TWM626999U - A battery energy storage system supporting ups with a neutral line. - Google Patents

Abstract

This invention relates to a lithium battery energy storage system supporting UPS with a neutral line, comprising a lithium battery pack and a UPS host. The lithium battery pack is connected to the positive and negative electrodes of the UPS host through a battery management system, and the positive lead of the lithium battery pack is connected in parallel with a charging switch and a discharging switch on the upper half of the lithium battery pack, and the charging switch and the discharging switch on the upper half of the lithium battery pack are respectively connected in series with a diode. The negative electrode of the lithium battery pack is connected in parallel with a charging switch and a discharging switch on the lower half of the lithium battery pack, and the charging switch and the discharging switch on the lower half of the lithium battery pack are respectively connected in series with a diode. A battery neutral line is disposed between the lithium battery pack and the UPS host. According to the lithium battery energy storage system supporting UPS with neutral line, separating the charging and discharging circuits, monitoring and controlling the upper and lower parts independently for charging in the BMS can solve not only the problem of overcharging and over discharging of the battery, but also effectively solve the problem of voltage capacity inconsistency of the upper and lower half of the battery.

Description

Supports lithium battery energy storage system with centerline UPS

This creation relates to power supply guarantee equipment, in particular to a lithium battery energy storage system supporting a neutral uninterruptible power system (UPS).

Uninterruptible power supply system (UPS) power supply, namely uninterruptible power supply, is a system equipment that connects the battery with the host, and converts DC power into commercial power through the host inverter and other modular circuits. At present, in the field of uninterruptible power supply (UPS) power supply, the proportion of lead-acid solutions is as high as 90%. However, in recent years, the rapid development of lithium battery technology has gradually highlighted its advantages. Compared with traditional lead-acid batteries, lithium batteries have With the advantages of high energy density, small size, large discharge rate, light weight, long life, and wide operating temperature range, the lithium battery uninterruptible power system (UPS) solution has become a new choice for customers.

Uninterruptible power system (UPS) is divided according to the working frequency of the designed circuit, which can be divided into power frequency machine and high frequency machine. The power frequency machine is designed based on the traditional analog circuit principle. The internal power components of the machine (such as transformers, inductors, capacitors, etc.) are large. Generally, there is less noise when running with a large load. In the environmental conditions of the power grid, the anti-resistance performance is stronger, and the reliability and stability are stronger than those of the high-frequency machine. The high-frequency machine uses a microprocessor (CPU chip) as the processing control center. It burns the complicated hardware analog circuit into the microprocessor, and controls the uninterruptible power system (UPS) by software program. run. Therefore, the volume is greatly reduced, the weight is greatly reduced, the manufacturing cost is low, and the selling price is relatively low. The inverter frequency of high frequency machine is generally above 20KHZ. However, the high-frequency machine has poor tolerance under harsh power grid and environmental conditions, and is more suitable for environments with relatively stable power grids, less dust, and suitable temperature/humidity.

In actual use, the high-frequency UPS needs to be connected to the neutral line, which divides the battery pack into upper and lower parts. The floating charging voltage and charging current are sufficient; and if the lithium battery adopts the lead-acid method, it is easy to cause the lithium battery pack to be overcharged or overdischarged.

In view of the current situation of the above-mentioned prior art, the technical problem to be solved by this creation is to provide a support belt center line that not only solves the problems of battery overcharge and overdischarge, but also effectively solves the inconsistency of voltage and capacity between the upper and lower half of the lithium battery pack Lithium battery energy storage system for Uninterruptible Power System (UPS).

The technical solution adopted by this creation to solve the above technical problems is: a lithium battery energy storage system supporting a neutral uninterruptible power system, including a lithium battery pack and an uninterruptible power system (UPS) host, the lithium battery pack is powered by a battery The management system is connected to the positive and negative poles of the UPS host, and the positive lead of the lithium battery pack is connected in parallel with the upper-half charging switch of the lithium battery pack and the upper-half discharge switch of the lithium battery pack, and the upper half of the lithium battery pack is connected in parallel. The charge switch and the discharge switch of the upper half of the lithium battery pack are respectively connected in series with diodes; the negative lead of the lithium battery pack is connected in parallel with the charge switch of the lower half of the lithium battery pack and the discharge switch of the lower half of the lithium battery pack. The lower half charging switch and the lower half discharging switch of the lithium battery pack are respectively connected in series with diodes, and a battery neutral line (M) is arranged between the lithium battery pack and the UPS host.

Further, the battery management system includes a microcontroller (MCU) and a A current sensor, a human-machine interface (HMI), a battery management unit (BMU) and a main positive contactor connected to the controller (MCU), the battery management unit is respectively connected to the positive and negative electrodes of the single battery, and the current sensing There is an analog-to-digital converter between the device and the microcontroller (MCU), where: The current sensor is used to detect the current of the lithium battery pack; the battery management unit (BMU) is used to detect the voltage of the single battery; the human-machine interface (HMI) is used for the communication between the system and the user. media for interaction and information exchange. Further, the battery management system communicates with the uninterruptible power system (UPS) host through RS232, RS485, CAN communication protocols, or the battery management system communicates with the dry contact and wet contact of the uninterruptible power system (UPS) host. signal output.

Compared with the prior art, the beneficial effects of this creation are: this solution uses the battery management system (BMS) to separate the charge and discharge circuits, and the upper and lower parts independently monitor and control the charging, which not only solves the problem of battery overcharge, Over-discharge problem, and can effectively solve the voltage and capacity inconsistency of the upper and lower half of the battery. This creative design is suitable for large-scale promotion.

ADC: Analog to Digital Converter

Bat-up: the upper half of the lithium battery pack

Bat-down: The second half of the lithium battery pack

B+: Positive pole of lithium battery pack

B-: negative electrode of lithium battery pack

CAN: communication protocol

D1, D2, D3, D4: Diodes

K1, K3: Discharge switch

K2, K4: charging switch

M: Neutral

UPS: Uninterruptible Power System

UPS+: Positive pole of uninterruptible power supply system

UPS-: Uninterruptible Power System Negative

BMU: Battery Management Unit

HMI: Human Machine Interface

MCU: Microcontroller

Fig. 1 is a circuit connection diagram of the first embodiment of the present invention; Fig. 2 is a connection block diagram of the battery management system of the present invention; Fig. 3 is a circuit connection diagram of the second embodiment of the present invention.

The following will be combined with the accompanying drawings in the embodiments of the present invention, which are preferred embodiments of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in this creation, those of ordinary skill in the art All other embodiments obtained by members without creative work fall within the scope of the protection of this creation.

For the convenience of description, it appears in the following: the discharge switch in the upper half of the lithium battery pack is represented by K1, the charging switch in the upper half of the lithium battery pack is represented by K2, and the discharge switch in the lower half of the lithium battery pack is represented by K3 . The charging switch in the lower half of the lithium battery pack is represented by K4.

FIG. 1 is a circuit connection diagram according to an embodiment of the present invention; as shown in FIG. 1 , the lithium battery energy storage system supporting a neutral uninterruptible power supply system includes a lithium battery pack and an uninterruptible power supply system (UPS) The host, the lithium battery pack is connected to the positive and negative poles of the uninterruptible power system (UPS) host through the battery management system, and the positive lead of the lithium battery pack is connected in parallel with the charging switch in the upper half of the lithium battery pack and the discharge in the upper half of the lithium battery pack switch, the upper half of the lithium battery pack charge switch and the upper half of the lithium battery pack discharge switch are connected in series with diodes respectively; the negative lead of the lithium battery pack is connected in parallel with the lower half of the lithium battery pack charge switch and the lower half of the lithium battery pack Section discharge switch, the lower half of the lithium battery pack charge switch and the lower half of the lithium battery pack discharge switch are connected in series with diodes respectively, and a battery neutral is provided between the lithium battery pack and the UPS host. line (M).

FIG. 2 is a connection block diagram of the battery management system of the present invention; the battery management system includes a microcontroller (MCU), a current sensor connected to the microcontroller (MCU), a human-machine interface (HMI), a battery A management unit (BMU) and a main positive contactor, the battery management unit is respectively connected with the positive and negative electrodes of the single battery, an analog-to-digital converter is arranged between the current sensor and the microcontroller (MCU), wherein: all The current sensor is used to detect the current of the lithium battery pack; the battery management unit (BMU) is used to detect the voltage of the single battery; the human machine interface (HMI) is used between the system and the user A medium for interaction and exchange of information.

The battery management system communicates with the uninterruptible power supply system (UPS) host through RS232, RS485, CAN communication protocols, or the battery management system performs signal output through the dry contact and wet contact of the uninterruptible power system (UPS) host.

The battery management system monitors the voltage and temperature of all single batteries, and controls the charging switches: K2, K4 to open or close, and discharge switches: K1, K3 to open or close according to information such as voltage, current, and temperature.

working principle: The upper part of the charging circuit

UPS+→K2→D2→BAT+→M

When the battery management system detects that the cell voltage is overcharged, overtemperature, or overcharged, the switch K2 is turned off, otherwise it is turned on.

Upper part discharge circuit

BAT+→D1→K1→UPS+→M

When the battery management system detects that the cell voltage is over-discharged, over-temperature, or over-discharged, the switch K1 is opened, otherwise it is closed.

The lower part of the charging circuit

M→BAT-→D4→K4→UPS-

When the battery management system detects that the cell voltage is overcharged, overtemperature, or overcharged, the switch K3 is turned off, otherwise it is turned on.

Lower half discharge circuit

M→UPS-→K3→D3→BAT-

When the battery management system detects that the cell voltage is over-discharged, over-temperature, or over-discharged, the switch K3 is opened, otherwise it is closed.

FIG. 3 is a circuit connection diagram of the second embodiment of the present invention.

The difference between this embodiment and Embodiment 1 is that a plurality of lithium battery packs can be designed in a modular manner. Specifically, every two lithium battery packs are distributed symmetrically up and down, and the lithium battery pack placed at the upper end adopts Embodiment 1. The wiring structure of the upper half of the lithium battery pack in Example 1; the lithium battery pack placed at the lower end adopts the wiring structure of the lower half of the lithium battery pack in Example 1; and so on, the management of multiple lithium battery packs can be realized, and the Power system (UPS) expansion lithium battery energy storage system.

Compared with the prior art, the beneficial effects of this creation are: this solution uses the battery management system (BMS) to separate the charge and discharge circuits, and the upper and lower parts independently monitor and control the charging, which not only solves the problem of battery overcharge, Over-discharge problem, and can effectively solve the voltage and capacity inconsistency of the upper and lower half of the battery. This creative design is suitable for large-scale promotion.

For those skilled in the art, it is obvious that the present creation is not limited to the details of the above-mentioned exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or essential characteristics of the present creation. Therefore, the embodiments are to be regarded in all respects as exemplary and not restrictive, and the scope of the invention is defined by the appended claims rather than the foregoing description, and is therefore intended to fall within the scope of the claims. All changes within the meaning and scope of the equivalents of , are included in this creation. Any reference signs in the claims shall not be construed as limiting the involved claim.

Bat-up: the upper half of the lithium battery pack

Bat-down: The second half of the lithium battery pack

B+: Positive pole of lithium battery pack

B-: negative electrode of lithium battery pack

CAN: communication protocol

D1, D2, D3, D4: Diodes

K1, K3: Discharge switch

K2, K4: charging switch

M: Neutral

UPS: Uninterruptible Power System

UPS+: Positive pole of uninterruptible power supply system

UPS-: Uninterruptible Power System Negative

Claims (3)

A lithium battery energy storage system supporting an uninterruptible power system with a center line, comprising a lithium battery pack and a host of the uninterruptible power system, wherein the lithium battery pack is connected to the positive and negative poles of the host of the uninterruptible power system through a battery management system, and is characterized in that The positive lead of the lithium battery pack is connected in parallel with the upper half of the lithium battery pack and the upper half of the lithium battery pack. The polar body; the negative lead of the lithium battery pack is connected in parallel with the lower half of the lithium battery pack and the lower half of the lithium battery pack. The lower half of the charge switch and the lower half of the lithium battery pack are respectively Diodes are connected in series, and a battery neutral line is arranged between the lithium battery pack and the host of the uninterruptible power system. The lithium battery energy storage system supporting a neutral uninterruptible power system according to claim 1, wherein the battery management system includes a microcontroller, a current sensor connected to the microcontroller, a human A computer interface, a battery management unit and a main positive contactor, the battery management unit is respectively connected with the positive and negative electrodes of the single battery, and an analog-to-digital converter is arranged between the current sensor and the microcontroller, wherein: the current The sensor is used to detect the current of the lithium battery; the battery management unit is used to detect the voltage of the single battery; and the human-machine interface is used for the interaction and information exchange between the system and the user. The lithium battery energy storage system supporting a neutral uninterruptible power system according to claim 1, characterized in that the battery management system communicates with the host of the uninterruptible power system through RS232, RS485, CAN The communication protocol is used for communication, or the battery management system outputs the signal through the dry contact and wet contact of the uninterruptible power system host.

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