Energy storage converter and energy storage system

Abstract

The invention provides an energy storage converter and an energy storage system, and the energy storage converter comprises a sampling circuit which is used for collecting operation parameters of the energy storage converter, and the operation parameters comprise a first current value of a grid-connected port of the energy storage converter or a second current value of an off-grid port of the energy storage converter; the protection circuit is connected with the sampling circuit and used for reducing the operation power of the target power loop based on the fact that the first current value or the second current value exceeds the corresponding first current threshold value; and turning down the first current threshold value under the condition that the first current value or the second current value exceeds the corresponding second current threshold value, or under the condition that the duration that the first current value or the second current value exceeds the corresponding first current threshold value is greater than or equal to the first duration. By reducing the operation power of the target power loop and lowering the first current threshold, the requirements of the grid-connected regulation at the present stage are met.

Description

Technical Field

[0001] The present invention relates to the field of energy storage technology, and in particular to an energy storage converter and an energy storage system. Background Art

[0002] As a typical intermittent energy source, photovoltaic power generation is affected by many natural factors such as lighting time and solar radiation, and its power generation shows significant intermittency and volatility.

[0003] Therefore, the maximum power of photovoltaic power generation will be greater than the power limit of the power grid. At the same time, when the load power fluctuates, the electricity generated by photovoltaic power generation will also flow into the power grid, thereby exceeding the power limit of the power grid, making photovoltaic power generation unable to meet the requirements of the current grid-connected regulations. Summary of the invention

[0004] The present invention aims to at least solve the technical problem existing in the prior art or related technology that the maximum power of photovoltaic power generation may be greater than the power limit allowed by the power grid, and at the same time, when the load power fluctuates, the electric energy of photovoltaic power generation may also flow to the power grid, thereby exceeding the power limit allowed by the power grid, thereby making photovoltaic power generation unable to meet the requirements of the current grid-connected regulations.

[0005] To this end, a first aspect of the present invention is to provide an energy storage converter.

[0006] A second aspect of the present invention provides an energy storage system.

[0007] In view of this, according to a first aspect of the present invention, the present invention provides an energy storage inverter, comprising: a sampling circuit, for collecting operating parameters of the energy storage inverter, the operating parameters of the energy storage inverter including a first current value of a grid-connected port of the energy storage inverter or a second current value of an off-grid port of the energy storage inverter; a protection circuit, connected to the sampling circuit, for reducing the operating power of a target power circuit based on the first current value or the second current value exceeding the corresponding first current threshold; and lowering the first current threshold when the first current value or the second current value exceeds the corresponding second current threshold, or when the duration for which the first current value or the second current value exceeds the corresponding first current threshold is greater than or equal to the first duration; wherein the second current threshold is greater than the first current threshold, and the target power circuit includes at least one of the following: an inverter power circuit where an inverter circuit in the energy storage inverter is located, an energy storage power circuit of an energy storage component connected to the energy storage inverter, and a photovoltaic power circuit of a photovoltaic component connected to the energy storage inverter.

[0008] The present invention proposes an energy storage converter, which includes a sampling circuit, a protection circuit and an inverter circuit. The sampling circuit is used to collect operating parameters of the energy storage converter during operation, wherein the operating parameters of the energy storage converter include a first current value of the grid-connected port or a second current value of the off-grid port of the energy storage converter, and then the collected first current value or second current value is sent to the protection circuit. After receiving the collected first current value or second current value, the protection circuit compares it with the corresponding first current threshold. If the collected first current value or second current value exceeds the corresponding first current threshold, the power of the grid-connected port is reduced by reducing the operating power of the target power circuit, so as to meet the requirements of the current grid-connected regulations.

[0009] Specifically, if the collected first current value or the second current value exceeds the corresponding first current threshold, it is considered that the operating power of the system where the energy storage inverter is located is too high, which will cause the power value at the grid-connected port to fail to meet the requirements of the current grid-connected regulations. The operating power of the system where the energy storage inverter is located is reduced by reducing the operating power of one or more of the inverter power circuit where the inverter circuit in the energy storage inverter is located, the energy storage power circuit of the energy storage component connected to the energy storage inverter, and the photovoltaic power circuit of the photovoltaic component connected to the energy storage inverter. In this process, power control at the grid-connected port can be achieved at the software level.

[0010] When the first current value or the second current value exceeds the corresponding second current threshold, or when the first current value or the second current value exceeds the corresponding first current threshold for a duration greater than or equal to the first duration, the power control at the grid connection port can be performed from the hardware level by lowering the first current threshold.

[0011] In this technical solution, a method is adopted that combines software control and hardware restriction, wherein software control mainly performs trending, energy scheduling, and slow restriction, while hardware restriction mainly performs fast restriction. The combination of software and hardware restriction can achieve dual restriction of power at the grid-connected port, thereby meeting the requirements of current grid-connected regulations.

[0012] In some technical solutions, the sampling circuit can be constructed according to actual design requirements, such as including a current sampling circuit and a voltage sampling circuit, and its specific topological structure will not be described in detail here.

[0013] In addition, the energy storage converter proposed in this application also has the following additional technical features.

[0014] In some technical schemes, optionally, the protection circuit includes: a comparator, wherein the positive phase input terminal of the comparator is connected to the output terminal of the sampling circuit, the negative phase input terminal of the comparator is used to access the current threshold corresponding to the first current value or the second current value, and the output terminal of the comparator is connected to the inverter circuit; or the negative phase input terminal of the comparator is connected to the output terminal of the sampling circuit, the positive phase input terminal of the comparator is used to access the current threshold corresponding to the first current value or the second current value, and the output terminal of the comparator is connected to the inverter circuit.

[0015] It can be seen from the above technical solution that the protection circuit can compare the collected current value with the corresponding current threshold, and by setting a comparator, the comparator can be used to directly determine the magnitude relationship between the collected current value and the corresponding current threshold.

[0016] Compared with comparison at the software technology level, the use of a comparator for comparison has the characteristic of fast response speed. Therefore, when the detected current value exceeds the corresponding current threshold, the energy storage inverter can quickly reduce the operating power of the target power circuit, thereby realizing rapid adjustment of the operating power of the system where the energy storage inverter is located.

[0017] In the above technical solution, when using the comparator for comparison, different level signals can be output according to the different signals input to the positive input terminal and the negative input terminal of the comparator, thereby meeting the usage needs in different scenarios.

[0018] In some technical solutions, optionally, the first current threshold and the second current threshold are set by a pulse width modulation (PWM) signal.

[0019] In some technical solutions, optionally, the first current threshold and the second current threshold are set by a digital-to-analog converter.

[0020] Among them, the digital-to-analog converter, also known as the D / A converter, or DAC for short, is a device that converts digital quantities into analog quantities.

[0021] In this process, the hardware protection blocking threshold of the grid current, i.e., the first current value and the second current value, is set by pulse width modulation or digital-to-analog converter, so as to limit the grid power at the grid connection port. When the load power changes rapidly and the software level cannot respond quickly, the hardware blocking is triggered to reduce the current, thereby realizing power limitation at the hardware level.

[0022] In some technical schemes, optionally, the energy storage inverter also includes a controller, which is used to: obtain configuration parameters, the configuration parameters include set load power, and the operating parameters of the energy storage inverter also include the load current and load voltage of the off-grid port; determine the load power of the off-grid port based on the load current and load voltage; cut off the power supply output of the load connection port based on the load power of the off-grid port being greater than the set load power; maintain the power supply output of the off-grid port based on the load power of the off-grid port being less than or equal to the set load power.

[0023] In this technical solution, the operating parameters and configuration parameters of the energy storage converter are obtained so as to compare the operating parameters and the configuration parameters, thereby protecting the power grid at the software level.

[0024] Specifically, if the load power of the off-grid port is greater than the set load power, it is considered that the current load power is too high, and the power supply to the load is cut off by cutting off the power output of the load connection port. In this process, the safety of the grid-connected port can be prioritized.

[0025] Specifically, when the load power of the off-grid port is suddenly reduced or the load connected to the off-grid port is directly cut off, the electric energy generated by the photovoltaic module will flow to the grid, thereby triggering the power upper limit of the grid.

[0026] In the technical solution of the present application, if the load power of the off-grid port is greater than the set load power, the power output of the off-grid port can be directly cut off, thereby reducing the impact of the load power fluctuation on the grid-connected power at the grid-connected port, so that the grid-connected power meets the requirements of grid-connected regulations.

[0027] In some technical solutions, optionally, the operating parameters of the energy storage inverter also include the inverter current and inverter voltage of the inverter circuit, the configuration parameters also include the set inverter power, and the controller is also used to: determine the inverter power of the inverter circuit based on the inverter current and the inverter voltage; and reduce the inverter power of the inverter circuit based on the inverter power of the inverter circuit being greater than the set inverter power.

[0028] In this technical solution, if the detected inverter power exceeds the set inverter power, it is considered that the photovoltaic module generates more energy, and more electric energy will flow to the grid, thereby reaching the power upper limit of the grid-connected port.

[0029] By comparing the detected inverter power with the set inverter power, if the detected inverter power is greater than the set inverter power, it is considered that the energy generated by the photovoltaic module will flow to the grid. By reducing the inverter power to limit the power generation power of the photovoltaic module, the probability of triggering the power upper limit of the grid-connected port is reduced, so that the grid-connected power at the grid-connected port meets the requirements of grid-connected regulations.

[0030] In the above technical solution, the inverter power can be set according to the grid-connected regulations, and its maximum value does not exceed the maximum inverter power of the inverter circuit.

[0031] In some technical schemes, optionally, the sampling circuit is also used to collect the photovoltaic current and photovoltaic voltage of the photovoltaic component, the operating parameters of the energy storage inverter also include the grid-connected current and grid-connected voltage of the grid-connected port, and the controller is also used to: determine the power generation power of the photovoltaic component based on the photovoltaic current and the photovoltaic voltage; determine the grid-connected power of the grid-connected port based on the grid-connected current and the grid-connected voltage; based on the power generation power of the photovoltaic component being greater than the first power value, control the photovoltaic component to charge the energy storage component; wherein the first power value is the sum of the load power of the off-grid port and the grid-connected power of the grid-connected port.

[0032] In this technical solution, the power generation of the photovoltaic module is obtained and compared with the load power and the grid-connected power to determine whether there is any surplus power generated by the photovoltaic module. If there is any surplus, the photovoltaic module is used to charge the energy storage module.

[0033] In this process, while realizing load power supply and grid-connected electricity sales, the excess energy is also stored in the energy storage components, making full use of the energy generated by the photovoltaic components, and reducing the waste of green energy while realizing full energy utilization.

[0034] Specifically, the sum of the load power and the grid-connected power is calculated to obtain a first power value. If the generated power is greater than the first power value, it can be determined that the generated power is relatively large, so the photovoltaic component is controlled to charge the energy storage component to store excess energy in the energy storage component to fully utilize the electrical energy generated by the photovoltaic component. In some technical solutions, optionally, the energy storage component is a battery.

[0035] In some technical solutions, optionally, the controller is also used to: reduce the power generation power of the photovoltaic component based on the fact that the power generation power of the photovoltaic component is greater than the first power value and the second power value is greater than the maximum charging power of the energy storage component; wherein the second power value is the power difference between the power generation power of the photovoltaic component and the first power value.

[0036] In this technical solution, if the power generation power of the photovoltaic module is too large, green energy will be wasted. In order to reduce the waste of green energy, in the technical solution of the present invention, the power generation power is compared with the first power value and the maximum charging power. If the power generation power is greater than the first power value and the power difference between the power generation power and the first power value is greater than the maximum charging power, it is considered that the power generation power of the photovoltaic module is too large. At this time, the power generation power is reduced so as to set a reasonable power generation power for the photovoltaic module, thereby reducing the waste of green energy.

[0037] In some technical schemes, optionally, the sampling circuit is also used to collect the energy storage current and energy storage voltage of the energy storage component, and the controller is also used to: determine the operating power of the energy storage component based on the energy storage current and the energy storage voltage; based on the fact that the power generation power of the photovoltaic component is less than the first power value, adjust the operating power of the energy storage component to a third power value, and control the energy storage component to output power according to the third power value; wherein, the sum of the power generation power of the photovoltaic component and the third power value is equal to the first power value.

[0038] In this technical solution, if the power generated by the photovoltaic module is insufficient to meet the power requirements of the load and the grid-connected port, the energy storage module can be controlled to output power. At this time, the photovoltaic module and the energy storage module output power at the same time to ensure the power supply needs of the load and / or the power selling needs of the grid-connected port.

[0039] In this process, the third power is the power difference between the first power value and the generated power. Obviously, in the technical solution of the present invention, energy storage components are used to make up for the insufficient power supply. Therefore, the technical solution of the present invention achieves full utilization of energy while ensuring the load power supply and electricity selling needs.

[0040] In some technical solutions, optionally, the controller is also used to: obtain a first grid-connected standard, where the first grid-connected standard is a grid-connected standard of a grid-connected port; and obtain configuration parameters based on the first grid-connected standard.

[0041] In this technical solution, the configuration parameters are not fixed, but are determined according to the grid-connected standard of the energy storage inverter currently connected to the grid-connected port. In this process, the corresponding configuration parameters can be selected according to the connected grid-connected standard, so that the energy storage inverter can meet the power control requirements in different scenarios, and then meet the corresponding grid-connected regulations.

[0042] According to a second aspect of the present invention, the present invention provides an energy storage system, comprising: an energy storage converter as described in any one of the above.

[0043] In some technical solutions, optionally, the energy storage system further includes: a photovoltaic component and an energy storage component, and the photovoltaic component and the energy storage component are respectively connected to the energy storage inverter.

[0044] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0046] Figure 1 One of the connection schematic diagrams of an energy storage converter according to an embodiment of the present invention is shown;

[0047] Figure 2 The second connection diagram of an energy storage converter in an embodiment of the present invention is shown:

[0048] Figure 3 A connection diagram of an energy storage system in an embodiment of the present invention is shown.

[0049] in, Figures 1 to 3 The corresponding relationship between the reference numerals and the component names is as follows:

[0050] 100 energy storage converter, 102 sampling circuit, 104 protection circuit, 1042 comparator, 106 inverter circuit, 108 controller, 200 photovoltaic module, 300 energy storage module, 400 energy storage system. DETAILED DESCRIPTION

[0051] In order to more clearly understand the above aspects, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0052] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0053] In one embodiment of the present application, Figure 1 , Figure 2 and Figure 3 As shown, an energy storage converter 100 is provided, including: a sampling circuit 102, for collecting operating parameters of the energy storage converter 100, the operating parameters of the energy storage converter 100 including a first current value of a grid-connected port of the energy storage converter 100 or a second current value of an off-grid port of the energy storage converter 100; a protection circuit 104, connected to the sampling circuit 102, for reducing the operating power of a target power circuit based on the first current value or the second current value exceeding the corresponding first current threshold; and lowering the first current threshold when the first current value or the second current value exceeds the corresponding second current threshold, or when the duration of the first current value or the second current value exceeding the corresponding first current threshold is greater than or equal to the first duration; wherein the second current threshold is greater than the first current threshold, and the target power circuit includes at least one of the following: an inverter power circuit where an inverter circuit 106 in the energy storage converter 100 is located, an energy storage power circuit of an energy storage assembly 300 connected to the energy storage converter 100, and a photovoltaic power circuit of a photovoltaic assembly 200 connected to the energy storage converter 100.

[0054] The present invention proposes an energy storage converter 100, which includes a sampling circuit 102, a protection circuit 104 and an inverter circuit 106. The sampling circuit 102 is used to collect operating parameters of the energy storage converter 100 during operation, wherein the operating parameters of the energy storage converter 100 include a first current value of a grid-connected port or a second current value of an off-grid port of the energy storage converter 100, and then the collected first current value or the second current value is sent to the protection circuit 104. After receiving the collected first current value or the second current value, the protection circuit 104 compares it with the corresponding first current threshold. If the collected first current value or the second current value exceeds the corresponding first current threshold, the power of the grid-connected port is reduced by reducing the operating power of the target power circuit, so as to meet the requirements of the current grid-connected regulations.

[0055] Specifically, if the collected first current value or the second current value exceeds the corresponding first current threshold, it is considered that the operating power of the system where the energy storage inverter 100 is located is too high, which will cause the power value at the grid-connected port to fail to meet the requirements of the current grid-connected regulations. By reducing the operating power of one or more of the inverter power circuit where the inverter circuit 106 in the energy storage inverter 100 is located, the energy storage power circuit of the energy storage component 300 connected to the energy storage inverter 100, and the photovoltaic power circuit of the photovoltaic component 200 connected to the energy storage inverter 100, the operating power of the system where the energy storage inverter 100 is located can be reduced. In this process, power control at the grid-connected port can be achieved at the software level.

[0056] When the first current value or the second current value exceeds the corresponding second current threshold, or when the first current value or the second current value exceeds the corresponding first current threshold for a duration greater than or equal to the first duration, the power control at the grid connection port can be performed from the hardware level by lowering the first current threshold.

[0057] In this technical solution, a method is adopted that combines software control and hardware restriction, wherein software control mainly performs trending, energy scheduling, and slow restriction, while hardware restriction mainly performs fast restriction. The combination of software and hardware restriction can achieve dual restriction of power at the grid-connected port, thereby meeting the requirements of current grid-connected regulations.

[0058] In some embodiments, optionally, the grid-connected port may be a connection port for connecting the energy storage converter 100 to the grid, and the off-grid port may be understood as a connection port for connecting to the load.

[0059] In some embodiments, the sampling circuit 102 can be constructed according to actual design requirements, such as including a current sampling circuit and a voltage sampling circuit, and its specific topological structure will not be described in detail here.

[0060] In some embodiments, optionally, the protection circuit 104 includes: a comparator 1042, wherein the positive phase input terminal of the comparator 1042 is connected to the output terminal of the sampling circuit 102, the negative phase input terminal of the comparator 1042 is used to access the current threshold corresponding to the first current value or the second current value, and the output terminal of the comparator 1042 is connected to the inverter circuit 106; or the negative phase input terminal of the comparator 1042 is connected to the output terminal of the sampling circuit 102, the positive phase input terminal of the comparator 1042 is used to access the current threshold corresponding to the first current value or the second current value, and the output terminal of the comparator 1042 is connected to the inverter circuit 106.

[0061] It can be seen from the above embodiments that the protection circuit 104 can compare the collected current value with the corresponding current threshold, and by providing the comparator 1042 , the comparator 1042 can be used to directly determine the magnitude relationship between the collected current value and the corresponding current threshold.

[0062] The use of comparator 1042 for comparison has the characteristic of fast response speed compared to the comparison at the software technology level. Therefore, when the detected current value exceeds the corresponding current threshold, the energy storage inverter 100 can quickly reduce the operating power of the target power circuit, thereby realizing rapid adjustment of the operating power of the system where the energy storage inverter 100 is located.

[0063] In the above embodiment, when the comparator 1042 is used for comparison, different level signals can be output according to the difference in the signals input to the positive input terminal and the negative input terminal of the comparator 1042, thereby meeting the usage requirements in different scenarios.

[0064] In some embodiments, optionally, the first current threshold and the second current threshold are set by a pulse width modulation (PWM) signal.

[0065] In some embodiments, optionally, the first current threshold and the second current threshold are set by a digital-to-analog converter.

[0066] Among them, the digital-to-analog converter, also known as the D / A converter, or DAC for short, is a device that converts digital quantities into analog quantities.

[0067] In this process, the hardware protection blocking threshold of the grid current, i.e., the first current value and the second current value, is set by pulse width modulation or digital-to-analog converter, so as to limit the grid power at the grid connection port. When the load power changes rapidly and the software level cannot respond quickly, the hardware blocking is triggered to reduce the current, thereby realizing power limitation at the hardware level.

[0068] In some embodiments, optionally, the energy storage inverter 100 also includes a controller 108, which is used to: obtain configuration parameters, the configuration parameters include setting load power, and the operating parameters of the energy storage inverter 100 also include the load current and load voltage of the off-grid port; determine the load power of the off-grid port based on the load current and the load voltage; cut off the power supply output of the off-grid port based on the load power of the off-grid port being greater than the set load power; maintain the power supply output of the off-grid port based on the load power of the off-grid port being less than or equal to the set load power.

[0069] In this embodiment, the operating parameters and configuration parameters of the energy storage converter 100 are obtained so as to compare the operating parameters and the configuration parameters, thereby protecting the power grid at the software level.

[0070] Specifically, if the load power of the off-grid port is greater than the set load power, it is considered that the current load power is too high, and the power supply output of the off-grid port is cut off to cut off the power supply to the load. In this process, the safety of the grid-connected port can be prioritized.

[0071] Specifically, when the load power of the off-grid port is suddenly reduced or the load connected to the off-grid port is directly cut off, the electric energy generated by the photovoltaic module will flow to the grid, thereby triggering the power upper limit of the grid.

[0072] In an embodiment of the present application, if the load power of the off-grid port is greater than the set load power, the power output of the off-grid port can be directly cut off, thereby reducing the impact of load power fluctuations on the grid-connected power at the grid-connected port, so that the grid-connected power meets the requirements of grid-connected regulations.

[0073] Among them, cutting off the power supply output of the off-grid port can be understood as stopping the power supply to the load.

[0074] In some embodiments, optionally, the operating parameters of the energy storage inverter 100 also include the inverter current and inverter voltage of the inverter circuit 106, and the configuration parameters also include the set inverter power. The controller 108 is also used to: determine the inverter power of the inverter circuit based on the inverter current and the inverter voltage; and reduce the inverter power of the inverter circuit based on the inverter power of the inverter circuit being greater than the set inverter power.

[0075] In this embodiment, if the detected inverter power exceeds the set inverter power, it is considered that the energy generated by the photovoltaic assembly increases, and the increased electric energy will flow to the grid, thereby reaching the power upper limit of the grid-connected port.

[0076] By comparing the detected inverter power with the set inverter power, if the detected inverter power is greater than the set inverter power, it is considered that the energy generated by the photovoltaic module will flow to the grid. By reducing the inverter power, the energy generated by the photovoltaic module can be limited, thereby reducing the probability of triggering the power upper limit of the grid-connected port, so that the grid-connected power at the grid-connected port meets the requirements of grid-connected regulations.

[0077] In the above embodiment, the inverter power may be set according to grid-connected regulations, and its maximum value does not exceed the maximum inverter power of the inverter circuit 106 .

[0078] In some embodiments, optionally, the sampling circuit 102 is also used to collect the photovoltaic current and photovoltaic voltage of the photovoltaic component 200, the operating parameters of the energy storage inverter 100 also include the grid-connected current and grid-connected voltage of the grid-connected port, and the controller 108 is also used to: based on the fact that the power generation power of the photovoltaic component 200 is greater than the first power value, control the photovoltaic component 200 to charge the energy storage component 300; wherein the first power value is the sum of the load power of the off-grid port and the grid-connected power of the grid-connected port.

[0079] In this embodiment, the power generation of the photovoltaic component 200 is obtained and compared with the load power and the grid-connected power to determine whether there is any surplus power generated by the photovoltaic component 200. If there is any surplus, the photovoltaic component 200 is used to charge the energy storage component 300.

[0080] In this process, while realizing load power supply and grid-connected electricity sales, the excess energy is also stored in the energy storage component 300, and the energy generated by the photovoltaic component 200 is fully utilized, thereby realizing full utilization of energy and reducing the waste of green energy.

[0081] Specifically, the sum of the load power and the grid-connected power is calculated to obtain a first power value. If the generated power is greater than the first power value, it can be determined that the generated power is relatively large, so the photovoltaic component 200 is controlled to charge the energy storage component 300 to store excess energy in the energy storage component 300 to fully utilize the electrical energy generated by the photovoltaic component 200.

[0082] In some embodiments, optionally, the energy storage component 300 is a battery.

[0083] In some embodiments, optionally, the controller 108 is also used to: reduce the power generation power of the photovoltaic component 200 based on the fact that the power generation power of the photovoltaic component 200 is greater than the first power value and the second power value is greater than the maximum charging power of the energy storage component 300; wherein the second power value is the power difference between the power generation power of the photovoltaic component 200 and the first power value.

[0084] In this embodiment, if the power generation power of the photovoltaic component 200 is too large, green energy will be wasted. In order to reduce the waste of green energy, in an embodiment of the present invention, the power generation power is compared with the first power value and the maximum charging power. If the power generation power is greater than the first power value and the power difference between the power generation power and the first power value is greater than the maximum charging power, it is considered that the power generation power of the photovoltaic component 200 is too large. At this time, the power generation power is reduced so as to set a reasonable power generation power for the photovoltaic component 200, thereby reducing the waste of green energy.

[0085] In some embodiments, optionally, the sampling circuit 102 is also used to collect the energy storage current and energy storage voltage of the energy storage component 300, and the controller 108 is also used to: determine the operating power of the energy storage component 300 based on the energy storage current and the energy storage voltage; based on the fact that the power generation power of the photovoltaic component 200 is less than the first power value, adjust the operating power of the energy storage component 300 to a third power value, and control the energy storage component 300 to output power according to the third power value; wherein, the sum of the power generation power of the photovoltaic component 200 and the third power value is equal to the first power value.

[0086] In this embodiment, if the power generation power of the photovoltaic component 200 is insufficient to meet the power requirements of the load and the grid-connected port, the energy storage component 300 can be controlled to output power. At this time, the photovoltaic component 200 and the energy storage component 300 output power at the same time to ensure the power supply needs of the load and / or the power selling needs of the grid-connected port.

[0087] In this process, the third power is the power difference between the first power value and the generated power. Obviously, in the embodiment of the present invention, the energy storage component 300 is used to make up for the insufficient power supply. Therefore, the embodiment of the present invention achieves full utilization of energy while ensuring the load power supply and electricity selling needs.

[0088] In some embodiments, optionally, the controller 108 is further used to: obtain a first grid-connected standard, where the first grid-connected standard is a grid-connected standard for access to the grid-connected port; and obtain configuration parameters based on the first grid-connected standard.

[0089] In this embodiment, the configuration parameters are not fixed, but are determined according to the grid-connected standard of the grid-connected port to which the energy storage inverter 100 is currently connected. In this process, the corresponding configuration parameters can be selected according to the connected grid-connected standard, so that the energy storage inverter 100 can meet the power control requirements in different scenarios, and thus meet the corresponding grid-connected regulatory requirements.

[0090] In some embodiments, the grid-connected standard power grid is determined by the region or country where the grid is located, and may also be provided by the power company to which the grid belongs.

[0091] In one embodiment, the present invention provides an energy storage system 400, comprising: an energy storage converter 100 as described in any one of the above.

[0092] In some embodiments, optionally, the energy storage system 400 further includes: a photovoltaic component 200 and an energy storage component 300 , and the photovoltaic component 200 and the energy storage component 300 are respectively connected to the energy storage converter 100 .

[0093] The term "first" or "second" in the specification and claims of the present application may include one or more of the features explicitly or implicitly. In the textual description of the present invention, unless otherwise specified, "plurality" means two or more. In addition, "and / or" in the specification and claims means at least one of the connected objects, and the character " / " generally means that the objects connected before and after are in an "or" relationship.

[0094] In the text description of the present invention, it is understood that, except for explicit provisions and limitations, the terms "installation", "connection" and "connection" should be understood in a broad sense. For example, it can be fixed connection, detachable connection, or integral connection; it can be mechanical structure connection or electrical connection; it can be direct connection between the two, or indirect connection between the two through an intermediate medium, or it can be internal communication between two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0095] In the claims, specification and drawings of the present invention, the description of the terms "one embodiment", "some embodiments", "specific embodiments" and the like means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In the claims, specification and drawings of the present invention, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0096] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An energy storage converter, characterized in that: include: A sampling circuit, used for collecting operating parameters of the energy storage converter, wherein the operating parameters of the energy storage converter include a first current value of a grid-connected port of the energy storage converter or a second current value of an off-grid port of the energy storage converter; a protection circuit connected to the sampling circuit, and configured to reduce the operating power of a target power circuit based on the first current value or the second current value exceeding a corresponding first current threshold; as well as When the first current value or the second current value exceeds the corresponding second current threshold, or when the first current value or the second current value exceeds the corresponding first current threshold for a duration greater than or equal to a first duration, lowering the first current threshold; Wherein, the second current threshold is greater than the first current threshold, and the target power loop includes at least one of the following: The inverter power circuit where the inverter circuit in the energy storage converter is located, the energy storage power circuit of the energy storage component connected to the energy storage converter, and the photovoltaic power circuit of the photovoltaic component connected to the energy storage converter.

2. The energy storage converter according to claim 1, characterized in that: The protection circuit comprises: A comparator, wherein the positive input terminal of the comparator is connected to the output terminal of the sampling circuit, the negative input terminal of the comparator is used to access the current threshold corresponding to the first current value or the second current value, and the output terminal of the comparator is connected to the inverter circuit; or The negative phase input terminal of the comparator is connected to the output terminal of the sampling circuit, the positive phase input terminal of the comparator is used to access the current threshold corresponding to the first current value or the second current value, and the output terminal of the comparator is connected to the inverter circuit.

3. The energy storage converter according to claim 1 or 2, characterized in that: The energy storage converter further includes a controller, which is used for: Acquire configuration parameters, wherein the configuration parameters include setting load power, and the operating parameters of the energy storage converter also include load current and load voltage of the off-grid port; Determine the load power of the off-grid port based on the load current and the load voltage; Cutting off the power supply output of the off-grid port based on the load power of the off-grid port being greater than the set load power; Based on the load power of the off-grid port being less than or equal to the set load power, the power supply output of the off-grid port is maintained.

4. The energy storage converter according to claim 3, characterized in that: The operating parameters of the energy storage converter also include the inverter current and the inverter voltage of the inverter circuit, the configuration parameters also include setting the inverter power, and the controller is further used for: determining an inverter power of the inverter circuit based on the inverter current and the inverter voltage; Based on the fact that the inverter power of the inverter circuit is greater than the set inverter power, the inverter power of the inverter circuit is reduced.

5. The energy storage converter according to claim 3, characterized in that: The sampling circuit is also used to collect the photovoltaic current and photovoltaic voltage of the photovoltaic assembly. The operating parameters of the energy storage converter also include the grid-connected current and grid-connected voltage of the grid-connected port. The controller is also used to: Determining the power generation power of the photovoltaic assembly based on the photovoltaic current and the photovoltaic voltage; Determine the grid-connected power of the grid-connected port based on the grid-connected current and the grid-connected voltage; Based on the fact that the power generation power of the photovoltaic component is greater than the first power value, controlling the photovoltaic component to charge the energy storage component; The first power value is the sum of the load power of the off-grid port and the grid-connected power of the grid-connected port.

6. The energy storage converter according to claim 5, characterized in that: The controller is also used for: Based on the fact that the power generation power of the photovoltaic assembly is greater than the first power value and the second power value is greater than the maximum charging power of the energy storage assembly, reducing the power generation power of the photovoltaic assembly; The second power value is the power difference between the power generation power of the photovoltaic component and the first power value.

7. The energy storage converter according to claim 6, characterized in that: The sampling circuit is also used to collect the energy storage current and energy storage voltage of the energy storage component, and the controller is also used to: determining an operating power of the energy storage component based on the energy storage current and the energy storage voltage; Based on the fact that the power generation power of the photovoltaic component is less than the first power value, adjusting the operating power of the energy storage component to a third power value, and controlling the energy storage component to output power according to the third power value; The sum of the power generation power of the photovoltaic module and the third power value is equal to the first power value.

8. The energy storage converter according to claim 3, characterized in that: The controller is also used for: Acquire a first grid-connection standard, where the first grid-connection standard is the grid-connection standard of the grid-connection port; The configuration parameters are acquired based on the first grid connection standard.

9. An energy storage system, characterized in that: include: The energy storage converter according to any one of claims 1 to 8.

10. The energy storage system according to claim 9, characterized in that: Also includes: A photovoltaic component and an energy storage component, wherein the photovoltaic component and the energy storage component are respectively connected to the energy storage converter.

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