CN111446755A - Capacity-expandable hot-plug type battery power supply system and control method - Google Patents

Abstract

The invention discloses an expandable hot-swappable battery power supply system and a control method, comprising an inverter box and at least one battery box; the inverter box includes an inverter module and a charging module, an AC output port and an AC input port; The battery box includes: a power port and a communication interface, the communication interface is used to build a distributed network of the battery box, and the battery box switches for power supply or charging through the distributed network; the technical scheme of the present invention separates the battery box from the inverter box, The data exchange and update are completed between the battery boxes by building a distributed network, and the switching of power supply or charging of the battery boxes can be completed independently without the help of other control devices or central processing units. Based on this distributed network, the battery box can also be realized. Therefore, the system of the present invention not only has good expansion and new performance, but also can achieve convenient, intelligent and efficient power supply, and can be widely used in the field of power storage technology.

Description

Scalable hot-swappable battery power supply system and control method

technical field

The invention relates to the technical field of power storage, in particular to an expandable hot-swappable battery power supply system and a control method.

Background technique

With the problem of global climate change and the reduction of non-renewable energy, electric energy is widely respected as a clean and green energy. However, due to certain limitations, under some conditions and occasions, the alternating current cannot be directly delivered, and it needs to be obtained through the battery carrier and the direct current inversion to the alternating current. Lithium batteries are widely used in energy storage systems due to their high energy density, long service life, and no memory effect. Lithium batteries form battery packs in series and parallel mode, use battery management system (BMS) to manage battery packs, and cooperate with electronic circuits to form a power supply system, which can solve the problem of power supply in places where most electric energy cannot reach directly. It is aimed at construction sites. It is an AC power supply system developed for applications in places such as medical centers, communication base stations and natural disasters.

However, the current lithium battery energy storage devices or systems still have the following technical problems:

1) The scalability and sustainable performance are poor, which directly leads to the fact that the electric energy provided by the entire energy storage device is insufficient to support long-term operation.

2) Hot-swap operation is not supported, and the choice of which battery pack to discharge needs to be judged by the central processing unit, resulting in low efficiency and poor reliability.

3) The battery pack is powered in parallel, so if the voltage of the battery pack is not consistent during use, it is easy to generate a circulating current.

cause damage to the battery.

SUMMARY OF THE INVENTION

In order to solve one of the above technical problems, the purpose of the present invention is to provide an expandable hot-swappable battery power supply system and a control method with convenient operation and high safety of the battery box.

The technical scheme adopted by the present invention is:

An expandable hot-swappable battery power supply system includes an inverter box and at least one battery box; the inverter box includes:

Inverter module for converting direct current into alternating current;

A charging module for converting alternating current into direct current;

AC output port for inputting AC power;

AC input port for outputting AC power;

The battery box includes:

Power port for connecting the battery box to the inverter box;

The communication interface is used to build a distributed network of battery boxes, and switch the battery boxes for power supply or charging through the distributed network;

Wherein, the inverter module is connected with the AC output port; the charging module is connected with the AC input port; the battery box is connected with the inverter box through the power port.

Further, the inverter box also includes:

The first bus bar and the second bus bar are used to connect to the power interface of at least one battery box, and receive the electric energy of the battery box or provide the electric energy for the battery box;

an inverter start switch, used for starting or closing the inverter module;

The battery box is respectively connected with one end of the first busbar and one end of the second busbar; the other end of the first busbar is respectively connected with the input end of the inverter module and the output end of the charging module; the other end of the second busbar is respectively It is connected with the input end of the inverter module and the output end of the charging module; the output end of the inverter module is connected with the AC output port, the start switch signal receiving end of the inverter module is connected with the inverter start switch; the input end of the charging module is connected with the Connect the AC input port described above.

Further, the battery box also includes:

battery packs to store or release electrical energy;

BMS module for monitoring and acquiring the voltage and temperature of the battery;

CPU processor for receiving signals and sending control signals;

DC/DC converter for outputting a fixed voltage;

a fan for cooling the battery box;

a main power switch for turning on or off the power input, power output and communication of the battery box;

an output control switch; used to turn on or off the power output of the battery box;

The output control switch is connected to the output control end of the CPU processor; the communication interface of the battery box is connected to the first communication port of the CPU processor; the second communication port of the CPU processor is connected to the BMS module The control port of the CPU processor is connected to the DC/DC converter; the information collection port of the BMS module is connected to the battery pack; the positive poles of the battery pack are respectively connected to the first terminal of the DC/DC converter An input terminal is connected to the positive pole of the power port; the negative pole of the battery pack is connected to the second input terminal of the DC/DC converter and the negative pole of the power supply port, respectively. The fan of the DC/DC converter is connected to The control port is connected to the fan, the main power control port of the DC/DC converter is connected to the main power switch, and the interlock signal port of the DC/DC converter is connected to the power port.

Further, the battery box also includes: an anti-backflow module and a main relay for preventing current from backflow;

The input end of the anti-backflow module is connected to the positive pole of the battery pack; the output end of the anti-backflow module is connected to the positive pole of the main relay, and the first control port of the anti-backflow module is connected to the CPU processor , the second control port of the anti-backflow module is connected to the DC/DC converter, the pre-charge port of the anti-backflow module is connected to the positive pole of the power supply port; the negative pole of the main relay is connected to the power supply port The positive pole of the main relay is connected, and both ends of the coil of the main relay are connected to the control port of the main controller of the DC/DC converter.

Further, the battery box further includes a fuse for protecting the circuit when the circuit is abnormal;

One end of the fuse is connected to the input end of the anti-backflow module, and the other end of the fuse is connected to the positive electrode of the battery pack.

Further, the battery box further includes a display device, and the display device is connected to the CPU processor.

Further, the battery box is connected and communicated with the battery box through CAN.

Further, the bottom of the battery box is provided with a pulley.

Another technical scheme adopted by the present invention is:

Get the number, charge and temperature of the currently connected battery boxes;

Select the battery box to supply power according to the charge amount and temperature;

Update the number, charge and temperature of the battery boxes through a distributed network;

Switch to the battery box for power supply based on the number, charge and temperature of the updated battery box.

Further, the step of updating the number, charge and temperature of the battery boxes through a distributed network specifically includes:

The battery box forms a distributed network through CAN communication;

Obtain the charge and temperature of the battery box itself;

Update the charge and temperature of battery boxes in the distributed network, and obtain the number of battery boxes.

The beneficial effects of the present invention are: the technical solution of the present invention separates the battery box and the inverter box, and the data exchange and update are completed between the battery boxes by constructing a distributed network, without the help of other control devices or central processing units. In this way, the switching of power supply or charging of the battery box can be completed independently, and the hot-plugging operation of the battery box can also be realized based on the distributed network. Therefore, the system of the present invention not only has good expansion performance, but also can achieve convenient, intelligent and efficient power supply.

Description of drawings

1 is a schematic diagram of the connection relationship between the battery box and the inverter box of the expandable hot-swap battery power supply system of the present invention;

2 is a schematic diagram of the circuit inside the inverter box of the expandable hot-swap battery power supply system of the present invention;

3 is a schematic diagram of the circuit inside the battery box of the expandable hot-swap battery power supply system of the present invention;

4 is a layout diagram of a battery box panel of an expandable hot-swap battery power supply system of the present invention;

FIG. 5 is a flow chart of the steps of a control method for power supply by an expandable hot-swap battery power supply according to the present invention.

Reference numerals: 101, main power switch; 102, power port; 103, fan; 104, output control switch; 105, display device; 106, communication interface; 201, first bus bar; 202, second bus bar.

Detailed ways

The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

The present invention mainly includes two parts: an inverter box and a battery box. As shown in FIG. 1 , four battery boxes and one inverter box are selected as specific embodiments for description in this specification. The four battery boxes are respectively connected to the third part of the inverter box. A battery box interface CH1, a second battery box interface CH2, a third battery box interface CH3 and a fourth battery box interface CH4.

As shown in Figure 2, the inverter module in the inverter box is used to convert the DC power provided by the power box into AC power for each electrical appliance; the charging module is used to convert the AC power into DC power when charging the battery box; four The battery box is connected to the battery box interface of the inverter box through the power port, and is connected to the input end of the inverter module and the output end of the charging module through the first bus bar 201 and the second bus bar 202 respectively. The first and second bus bars The positive and negative power supply boxes used to collect four battery boxes are used to connect the power interface of at least one battery box, receive the electric energy of the battery box or provide electric energy for the battery box, and play a relay role; the output end of the inverter module is connected to To the AC output port, it is used to convert the DC power stored in the battery box into AC power to supply power for electrical appliances; the inlet and outlet of the charging module are connected to the AC input port, which is used to convert the external AC power to the DC power of the battery pack to provide power when charging the battery. In addition, the inverter box is also provided with an inverter start switch, which is connected to the switch signal receiving end of the inverter module to control whether the inverter module works, that is, whether the battery box provides power. The AC output port and the AC input port are mainly used for the current output and input of the battery box.

As shown in Figure 3, the interior of the battery box mainly includes a battery pack, which is used to store or release electrical energy; the positive and negative poles of the battery pack are connected to the power port to provide DC power to the inverter box or receive DC power from the inverter box for storage; BMS ( A battery management system) module, one end is connected to the battery pack, and the other end (communication end) is connected to the second communication end of the CPU processor, used to monitor and obtain the voltage and temperature information of the battery pack, when the battery pack appears voltage and/or When the temperature is abnormal, the abnormal signal will be transmitted to the CPU processor, and the CPU processor will issue an abnormal alarm; the CPU module, the core of the battery box, is used to receive signals from other modules and issue control signals, and also plays a role in coordinating with the battery. The function of maintaining the communication connection of other battery boxes makes the whole battery box have the functions of overload protection, over-temperature protection, under-voltage protection, over-voltage protection and short-circuit protection; the first communication port of the CPU processor is connected with the communication interface of the battery box, The second communication port is connected to the BMS module, the control port of the CPU processor is connected to the DC/DC converter, and the output control end of the CPU processor is connected to an output control switch, which can control whether the power box supplies power to the outside; the battery box It also includes a DC/DC converter. When the battery box is charged, the voltage of the external power supply is converted into the limited voltage of the battery pack; when the battery box is discharged, the power supply voltage of the battery pack is converted into the corresponding inverter module of the inverter box. Fixed voltage received; the input of this converter is connected to the positive and negative poles of the battery pack. A fan is connected to the fan control port of the DC/DC converter for cooling the entire battery box; the main power control port of the converter is connected to the main power switch, which is used to control whether the entire battery box is Work (power supply function and communication function); the interlock signal port of the DC/DC converter is connected to the power port to receive the current signal from the inverter connected to the battery box, so that the battery box enters the connected state or the waiting state. In addition, the battery box is also provided with an output control switch for individually controlling whether the battery box supplies power. The output control switch is directly connected with the CPU processor in the battery box, and the power supply is turned on or off by sending a control signal (instruction) from the CPU processor.

The battery box in this embodiment further includes an anti-backflow module, a main relay, a fuse and a display device; the two control ports of the anti-backflow are respectively connected to the DC/DC converter and the CPU processor, and the output terminal is connected to the positive pole of the main relay , the input terminal is connected to a fuse and then connected to the positive pole of the battery pack. The fuse is used to blow the fuse when the circuit generates an abnormal (exceeding the specified value) current, which plays the role of protecting the circuit; the negative pole of the main relay is connected to The positive pole of the power port of the battery box, its coil is connected to the control port of the main controller of the DC/DC converter, and the main relay is used to cut off the circuit according to the signal of the control port of the main controller when the battery box is backflowed, and it also protects The function of the battery box circuit; the precharge port of the anti-backflow module is also connected to the power port, which is also used to avoid the backflow phenomenon caused by other battery boxes supplying power to the battery box when the power supply is stopped; The display device is connected to the signal output port of the CPU processor to display the working state of the battery box and the state of charge SOC.

As an embodiment, a distributed communication system constructed by CAN is used between the battery boxes and the battery boxes to construct a distributed network to complete the information exchange between the battery boxes and the battery boxes. CAN communication can make the distributed network structure The battery boxes of different nodes receive the same data at the same time, and the communication is more real-time. The redundant structure formed can improve the reliability and flexibility of the system. Compared with RS485 communication, it can only form master-slave and master station polling. The communication method is more practical.

As an embodiment, as shown in FIG. 4 , the bottom of the battery box is provided with pulleys, so that the battery box is easy to carry and transport, and at the same time, a main power switch 101, a power port 102 and a fan are arranged on one side (back) of the battery box 103; An output control switch 104, a display device 105 and two communication interfaces 106 are provided on the other side of the battery box.

As shown in FIG. 5 , this example also provides an embodiment of a control method for an expandable hot-swap battery power supply, the steps of which include:

Get the number, charge and temperature of the currently connected battery boxes;

Select the battery box to supply power according to the charge amount and temperature;

Update the number, charge and temperature of the battery boxes through a distributed network;

Switches to one of the other battery boxes for power supply based on the number, charge and temperature of the updated battery box.

Further, as an optional implementation:

The step of updating the quantity, charge and temperature of the battery boxes through a distributed network specifically includes: the battery boxes form a distributed network through CAN communication; obtain the charge and temperature of the battery box itself; The distributed network updates the charge and temperature of other battery boxes in the network, and obtains the number of battery boxes.

The operation process and corresponding technical effect of this method embodiment will be described in detail in conjunction with the embodiment of the system:

The embodiment of this method also selects a battery power supply system composed of four battery boxes and one inverter box. The four battery boxes are connected to the inverter box at the same time, and the battery management system (BMS) of the battery box itself adopts the battery voltage and current integration method. (Ampere-hour integration method), calculate the state of charge (SOC) and temperature of its own battery, and then through CAN communication, the CPU of each battery box system obtains the number of connected battery boxes and the state of charge (SOC) of each battery box. ) and temperature, so as to select the battery box with the highest SOC and the temperature within the optimal working range to supply power, and select the battery box as the main control unit. The number of battery boxes, SOC and temperature, automatically switch to the battery box with the highest SOC and the temperature within the optimal working range to continue to supply power, and the exhausted battery box exits and can be replaced.

When the battery box is exhausted, you can unplug the wiring, replace it with a new battery box, wait for the system connection command, and continue to supply power. During the process of plugging and unplugging the battery box, the inverter can still continue to work and provide AC power to achieve continuous and uninterrupted power supply. . The main control unit of the battery box will periodically communicate with other connected battery boxes through CAN, update the number of connections and the SOC and temperature of other battery boxes, to ensure continuous power supply and necessary switching operations, even if the SOC is high when the battery box is just connected, because Access is late, so it won't switch right away. The charging of the battery pack is also carried out independently, and does not need to be calculated and processed by the central processing unit. The entire judgment network is jointly determined through a distributed network, which is more reliable and accurate. Even if a battery box fails, the system will not stop working or cause a safety accident.

The system can also be operated manually. The operator controls the switch through the key output on the spot, and selects a battery box with sufficient power to supply power, so that the other battery boxes are in a waiting state and can be disconnected.

The realization of the hot-swap function in the embodiment mainly relies on the independence of the hardware systems of the battery boxes, plus real-time communication with each other. For example, the battery boxes A and B are connected to the inverter box, the battery box A is in the working state, and the battery box B is in the In the idle state, if you want to disconnect the battery box B and connect the battery box C to the inverter box, you need to press the connector lock switch of the battery box B connected to the inverter box, unplug the connector, and then Connect the battery box C connector to the inverter box; if you want to disconnect the battery box A and connect the battery box C to the inverter box, you need to press the connector lock switch of the battery box A connected to the inverter box, the battery box Box A stops working immediately, just unplug the connector, the battery box exchanges and confirms the status data through the distributed network, immediately determines the battery box B and starts the working state, realizes uninterrupted power supply, and then connects the battery box C The inverter is connected to the inverter box. The battery box that runs out of power can be moved to a place with alternating current to charge and restore the power. The battery box has an interlocking protection function. If the battery box is supplying power, the indicator light on the battery box will be on for a long time. If the user unplugs the wiring, the battery box system will be disconnected and will notify other battery boxes to connect to the power supply.

To sum up, compared with the prior art, the present invention has the following advantages:

1) The present invention not only has strong development performance, supports hot swapping, but also ensures safe, convenient and efficient power supply;

2) The battery box of the present invention is connected to a distributed communication network through a communication interface, and the battery boxes cooperate to supply power, so the reliability of the system is higher and more accurate.

3) The structural design of the battery box of the present invention is lightweight, the bottom of the box is provided with wheels for easy handling and transportation, and the overall appearance is elegant.

The above-mentioned embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited by the above-mentioned embodiments, and any other changes, modifications, substitutions, combinations, The simplification should be equivalent replacement manners, which are all included in the protection scope of the present invention.

Claims (10)

1. A capacity-expandable hot-plug type battery power supply system is characterized by comprising an inverter box and at least one battery box;

the contravariant case includes:

the inversion module is used for converting the direct current into alternating current;

the charging module is used for converting alternating current into direct current;

the alternating current output port is used for inputting alternating current;

the alternating current input port is used for outputting alternating current;

the battery box includes:

the power supply port is used for connecting the battery box to the inverter box;

the communication interface is used for constructing a distributed network of the battery box and switching the battery box for supplying power or charging through the distributed network;

the inversion module is connected with the alternating current output port; the charging module is connected with the alternating current input port; the battery box is connected with the inverter box through the power port.

2. The expandable hot-plug type battery power supply system according to claim 1, wherein the inverter box further comprises:

the first bus bar and the second bus bar are used for being connected with a power interface of at least one battery box and receiving electric energy of the battery box or providing electric energy for the battery box;

the inversion starting switch is used for starting or closing the inversion module;

the battery box is respectively connected with one end of the first bus bar and one end of the second bus bar; the other end of the first bus bar is respectively connected with the input end of the inversion module and the output end of the charging module; the other end of the second bus bar is respectively connected with the input end of the inversion module and the output end of the charging module; the output end of the inversion module is connected with the alternating current output port, and the starting switch signal receiving end of the inversion module is connected with the inversion starting switch; the input end of the charging module is connected with the alternating current input port.

3. The system of claim 1, wherein the battery box further comprises:

a battery pack for storing or discharging electric energy;

the BMS module is used for monitoring and acquiring the voltage and the temperature of the battery;

the CPU processor is used for receiving signals and sending down control signals;

a DC/DC converter for outputting a fixed voltage;

the fan is used for cooling the battery box;

the main power switch is used for starting or closing the power input, the power output and the communication of the battery box;

an output control switch; a power output for turning on or off the battery box;

the output control switch is connected with the output control end of the CPU processor; the communication interface of the battery box is connected with the first communication port of the CPU processor; the second communication port of the CPU processor is connected with the BMS module, and the control port of the CPU processor is connected with the DC/DC converter; the information acquisition port of the BMS module is connected with the battery pack; the positive electrode of the battery pack is respectively connected with the first input end of the DC/DC converter and the positive electrode of the power supply port; the negative electrode of the battery pack is respectively connected with the second input end of the DC/DC converter and the negative electrode of the power supply port, the fan control port of the DC/DC converter is connected with the fan, the main power supply control port of the DC/DC converter is connected with the main power supply switch, and the interlocking signal port of the DC/DC converter is connected with the power supply port.

4. An expandable hot-pluggable battery power supply system according to claim 3, wherein the battery box further comprises:

the backflow prevention module and the main relay are used for preventing current from flowing backwards;

the input end of the backflow prevention module is connected with the anode of the battery pack; the output end of the backflow prevention module is connected with the positive pole of the main relay, a first control port of the backflow prevention module is connected with the CPU processor, a second control port of the backflow prevention module is connected with the DC/DC converter, and a pre-charging port of the backflow prevention module is connected with the positive pole of the power supply port; and the negative electrode of the main relay is connected with the positive electrode of the power port, and the two ends of the coil of the main relay are connected with the control port of the main controller of the DC/DC converter.

5. The system of claim 4, wherein the battery box further comprises:

the fuse is used for protecting the circuit when the circuit is abnormal;

one end of the fuse is connected with the input end of the backflow prevention module, and the other end of the fuse is connected with the anode of the battery pack.

6. An expandable hot-plug type battery power supply system as claimed in claim 5, wherein said battery box further comprises a display device, said display device being connected to said CPU processor.

7. An expandable hot-plug type battery power supply system as claimed in any one of claims 1 to 6, wherein the battery box is connected to and communicates with the battery box via CAN.

8. An expandable hot-plug type battery power supply system as claimed in any one of claims 1 to 6, wherein the bottom of the battery box is provided with pulleys.

9. A control method for power supply of an expandable hot-plug type battery power supply is characterized by comprising the following steps:

acquiring the number, the electric charge quantity and the temperature of the currently connected battery boxes;

selecting a battery box to supply power according to the charge quantity and the temperature;

updating the number, charge level and temperature of the battery boxes through a distribution network;

and switching the battery boxes to supply power according to the updated number, the electric charge amount and the temperature of the battery boxes.

10. The method as claimed in claim 9, wherein the step of updating the number, the amount of charge, and the temperature of the battery boxes via a distribution network comprises:

the battery box forms a distributed network through CAN communication;

acquiring the charge quantity and the temperature of the battery box;

and updating the charge quantity and the temperature of the battery boxes in the distributed network, and acquiring the number of the battery boxes.

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