Alternating current coupling energy storage all-in-one machine

Abstract

The utility model discloses an AC coupling energy storage all-in-one machine used for transforming a photovoltaic system, comprising an AC coupling inverter used for connecting a distribution box so as to access the photovoltaic system and a household power grid; the battery management module is connected with the alternating current coupling inverter; the battery module is respectively connected with the alternating current coupling inverter and the battery management module; the energy management module is respectively connected with the alternating current coupling inverter and the battery management module, is used for acquiring the generating capacity of the photovoltaic system, the power consumption of the load and the stored power of the battery module, and can send a control command to the alternating current coupling inverter; and the alternating current coupling inverter is switched between a charging mode and a discharging mode. Installation can be completed only by connecting the alternating current coupling inverter with the distribution box, the installation process is simple, and large-scale circuit modification is avoided. The alternating-current coupling energy storage all-in-one machine flexibly stores redundant electric quantity in a flat valley period and releases the redundant electric quantity in a peak period.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of energy storage system management system, concretely is an alternating coupling energy storage all -in -one. BACKGROUND

[0002] In recent years, with the maturity of photovoltaic power generation technology and policy promotion, more and more families and enterprises install photovoltaic power generation system. However, photovoltaic power generation has significant intermittency and volatility, and is greatly affected by weather conditions and sunshine time. In the strong light of the day, photovoltaic system will generate a large amount of power, but the power demand at this time is usually low, making it difficult to completely consume the generated power. To solve the problem of large photovoltaic system power generation and not being used, the existing several solutions have certain limitations: grid-connected scheme, many photovoltaic systems upload excess power to the grid through grid-connected inverters to realize the secondary utilization of power. But due to the low grid price, the user's benefit is limited. At the same time, some regional power grid companies have certain restrictions on small-scale photovoltaic system grid connection, and may refuse to receive additional power during peak load period of the grid, affecting the economic benefit of the user. Direct current coupling energy storage system, in the direct current coupling system, photovoltaic power is directly stored into the direct current battery module through the controller, and then the direct current is converted into alternating current by the inverter for household use. The direct current coupling system has poor compatibility with the existing photovoltaic system, and the installation is complex and the cost is high. For users who have installed traditional photovoltaic systems, the cost of transformation is large and has great influence on the original system. SUMMARY

[0003] In order to overcome the defects in the prior art, the utility model provides an alternating coupling energy storage all-in-one machine, which only needs to be connected with an alternating coupling inverter and a distribution box to complete the installation, the installation process is simple, the original photovoltaic system does not need to be complicatedly transformed, and large-scale circuit modification is avoided. The alternating coupling energy storage all-in-one machine flexibly stores excess power during flat valley period and releases during peak period.

[0004] To achieve the above purpose, the utility model adopts the technical scheme of an alternating coupling energy storage all-in-one machine for transforming photovoltaic system, comprising:

[0005] An alternating coupling inverter is used to connect a distribution box to access a photovoltaic system and a household power grid.

[0006] A battery management module is connected with the alternating coupling inverter.

[0007] A battery module is connected with the alternating coupling inverter and the battery management module respectively.

[0008] An energy management module is connected with the AC coupling inverter and the battery management module respectively, and is used to acquire the power generation of the photovoltaic system, the power consumption of the load and the storage power of the battery module, and send a control command to the AC coupling inverter to switch the AC coupling inverter between the charging mode and the discharging mode.

[0009] By the above technical solution, the photovoltaic system can be reconstructed only by connecting the AC coupling inverter and the distribution box to access the photovoltaic system and the household power grid, without complex reconstruction of the original photovoltaic system, thereby avoiding large-scale circuit modification. The AC coupling energy storage integrated machine flexibly stores the excess power during the valley period and releases the power during the peak period.

[0010] Further, the AC coupling inverter is connected with a smart meter, and the smart meter is connected with a current transformer, which is used to be sleeved on the power supply line of the household power grid or / and the power supply line of the photovoltaic system. The power generation of the photovoltaic system and the power consumption of the load are detected by the current transformer.

[0011] Further, the battery management module is configured with overcharge protection, overdischarge protection, overheat protection and overcurrent protection submodules.

[0012] The overcharge protection refers to the function of automatically stopping charging when the battery module is full. When the battery module is full, continued charging will cause the voltage of the battery module to rise, which may cause dangerous situations such as overheating and explosion of the equipment. The overcharge protection stops charging in time by monitoring the state of the battery module, thereby protecting the safety of the equipment and the user;

[0013] The overdischarge protection refers to the function of stopping using when the power of the battery module is too low, so as to protect the life and performance of the battery module. When the power of the battery module is too low, continued use will cause the voltage of the battery module to be too low, which may damage the battery module. The overdischarge protection stops using when the power is too low by monitoring the power of the battery module, thereby protecting the performance of the battery module and prolonging its life;

[0014] The overheat protection refers to the function of taking measures to reduce the temperature when the temperature of the equipment is too high. When the equipment is used for a long time or is in a high-temperature environment, it may cause equipment failure, even fire and other dangerous situations. The overheat protection starts the fan to dissipate heat or shuts down the equipment by monitoring the temperature of the equipment once the temperature exceeds the safe range, thereby protecting the safety of the equipment and the user;

[0015] The overcurrent protection refers to the function of automatically interrupting the circuit when the current exceeds the range that can be borne by the equipment. Excessive current may cause dangerous situations such as overheating and short circuit of the equipment. The overcurrent protection cuts off the circuit by monitoring the current once the current exceeding the safe range is detected, thereby protecting the safety of the equipment and the user.

[0016] Further, the energy management module is provided with a network outage protection submodule, the network outage protection submodule comprises a first switch, one end of the first switch is connected to the back-up interface of the AC coupling inverter, the other end of the first switch is connected to a critical load, only when the energy management module detects that the power grid is out of network, the first switch is closed. There are some critical loads in the family or enterprise, such as breathing machine or refrigerator, etc., if these critical loads stop running, a certain loss will be caused, therefore, the AC coupling energy storage all-in-one machine disclosed in the application is provided with a network outage protection submodule, when the power grid is powered off, the AC coupling energy storage all-in-one machine can independently supply power to the above-mentioned critical load.

[0017] Further, the energy management module comprises:

[0018] A photovoltaic power generation amount detection module and a load power consumption detection module, the photovoltaic power generation amount detection module and the load power consumption detection module are connected to the smart meter, if the power amount detected by the photovoltaic power generation amount detection module is greater than the power amount detected by the load power consumption detection module, on the basis of meeting the load power supply demand, the energy management module sends a charging command to the AC coupling inverter, so that the AC coupling inverter charges the battery module. The excess power is stored in the battery module for standby, waste is reduced, and energy utilization rate is improved.

[0019] Further, the energy management module comprises:

[0020] A time period detection module, if the time period detection module detects that the current time period is a peak time period of electricity price, the energy management module sends a discharging command to the AC coupling inverter, so that the AC coupling inverter converts the stored power of the battery module into AC power to supply to the load;

[0021] If the energy management module detects that the battery module storage power is less than a preset value, and the time period detection module detects that the previous time period is a valley time period of electricity price, the energy management module sends a charging command to the AC coupling inverter, so that the AC coupling inverter charges the battery module.

[0022] Through the above-mentioned scheme, the stored energy in the battery module is used to supply power to the load at high electricity price, and the battery module is charged for standby at low electricity price, so as to reduce the electricity cost of the user.

[0023] Further, a cabinet is comprised, the AC coupling inverter, the battery management module, the battery module and the energy management module are all installed in the cabinet. The devices are installed in the cabinet to form an integral whole, when the user uses, the user only needs to connect the AC coupling inverter and the distribution box to access the photovoltaic system and the household power grid, and then the user can use.

[0024] Further, the cabinet comprises a plurality of stacked receiving boxes, each of the receiving boxes is connected through a plug-in connector.

[0025] Further, the bottom of the cabinet is provided with a base, and the base is provided with a grounding wire.

[0026] Further, the energy management module, the AC coupling inverter, the battery management module and the battery module adopt a daisy chain topology structure.

[0027] By the above technical solutions, the beneficial effects of the present application are as follows:

[0028] 1. The AC coupling energy storage all-in-one machine disclosed in the present application has a simple installation process, only needs to connect the AC coupling inverter and the distribution box, and can complete the installation, without the need of complex modification of the original photovoltaic system, and avoids large-scale circuit modification.

[0029] 2. The AC coupling energy storage all-in-one machine disclosed in the present application stores excess power flexibly in the flat valley period through the grid-connected charging sub-module and the grid-connected discharging sub-module, and releases the power in the peak period, so as to reduce the power consumption cost of the user.

[0030] In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the following preferred embodiments are described in detail below, and the accompanying drawings are described as follows. BRIEF DESCRIPTION OF DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiment or the prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0032] Figure 1 is a connection structure schematic diagram of the AC coupling energy storage all-in-one machine in the embodiment of the present application;

[0033] Figure 2 is a connection schematic diagram between the receiving boxes of the AC coupling energy storage all-in-one machine in the embodiment of the present application;

[0034] Figure 3 is a structure schematic diagram of the cabinet of the AC coupling energy storage all-in-one machine in the embodiment of the present application;

[0035] Figure 4 is the side view of the cabinet of the alternating coupling energy storage all-in-one machine in the embodiment of the utility model,

[0036] Figure 5 is the structural schematic view of the cabinet storage box of the alternating coupling energy storage all-in-one machine in the embodiment of the utility model.

[0037] The above figure reference numerals: 1, cabinet;11, first storage box;12, second storage box;121, battery management module;13, third storage box;131, first battery module;14, fourth storage box;15, fifth storage box;2, plug-in connector;3, critical load;4, smart meter;41, first current transformer;42, second current transformer. DETAILED DESCRIPTION

[0038] The technical scheme in the embodiments of the utility model will be described clearly and completely below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor belong to the scope of protection of the utility model.

[0039] It should be noted that in the description of the utility model, the terms "first", "second" and the like are only used for the purpose of description and to distinguish similar objects, and there is no sequence between the two, and it cannot be understood as indicating or implying relative importance. In addition, in the description of the utility model, unless otherwise specified, the meaning of "multiple" is two or more.

[0040] Embodiment: combined Figures 1-5 As shown in the figure, the embodiment discloses an alternating coupling energy storage all-in-one machine for transforming photovoltaic system, comprising:

[0041] Cabinet 1, the cabinet 1 includes multiple stacked storage boxes, including first storage box 11, second storage box 12, third storage box 13, fourth storage box 14 and fifth storage box 15. The first storage box 11, the second storage box 12, the third storage box 13, the fourth storage box 14 and the fifth storage box 15 are connected through the plug-in connector 2, the male head of the plug-in connector 2 of the storage box located in the lower layer is inserted into the female head of the plug-in connector 2 of the storage box located in the upper layer.

[0042] The first storage box 11 is provided with an alternating current coupling inverter, and the side of the first storage box 11 is provided with an opening for exposing an interface of the alternating current coupling inverter. The alternating current coupling inverter is a power electronic device composed of a direct current side switch, an alternating current side switch, an intermediate link inductor, a capacitor and a control circuit, and is mainly used for power conversion and control to realize high-efficiency conversion of alternating current and direct current. The alternating current coupling inverter is used for converting alternating current into direct current and storing excess power generated by photovoltaic in a lithium battery module on the one hand, and converting direct current into alternating current and delivering alternating current to a power grid according to demand to supply power for household loads on the other hand.

[0043] The alternating current coupling inverter is connected with a smart meter 4 through an RS485 port, the smart meter 4 is connected with a first current transformer 41 and a second current transformer 42 respectively, the first current transformer 41 is sleeved on a power supply line of commercial power, and the second current transformer 42 is sleeved on a power supply line of a photovoltaic system.

[0044] The second storage box 12 is provided with a battery management module 121, and the battery management module 121 is connected with the alternating current coupling inverter. The third storage box 13 is provided with a first battery module 131, and the fourth storage box 14 is provided with a second battery module, and the first battery module 131 and the second battery module are connected with the battery management module 121. The battery management module 121 is configured with overcharge protection, overdischarge protection, overheat protection and overcurrent protection functions.

[0045] The overcharge protection refers to a function of automatically stopping charging when the battery module is full. When the battery module is full, continued charging will cause the voltage of the battery module to rise, which may cause overheating, explosion and other dangerous conditions of the equipment. The overcharge protection stops charging in time by monitoring the state of the battery module to protect the safety of the equipment and the user;

[0046] The overdischarge protection refers to a function of stopping use when the battery module has too low power to protect the life and performance of the battery module. When the battery module has too low power, continued use will cause the voltage of the battery module to be too low, which may damage the battery module. The overdischarge protection stops use when the power of the battery module is too low to protect the performance of the battery module and prolong the life of the battery module;

[0047] The overheat protection is a function of taking measures to reduce the temperature when the temperature of the equipment is too high. When the equipment is used for a long time or is in a high-temperature environment, it may cause equipment failure, even fire and other dangerous conditions. The overheat protection monitors the temperature of the equipment, and once the temperature exceeds the safe range, a fan is started to dissipate heat or the equipment is turned off to protect the safety of the equipment and the user;

[0048] The overcurrent protection refers to the function of automatically interrupting the circuit when the current exceeds the range that the device can withstand. Excessive current may cause overheating, short circuit and other dangerous situations of the device. The overcurrent protection monitors the current size, and once it detects that the current exceeds the safe range, it will cut off the circuit to protect the safety of the device and the user.

[0049] Through the above technical solution, the AC coupling inverter, the battery management module 121 and the battery module are respectively arranged in separate receiving boxes, and each module can be independently replaced or repaired.

[0050] The first receiving box 11 also has an energy management module, which includes:

[0051] The photovoltaic power generation detection module and the load power consumption detection module are respectively connected with the smart meter 4, and detect the photovoltaic power generation and the load power consumption through the first current transformer 41 and the second current transformer 42. If the power detected by the photovoltaic power generation detection module is greater than the power detected by the load power consumption detection module, on the basis of meeting the load power supply demand, the energy management module sends a charging command to the AC coupling inverter, so that the AC coupling inverter charges the battery module. Through the photovoltaic power generation detection module and the load power consumption detection module, the photovoltaic power generation and the load power consumption are detected in real time, and the part of the photovoltaic power generation greater than the load power consumption is stored in the battery module for standby, reducing waste and improving energy utilization.

[0052] The time period detection module, if the time period detection module detects that the current time period is a peak period of electricity price, the energy management module sends a discharge command to the AC coupling inverter, so that the AC coupling inverter converts the stored energy of the battery module into alternating current to supply the load;

[0053] If the energy management module detects that the battery module storage power is less than 30%, and the time period detection module detects that the time period before the peak period is a valley period of electricity price, the energy management module sends a charging command to the AC coupling inverter, so that the AC coupling inverter charges the battery module. Through the above scheme, the energy stored in the battery module is used to supply power to the load at high electricity price, and the battery module is charged for standby at low electricity price, reducing the electricity cost of the user.

[0054] The off-grid protection submodule comprises a first switch, one end of the first switch is connected to the back-up interface of the AC coupling inverter, and the other end of the first switch is connected to the critical load 3, and the first switch is closed only when the energy management module detects off-grid of the power grid.

[0055] In the present application, as described above, Figure 2 The energy management module, the AC coupling inverter, the battery management module 121 and the battery module are connected in a daisy chain topology.

[0056] The fifth storage box 15 is provided with a grounding wire. The grounding wire is a line that is connected to the shell of an electrical device and other parts in time to guide the unsafe charge or leakage current generated due to various reasons.

[0057] The AC coupling energy storage all-in-one machine disclosed in the present application is used for reforming an installed photovoltaic system and is suitable for upgrading and expansion of various installed photovoltaic systems. Only by connecting the Grid interface of the AC coupling inverter to the distribution box in the household power grid through a wire harness can the AC coupling inverter be connected to the photovoltaic system and the household power grid, the reform of the photovoltaic system is completed, and complex reform of the original photovoltaic system is not needed, thereby avoiding large-scale circuit modification.

[0058] The principle and implementation mode of the present application are described in the specific embodiments, and the above embodiment is only used for helping to understand the method and core idea of the present application; meanwhile, for those skilled in the art, according to the idea of the present application, the specific implementation mode and application range will be changed, and the above description should not be understood as a limitation of the present application.

Claims

1. An AC coupling energy storage all-in-one for a photovoltaic system, characterized in that, The application relates to a photovoltaic system, which comprises the following parts: an AC coupling inverter used for connecting a distribution box to access a photovoltaic system and a household power grid; a battery management module connected with the AC coupling inverter; a battery module connected with the AC coupling inverter and the battery management module respectively; an energy management module connected with the AC coupling inverter and the battery management module respectively, used for acquiring the power generation of the photovoltaic system, the power consumption of a load and the storage power of the battery module, and capable of sending a control command to the AC coupling inverter to switch the AC coupling inverter between a charging mode and a discharging mode.

2. The AC coupling energy storage all-in-one machine of claim 1, wherein, The AC coupling inverter is connected with a smart meter, and the smart meter is connected with a current transformer used for being sleeved on a power supply line of a commercial power supply or / and a power supply line of the photovoltaic system.

3. The AC coupling energy storage all-in-one machine of claim 1, wherein, The battery management module is provided with overcharge protection, overdischarge protection, overheat protection and overcurrent protection submodules.

4. The AC coupling energy storage all-in-one machine of claim 2, wherein, The energy management module is provided with a network interruption protection submodule, which comprises a first switch, one end of the first switch is connected with a back-up interface of the AC coupling inverter, and the other end of the first switch is connected with a key load. Only when the energy management module detects network interruption, the first switch is closed.

5. The AC coupling energy storage all-in-one machine of claim 4, wherein, The energy management module comprises: a photovoltaic power generation detection module and a load power consumption detection module, both of which are connected with the smart meter. If the power detected by the photovoltaic power generation detection module is greater than the power detected by the load power consumption detection module, on the basis of meeting the power supply demand of the load, the energy management module sends a charging command to the AC coupling inverter to charge the battery module.

6. The AC coupling energy storage all-in-one machine of claim 5, wherein, The energy management module comprises: a time period detection module. If the time period detection module detects that the current time period is a peak time period of electricity price, the energy management module sends a discharging command to the AC coupling inverter to convert the storage power of the battery module into AC power to supply the load. If the energy management module detects that the storage power of the battery module is less than a preset value, and the time period detection module detects that the previous time period is a valley time period of electricity price, the energy management module sends a charging command to the AC coupling inverter to charge the battery module.

7. The AC coupling energy storage all-in-one machine of claim 1, wherein, The application further relates to a cabinet, wherein the AC coupling inverter, the battery management module, the battery module and the energy management module are all installed in the cabinet.

8. The AC coupling energy storage all-in-one machine of claim 7, wherein, The cabinet comprises a plurality of stacking storage boxes, and each of the storage boxes is connected with each other through a plug-in connector.

9. The AC coupling energy storage all-in-one machine of claim 8, wherein, The bottom of the cabinet is provided with a base, and the base is provided with a grounding wire.

10. The AC coupling energy storage all-in-one machine of claim 1, wherein, The energy management module, the AC coupling inverter, the battery management module and the battery module are connected in a daisy chain topology.

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