Intelligent photovoltaic low-voltage grid-connected cabinet

Abstract

The utility model discloses an intelligent photovoltaic low-voltage grid-connected cabinet, and belongs to the technical field of grid-connected cabinets, the intelligent photovoltaic low-voltage grid-connected cabinet comprises a plurality of groups of storage batteries, and each group of storage batteries is correspondingly connected with an inverter; the plurality of inverters are respectively and correspondingly connected with one alternating current contactor for grid connection; the alternating current contactor for grid connection is correspondingly connected with one intermediate relay for grid connection; and the plurality of grid-connected intermediate relays are electrically connected with the PLC. According to the utility model, after the photovoltaic panel generates power, direct current is transmitted to the plurality of groups of storage batteries for storage through wires; the electric quantity monitoring module monitors the electric quantity of the storage battery, after the storage battery is monitored to be full, the storage battery is inverted into alternating current through the inverter, then the alternating current enters the remote control circuit breaker and then is merged into a power grid through the wire outlet end of the remote control circuit breaker, and the electric quantity of the storage battery is judged through electric quantity monitoring. Therefore, intermittent work of the storage battery is realized, and the service life of the storage battery is prevented from being lost due to continuous work.

Description

Technical Field

[0001] The utility model specifically relates to the technical field of grid-connected cabinets, in particular to an intelligent photovoltaic low-voltage grid-connected cabinet. Background Art

[0002] Photovoltaic grid-connected cabinets exist in the photovoltaic system as the total outlet of the photovoltaic power station. Their main function is to serve as the dividing point between the photovoltaic power station and the power grid. For low-voltage grid-connected photovoltaic power stations, photovoltaic grid-connected cabinets can also be equipped with metering and protection devices to facilitate fault inspection and management, and improve the safety and economic benefits of the power generation system.

[0003] Traditional low-voltage grid-connected cabinets simply invert DC power into AC power and then connect it to the grid. The battery is in a continuous working state, which causes great loss to the battery. Long-term operation will cause the battery to heat up, making it impossible to achieve intermittent alternating operation or intelligent switching of power generation and grid connection. Utility Model Content

[0004] The purpose of the utility model is to provide an intelligent photovoltaic low-voltage grid-connected cabinet, which will not continuously output and connect to the grid when a battery is not fully charged, and will only connect to the grid when the battery is fully charged, thereby reducing the working time of the battery, achieving intermittent work, and thus extending the service life of the battery, so as to solve the technical problems raised in the above background technology.

[0005] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0006] An intelligent photovoltaic low-voltage grid-connected cabinet includes a battery, wherein the battery for storing photovoltaic power generation energy is provided with multiple groups, and each group of batteries is connected to a corresponding inverter;

[0007] There are multiple inverters for converting direct current into alternating current; each of the multiple inverters is connected to a corresponding grid-connected AC contactor; each grid-connected AC contactor is connected to a corresponding grid-connected intermediate relay; and the multiple grid-connected intermediate relays are electrically connected to the PLC controller;

[0008] A plurality of grid-connected AC contactors are electrically connected to the three remote-controlled circuit breakers through wires.

[0009] As a further technical solution of the utility model, the power output end of the inverter is connected to the incoming end of the AC contactor for grid connection through a wire; the output end of the inverter is connected to the incoming end of the remote-controlled circuit breaker through a wire, and the output end of the remote-controlled circuit breaker connects the AC power to the grid through a wire.

[0010] As a further technical solution of the utility model, the inlet terminal of the grid-connected intermediate relay is connected to the PLC controller through a wire, and the outlet terminal of the grid-connected intermediate relay is connected to the coil of the grid-connected AC contactor through a wire.

[0011] As a further technical solution of the utility model, it also includes a heat dissipation circuit breaker, a heat dissipation intermediate relay and a temperature sensor; the heat dissipation intermediate relay is electrically connected to the PLC controller and the heat dissipation circuit breaker through wires; the heat dissipation circuit breaker is electrically connected to the heat dissipation fan; and the temperature sensor is electrically connected to the PLC controller.

[0012] As a further technical solution of the utility model, the incoming line end of the heat dissipation circuit breaker is connected in series to the outgoing line ends of multiple grid-connected AC contactors.

[0013] As a further technical solution of the utility model, multiple groups of batteries are installed at the lower end inside the grid-connected cabinet, and are movably connected to a ventilation movable door on the outside, and a cable entry hole is opened on one side of the grid-connected cabinet to facilitate the insertion of photovoltaic cables.

[0014] As a further technical solution of the utility model, the grid-connected AC contactor, grid-connected intermediate relay, remote-controlled circuit breaker, heat dissipation circuit breaker and heat dissipation intermediate relay are all buckled on the mounting clips; there are multiple mounting clips, and both ends are fixed to the side vertical plates; the side vertical plates are fixed to both sides of the inner part of the upper end of the grid-connected cabinet.

[0015] As a further technical solution of the utility model, one side of the upper end of the grid-connected cabinet is movably connected to a cabinet door, and a display screen is embedded on the cabinet door.

[0016] As a further technical solution of the utility model, a plurality of the inverters are installed in an inverter fixing frame; the inverter fixing frame is fixed in a grid-connected cabinet; and the cooling fan is embedded in one side of the grid-connected cabinet.

[0017] Compared with the prior art, the beneficial effects of the utility model are:

[0018] 1. In the utility model, after the photovoltaic panels generate electricity, the direct current is transmitted to multiple groups of batteries through wires for storage; the power monitoring module monitors the power of the battery. When it is detected that the battery is full, it is inverted into alternating current by the inverter, and then enters the remote control circuit breaker, and then connected to the power grid through the outlet of the remote control circuit breaker. The power of the battery is judged by power monitoring. If the power is not full, it will not be output, thereby realizing intermittent operation of the battery and avoiding continuous operation and loss of battery life;

[0019] 2. The utility model provides the grid-connected intermediate relay and the grid-connected AC contactor to achieve the effect of automatic control opening and improve the circuit switching efficiency;

[0020] 3. In the utility model, since the incoming end of the heat dissipation circuit breaker is connected to the outgoing end of multiple grid-connected AC contactors, no matter which battery is inverting or grid-connected power transmission, the heat dissipation fan can be powered on.

[0021] 4. The utility model has three remote control circuit breakers, which are connected to a plurality of grid-connected AC contactors and are connected to the PLC controller via a communication line. When working in grid connection, even if one of the remote control circuit breakers fails, it can be automatically switched to ensure the normal grid connection of electric energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a three-dimensional structural schematic diagram of the utility model.

[0023] Figure 2 This utility model Figure 1 Schematic diagram of the bottom structure.

[0024] Figure 3 This utility model Figure 1 Left view of .

[0025] Figure 4 This utility model Figure 3 AA section view.

[0026] Figure 5 It is a schematic diagram of the circuit structure in the utility model.

[0027] In the figure: 1-battery, 2-inverter, 3-AC contactor for grid connection, 4-intermediate relay for grid connection, 5-remote control circuit breaker, 6-circuit breaker for heat dissipation, 7-intermediate relay for heat dissipation, 8-cooling fan, 9-PLC controller, 10-display screen, 11-cabinet door, 12-grid cabinet, 13-grid threading hole, 14-wire inlet hole, 15-installation card strip, 16-side vertical plate, 17-inverter fixing frame, 18-ventilation movable door, 19-temperature sensor. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0029] See also Figure 1-5 In the embodiment of the utility model, an intelligent photovoltaic low-voltage grid-connected cabinet includes a battery 1, and the battery 1 for storing photovoltaic power generation energy is provided with multiple groups, and each group of batteries 1 is connected to an inverter 2;

[0030] There are multiple inverters 2 for converting direct current into alternating current; each of the multiple inverters 2 is connected to a corresponding grid-connected AC contactor 3; each grid-connected AC contactor 3 is connected to a corresponding grid-connected intermediate relay 4; and the multiple grid-connected intermediate relays 4 are electrically connected to a PLC controller 9;

[0031] The multiple grid-connected AC contactors 3 are electrically connected to the three remote-controlled circuit breakers 5 through wires. The power output end of the inverter 2 is connected to the incoming end of the grid-connected AC contactor 3 through a wire; the outgoing end of the inverter 2 is connected to the incoming end of the remote-controlled circuit breaker 5 through a wire, and the outgoing end of the remote-controlled circuit breaker 5 connects the AC power to the grid through a wire.

[0032] More specifically, a power monitoring module is provided at the output terminal of each storage battery 1 , and the power monitoring module is electrically connected to the PLC controller 9 .

[0033] By adopting the above technical solution: after the photovoltaic panels generate electricity, the direct current is transmitted to multiple groups of batteries 1 through wires for storage (when the photovoltaic panels generate electricity, the current generated by themselves is unstable. The photovoltaic panels use photovoltaic panels with controllers, which can stabilize the voltage and current of the current. This is the existing technology and will not be repeated here); the power monitoring module monitors the power of the battery 1. When it is detected that the battery 1 is full of power, the PLC controller 9 will issue an instruction, and its corresponding grid-connected intermediate relay 4 will be energized and transmit electricity to the coil of the grid-connected AC contactor 3. When the coil of the grid-connected AC contactor 3 is energized, its normally open contact is closed, and the direct current in the battery 1 is converted into alternating current after being inverted by the inverter 2, and then enters the remote control circuit breaker 5, and is finally connected to the power grid through the outlet terminal of the remote control circuit breaker 5.

[0034] In the above scheme, the power level of the storage battery 1 is determined by power monitoring, and no output is performed when the power level is not full, thereby achieving intermittent operation of the storage battery 1 and avoiding continuous operation that would deplete the life of the storage battery 1 .

[0035] In this embodiment, the inlet terminal of the grid-connected intermediate relay 4 is connected to the PLC controller 9 through a wire, and the outlet terminal of the grid-connected intermediate relay 4 is connected to the coil of the grid-connected AC contactor 3 through a wire.

[0036] By adopting the above technical solution, the arrangement of the grid-connected intermediate relay 4 and the grid-connected AC contactor 3 can achieve the effect of automatic control opening, thereby improving the circuit switching efficiency.

[0037] In this embodiment, it also includes a heat dissipation circuit breaker 6, a heat dissipation intermediate relay 7 and a temperature sensor 19; the heat dissipation intermediate relay 7 is electrically connected to the PLC controller 9 and the heat dissipation circuit breaker 6 through wires; the heat dissipation circuit breaker 6 is electrically connected to the heat dissipation fan 8; the temperature sensor 19 is electrically connected to the PLC controller 9.

[0038] By adopting the above technical solution, the temperature sensor 19 can monitor the temperature in the power cabinet 12 and transmit the monitoring information to the PLC controller 9. When the temperature in the power cabinet 12 is high, the PLC controller 9 issues an instruction, the heat dissipation intermediate relay 7 is energized, and the electricity is transmitted to the heat dissipation circuit breaker 6. After the coil of the heat dissipation circuit breaker 6 is energized, its normally open contact is closed, the heat dissipation fan 8 is turned on, and the heat inside the cabinet is dissipated.

[0039] In this embodiment, the incoming end of the heat dissipation circuit breaker 6 is connected in series to the outgoing end of a plurality of grid-connected AC contactors 3 .

[0040] By adopting the above technical solution, since the incoming end of the heat dissipation circuit breaker 6 is connected to the outgoing end of multiple grid-connected AC contactors 3, no matter which battery 1 is inverting or grid-connected to transmit electricity, the heat dissipation fan 8 can be powered on.

[0041] In this embodiment, multiple groups of batteries 1 are installed at the lower end of the grid cabinet 12, and a ventilation movable door 18 is movably connected to the outside, and a cable entry hole 14 is opened on one side of the grid cabinet 12 to facilitate the insertion of photovoltaic cables.

[0042] In this embodiment, the grid-connected AC contactor 3, the grid-connected intermediate relay 4, the remote control circuit breaker 5, the heat dissipation circuit breaker 6 and the heat dissipation intermediate relay 7 are all buckled on the installation clip 15; the installation clip 15 is provided with multiple, and the two ends are fixed to the side vertical plates 16; the side vertical plates 16 are fixed on both sides of the inner part of the upper end of the grid-connected cabinet 12.

[0043] By adopting the above technical solution, the setting of the installation card strip 15 facilitates the installation of the AC contactor 3 for grid connection, the intermediate relay 4 for grid connection, the remote control circuit breaker 5, the heat dissipation circuit breaker 6 and the intermediate relay 7 for heat dissipation, and can also increase or decrease the number of contactors and relays according to the number of batteries 1.

[0044] In this embodiment, one side of the upper end of the grid-connected cabinet 12 is movably connected to a cabinet door 11 , and a display screen 10 is embedded in the cabinet door 11 .

[0045] By adopting the above technical solution, the display screen 10 can display the power level of each battery 1 and the working status of the PLC controller 9.

[0046] In this embodiment, the plurality of inverters 2 are installed in an inverter fixing frame 17 ; the inverter fixing frame 17 is fixed in the grid cabinet 12 ; and the cooling fan 8 is embedded in one side of the grid cabinet 12 .

[0047] In this embodiment, three remote-controlled circuit breakers 5 are provided, all of which are connected to a plurality of grid-connected AC contactors 3 and are connected to a PLC controller 9 via a communication line; when working in grid connection, even if a certain remote-controlled circuit breaker 5 fails, it can be automatically switched to ensure the normal grid connection of electric energy.

[0048] The working principle of the utility model is: after the photovoltaic panels generate electricity, the direct current is transmitted to multiple groups of batteries 1 through wires for storage; the power monitoring module monitors the power of the battery 1. When it is detected that the battery 1 is full of power, the PLC controller 9 will issue an instruction, and its corresponding grid-connected intermediate relay 4 will be energized and transmit the power to the coil of the grid-connected AC contactor 3. When the coil of the grid-connected AC contactor 3 is energized, its normally open contact is closed, and the direct current in the battery 1 is converted into alternating current after being inverted by the inverter 2, and then enters the remote control circuit breaker 5, and is finally connected to the power grid through the outlet terminal of the remote control circuit breaker 5.

[0049] In the above scheme, the power level of the storage battery 1 is determined by power monitoring, and no output is performed when the power level is not full, thereby achieving intermittent operation of the storage battery 1 and avoiding continuous operation that would deplete the life of the storage battery 1 .

[0050] The temperature sensor 19 can monitor the temperature in the power cabinet 12 and transmit the monitoring information to the PLC controller 9. When the temperature in the power cabinet 12 is high, the PLC controller 9 issues an instruction, the heat dissipation intermediate relay 7 is energized, and the electricity is transmitted to the heat dissipation circuit breaker 6. After the coil of the heat dissipation circuit breaker 6 is energized, its normally open contact is closed, the heat dissipation fan 8 is turned on, and the heat in the cabinet is dissipated.

[0051] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

[0052] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. An intelligent photovoltaic low-voltage grid-connected cabinet, characterized in that: include A storage battery (1), wherein the storage battery (1) used for storing photovoltaic power generation energy is provided in a plurality of groups, and each group of storage batteries (1) is connected to a corresponding inverter (2); A plurality of inverters (2) for converting direct current into alternating current are provided; each of the plurality of inverters (2) is connected to a corresponding grid-connected AC contactor (3); each grid-connected AC contactor (3) is connected to a corresponding grid-connected intermediate relay (4); and the plurality of grid-connected intermediate relays (4) are electrically connected to a PLC controller (9); The plurality of grid-connected AC contactors (3) are electrically connected to the three remote-controlled circuit breakers (5) via wires.

2. The intelligent photovoltaic low-voltage grid-connected cabinet according to claim 1 is characterized in that: The power output end of the inverter (2) is connected to the input end of the grid-connected AC contactor (3) through a wire; the output end of the inverter (2) is connected to the input end of the remote-controlled circuit breaker (5) through a wire, and the output end of the remote-controlled circuit breaker (5) connects the AC power to the grid through the wire.

3. The intelligent photovoltaic low-voltage grid-connected cabinet according to claim 1 is characterized in that: The inlet terminal of the grid-connected intermediate relay (4) is connected to the PLC controller (9) via a wire, and the outlet terminal of the grid-connected intermediate relay (4) is connected to the coil of the grid-connected AC contactor (3) via a wire.

4. The intelligent photovoltaic low-voltage grid-connected cabinet according to claim 1 is characterized in that: It also includes a heat dissipation circuit breaker (6), a heat dissipation intermediate relay (7) and a temperature sensor (19); the heat dissipation intermediate relay (7) is electrically connected to the PLC controller (9) and the heat dissipation circuit breaker (6) through wires; the heat dissipation circuit breaker (6) is electrically connected to the heat dissipation fan (8); and the temperature sensor (19) is electrically connected to the PLC controller (9).

5. The intelligent photovoltaic low-voltage grid-connected cabinet according to claim 4 is characterized in that: The inlet terminal of the heat dissipation circuit breaker (6) is connected in series to the outlet terminals of a plurality of grid-connected AC contactors (3).

6. The intelligent photovoltaic low-voltage grid-connected cabinet according to claim 1, characterized in that: A plurality of groups of storage batteries (1) are installed at the lower end of the grid cabinet (12), and are movably connected to a ventilation movable door (18) on the outside, and a cable entry hole (14) is provided on one side of the grid cabinet (12) to facilitate the insertion of photovoltaic cables.

7. The intelligent photovoltaic low-voltage grid-connected cabinet according to claim 1 is characterized in that: The grid-connected AC contactor (3), the grid-connected intermediate relay (4), the remote control circuit breaker (5), the heat dissipation circuit breaker (6) and the heat dissipation intermediate relay (7) are all buckled on the installation clip (15); a plurality of the installation clips (15) are provided, and both ends are fixed to the side vertical plates (16); the side vertical plates (16) are fixed to the two sides inside the upper end of the grid-connected cabinet (12).

8. The intelligent photovoltaic low-voltage grid-connected cabinet according to claim 7 is characterized in that: One side of the upper end of the grid-connected cabinet (12) is also movably connected to a cabinet door (11), and a display screen (10) is embedded in the cabinet door (11).

9. The intelligent photovoltaic low-voltage grid-connected cabinet according to claim 4, characterized in that: The plurality of inverters (2) are installed in an inverter fixing frame (17); the inverter fixing frame (17) is fixed in a grid-connected cabinet (12); and the heat dissipation fan (8) is embedded in one side of the grid-connected cabinet (12).

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