A fast charging and grid connection device based on energy storage power supply and its working method

Abstract

The present invention discloses a fast charging and grid-connection device based on an energy storage power supply and a working method thereof. Each of the energy storage power supplies is connected via an electric control switch and a disconnecting grid-connection connector, and each of the energy storage power supplies, each electric control switch and the disconnecting grid-connection connector are connected to an external power supply; multiple energy storage power supplies are arranged in parallel, and multiple electric control switches are arranged in parallel. The present invention is used to solve the problems of expensive photovoltaic charging, complex PD charging structure, low vehicle charging power, and low DC charging efficiency.

Description

Technical Field

[0001] The present invention belongs to the field of electronic applications and specifically relates to a fast charging and grid-connecting device based on an energy storage power supply and a working method thereof. Background Art

[0002] In the new energy industry, more and more high-power energy storage products are coming out. Energy storage products are very convenient for peripheral products and can effectively power mobile phones, tablets and even large household appliances. However, although the current technology has a variety of charging methods for energy storage devices themselves, it is difficult to have a fast, effective and safe charging method to solve the inconvenience caused by long charging time.

[0003] The existing technology has the following problems: 1: Photovoltaic charging, charging the battery cell through the solar panel connecting the controller, inverter to the BMS circuit, the charging power is directly determined by the number of solar panels, the more the number, the more expensive the price. 2: PD charging, charging the energy storage power supply through the Type C interface combined with the charging protocol, this solution currently has several disadvantages, first of all, the charging power is limited by the current technology, the maximum can only reach 100W, secondly, the Type C of the energy storage is generally used as the Out output, when it is also used as the In input, the circuit connection is more complicated than the OUT output only. 3: Car charger charging, charging the energy storage power supply through the car charger port, the disadvantage is low charging power. 4: DC charging, 220V is transformed to 24V / 12V and the energy storage is charged through the DC port, the charging efficiency is low, the charger needs to step down, so it is bulky and not easy to carry, and the charging is slow. Due to the limitations of current charging technology, battery cell charging rate, battery cell capacity, safety and other reasons, the charging speed is not very fast. Taking a 1KWH energy storage device as an example, it often takes 7 or 8 hours to fully charge using any of the above charging methods, which is very inconvenient for providing convenient energy storage equipment. Summary of the invention

[0004] The present invention provides a fast charging and grid connection device based on an energy storage power supply and a working method thereof, which are used to solve the problems of expensive photovoltaic charging, complex PD charging structure, low vehicle charging power and low DC charging efficiency.

[0005] The present invention is achieved through the following technical solutions:

[0006] A fast charging and grid-connecting device based on an energy storage power supply, the fast charging and grid-connecting device comprising a plurality of energy storage power supplies, a plurality of electric control switches and a disconnecting grid-connecting connector, each of the energy storage power supplies is connected via an electric control switch and a disconnecting grid-connecting connector, each of the energy storage power supplies, each electric control switch and each disconnecting grid-connecting connector are connected to an external grid power supply;

[0007] Multiple energy storage power supplies are arranged in parallel, and multiple electric control switches are arranged in parallel;

[0008] The disconnecting grid-connected connector includes a connector power supply, an AFE module, an MCU module, a communication module, a charging protection switch, a discharging protection switch, a buck rectifier module, a relay switch I and a relay switch II. The connector power supply is connected to the AFE module, the AFE module is respectively connected to the MCU module and the discharging protection switch, the discharging protection switch is connected to the charging protection switch, the charging protection switch is connected to the buck rectifier module, the buck rectifier module is respectively connected to the relay switch I and the relay switch II, and the MCU module is connected to the communication module.

[0009] Furthermore, one end of the connector power supply is connected to the B+ end, the relay switch I and one end of the charging overcurrent fuse, an NTC detection head is arranged between the connector power supply, the other end of the charging overcurrent fuse is connected to one end of the switch M2 and the negative electrode of the charging diode, and the other end of the switch M2 and the positive electrode of the charging diode are both connected to the first end of the buck rectifier module;

[0010] The second end of the step-down rectifier module is also connected to the relay switch I and the external power bus through an overcurrent fuse, the third end of the step-down rectifier module is connected to the charging protection switch, the charging protection switch is connected to the discharging protection switch, the discharging protection switch is connected to the current sensing resistor, and the current sensing resistor is connected to the other end of the connector power supply;

[0011] The fourth end of the step-down rectifier module is connected to the internal network voltage and current detection of the MCU module and the relay switch II respectively, and the relay switch II is connected to the external network power bus;

[0012] The information interaction of the MCU module is connected to the communication module, the external network voltage and current detection of the MCU module is connected to the external network power bus, the state parameter information control and conversion of the MCU module is connected to the ⅡC communication module of the AFE module, the overcurrent protection of the AFE module controls the charging protection switch and the discharging protection switch, the current detection module of the AFE module detects the current signal of the current detection resistor, and the voltage and temperature acquisition module of the AFE module detects the temperature / voltage signal of the NTC detection head;

[0013] The MCU module controls the relay switch I and the relay switch II to connect and disconnect the external power grid AC and the internal power grid AC.

[0014] Furthermore, the relay switch I includes relay I, terminal 5 of the relay I is respectively connected to the working voltage VCC and the cathode of the diode D1, terminal 4 of the relay I is respectively connected to the anode of the diode D1 and terminal 3 of the transistor Q1, terminal 2 of the transistor Q1 is grounded, terminal 1 of the transistor Q1 is connected in series with a resistor R and a diode D2 and then connected to the MCU module and relay switch II, terminal 3 of the relay I is connected to a single-pole double-throw switch K1, terminal 2 of the single-pole double-throw switch K1 is connected to the MCU module and the external power bus, and terminal 1 of the single-pole double-throw switch K1 is connected to an overcurrent fuse.

[0015] Furthermore, the relay switch I has the same structure as the relay switch II, the terminal 1 of the single-pole double-throw switch K2 of the relay switch II is connected to the fourth terminal of the step-down rectifier module, and the terminal 2 of the single-pole double-throw switch K2 is connected to the external power bus; the cathode of the diode D4 of the relay switch II is connected to the cathode of the diode D2 of the relay switch I.

[0016] A working method of a fast charging and grid connection device based on an energy storage power supply, the working method comprising the following steps:

[0017] Step 1: Connect the mains power supply and the home grid directly to the AC output port of the energy storage power supply through the disconnect and grid-connector;

[0018] Step 2: The electric energy from the AC output port of the energy storage power supply in step 1 is reversely stepped down by the inverter to charge the AC, and then charged by the energy storage power supply after detection and rectification by the inverter;

[0019] Step 3: When the city power fails, the energy storage power source that has been charged in step 2 turns on the AC output to power household appliances.

[0020] Furthermore, the step 1 is specifically that the two-way relay switch of the disconnecting grid-connector is connected to the AC power grid to separate the AC power grid into two parts, an external power grid and an internal power grid;

[0021] When the energy storage power supply joins the home grid, it will register with the disconnected grid-connected connector through the communication network. When the registration ACK signal fed back by the disconnected grid-connected connector is received, it means that the communication has been connected. The energy storage power supply needs to communicate with the disconnected grid-connected connector regularly to confirm that the energy storage power supply is still in the network.

[0022] Furthermore, step 2 is specifically as follows: when the disconnected grid-connected connector detects the presence of AC power in the external network, a configuration command is sent to the energy storage power supply through the communication network. At this time, the energy storage power supply no longer needs to detect the grid-connected network, and directly isolates the AC output and converts it into AC charging input. The disconnected grid-connected connector will detect whether there is still AC voltage in the internal network. Only when there is no voltage in the internal grid, the disconnected grid-connected connector opens the connection switch. At this time, the mains power enters the internal grid, passes through the AC port to the inverter, and is frequency-detected by the inverter, and then the energy storage power supply is charged after detection and rectification.

[0023] Furthermore, step 3 is specifically as follows: when the mains power is cut off, the grid-connected connector detects that there is no mains power in the external network, and the disconnected grid connector disconnects the internal grid from the external grid through the switch control module, communicates with the energy storage device through the communication module, and configures the energy storage power supply to turn off the AC input and turn on the AC output. After receiving the configuration command of the disconnected grid-connected connector, the energy storage device turns on the AC output. At this time, the internal grid has AC power supply and can power household appliances.

[0024] The beneficial effects of the present invention are:

[0025] The present invention can easily achieve 80% energy charging in one hour. This method can not only achieve fast charging, but also connect multiple energy storage power sources to the grid to increase capacity and power to achieve the purpose of household energy storage.

[0026] The device of the present invention stores energy when the electricity price is cheap in an area with stepped electricity prices, and disconnects from the external power grid when the electricity price is expensive, and uses the energy storage power supply for power supply.

[0027] The present invention has a smaller volume, can be fully charged in a very short time, and can truly and easily be carried for outdoor use when in stand-alone mode.

[0028] The present invention connects multiple machines to the grid to form a household energy storage device, which achieves the beneficial effects of storing electricity when there is electricity and supplying electricity when there is no electricity. Secondly, it is easy to install. It only needs to add a disconnecting and connecting-to-grid connector to the mains access port, cooperate with the energy storage device, and easily connect to the grid for use. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Attached Figure 1 It is a structural schematic diagram of the present invention.

[0030] Attached Figure 2 It is a flow chart of the method of the present invention.

[0031] Attached Figure 3 It is a schematic structural diagram of the disconnecting and connecting grid connector of the present invention.

[0032] Attached Figure 4 It is a signal schematic diagram of the disconnecting grid-connected connector and the energy storage power supply of the present invention. DETAILED DESCRIPTION

[0033] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] A fast charging and grid-connecting device based on an energy storage power supply, the fast charging and grid-connecting device comprising a plurality of energy storage power supplies, a plurality of electric control switches and a disconnecting grid-connecting connector, each of the energy storage power supplies is connected via an electric control switch and a disconnecting grid-connecting connector, each of the energy storage power supplies, each electric control switch and each disconnecting grid-connecting connector are connected to an external grid power supply;

[0035] Multiple energy storage power supplies are arranged in parallel, and multiple electric control switches are arranged in parallel;

[0036] The disconnecting grid-connected connector includes a connector power supply, an AFE module, an MCU module, a communication module, a charging protection switch, a discharging protection switch, a buck rectifier module, a relay switch I and a relay switch II. The connector power supply is connected to the AFE module, the AFE module is respectively connected to the MCU module and the discharging protection switch, the discharging protection switch is connected to the charging protection switch, the charging protection switch is connected to the buck rectifier module, the buck rectifier module is respectively connected to the relay switch I and the relay switch II, and the MCU module is connected to the communication module.

[0037] The AFE module is responsible for collecting the voltage and temperature of the battery cell, current detection and other parameters, and exchanges information with the MCU through the IIC communication module. It can provide overvoltage protection, overcurrent protection, undervoltage protection, short circuit protection, temperature protection, etc. for the connector. Once the above protection occurs, the AFE module will control the protection charge and discharge switch to disconnect the internal switch of the connector to play a protective role. The LDO module is responsible for providing a stable power supply to the MCU module. The communication module is responsible for the registration and communication between the MCU and the energy storage power supply (including sending heartbeat data, real-time data, and command data, etc. The heartbeat data is sent every once in a while to ensure that the MCU confirms that the energy storage power supply is still in the parallel power network).

[0038] Furthermore, one end of the connector power supply is connected to the B+ end, the relay switch I and one end of the charging overcurrent fuse, an NTC detection head is arranged between the connector power supply, the other end of the charging overcurrent fuse is connected to one end of the switch M2 and the negative electrode of the charging diode, and the other end of the switch M2 and the positive electrode of the charging diode are both connected to the first end of the buck rectifier module;

[0039] The second end of the step-down rectifier module is also connected to the relay switch I and the external power bus through an overcurrent fuse, the third end of the step-down rectifier module is connected to the charging protection switch, the charging protection switch is connected to the discharging protection switch, the discharging protection switch is connected to the current sensing resistor, and the current sensing resistor is connected to the other end of the connector power supply;

[0040] The fourth end of the step-down rectifier module is connected to the internal network voltage and current detection of the MCU module and the relay switch II respectively, and the relay switch II is connected to the external network power bus;

[0041] The information interaction of the MCU module is connected to the communication module, the external network voltage and current detection of the MCU module is connected to the external network power bus, the state parameter information control and conversion of the MCU module is connected to the ⅡC communication module of the AFE module, the overcurrent protection of the AFE module controls the charging protection switch and the discharging protection switch, the current detection module of the AFE module detects the current signal of the current detection resistor, and the voltage and temperature acquisition module of the AFE module detects the temperature / voltage signal of the NTC detection head;

[0042] The MCU module controls the relay switch I and the relay switch II to connect and disconnect the external power grid AC and the internal power grid AC.

[0043] Furthermore, the relay switch I includes relay I, terminal 5 of the relay I is respectively connected to the working voltage VCC and the cathode of the diode D1, terminal 4 of the relay I is respectively connected to the anode of the diode D1 and terminal 3 of the transistor Q1, terminal 2 of the transistor Q1 is grounded, terminal 1 of the transistor Q1 is connected in series with a resistor R and a diode D2 and then connected to the MCU module and relay switch II, terminal 3 of the relay I is connected to a single-pole double-throw switch K1, terminal 2 of the single-pole double-throw switch K1 is connected to the MCU module and the external power bus, and terminal 1 of the single-pole double-throw switch K1 is connected to an overcurrent fuse.

[0044] Furthermore, the relay switch I has the same structure as the relay switch II, the terminal 1 of the single-pole double-throw switch K2 of the relay switch II is connected to the fourth terminal of the step-down rectifier module, and the terminal 2 of the single-pole double-throw switch K2 is connected to the external power bus; the cathode of the diode D4 of the relay switch II is connected to the cathode of the diode D2 of the relay switch I.

[0045] A working method of a fast charging and grid connection device based on an energy storage power supply, the working method comprising the following steps:

[0046] Step 1: Connect the mains power supply and the home grid directly to the AC output port of the energy storage power supply through the disconnect and grid-connector;

[0047] Step 2: The electric energy from the AC output port of the energy storage power supply in step 1 is reversely stepped down by the inverter to charge the AC, and then charged by the energy storage power supply after detection and rectification by the inverter;

[0048] Step 3: When the city power fails, the energy storage power source that has been charged in step 2 turns on the AC output to power household appliances.

[0049] The working principle is as follows: the MCU module detects the voltage and current of the external power grid through the internal voltage detection circuit to determine whether there is mains power in the external power grid. When it is detected that there is no mains power, the MCU will send configuration information to the energy storage power source registered to the disconnected grid connector through the communication module (WIFI / 4G / NB / Bluetooth / ZigBEE / serial port, etc.), informing that the external power grid has been disconnected, and at the same time control the relay to disconnect from the external power grid. At this time, the (home) internal power grid is completely disconnected and isolated from the external power grid. Each energy storage device in the grid will turn on the AC output to supply power to the internal power network, which can provide temporary power supply to household appliances. When the voltage detection circuit of the MCU detects that there is AC power in the external power grid and it exists for a period of time (the detection time is to ensure the stable existence of external power), the MCU sends a configuration signal to the energy storage device through the communication module to shut down the AC output of the energy storage power supply. After detecting that there is no voltage or current in the internal power grid, the MCU controls the relay to open the connection between the external power grid and the internal power grid. At this time, the internal power grid is connected to the external power network, and the AC power passes through the AC end of the energy storage power supply, the inverter, and the charging control circuit to the battery cell module of the energy storage power supply for fast charging.

[0050] Furthermore, the step 1 is specifically that the two-way relay switch of the disconnecting grid-connector is connected to the AC power grid to separate the AC power grid into two parts, an external power grid and an internal power grid;

[0051] When the energy storage power supply joins the home grid, it will register with the disconnected grid-connected connector through the communication network. When the registration ACK signal fed back by the disconnected grid-connected connector is received, it means that the communication has been connected. The energy storage power supply needs to communicate with the disconnected grid-connected connector regularly to confirm that the energy storage power supply is still in the network.

[0052] Furthermore, step 2 is specifically as follows: when the disconnected grid-connected connector detects the presence of AC power in the external network, a configuration command is sent to the energy storage power supply through the communication network. At this time, the energy storage power supply no longer needs to detect the grid-connected network, and directly isolates the AC output and converts it into AC charging input. The disconnected grid-connected connector will detect whether there is still AC voltage in the internal network. Only when there is no voltage in the internal grid, the disconnected grid-connected connector opens the connection switch. At this time, the mains power enters the internal grid, passes through the AC port to the inverter, and is frequency-detected by the inverter, and then the energy storage power supply is charged after detection and rectification.

[0053] Furthermore, the step 3 is specifically as follows: when the city power is cut off, the grid-connected connector detects that there is no city power in the external network, and the disconnected network connector disconnects the internal power grid from the external power grid through the switch control module, communicates with the energy storage device through the communication module (the internal power grid currently has no power and needs to be powered, that is, sends a configuration command), configures the energy storage power supply to turn off the AC input and turn on the AC output, and after receiving the configuration command of the disconnected grid-connected connector, the energy storage device turns on the AC output. At this time, the internal power grid has AC power supply and can power household appliances.

[0054] Due to the limitations of current charging technology, battery charging rate, battery capacity, safety and other reasons, the charging speed is not very fast. Taking a 1KWH energy storage device as an example, it often takes 7 or 8 hours to fully charge using any of the above charging methods, which is very inconvenient for providing convenient energy storage devices. Through practice, we propose a way to safely and efficiently realize fast charging of energy storage devices through grid connection.

[0055] Energy storage power supplies can be carried and used alone, and are suitable for outdoor use. When not in use, you only need to connect the AC port to the power grid to achieve fast charging without the need for an additional connection adapter. More than 90% of the time, energy storage power supplies are used at home, and only 10% are used outside. Such long-term storage will inevitably cause power shortages due to forgetting to charge or the power consumption of the energy storage itself. After connecting to the disconnection and power-sharing network through the AC port, the energy storage power supply can be quickly charged and discharged, effectively solving this problem. Ensure that there is enough electricity to use every time you go out, and the energy storage power supply can also be effectively used at home. In addition, in areas where power is extremely scarce, the energy storage power supply can be stored when there is city power. When there is no city power, the stored power can be sold to the country through the external power grid, or used for personal use.

Claims

1. A fast charging and grid connection device based on energy storage power supply, characterized in that: The fast charging and grid-connection device comprises a plurality of energy storage power supplies, a plurality of electric control switches and disconnecting grid-connection connectors, each of the energy storage power supplies is connected via an electric control switch and a disconnecting grid-connection connector, and each of the energy storage power supplies, each electric control switch and each disconnecting grid-connection connector are connected to an external grid power supply; Multiple energy storage power supplies are arranged in parallel, and multiple electric control switches are arranged in parallel; The disconnecting and grid-connected connector includes a connector power supply, an AFE module, an MCU module, a communication module, a charging protection switch, a discharge protection switch, a buck rectifier module, a relay switch I and a relay switch II. The connector power supply is connected to the AFE module, the AFE module is respectively connected to the MCU module and the discharge protection switch, the discharge protection switch is connected to the charging protection switch, the charging protection switch is connected to the buck rectifier module, the buck rectifier module is respectively connected to the relay switch I and the relay switch II, and the MCU module is connected to the communication module; One end of the connector power supply is connected to the B+ end, the relay switch I and one end of the charging overcurrent fuse, an NTC detection head is arranged between the connector power supplies, the other end of the charging overcurrent fuse is connected to one end of the switch M2 and the negative electrode of the charging diode, and the other end of the switch M2 and the positive electrode of the charging diode are both connected to the first end of the buck rectifier module; the second end of the buck rectifier module is also connected to the relay switch I and the external network power bus through the overcurrent fuse, the third end of the buck rectifier module is connected to the charging protection switch, the charging protection switch is connected to the discharge protection switch, the discharge protection switch is connected to the current sensing resistor, and the current sensing resistor is connected to the other end of the connector power supply; The fourth end of the step-down rectifier module is connected to the internal network voltage and current detection of the MCU module and the relay switch II respectively, and the relay switch II is connected to the external network power bus; The information interaction of the MCU module is connected to the communication module, the external network voltage and current detection of the MCU module is connected to the external network power bus, the state parameter information control and conversion of the MCU module is connected to the ⅡC communication module of the AFE module, the overcurrent protection of the AFE module controls the charging protection switch and the discharging protection switch, the current detection module of the AFE module detects the current signal of the current detection resistor, and the voltage and temperature acquisition module of the AFE module detects the temperature / voltage signal of the NTC detection head; The MCU module controls the relay switch I and the relay switch II to connect and disconnect the external power grid AC and the internal power grid AC.

2. A fast charging and grid connection device based on energy storage power supply according to claim 1, characterized in that: The relay switch I includes relay I, terminal 5 of the relay I is respectively connected to the working voltage VCC and the cathode of the diode D1, terminal 4 of the relay I is respectively connected to the anode of the diode D1 and terminal 3 of the transistor Q1, terminal 2 of the transistor Q1 is grounded, terminal 1 of the transistor Q1 is connected in series with a resistor R and a diode D2 and then connected to the MCU module and the relay switch II, terminal 3 of the relay I is connected to a single-pole double-throw switch K1, terminal 2 of the single-pole double-throw switch K1 is connected to the MCU module and the external power bus, and terminal 1 of the single-pole double-throw switch K1 is connected to an overcurrent fuse.

3. A fast charging and grid connection device based on energy storage power supply according to claim 2, characterized in that: The relay switch I has the same structure as the relay switch II. Terminal 1 of the single-pole double-throw switch K2 of the relay switch II is connected to the fourth terminal of the step-down rectifier module, and terminal 2 of the single-pole double-throw switch K2 is connected to the external power bus; the cathode of the diode D4 of the relay switch II is connected to the cathode of the diode D2 of the relay switch I.

4. A working method of a fast charging and grid connection device based on an energy storage power supply according to claim 1 or 3, characterized in that: The working method comprises the following steps: Step 1: Connect the mains power supply and the home grid directly to the AC output port of the energy storage power supply through the disconnect and grid-connector; Step 2: The electric energy from the AC output port of the energy storage power supply in step 1 is reversely stepped down by the inverter to charge the AC, and then charged by the energy storage power supply after detection and rectification by the inverter; Step 3: When the city power fails, the energy storage power source that has been charged in step 2 turns on the AC output to power household appliances.

5. The working method of the fast charging and grid connection device based on energy storage power supply according to claim 4 is characterized in that: Specifically, the step 1 includes connecting two relay switches of the disconnecting and connecting grid connector to the AC power grid to separate the AC power grid into two parts: an external power grid and an internal power grid; When the energy storage power supply joins the home grid, it will register with the disconnected grid-connected connector through the communication network. When the registration ACK signal fed back by the disconnected grid-connected connector is received, it means that the communication has been connected. The energy storage power supply needs to communicate with the disconnected grid-connected connector regularly to confirm that the energy storage power supply is still in the network.

6. The working method of the fast charging and grid connection device based on energy storage power supply according to claim 4 is characterized in that: Specifically, step 2 is as follows: when the disconnected grid-connected connector detects the presence of AC power in the external network, a configuration command is sent to the energy storage power supply through the communication network. At this time, the energy storage power supply no longer needs to detect the grid-connected network, and directly isolates the AC output and converts it into AC charging input. The disconnected grid-connected connector detects whether there is still AC voltage in the internal network. Only when there is no voltage in the internal grid, the disconnected grid-connected connector opens the connection switch. At this time, the mains power enters the internal grid, passes through the AC port to the inverter, and is frequency-detected by the inverter, and then the energy storage power supply is charged after detection and rectification.

7. The working method of the fast charging and grid connection device based on energy storage power supply according to claim 4 is characterized in that: Specifically, step 3 is as follows: when the city power is cut off, the grid-connected connector detects that there is no city power in the external network, and the disconnected grid connector disconnects the internal grid from the external grid through the switch control module, communicates with the energy storage device through the communication module, and configures the energy storage power supply to turn off the AC input and turn on the AC output. After receiving the configuration command of the disconnected grid connector, the energy storage device turns on the AC output. At this time, the internal grid has AC power supply and can power household appliances.

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