, which will be described in detail below with reference to the accompanying drawings.
  • FIG. 10 is a flowchart of a control method for high voltage ride-through provided by an embodiment of the present application.
  • the high-voltage ride-through control method provided in this embodiment is applied to an optical storage system.
  • the optical storage system includes an inverter and an energy storage device; the input end of the inverter is used for connecting the DC bus, and the energy storage device is used for connecting the DC bus , the output of the inverter is used to connect to the AC grid;
  • the method includes:
  • S1001 Receive the high voltage ride-through information sent by the inverter.
  • the inverter is used to judge whether the high voltage ride through occurs through the voltage of the AC power grid. That is, it informs the energy storage device that a high voltage ride-through has occurred.
  • the energy storage device When the energy storage device performs high voltage ride through, it can take corresponding measures according to its own working state, which can be divided into the following two situations.
  • the first type the energy storage device is in discharge working state
  • the energy storage device can continue to maintain the discharge working state only if the bus voltage is increased, otherwise the inverter Excessive energy will flow back into the battery pack, and the battery pack cannot continue to maintain the discharge working state. If the voltage of the DC bus does not increase, the inverter cannot control its own output current, and thus cannot make its own output current meet the standard requirements during high voltage ride-through, that is, it cannot control the grid-connected current to meet the high voltage ride-through standard. Require. Specifically, the energy storage device can increase the voltage of the DC bus by increasing the output voltage reference value.
  • the second type the energy storage device is in charging working state
  • the energy storage device can take corresponding measures according to its own working state. For example, when the energy storage device is in the discharging working state, the voltage of the DC bus can be rapidly increased to continue to maintain the discharging working state and avoid DC The voltage of the busbar is too high, and it is fed back to the energy storage device to charge the battery pack in the energy storage device.
  • the purpose of the energy storage device to raise the voltage of the DC bus is to keep the energy storage device in the discharge working state, and not frequently switch the working state between discharge and charging, and when the high voltage ride-through is satisfied, the inverter can follow the Standard requires output power. Specifically, the energy storage device can indirectly raise the voltage of the DC bus by raising the output voltage.
  • the energy storage device is in the charging working state when high voltage ride through occurs, it is necessary to adjust the charging power reference value of the energy storage device so that the energy storage device continues to maintain the charging working state. If the energy storage device changes its working state when the AC power grid has high voltage ride-through, it will affect the inverter's control of the grid-connected current, so that the high voltage ride-through cannot be smoothly passed, affecting the normal operation of the energy storage device and the inverter. May cause damage to hardware devices.
  • the inverter identifies whether high voltage ride-through occurs in the AC power grid.
  • the inverter sends high voltage ride-through information to the energy storage device to notify the energy storage device.
  • a high voltage ride-through occurs, so that the energy storage device can adjust the output voltage reference value according to its own working state if the energy storage device is in the discharging working state to maintain the discharging working state, and adjust the charging power reference value if the energy storage device is in the charging working state. to maintain the charging state.
  • the energy storage device itself is not used to identify the high voltage ride-through, so that corresponding measures are taken.
  • the energy storage device cannot accurately determine whether high voltage ride through occurs, if the high voltage ride through occurs, the energy storage device does not judge in time, the high voltage will charge the energy storage device in the form of pulsating current, resulting in the inability of the inverter to accurately control
  • the grid-connected current cannot meet the grid-connected requirements of the AC grid.
  • At least one (item) refers to one or more, and "a plurality” refers to two or more.
  • “And/or” is used to describe the relationship between related objects, indicating that there can be three kinds of relationships, for example, “A and/or B” can mean: only A, only B, and both A and B exist , where A and B can be singular or plural.
  • the character “/” generally indicates that the associated objects are an “or” relationship.
  • At least one item(s) below” or similar expressions thereof refer to any combination of these items, including any combination of single item(s) or plural items(s).
  • At least one (a) of a, b or c can mean: a, b, c, "a and b", “a and c", “b and c", or "a and b and c" ", where a, b, c can be single or multiple.

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Abstract

本申请公开了一种光储系统、电源及高电压穿越控制方法，包括：逆变器和储能设备；逆变器的输入端连接直流母线，逆变器的输出端连接交流电网；直流母线用于连接光伏组串；储能设备连接直流母线；逆变器用于交流电网的电压发生高电压穿越时，向储能设备发送高电压穿越信息；储能设备用于在收到高电压穿越信息时，储能设备处于放电工作状态则调整输出电压参考值维持放电工作状态，储能设备处于充电工作状态则调整充电功率参考值维持充电工作状态。交流电网发生高电压穿越时，直流母线的电压的上升情况与直流母线电容的大小相关，储能设备不能准确通过直流母线的电压上升判断是否发生高电压穿越，由逆变器来识别高电压穿越可以准确判定高电压穿越。

Description

一种光储系统、电源系统及高电压穿越控制方法 技术领域
本申请涉及光伏发电技术领域，尤其涉及一种光储系统、电源系统及高电压穿越控制方法。
背景技术
目前，光伏发电、风力发电以及水利发电越来越被重视，例如光伏发电是将太阳能转换为电能，在光伏发电中目前将发电和储能结合在一起使用，即形成光储系统。
光储系统一般包括光伏阵列、直流/直流(DC/DC，Direct Current/Direct Current)变换器、逆变器(DC/AC，Direct Current/alternating Current)和储能设备；其中DC/DC变换器的输出端连接直流母线，逆变器的输入端连接直流母线，储能设备连接直流母线。逆变器的输出端连接交流电网。
实际运行时，交流电网容易发生高电压穿越，由于逆变器的输入端连接直流母线，直流母线上又连接储能设备，因此，逆变器输出端的高电压将会影响直流母线电压，因此，如何在光储系统发生高电压穿越时控制储能设备的工作状态是本领域技术人员需要解决的技术问题。
发明内容
本申请提供了一种光储系统、电源系统及控制方法，能够在交流电网发生高电压穿越时，控制储能设备正常工作。
本申请实施例提供一种光储系统，应用于光伏发电并且带有储能设备的场景，即包括逆变器和储能设备；逆变器的输入端用于连接直流母线，逆变器的输出端用于连接交流电网；直流母线连接光伏组串，光伏组串为直流母线提供直流电；储能设备用于连接直流母线，储能设备既能从直流母线吸收能量为自身充电，又可以向直流母线释放能量实现放电；逆变器在交流电网的电压发生高电压穿越时，向储能设备发送高电压穿越信息；储能设备在收到高电压穿越信息时，根据自身工作状态采取措施，具体为：如果储能设备处于放电工作状态则调整输出电压参考值以维持放电工作状态，如果储能设备处于充电工作状态则调整充电功率参考值以维持充电工作状态。
本申请实施例提供的光储系统，利用逆变器来识别交流电网的电压是否发生高电压穿越，逆变器识别交流电网发生高电压穿越时，通知储能设备以便储能设备采取对应的措施，如果储能设备处于放电工作状态则调整输出电压参考值以维持放电工作状态，以免直流母线上波动的高电压向储能设备反灌能量。如果储能设备处于充电工作状态则调整充电功率参考值以维持充电工作状态，进而使逆变器可以控制并网电流，以满足高电压穿越时电网的标准要求。本申请实施例提供的光储系统，在交流电网发生高电压穿越时，控制储能设备维持原工作状态不变，避免其因为高电压穿越频繁切换工作状态，对设备产生损坏。如果由储能设备来识别高电压穿越，一般储能设备通过识别直流母线的电压来判断是否发生了高电压穿越，但是交流电网发生高电压穿越时，直流母线的电压的上升情况与直流母线电容的大小相关，储能设备不能准确通过直流母线的电压上升情况判断是否发生了高电压穿越。本申请实施例由逆变器来识别高电压穿越可以更加准确判定高电压穿越的时刻。
在一种可能的实现方式中，储能设备包括：控制器、功率变换电路和电池包；功率变换电路的第一端连接电池包，功率变换电路的第二端连接直流母线；该功率变换电路为
控制器用于收到高电压穿越信息且电池包处于放电工作状态，储能设备向直流母线输出能量，控制功率变换电路升高储能设备的输出电压参考值至高电压穿越的峰值电压以上，以使储能设备继续处于放电工作状态；可以快速升高直流母线的电压，以便继续保持放电工作状态，避免直流母线的电压太高，反灌到储能设备给储能设备中的电池包充电。储能设备抬高直流母线的电压的目的是为了使储能设备保持放电工作状态不变，不频繁在放电和充电之间进行工作状态的切换，而且满足高电压穿越时，逆变器可以按照标准要求输出功率。控制器还用于收到高电压穿越信息且电池包处于充电工作状态，调整储能设备的充电功率参考值为高电压穿越前的充电功率，以使储能设备继续处于充电工作状态。如果交流电网发生高电压穿越时，储能设备改变工作状态，则影响逆变器控制并网电流，进而不能平稳度过高电压穿越，影响储能设备和逆变器的正常运行，最坏时可能对硬件设备造成损坏。
在一种可能的实现方式中，逆变器，具体用于将高电压穿越信息编码为脉冲信号，将脉冲信号通过自身的I/O口发送给储能设备的第一接口。逆变器向储能设备发送高电压穿越信息可以为电平编码信号，例如将高电压穿越信息编码为脉冲信号，将脉冲信号发送给储能设备。另外，还可以将高电压穿越信息编码为高低电平信号，将高低电平信号发送给储能设备，例如高电平信号表示发生了高电压穿越。
在一种可能的实现方式中，为了节省逆变器的硬件I/O口，本申请实施例中将逆变器发送高电压穿越信息的接口与发送开机信号的接口共用同一个接口，该光储系统还包括：储能驱动电路；逆变器，还用于通过I/O口将开机信号发送给储能驱动电路的第一接口；储能驱动电路，用于在收到开机信号时驱动储能设备进行开机。
在一种可能的实现方式中，为了更好地隔离逆变器和储能设备直接的信号干扰，本实施例提供的逆变器包括：第一光耦合器和第二光耦合器；第一光耦合器的第一输入端连接逆变器的I/O口，第一光耦合器的第一输出端连接电源，第一光耦合器的第二输出端连接储能设备的第一接口；第二光耦合器的第一输入端连接逆变器的I/O口，第二光耦合器的输出端连接储能驱动电路的第一接口；第一光耦合器的第二输入端和第二光耦合器的第二输入端均连接参考地。
在一种可能的实现方式中，还包括：直流/直流变换器；直流/直流变换器的输入端用于连接光伏组串；直流/直流变换器的输出端用于连接直流母线。直流/直流变换器可以将光伏组串的输出电压转换为直流母线匹配的电压，本申请实施例不限定直流/直流变换器的具体实现形式，可以为升压电路，也可以为升降压电路。另外，本申请实施例不具体限定光伏组串的数量，一般直流/直流变换器的输入端连接多个光伏组串。本申请实施例也不具体限定直流母线连接的直流/直流变换器的数量，可以为多个。
在一种可能的实现方式中，控制器，具体用于控制功率变换电路的输出电压参考值至交流电网的额定电压的预设倍数，预设倍数的取值区间为大于1.4小于2。
基于以上实施例提供的一种光储系统，以上的光储系统各个实施例对应的优点同样适 用于以下的电源系统，在此不再赘述。本申请实施例还提供一种电源系统，包括：逆变器和储能设备；逆变器的输入端连接直流母线，逆变器的输出端用于连接交流电网；储能设备连接直流母线；逆变器，用于交流电网的电压发生高电压穿越时，向储能设备发送高电压穿越信息；储能设备，用于在收到高电压穿越信息时，如果储能设备处于放电工作状态则调整输出电压参考值以维持放电工作状态，如果储能设备处于充电工作状态则调整充电功率参考值以维持充电工作状态。
在一种可能的实现方式中，逆变器，具体用于将高电压穿越信息编码为脉冲信号，将脉冲信号通过自身的I/O口发送给储能设备的第一接口。
在一种可能的实现方式中，逆变器，还用于通过I/O口将开机信号发送给储能设备的第二接口；储能设备，用于在收到开机信号时进行开机。
在一种可能的实现方式中，储能设备包括：控制器、功率变换电路和电池包；功率变换电路的第一端连接电池包，功率变换电路的第二端连接直流母线；控制器，用于收到高电压穿越信息且电池包处于放电工作状态，控制功率变换电路升高储能设备的输出电压参考值至高电压穿越的峰值电压以上，以使储能设备继续处于放电工作状态；还用于收到高电压穿越信息且电池包处于充电工作状态，调整储能设备的充电功率参考值为高电压穿越前的充电功率，以使储能设备继续处于充电工作状态。
在一种可能的实现方式中，逆变器包括：第一光耦合器和第二光耦合器；第一光耦合器的第一输入端连接逆变器的I/O口，第一光耦合器的第一输出端连接电源，第一光耦合器的第二输出端连接储能设备的第一接口；第二光耦合器的第一输入端连接逆变器的I/O口，第二光耦合器的输出端连接储能驱动电路的第一接口；第一光耦合器的第二输入端和第二光耦合器的第二输入端均连接参考地。
基于以上实施例提供的一种光储系统，本申请实施例还提供一种高电压穿越的控制方法，应用于以上实施例介绍的光储系统，以上实施例提供的光储系统的各个优点同样适用于以下的方法实施例，在此不再赘述。光储系统包括逆变器和储能设备；逆变器的输入端用于连接直流母线，储能设备用于连接直流母线，逆变器的输出端用于连接交流电网；该方法包括：接收逆变器发送的高电压穿越信息，逆变器用于判断交流电网的电压发生高电压穿越；在收到高电压穿越信息时，如果储能设备处于放电工作状态则调整输出电压参考值以维持放电工作状态，如果储能设备处于充电工作状态则调整充电功率参考值以维持充电工作状态。
在一种可能的实现方式中，根据自身工作状态进行高电压穿越，具体包括：收到高电压穿越信息且电池包处于放电工作状态，控制功率变换电路升高储能设备的输出电压参考值至高电压穿越的峰值电压以上，以使储能设备继续处于放电工作状态；收到高电压穿越信息且电池包处于充电工作状态，调整储能设备的充电功率参考值为高电压穿越前的充电功率，以使储能设备继续处于所述充电工作状态。
从以上技术方案可以看出，本申请实施例具有以下优点：
本申请实施例中利用逆变器来识别交流电网的电压是否发生高电压穿越，交流电网发生高电压穿越，逆变器需要通知储能设备发生了高电压穿越，以便于储能设备采取高电压 穿越的措施，如果储能设备处于放电工作状态则调整输出电压参考值以维持放电工作状态，如果储能设备处于充电工作状态则调整充电功率参考值以维持充电工作状态，进而使逆变器可以控制并网电流，以满足高电压穿越时电网的标准要求。由于传统的交流电网中不存在储能设备，因此，在交流电网出现高电压穿越时，不需要考虑储能设备的工作情况。而光储系统中既包括逆变器，又包括储能设备，储能设备连接直流母线，高电压穿越时会影响直流母线的电压。因此，交流电网发生高电压穿越时，需要及时通知储能设备。如果由储能设备来识别高电压穿越，一般储能设备通过识别直流母线的电压来判断是否发生了高电压穿越，但是交流电网发生高电压穿越时，直流母线的电压的上升情况与直流母线电容的大小相关，储能设备不能准确通过直流母线的电压上升情况判断是否发生了高电压穿越。本申请实施例由逆变器来识别高电压穿越可以更加准确判定高电压穿越的时刻。
附图说明
图1为本申请实施例提供的一种光储系统的示意图；
图2为本申请实施例提供的另一种光储系统的示意图；
图3为本申请实施例提供的又一种光储系统的示意图；
图4为本申请实施例提供的再一种光储系统的示意图；
图5为本申请实施例提供的一种储能设备的内部架构图；
图6为本申请实施例提供的再一种逆变器与储能设备的连接示意图；
图7为本申请实施例提供的一种控制环路示意图；
图8为本申请实施例提供的一种电源系统的示意图；
图9为本申请实施例提供的另一种电源系统的示意图；
图10为本申请实施例提供的一种高电压穿越的控制方法流程图。
具体实施方式
以下说明中的“第一”、“第二”等用词仅用于描述目的，而不能理解为指示或暗示相对重要性或者隐含指明所指示的技术特征的数量。由此，限定有“第一”、“第二”等的特征可以明示或者隐含地包括一个或者更多该特征。在本申请的描述中，除非另有说明，“多个”的含义是两个或两个以上。
此外，本申请中，“上”、“下”等方位术语可以包括但不限于相对附图中的部件示意置放的方位来定义的，应当理解到，这些方向性术语可以是相对的概念，它们用于相对于的描述和澄清，其可以根据附图中部件附图所放置的方位的变化而相应地发生变化。
在本申请中，除非另有明确的规定和限定，术语“连接”应做广义理解，例如，“连接”可以是固定连接，也可以是可拆卸连接，或成一体；可以是直接相连，也可以通过中间媒介间接相连。此外，术语“耦接”可以是实现信号传输的电性连接的方式。“耦接”可以是直接的电性连接，也可以通过中间媒介间接电性连接。
本申请实施例涉及一种光储系统，既可以进行光伏发电，又可以进行储能。为了使本领域技术人员更好地理解本申请实施例提供的光储系统，下面结合附图进行介绍。
光储系统实施例
参见图1，该图为本申请实施例提供的一种光储系统的示意图。
本申请实施例提供的光储系统包括：逆变器100和储能设备200；还可以包括光伏组串PV。图1中仅是示意性画了光伏组串PV，实际产品中，一般包括多个光伏组串。
其中，逆变器100的输入端连接直流母线BUS，逆变器100的输出端用于连接交流电网；直流母线BUS用于连接光伏组串PV；其中直流母线BUS可以直接连接光伏组串PV，也可以间接连接光伏组串PV。
当直流母线BUS间接连接光伏组串PV时，本申请实施例提供的光储系统如图2所示，还可以包括直流/直流(DC/DC，Direct Current/Direct Current)变换器300，DC/DC变换器300的输入端用于连接光伏组串PV，DC/DC变换器300的输出端连接直流母线BUS。本申请实施例不限定DC/DC变换器300的具体实现方式，例如可以为升压电路，也可以为升降压电路，另外，DC/DC变换器300还可以集成在直流汇流箱中。DC/DC变换器300用于将PV输出的电压进行直流变换后输送给直流母线BUS。
储能设备200连接直流母线BUS。
逆变器100，用于交流电网的电压发生高电压穿越时，向储能设备200发送高电压穿越信息。
逆变器100可以通过单独的信号线将高电压穿越信息发送给储能设备200，也可以共用其他的硬件信号线，例如可以共用储能设备200的开机信号线，即逆变器100开机后，需要向储能设备200发送开机信号，以使储能设备200开机。当高电压穿越信息共用开机信号线时，可以节省逆变器100的硬件接口，使用逆变器100现有的硬件接口即可，不必另外设置新的硬件接口。开机信号是为了告知储能设备200进行开机和关机，例如休眠和唤醒。
本申请实施例中利用逆变器来识别交流电网的电压是否发生高电压穿越，例如具体实现时，逆变器100可以实时检测交流电网的电压，将检测的电压与预设电压阈值进行比较，当检测的电压大于预设电压阈值时，说明交流电网发生高电压穿越，此时逆变器100需要通知储能设备200发生了高电压穿越，以便于储能设备200采取高电压穿越的措施，进而使逆变器可以控制并网电网满足高电压穿越的要求。
由于传统的交流电网中不存在储能设备，因此，在交流电网出现高电压穿越时，不需要考虑储能设备的工作情况。而光储系统中既包括逆变器，又包括储能设备，因此，交流电网发生高电压穿越时，需要及时通知储能设备200。如果由储能设备200来识别高电压穿越，一般储能设备200通过识别直流母线的电压来判断是否发生了高电压穿越，但是交流电网发生高电压穿越时，直流母线的电压的上升情况与直流母线电容的大小相关，储能设备200不能准确通过直流母线的电压上升情况判断是否发生了高电压穿越。
储能设备200，用于在收到高电压穿越信息时，如果储能设备处于放电工作状态则调整输出电压参考值以维持放电工作状态，即继续向直流母线释放能量；如果储能设备处于充电工作状态则调整充电功率参考值以维持充电工作状态，即继续从直流母线吸收能量。
当发生高电压穿越时，储能设备200可以根据自身的工作状态采取对应的措施，例如当储能设备200处于放电工作状态时，可以快速升高直流母线的电压，以便继续保持放电工作状态，避免直流母线的电压太高，反灌到储能设备200给储能设备中的电池包充电。 储能设备200抬高直流母线的电压的目的是为了使储能设备200保持放电工作状态不变，不频繁在放电和充电之间进行工作状态的切换，而且满足高电压穿越时，逆变器可以按照标准要求输出功率。具体地，储能设备200可以通过抬高输出电压来间接抬高直流母线的电压。另外，如果发生高电压穿越时，储能设备200处于充电工作状态，则需要调整储能设备200的充电功率参考值，以使储能设备200继续维持充电工作状态。如果交流电网发生高电压穿越时，储能设备200改变工作状态，则影响逆变器100控制并网电流，进而不能平稳度过高电压穿越，影响储能设备200和逆变器100的正常运行，最坏时可能对硬件设备造成损坏。
本申请实施例提供的光储系统，由逆变器来识别交流电网是否发生高电压穿越，当交流电网发生高电压穿越时，逆变器向储能设备发送高电压穿越信息，告知储能设备发生了高电压穿越，以便于储能设备根据自身工作状态，如果储能设备处于放电工作状态则调整输出电压参考值以维持放电工作状态，如果储能设备处于充电工作状态则调整充电功率参考值以维持充电工作状态。本申请实施例中并不是由储能设备自身来识别高电压穿越，从而采取对应的措施。因为储能设备并不能准确判断是否发生高电压穿越，如果发生高电压穿越时，储能设备没有及时判断出来会使高电压以脉动电流的方式为储能设备充电，导致逆变器无法精确控制并网电流，无法满足交流电网的并网要求。
下面结合附图详细介绍本申请实施例提供的光储系统中，逆变器为储能设备发送高电压穿越信息的具体实现方式。
参见图3，该图为本申请实施例提供的一种逆变器与储能设备的连接示意图。
逆变器100向储能设备200发送高电压穿越信息可以为电平编码信号，例如将高电压穿越信息编码为脉冲信号，将脉冲信号发送给储能设备200。另外，还可以将高电压穿越信息编码为高低电平信号，将高低电平信号发送给储能设备200，例如高电平信号表示发生了高电压穿越。本实施例中以高电压穿越信息为脉冲信号为例进行介绍。
本实施例中，逆变器100具体用于将高电压穿越信息编码为脉冲信号，将脉冲信号通过自身的I/O口发送给储能设备200的接口。
逆变器100将高电压穿越信息编码后发送给储能设备200，可以利用逆变器100与储能设备200已经存在的通信接口，即复用已有接口；也可以独立设置一个通信接口。
下面结合图4介绍逆变器复用已有接口的实现方式。
参见图4，该图为本申请实施例提供的另一种逆变器与储能设备的连接示意图。
另外，为了节省逆变器100的硬件接口，逆变器100发送高电压穿越信息的接口可以共用逆变器100中用于向储能设备200发送开机信号的接口，但是储能设备200可以用两个不同的接口均连接逆变器100的同一个I/O口。
逆变器100，还用于通过I/O口将开机信号发送给储能设备200的第二接口B。
储能设备200，用于在收到开机信号时进行开机。
本实施例中储能设备200接收开机信号和接收高电压穿越信息的接口并不相同，分别为第一接口A和第二接口B，因此，储能设备200可以通过接口和信号类型来判断来自逆变器100的信号为开机信号还是高电压穿越信息。另外，在一种可能的实现方式中，储能 设备200接收开机信号和高电压穿越信息的接口也可以为同一个，只要开机信号和高电压穿越信息的信号类型不同即可，例如，开机信号和高电压穿越信息均为方波信号，但是两者对应的方波信号的频率不同，例如开机信号为100Hz的方波信号，高电压穿越信息为200Hz的方波信号。另外，还可以开机信号为脉冲信号，高电压穿越信息为高电平信号。
储能设备200的第一接口A和第二接口B均连接逆变器100的I/O口，即逆变器100的I/O口既用于发送开机信号，又用于发送高电压穿越信息。但是，开机信号和高电压穿越信息的信号格式不同，因此，储能设备200的第一接口A和第二接口B可以分别对收到的信号进行识别，从而确定收到的是开机信号还是高电压穿越信息。当收到的信号为高电压穿越信息时，根据自身处于充电工作状态还是放电工作状态来采取高电压穿越措施。
以上实施例介绍的是储能设备利用两个不同的接口连接逆变器的同一I/O口，应该理解，储能设备也可以仅利用一个接口连接逆变器的I/O口，储能设备通过识别逆变器发送的信号的格式来区分是高电压穿越信号还是开机信号。
下面结合附图介绍储能设备在高电压穿越采取的具体措施。
参见图5，该图为本申请实施例提供的一种储能设备的内部架构图。
本申请实施例提供的储能设备包括：控制器201、功率变换电路202和电池包203。
功率变换电路202的第一端连接电池包203，功率变换电路202的第二端连接直流母线BUS，即储能设备在放电时，功率变换电路202的输出电压便为直流母线的电压，由于功率变换电路202的输出端连接直流母线，即功率变换电路202的输出电压与直流母线的电压一致。
控制器201，用于收到高电压穿越信息且电池包203处于放电工作状态，控制功率变换电路202升高储能设备的输出电压参考值至高电压穿越的峰值电压以上，以使储能设备200继续处于放电工作状态；还用于收到高电压穿越信息且电池包203处于充电工作状态，调整所述储能设备的充电功率参考值为高电压穿越前的充电功率，以使储能设备200继续保持充电工作状态。
本申请实施例中的功率变换电路202可以为双向DC/DC电路，即满足电池包203的充电和放电两种状态。功率变换电路202可以为升压电路，也可以为升降压电路，本申请实施例中不做具体限定。
例如，当储能设备200处于放电工作状态，交流电网发生高电压穿越时，此时直流母线BUS的电压较高，容易反灌到储能设备200中，因此为了不改变储能设备200的放电工作状态，储能设备200需要抬高自身的输出电压参考值，进而才能抬高直流母线BUS的电压。例如，控制器201收到逆变器100发送的高电压穿越信息，控制器201控制功率变换电路202升高输出电压，功率变换电路202将电池包203的电压升高后输出至直流母线BUS。为了保证直流母线上的电流不反灌到储能设备200中，可以将直流母线的电压升高至标准要求的高电压穿越的峰值电压以上，例如1.4倍的额定电压峰值以上。一种可能的实现方式为，控制功率变换电路的输出电压至交流电网的额定电压的预设倍数，预设倍数的取值区间为大于1.4小于2，其中，预设倍数具体可以根据电网的标准要求来确定。其中额定电压是指交流电网的额定电压。应该理解，不同的电网环境，对应的标准可能有所不同，发 生高电压穿越时，需要将直流母线的电压升高至标准要求的高电压穿越的峰值电压以上。
当储能设备200处于充电工作状态，交流电网发生高电压穿越时，储能设备200需要调整所述储能设备的充电功率参考值为与所述高电压穿越前时的充电功率，即保证充电功率与高电压穿越前一致。储能设备200处于充电工作状态时，逆变器为储能设备200中的电池包203充电，但是逆变器可以提供的充电功率可能大于储能设备200需求的功率，也可能逆变器可以提供的充电功率小于储能设备200需求的功率。
当逆变器可以提供的充电功率大于储能设备200需求的功率时，逆变器可以满足储能设备200的充电需求，此时储能设备200的电压控制环路失效，由功率控制环路来控制进行充电。
当逆变器可以提供的充电功率小于储能设备200需求的功率时，储能设备200的电压不会上升，逆变器提供的充电功率全部被储能设备200吸收，此时，储能设备200的电压控制环路起作用，储能设备200的电压控制环路可以控制直流母线BUS的电压。
下面结合附图介绍逆变器发送高电压穿越信息和开机信号复用同一个I/O的具体实现方式。
参见图6，该图为本申请实施例提供的再一种逆变器与储能设备的连接示意图。
本实施例提供的光储系统，逆变器包括：第一光耦合器U1和第二光耦合器U2；
第一光耦合器U1的第一输入端连接逆变器100的I/O口，第一光耦合器U1的第二输出端连接控制器201的第一接口A；第一光耦合器U1的第一输出端通过第三电阻R3连接电源VCC，例如VCC为3.3V。
第二光耦合器U2的第一输入端连接逆变器100的I/O口，第二光耦合器U2的第一输出端连接储能驱动电路300的第一接口B。第二光耦合器U2的第二输出端连接储能驱动电路300的第二接口C。其中储能驱动电路300在收到开机信号时，会驱动储能设备开机。
第一光耦合器U1的第二输入端和第二光耦合器U2的第二输入端均连接参考电位地GND。应该理解，两个光耦合器输入端和输出端对应的地是不同的地，从而实现电气隔离，避免光耦合器输入端的信号对输出端的信号的干扰。
另外，本实施例提供的储能系统还包括第一电阻R1、第二电阻R2和第三电阻R3。其中第一光耦合器U1的第一输入端通过第一电阻R1连接逆变器100的I/O口，同理，第二光耦合器U2的第一输入端通过第二电阻R2连接逆变器100的I/O口，即第一光耦合器U1的第一输入端和第二光耦合器U2的第一输入端均连接逆变器100的I/O口。但是两个光耦合器的输出端连接储能设备的不同输入端。
一种可能的实现方式，以上介绍的两个光耦合器以及外围的电阻和二极管可以与逆变器100集成在一起，即集成在逆变器100的柜体内，而控制器201和储能驱动电路300位于储能设备的一侧，例如可以位于储能集装箱内部。
当逆变器100的I/O口输出高电平时，第一光耦合器U1的第一输入端为高电平，则第一光耦合器U1导通，即第一光耦合器U1的第一输出端与第二输出端导通，即控制器201的第一接口A与VCC接通，即第一接口A收到高电平信号。但是，第二光耦合器U2的第一输出端连接储能驱动电路300的第一接口B，第二光耦合器U2的第二输出端连接储能 驱动电路300的第二接口C，因此，当逆变器100的I/O口输出高电平时，第二光耦合器U2导通，此时第二光耦合器U2的第一输出端与第二输出端接通。
通过以上分析可知，虽然第一光耦合器U1的第一输入端和第二光耦合器U2的第一输入端均连接逆变器100的同一个I/O口，但是在逆变器100的I/O口输出高电平时，第一光耦合器U1和第二光耦合器U2输出的信号并不相同，因此，控制器201和储能驱动电路300接口B可以识别逆变器100发送的是开机信号还是高电压穿越信息。
为了使本领域技术人员更好地理解本申请实施例提供的光储系统在高电压穿越时的措施，下面介绍储能设备正常工作时的工作原理。
参见图7，该图为本申请实施例提供的储能设备充放电的控制环路示意图。
逆变器可以控制储能设备的充放电，实际工作时，逆变器可以通过通信线路向储能设备发送输出电压参考值Vref、充电功率参考值P1ref和放电功率参考值P2ref，储能设备可以根据输出电压参考值Vref、充电功率参考值P1ref和放电功率参考值P2ref控制自身的充放电。
下面分为充电和放电两种工作状态进行介绍。
第一种：充电工作状态
当Vref<直流母线电压Vbus时，储能设备从直流母线吸收能量，给电池包充电，充电原则是储能设备实际的充电功率P1小于等于充电功率参考值P1ref；即充电时，理论上P1不大于P1ref。
当P1>P1ref时，取最小值10对母线电压控制环路L1和充电功率控制环路L2取最小值，将储能设备的充电功率P1限制在充电功率参考值P1ref，即对P1进行限幅处理。
当Vbus＝Vref且P1<P1ref时，储能设备继续从直流母线吸收能量来维持V1＝Vbus的状态。
第二种：放电工作状态
当Vref>Vbus时，储能设备中的电池包为直流母线放电，放电原则是放电功率P2小于等于放电功率参考值P2ref，即放电功率P2不大于放电功率参考值P2ref。
当P2>P2ref时，取最小值20对母线电压控制环路L1和放电功率控制环路L3取最大值(此时充电功率环路达到上限值，因此取最小值10取小值后为母线电压控制环路L1起作用)，将放电功率P2限制在放电功率参考值P2ref，即对P2进行限幅处理；最后的结果需要输出给PWM发波30，即控制功率变换电路工作。
当Vbus＝Vref且P2<P2ref时，储能设备继续放电来维持Vbus＝Vref的状态。
由于交流电网发生高电压穿越时，逆变器的功率升高，此时如果储能设备在放电工作状态，则储能设备只有升高母线电压，才可以继续保持放电工作状态，否则逆变器过高的能量会反灌进电池包，电池包无法继续保持放电工作状态。另外，如果直流母线的电压不升高，则逆变器无法控制自身的输出电流，进而在高电压穿越时，无法使自身的输出电流满足标准的要求，即无法控制并网电流满足高电压穿越的标准要求。储能设备升高直流母线的电压具体可以通过升高输出电压参考值来实现，例如，将输出电压参考值设置为电网标准要求的高电压穿越的峰值电压以上。
如果交流电网发生高电压穿越时，储能设备在充电工作状态，则储能设备要将充电功率参考值调整为高电压穿越时的充电功率，即将高电压穿越前的实际充电功率设定为充电功率参考值。目的是为让储能设备的母线电压控制环路失效，由逆变器来控制直流母线的电压大小。
电源系统实施例
以上实施例介绍的是一种光储系统，应用于光伏发电领域，本申请实施例还提供一种电源系统，不限定具体的应用领域，只要存在逆变器和储能设备即可，并不显得逆变器输入端的电源的来源，例如可以为风力发电，也可以为水利发电等。
参见图8，该图为本申请实施例提供的一种电源系统的示意图。
本申请实施例提供的电源系统，包括：逆变器100和储能设备200；
逆变器100的输入端连接直流母线BUS，逆变器100的输出端用于连接交流电网；
储能设备200连接直流母线BUS。直流母线BUS还用于连接直流电源400。本申请实施例不限定直流电源400的类型，以上实施例中是以直流电源为光伏组串为例进行的介绍，本申请实施例中直流电源400可以为光伏组串以外的其他类型的直流电源。
逆变器100，用于交流电网的电压发生高电压穿越时，向储能设备200发送高电压穿越信息；
储能设备200，用于在收到高电压穿越信息时，如果储能设备200处于放电工作状态则调整输出电压参考值以维持放电工作状态，如果储能设备200处于充电工作状态则调整充电功率参考值以维持充电工作状态。
在一种可能的实现方式中，电源系统还可以包括DC/DC变换器300，如图9所示，DC/DC变换器300的输入端连接直流电源400，DC/DC变换器300的输出端连接直流母线BUS。
具体实现时，逆变器可以将高电压穿越信息编码为脉冲信号，将脉冲信号通过自身的I/O口发送给储能设备的第一接口。此处的脉冲信号可以为方波信号，也可以为电平信号，在此不做具体限定。
为了节省逆变器的硬件接口，逆变器可以复用已有的接口来发送高电压穿越信息，例如复用给储能设备发送开机信号的接口。但是储能设备为了更加准确地区分开机信号和高电压穿越信息，储能设备可以分别利用两个不同的接口来识别高电压穿越信息和开机信号。例如，逆变器通过I/O口将开机信号发送给储能设备的第二接口。
储能设备200还用于在收到开机信号时进行开机。一般是逆变器100先开机，然后逆变器100再控制储能设备200开机。
储能设备一般可以包括：控制器、功率变换电路和电池包。本申请实施例中不限定电池包的具体实现方式，例如电池包可以包括多个电池簇，每个电池簇包括多个电池模组。一般多个电池簇放置在储能集装箱中，多个电池簇通过功率变换电路连接直流母线。
具体实现时，功率变换电路的第一端连接电池包，功率变换电路的第二端连接直流母线。
控制器，用于收到高电压穿越信息且电池包处于放电工作状态，控制功率变换电路升 高储能设备的输出电压参考值至高电压穿越的峰值电压以上，以使储能设备继续处于放电工作状态；还用于收到高电压穿越信息且电池包处于充电工作状态，调整储能设备的充电功率参考值为高电压穿越前的充电功率，以使储能设备继续处于充电工作状态。
本申请实施例中利用逆变器来识别交流电网的电压是否发生高电压穿越，交流电网发生高电压穿越，逆变器需要通知储能设备发生了高电压穿越，以便于储能设备采取高电压穿越的措施，进而使逆变器可以控制并网电网满足高电压穿越的要求。由于传统的交流电网中不存在储能设备，因此，在交流电网出现高电压穿越时，不需要考虑储能设备的工作情况。而光储系统中既包括逆变器，又包括储能设备，因此，交流电网发生高电压穿越时，需要及时通知储能设备。如果由储能设备来识别高电压穿越，一般储能设备通过识别直流母线的电压来判断是否发生了高电压穿越，但是交流电网发生高电压穿越时，直流母线的电压的上升情况与直流母线电容的大小相关，储能设备不能准确通过直流母线的电压上升情况判断是否发生了高电压穿越。本申请实施例由逆变器来识别高电压穿越可以更加准确判定高电压穿越的时刻。
由于交流电网发生高电压穿越时，逆变器的功率升高，此时如果储能设备在放电工作状态，则储能设备只有升高母线电压，才可以继续保持放电工作状态，否则逆变器过高的能量会反灌进电池包，电池包无法继续保持放电工作状态。如果直流母线的电压不升高，则逆变器无法控制自身的输出电流，进而在高电压穿越时，无法使自身的输出电流满足标准的要求，即无法控制并网电流满足高电压穿越的标准要求。储能设备升高直流母线的电压具体可以通过升高输出电压参考值来实现。如果高电压穿越时，储能设备在充电工作状态，则储能设备要将充电功率参考值调整为高电压穿越时的充电功率，即将高电压穿越时的实际充电功率设定为充电功率参考值。目的是为让储能设备的母线电压控制环路失效，由逆变器来控制直流母线的电压大小。
本实施例中介绍的储能设备内部的结构可以参见以上图5的描述，在此不再赘述。
逆变器向储能设备发送的开机信号和高电压穿越信息可以复用同一个I/O口，以上光储系统实施例已经详细进行介绍，下面仅简要说明一种可能的实现方式。
一种可能的实现方式为逆变器包括第一光耦合器和第二光耦合器；第一光耦合器的输入端连接逆变器的I/O口，第一光耦合器的输出端连接储能设备的第一接口；第二光耦合器的输入端连接逆变器的I/O口，第二光耦合器的输出端连接储能设备的第二接口，具体工作原理可以参见以上图6部分的描述，在此不再赘述。
方法实施例
基于以上实施例提供的一种光储系统及电源系统，本申请实施例还提供一种高电压穿越的控制方法，下面结合附图进行详细介绍。
参见图10，该图为本申请实施例提供的一种高电压穿越的控制方法流程图。
本实施例提供的高电压穿越的控制方法，应用于光储系统，光储系统包括逆变器和储能设备；逆变器的输入端用于连接直流母线，储能设备用于连接直流母线，逆变器的输出端用于连接交流电网；
该方法包括：
S1001：接收逆变器发送的高电压穿越信息，逆变器用于通过交流电网的电压判断是否发生高电压穿越，当判断发生高电压穿越时，逆变器向储能设备发送高电压穿越信息，即告知储能设备发生了高电压穿越。
S1002：在收到高电压穿越信息时，如果储能设备处于放电工作状态则调整输出电压参考值以维持放电工作状态，如果储能设备处于充电工作状态则调整充电功率参考值以维持充电工作状态。
储能设备进行高电压穿越时，可以根据自身工作状态采取对应的措施，具体分为以下两种情况。
第一种：储能设备处于放电工作状态；
S1003：收到高电压穿越信息且电池包处于放电工作状态，控制功率变换电路升高所述储能设备的输出电压参考值至标准要求的高电压穿越的峰值电压以上，以使储能设备继续处于放电工作状态。
由于交流电网发生高电压穿越时，逆变器的功率升高，此时如果储能设备在放电工作状态，则储能设备只有升高母线电压，才可以继续保持放电工作状态，否则逆变器过高的能量会反灌进电池包，电池包无法继续保持放电工作状态。如果直流母线的电压不升高，则逆变器无法控制自身的输出电流，进而在高电压穿越时，无法使自身的输出电流满足标准的要求，即无法控制并网电流满足高电压穿越的标准要求。储能设备升高直流母线的电压具体可以通过升高输出电压参考值来实现。
第二种：储能设备处于充电工作状态；
S1004：收到高电压穿越信息且电池包处于充电工作状态，调整储能设备的充电功率参考值为高电压穿越前的充电功率，以使储能设备继续处于充电工作状态。
当发生高电压穿越时，储能设备可以根据自身的工作状态采取对应的措施，例如当储能设备处于放电工作状态时，可以快速升高直流母线的电压，以便继续保持放电工作状态，避免直流母线的电压太高，反灌到储能设备给储能设备中的电池包充电。储能设备抬高直流母线的电压的目的是为了使储能设备保持放电工作状态不变，不频繁在放电和充电之间进行工作状态的切换，而且满足高电压穿越时，逆变器可以按照标准要求输出功率。具体地，储能设备可以通过抬高输出电压来间接抬高直流母线的电压。另外，如果发生高电压穿越时，储能设备处于充电工作状态，则需要调整储能设备的充电功率参考值，以使储能设备继续维持充电工作状态。如果交流电网发生高电压穿越时，储能设备改变工作状态，则影响逆变器控制并网电流，进而不能平稳度过高电压穿越，影响储能设备和逆变器的正常运行，最坏时可能对硬件设备造成损坏。
本申请实施例提供的光储系统，由逆变器来识别交流电网是否发生高电压穿越，当交流电网发生高电压穿越时，逆变器向储能设备发送高电压穿越信息，告知储能设备发生了高电压穿越，以便于储能设备根据自身工作状态，如果储能设备处于放电工作状态则调整输出电压参考值以维持放电工作状态，如果储能设备处于充电工作状态则调整充电功率参考值以维持充电工作状态。本申请实施例中并不是由储能设备自身来识别高电压穿越，从而采取对应的措施。因为储能设备并不能准确判断是否发生高电压穿越，如果发生高电压 穿越时，储能设备没有及时判断出来会使高电压以脉动电流的方式为储能设备充电，导致逆变器无法精确控制并网电流，无法满足交流电网的并网要求。
应当理解，在本申请中，“至少一个(项)”是指一个或者多个，“多个”是指两个或两个以上。“和/或”，用于描述关联对象的关联关系，表示可以存在三种关系，例如，“A和/或B”可以表示：只存在A，只存在B以及同时存在A和B三种情况，其中A，B可以是单数或者复数。字符“/”一般表示前后关联对象是一种“或”的关系。“以下至少一项(个)”或其类似表达，是指这些项中的任意组合，包括单项(个)或复数项(个)的任意组合。例如，a，b或c中的至少一项(个)，可以表示：a，b，c，“a和b”，“a和c”，“b和c”，或“a和b和c”，其中a，b，c可以是单个，也可以是多个。
以上所述，以上实施例仅用以说明本申请的技术方案，而非对其限制；尽管参照前述实施例对本申请进行了详细的说明，本领域的普通技术人员应当理解：其依然可以对前述各实施例所记载的技术方案进行修改，或者对其中部分技术特征进行等同替换；而这些修改或者替换，并不使相应技术方案的本质脱离本申请各实施例技术方案的精神和范围。

Claims (14)

  1. 一种光储系统，其特征在于，包括：逆变器和储能设备；
    所述逆变器的输入端用于连接直流母线，所述逆变器的输出端用于连接交流电网；所述直流母线用于连接光伏组串；
    所述储能设备用于连接所述直流母线；
    所述逆变器，用于所述交流电网的电压发生高电压穿越时，向所述储能设备发送高电压穿越信息；
    所述储能设备，用于在收到所述高电压穿越信息时，如果所述储能设备处于放电工作状态则调整输出电压参考值以维持放电工作状态，如果所述储能设备处于充电工作状态则调整充电功率参考值以维持充电工作状态。
  2. 根据权利要求1所述的光储系统，其特征在于，所述储能设备包括：控制器、功率变换电路和电池包；
    所述功率变换电路的第一端连接所述电池包，所述功率变换电路的第二端连接所述直流母线；
    所述控制器，用于收到所述高电压穿越信息且所述电池包处于所述放电工作状态，所述储能设备向所述直流母线输出能量，控制所述功率变换电路升高所述储能设备的输出电压参考值至高电压穿越的峰值电压以上，以使所述储能设备继续处于所述放电工作状态；还用于收到所述高电压穿越信息且所述电池包处于所述充电工作状态，调整所述储能设备的充电功率参考值为所述高电压穿越前的充电功率，以使所述储能设备继续处于所述充电工作状态。
  3. 根据权利要求1或2所述的光储系统，其特征在于，所述逆变器，具体用于将所述高电压穿越信息编码为脉冲信号，将所述脉冲信号通过自身的I/O口发送给所述储能设备的第一接口。
  4. 根据权利要求3所述的光储系统，其特征在于，还包括：储能驱动电路；
    所述逆变器，还用于通过所述I/O口将开机信号发送给所述储能驱动电路的第一接口；
    所述储能驱动电路，用于在收到所述开机信号时驱动所述储能设备进行开机。
  5. 根据权利要求3或4所述的光储系统，其特征在于，所述逆变器包括：第一光耦合器和第二光耦合器；
    所述第一光耦合器的第一输入端连接所述逆变器的I/O口，所述第一光耦合器的第一输出端连接电源，所述第一光耦合器的第二输出端连接所述储能设备的第一接口；
    所述第二光耦合器的第一输入端连接所述逆变器的I/O口，所述第二光耦合器的输出端连接所述储能驱动电路的第一接口；
    所述第一光耦合器的第二输入端和所述第二光耦合器的第二输入端均连接参考地。
  6. 根据权利要求1-5任一项所述的光储系统，其特征在于，还包括：直流/直流变换器；
    所述直流/直流变换器的输入端用于连接光伏组串；所述直流/直流变换器的输出端用于连接所述直流母线。
  7. 根据权利要求2-6任一项所述的光储系统，其特征在于，所述控制器，具体用于控制 所述功率变换电路的输出电压参考值至所述交流电网的额定电压的预设倍数，所述预设倍数的取值区间为大于1.4小于2。
  8. 一种电源系统，其特征在于，包括：逆变器和储能设备；
    所述逆变器的输入端连接所述直流母线，所述逆变器的输出端用于连接交流电网；
    所述储能设备连接所述直流母线；
    所述逆变器，用于所述交流电网的电压发生高电压穿越时，向所述储能设备发送高电压穿越信息；
    所述储能设备，用于在收到所述高电压穿越信息时，如果所述储能设备处于放电工作状态则调整输出电压参考值以维持放电工作状态，如果所述储能设备处于充电工作状态则调整充电功率参考值以维持充电工作状态。
  9. 根据权利要求8所述的电源系统，其特征在于，所述逆变器，具体用于将所述高电压穿越信息编码为脉冲信号，将所述脉冲信号通过自身的I/O口发送给所述储能设备的第一接口。
  10. 根据权利要求9所述的电源系统，其特征在于，所述逆变器，还用于通过所述I/O口将开机信号发送给所述储能设备的第二接口；
    所述储能设备，用于在收到所述开机信号时进行开机。
  11. 根据权利要求8-10任一项所述的电源系统，其特征在于，所述储能设备包括：控制器、功率变换电路和电池包；
    所述功率变换电路的第一端连接所述电池包，所述功率变换电路的第二端连接所述直流母线；
    所述控制器，用于收到所述高电压穿越信息且所述电池包处于所述放电工作状态，控制所述功率变换电路升高所述储能设备的输出电压参考值至高电压穿越的峰值电压以上，以使所述储能设备继续处于所述放电工作状态；还用于收到所述高电压穿越信息且所述电池包处于所述充电工作状态，调整所述储能设备的充电功率参考值为所述高电压穿越前的充电功率，以使所述储能设备继续处于所述充电工作状态。
  12. 根据权利要求10或11所述的电源系统，其特征在于，所述逆变器包括：第一光耦合器和第二光耦合器；
    所述第一光耦合器的第一输入端连接所述逆变器的I/O口，所述第一光耦合器的第一输出端连接电源，所述第一光耦合器的第二输出端连接所述储能设备的第一接口；
    所述第二光耦合器的第一输入端连接所述逆变器的I/O口，所述第二光耦合器的输出端连接所述储能驱动电路的第一接口；
    所述第一光耦合器的第二输入端和所述第二光耦合器的第二输入端均连接参考地。
  13. 一种高电压穿越的控制方法，其特征在于，应用于光储系统，光储系统包括逆变器和储能设备；所述逆变器的输入端用于连接直流母线，所述储能设备用于连接所述直流母线，所述逆变器的输出端用于连接交流电网；
    该方法包括：
    接收所述逆变器发送的高电压穿越信息，所述逆变器用于判断所述交流电网的电压发 生高电压穿越；
    在收到所述高电压穿越信息时，如果所述储能设备处于放电工作状态则调整输出电压参考值以维持放电工作状态，如果所述储能设备处于充电工作状态则调整充电功率参考值以维持充电工作状态。
  14. 根据权利要求13所述的控制方法，其特征在于，所述根据自身工作状态进行高电压穿越，具体包括：
    收到所述高电压穿越信息且所述电池包处于所述放电工作状态，控制所述功率变换电路升高所述储能设备的输出电压参考值至高电压穿越的峰值电压以上，以使所述储能设备继续处于所述放电工作状态；
    收到所述高电压穿越信息且所述电池包处于所述充电工作状态，调整所述储能设备的充电功率参考值为所述高电压穿越前的充电功率，以使所述储能设备继续处于所述充电工作状态。
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Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116520069B (zh) * 2023-07-04 2023-11-17 上海百竹成航新能源有限责任公司 一种高电压穿越识别方法及其装置、电子设备和储能系统

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102882223A (zh) * 2011-07-11 2013-01-16 陈巍 水风光和生物质多能集成互补发电方法及装置
CN103390901A (zh) * 2013-08-15 2013-11-13 东南大学 风电机组综合串联补偿电压穿越装置及控制方法
CN105322772A (zh) * 2014-06-18 2016-02-10 通用电气公司 用于在不利电压事件期间保护功率转换器的系统和方法
CN105610184A (zh) * 2015-12-02 2016-05-25 成都阜特科技股份有限公司 一种风力发电机组高电压穿越控制方法
US20170187189A1 (en) * 2015-12-28 2017-06-29 King Fahd University Of Petroleum And Minerals Fault ride-through and power smoothing system
WO2018026495A1 (en) * 2016-08-03 2018-02-08 Solarcity Corporation Energy generation and storage system with electric vehicle charging capability
US20180048160A1 (en) * 2016-08-11 2018-02-15 Solarcity Corporation Optimizer battery pv energy generation systems
CN108767843A (zh) * 2018-07-02 2018-11-06 上海大周能源技术有限公司 多端口能量路由器
CN110165705A (zh) * 2019-05-30 2019-08-23 湖南大学 海上双馈风电机组高电压穿越控制方法及系统
CN110572184A (zh) * 2019-08-02 2019-12-13 华为技术有限公司 发电系统及用于发电系统的通信装置
CN112510742A (zh) * 2020-12-15 2021-03-16 西安奇点能源技术有限公司 一种储能系统的高电压穿越模块及其控制方法

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108092601B (zh) * 2016-11-21 2024-05-24 丰郅(上海)新能源科技有限公司 光伏储能逆变一体化系统

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102882223A (zh) * 2011-07-11 2013-01-16 陈巍 水风光和生物质多能集成互补发电方法及装置
CN103390901A (zh) * 2013-08-15 2013-11-13 东南大学 风电机组综合串联补偿电压穿越装置及控制方法
CN105322772A (zh) * 2014-06-18 2016-02-10 通用电气公司 用于在不利电压事件期间保护功率转换器的系统和方法
CN105610184A (zh) * 2015-12-02 2016-05-25 成都阜特科技股份有限公司 一种风力发电机组高电压穿越控制方法
US20170187189A1 (en) * 2015-12-28 2017-06-29 King Fahd University Of Petroleum And Minerals Fault ride-through and power smoothing system
WO2018026495A1 (en) * 2016-08-03 2018-02-08 Solarcity Corporation Energy generation and storage system with electric vehicle charging capability
US20180048160A1 (en) * 2016-08-11 2018-02-15 Solarcity Corporation Optimizer battery pv energy generation systems
CN108767843A (zh) * 2018-07-02 2018-11-06 上海大周能源技术有限公司 多端口能量路由器
CN110165705A (zh) * 2019-05-30 2019-08-23 湖南大学 海上双馈风电机组高电压穿越控制方法及系统
CN110572184A (zh) * 2019-08-02 2019-12-13 华为技术有限公司 发电系统及用于发电系统的通信装置
CN112510742A (zh) * 2020-12-15 2021-03-16 西安奇点能源技术有限公司 一种储能系统的高电压穿越模块及其控制方法

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP4322358A4 *

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