CN211556872U

CN211556872U - Grid-connected and off-grid integrated household energy storage system

Info

Publication number: CN211556872U
Application number: CN202020618518.2U
Authority: CN
Inventors: 陈国涛; 沈宏涛; 罗进
Original assignee: Sichuan Electric Power Design and Consulting Co Ltd
Current assignee: Sichuan Electric Power Design and Consulting Co Ltd
Priority date: 2020-04-22
Filing date: 2020-04-22
Publication date: 2020-09-22
Anticipated expiration: 2030-04-22

Abstract

The utility model provides a can realize multi-functional, multi-mode and from domestic energy storage system of net integration, relate to electricity generation energy storage system technical field. The utility model discloses a and domestic energy storage system of off-grid integration, photovoltaic module with one-way DC converter input electricity is connected, one-way DC converter output pass through direct current bus with DC AC prevents that two-way DC-to-AC converter direct current end electricity is connected against the current, DC AC prevents that two-way DC-to-AC converter alternating current end with second switch one end electricity is connected, the second switch other end through 220V alternating current bus with the one end electricity of first switch is connected, first switch other end electricity is connected on the public network. The system meets the requirements of users and realizes the maximization of user benefits.

Description

Grid-connected and off-grid integrated household energy storage system

Technical Field

The utility model relates to a power generation energy storage system technical field, in particular to and domestic energy storage system of integration from net.

Background

Solar energy is a novel energy source which is ubiquitous, rich in resources and free of pollution. Solar energy is considered to be one of the best choices for human to replace traditional fossil energy in the 21 st century because of its abundant, widely distributed, safe and clean resources. However, the photovoltaic power generation system is not without defects, and solar energy is not a continuous energy source and is influenced by factors such as weather, so that the photovoltaic power generation system cannot generate power continuously. With the increasing perfection of photovoltaic power generation technology and the continuous reduction of equipment cost, photovoltaic energy storage systems have entered common families. The household energy storage system needs to consider maximum utilization of solar energy, cannot cause overlarge voltage fluctuation of a public network, but most of the conventional energy storage systems have single functions, less operation modes and no off-network operation mode, so that the access requirement under the condition of a special power grid cannot be met.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problem that a can realize multi-functional, multi-mode and from domestic energy storage system of net integration is provided.

The utility model provides a technical scheme that its technical problem adopted is: a grid-connected and off-grid integrated household energy storage system comprises a photovoltaic assembly, a storage battery, a unidirectional DC/DC converter, a bidirectional DC/DC converter, a DC/DC power converter, a DC/AC anti-reflux bidirectional inverter, a first switch, a second switch, a direct current load and an alternating current load;

the photovoltaic module is electrically connected with the input end of the unidirectional DC/DC converter, the output end of the unidirectional DC/DC converter is electrically connected with the direct current end of the DC/AC anti-reflux bidirectional inverter through a direct current bus, the alternating current end of the DC/AC anti-reflux bidirectional inverter is electrically connected with one end of the second switch, the other end of the second switch is electrically connected with one end of the first switch through a 220V alternating current bus, and the other end of the first switch is electrically connected to a public network;

one end of the bidirectional DC/DC converter is connected with the input end of the DC/DC power converter in parallel on the direct current bus, the direct current load is electrically connected with the output end of the DC/DC power converter, the storage battery is electrically connected with the other end of the bidirectional DC/DC converter, and the alternating current load is connected with the 220V alternating current bus in parallel.

Further, the alternating-current power supply further comprises a third switch which is arranged between the alternating-current load and the 220V alternating-current bus and used for controlling the 220V alternating-current bus to be powered on or powered off to the alternating-current load.

Further, the first switch, the second switch and the third switch are all relays.

Further, the DC/DC power converter is provided with a plurality of output terminals having different output voltages.

Further, the DC/DC power converter output includes an output, and an output.

The utility model has the advantages that: when the public power grid fails and stops supplying power, the system can be converted into an off-grid mode to independently operate and still supply power to a local load, and continuous work of important equipment is guaranteed, so that the reliability and the convenience of power supply are higher, meanwhile, the system and the public power grid are mutually supported (grid-connected mode), so that the capacity of a storage battery can be effectively reduced according to actual power grid conditions and the power consumption of the important load, the system construction cost can be greatly reduced, multiple operation working conditions can be realized in the grid-connected mode, the photovoltaic module is enabled to be fully utilized for power generation, the requirements of users are met, and the benefit maximization of the users is realized.

Drawings

Fig. 1 is a schematic structural diagram of the present invention;

shown in the figure: the photovoltaic module comprises a photovoltaic module 1, a unidirectional DC/DC converter 2, a bidirectional DC/DC converter 3, a storage battery 4, a direct current load 5, a DC/DC power converter 6, a direct current bus 7, a DC/AC anti-backflow bidirectional inverter 8, a second switch 9, a third switch 10, an alternating current load 11, a 220V alternating current bus 12 and a first switch 13.

Detailed Description

The present invention will be further explained with reference to the drawings and examples.

As shown in fig. 1, the utility model discloses a grid-connected and off-grid integrated household energy storage system, including photovoltaic module 1, battery 4, still include one-way DC/DC converter 2, two-way DC/DC converter 3, DC/DC power converter 6, DC/AC prevent two-way inverter 8 against current, first switch 13, second switch 9, direct current load 5 and alternating current load 11.

The photovoltaic module 1 is electrically connected with the input end of the unidirectional DC/DC converter 2, the output end of the unidirectional DC/DC converter 2 is electrically connected with the direct current end of the DC/AC anti-reflux bidirectional inverter 8 through a direct current bus 7, the alternating current end of the DC/AC anti-reflux bidirectional inverter 8 is electrically connected with one end of the second switch 9, the other end of the second switch 9 is electrically connected with one end of the first switch 13 through a 220V alternating current bus 12, and the other end of the first switch 13 is electrically connected on a public network 14.

One end of the bidirectional DC/DC converter 3 is connected with the input end of the DC/DC power converter 6 in parallel on the direct current bus 7, the direct current load 5 is electrically connected with the output end of the DC/DC power converter 6, the storage battery 4 is electrically connected with the other end of the bidirectional DC/DC converter 3, and the alternating current load 11 is connected with the 220V alternating current bus 12 in parallel.

The direct current load and the alternating current load are household electrical appliances.

And (3) closing the first switch 13 and the second switch 9, and closing the reverse flow prevention switch on the DC/AC reverse flow prevention bidirectional inverter 8, so that the system is in a grid-connected mode. In this mode, when the sunlight is sufficient and the energy produced by the photovoltaic module 1 is both sufficient to charge the accumulator 4 and exceeds the energy consumed by the loads (dc and ac), the remaining energy is transmitted to the public network 14; when sunlight is common, the energy generated by the photovoltaic module 1 is sufficient for charging the storage battery 4, but is insufficient for the energy consumed by the load, the insufficient energy can be provided by the public network 14; when the sunlight is insufficient or even insufficient, the energy generated by the photovoltaic module 1 cannot meet the charging requirement of the storage battery 4, the public network 14 supplies power to the load and provides a part of energy for charging the storage battery through the bidirectional DC/DC converter 3; when sunlight is sufficient and the public network is temporarily forbidden to be connected with the grid, the anti-reflux switch on the DC/AC anti-reflux bidirectional inverter 8 can be disconnected, the energy generated by the photovoltaic module 1 can be used for charging the storage battery 4 and exceeds the energy consumed by the load, the DC/AC anti-reflux bidirectional inverter 8 runs in a limited power mode, and the phenomenon that voltage fluctuation of the public network is overlarge is avoided. When the power grid is powered off, the first switch 13 is switched off, the system processes an off-grid mode, and the photovoltaic module 1 and the storage battery 4 jointly or independently supply power to the load.

When the public power grid fails and stops supplying power, the system can be converted into an off-grid mode to independently operate and still supply power to a local load, and continuous work of important equipment is guaranteed, so that the reliability and the convenience of power supply are higher, meanwhile, the system and the public power grid are mutually supported (grid-connected mode), so that the capacity of a storage battery can be effectively reduced according to the actual power grid condition and the power consumption of the important load, the system construction cost can be greatly reduced, multiple operation working conditions can be realized in the grid-connected mode, the photovoltaic module is enabled to generate power to be fully utilized, the demand on the electric quantity of the public power grid is reduced, the demand of a user is met, and the benefit maximization of the user is realized.

A third switch 10 for controlling the power on/off of the 220V ac bus 12 to the ac load 11 is provided between the ac load 11 and the 220V ac bus 12 of the system. Therefore, when the public network is powered off and the electric quantity of the storage battery and the electric quantity of the photovoltaic module are insufficient, the requirement of the direct current load can be met independently.

The first switch 13, the second switch 9 and the third switch 10 can adopt one of a relay, a contactor and a power switch tube, and the first switch 13, the second switch 9 and the third switch 10 of the system adopt relays so as to be convenient to control. When the relay is adopted, the control coil of the relay can be connected to the output end of the DC/DC power supply converter.

Preferably, the DC/DC power converter 6 is provided with a plurality of output terminals with different output voltages to meet the requirements of different DC loads. Usually, 5V output, 12V output and 20V output are required.

Claims

1. The utility model provides a and domestic energy storage system of integration of leaving net, includes photovoltaic module (1), battery (4), its characterized in that: the system also comprises a unidirectional DC/DC converter (2), a bidirectional DC/DC converter (3), a DC/DC power converter (6), a DC/AC anti-reflux bidirectional inverter (8), a first switch (13), a second switch (9), a direct current load (5) and an alternating current load (11);

the photovoltaic module (1) is electrically connected with the input end of the unidirectional DC/DC converter (2), the output end of the unidirectional DC/DC converter (2) is electrically connected with the direct current end of the DC/AC anti-reflux bidirectional inverter (8) through a direct current bus (7), the alternating current end of the DC/AC anti-reflux bidirectional inverter (8) is electrically connected with one end of the second switch (9), the other end of the second switch (9) is electrically connected with one end of the first switch (13) through a 220V alternating current bus (12), and the other end of the first switch (13) is electrically connected to a public network (14);

one end of the bidirectional DC/DC converter (3) is connected with the input end of the DC/DC power converter (6) in parallel on the direct current bus (7), the direct current load (5) is electrically connected with the output end of the DC/DC power converter (6), the storage battery (4) is electrically connected with the other end of the bidirectional DC/DC converter (3), and the alternating current load (11) is connected with the 220V alternating current bus (12) in parallel.

2. The grid-connected and off-grid integrated household energy storage system of claim 1, wherein: the alternating current load circuit further comprises a third switch (10) arranged between the alternating current load (11) and the 220V alternating current bus (12) to control the 220V alternating current bus (12) to be powered on or powered off to the alternating current load (11).

3. The grid-connected and off-grid integrated household energy storage system of claim 2, wherein: the first switch (13), the second switch (9) and the third switch (10) are all relays.

4. The grid-connected and off-grid integrated household energy storage system of claim 1, wherein: the DC/DC power converter (6) is provided with a plurality of output ends with different output voltages.

5. The grid-connected and off-grid integrated household energy storage system of claim 4, wherein: the output end of the DC/DC power supply converter (6) comprises a 5V output end, a 12V output end and a 20V output end.