CN212434701U

CN212434701U - Marine lithium battery module health monitoring system based on double CAN bus redundancy

Info

Publication number: CN212434701U
Application number: CN202021332902.2U
Authority: CN
Inventors: 时斌; 王之民; 赵翔; 陈松涛
Original assignee: Zhenjiang Saiernico Automation Co ltd; Southeast University
Current assignee: Zhenjiang Saiernico Automation Co ltd; Southeast University
Priority date: 2020-07-08
Filing date: 2020-07-08
Publication date: 2021-01-29
Anticipated expiration: 2030-07-08

Abstract

The utility model discloses a marine lithium battery module health monitoring system based on double CAN bus redundancy, which comprises a plurality of module health monitoring devices, wherein the module health monitoring devices are correspondingly arranged in each lithium battery module, a plurality of lithium battery modules are connected in series to form a lithium battery module string, and the module health monitoring device in each independent lithium battery module is communicated with a lithium battery management system in a high-speed CAN communication mode; the module health monitoring device in each lithium battery module comprises an embedded microcontroller unit, a simulation front end, a balance control circuit, a simulation switch, a switch power supply and a protection driving circuit, wherein the embedded microcontroller unit is powered by the switch power supply, the embedded microcontroller unit is respectively connected with the simulation front end, the balance control circuit and the protection driving circuit, and the balance control circuit is connected with the simulation switch. The utility model provides a high-speed transmission of the monitoring data of the massive electric core in a large amount of battery modules of lithium battery management system management and control.

Description

Marine lithium battery module health monitoring system based on double CAN bus redundancy

Technical Field

The invention relates to a high-reliability marine lithium battery module health monitoring device based on double CAN bus redundancy, and belongs to the technical field of lithium batteries.

Background

The shipping industry, as a main carrier of economic globalization, makes a great contribution to economic trade worldwide. At present, the ship mainly depends on the marine diesel engine to provide power for navigation, so that resource exhaustion and deterioration of ecological environment are aggravated. Therefore, green ships have become the direction of future ship development. As a pure electric ship taking a lithium iron phosphate battery as a unique power source, the quality of the technical state of the lithium battery pack has very important influence on the normal operation of the ship. If the shipman can master the actual technical state of the lithium battery pack in real time, and the scientific use and reasonable maintenance of the lithium battery pack are realized on the basis of the actual technical state, the working reliability and the safety of the lithium battery pack can be effectively guaranteed. However, the reliability of the current marine lithium battery module detection device is low, and when large-scale analog quantity transmission is involved, the speed is low, and the real-time performance is not high. In addition, the temperature acquisition cannot meet the relevant regulations of the classification society, and the purpose of measuring the temperature of the all-single battery cell cannot be achieved; the existing charge and discharge protection measures are not enough to consider the change rate of temperature rise.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention aims to provide a marine lithium battery module health monitoring device based on dual CAN bus redundancy.

In order to achieve the purpose, the invention adopts the technical scheme that:

a marine lithium battery module health monitoring system based on double CAN bus redundancy comprises a plurality of module health monitoring devices, wherein each module health monitoring device is correspondingly arranged in each lithium battery module, the plurality of lithium battery modules are connected in series to form a lithium battery module string, and the module health monitoring device in each independent lithium battery module is communicated with a lithium battery management system in a high-speed CAN communication mode;

the module health monitoring device in each lithium battery module comprises an embedded microcontroller unit, a simulation front end, a balance control circuit, a simulation switch, a switch power supply and a protection driving circuit, wherein the embedded microcontroller unit is powered by the switch power supply, the embedded microcontroller unit is respectively connected with the simulation front end, the balance control circuit and the protection driving circuit, and the balance control circuit is connected with the simulation switch.

The embedded microcontroller unit of the module health monitoring device in each lithium battery module comprises a CAN FD interface and a CAN interface, and the module health monitoring device is respectively hung on the two sets of CAN buses through the CAN FD interface and the CAN interface.

Has the advantages that: the utility model discloses a CANFD communication has solved the high-speed transmission of the monitored control data of the massive electric core in a large amount of battery modules of whole lithium Battery Management System (BMS) management and control, utilizes the redundant communication framework of two CAN buses to improve the communication reliability between module health monitoring device and lithium Battery Management System (BMS) simultaneously.

Drawings

Fig. 1 is a schematic structural diagram of a lithium battery module health monitoring system;

FIG. 2 is a schematic structural diagram of a module health monitoring device;

FIG. 3 is a working process of a lithium battery module health monitoring system;

fig. 4 shows a comparison of CAN and CANFD frame structures.

Detailed Description

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

As shown in fig. 1, the utility model discloses a marine lithium battery module health monitoring system based on two CAN bus redundancy, including the healthy monitoring device of a plurality of modules, every module is healthy monitoring device and is corresponded to set up in every lithium battery module, and a plurality of lithium battery module establish ties and constitute a lithium battery module cluster, and the module health monitoring device in every independent lithium battery module communicates with lithium battery management system through high-speed CAN communication mode.

As shown in fig. 2, the module health monitoring device in each lithium battery module includes an embedded microcontroller unit, an analog front end, a balance control circuit, an analog switch, a switching power supply, and a protection driving circuit, wherein the embedded microcontroller unit is powered by the switching power supply, the embedded microcontroller unit is connected to the analog front end, the balance control circuit, and the protection driving circuit, and the balance control circuit is connected to the analog switch. The embedded microcontroller unit of the module health monitoring device in each lithium battery module comprises a CAN FD interface and CAN interfaces, and the module health monitoring device is respectively hung on the two sets of CAN buses through the CAN FD interface and the CAN interfaces.

The embedded microcontroller unit is used for being responsible for whole module health monitoring device's operation and data communication, and the simulation front end is used for pressing 1 to all monomer electric cores in the lithium battery module: and 1, acquiring the terminal voltage and the electrode temperature in an acquisition ratio.

For satisfying marine lithium battery power supply system to the demand of power, generally need establish ties a plurality of lithium battery module and constitute a lithium battery power supply system in groups with parallelly connected mode again, be in voltage-sharing safe operating condition for guaranteeing among the whole lithium battery power supply system between every battery module and each inside electric core of battery module, module health monitoring device adopts passive equalization technique in charging process, accomplish the balanced management that discharges of lithium battery electricity core promptly through analog switch's on-off control, ensure the voltage balance between every inside electric core of every lithium battery module and every lithium battery module.

As an optimal technical scheme, an S32K144 embedded microcontroller chip of Enzhipu is adopted as an embedded microcontroller unit in each module health monitoring device, and a 12-to-5V circuit is adopted to supply power to a single chip microcomputer. The analog front end adopts an analog front end MC33772 of Enzhipu to collect voltage, temperature and current of the battery cell. Because MC33772 can collect 6 paths of voltage, 7 paths of temperature and 1 path of current at maximum, the voltage and temperature collection ratio of 1: 1. a CAN communication interface provided by the embedded microcontroller unit and a CAN FD high-speed communication interface form a double-speed (high and low speed) double-CAN redundant communication architecture.

As shown in fig. 3, the working process of the present invention is: the terminal voltage and the electrode temperature of each battery cell in each lithium battery module are collected at regular time through the simulation front end, and when the battery is fully charged, the embedded microcontroller unit sends out an instruction to drive the relay to act and disconnect the charging switch; the module health monitoring device in each independent lithium battery module is respectively hung on two sets of CAN buses through a CAN FD interface and a CAN interface to form a communication bus redundancy framework and complete data transmission and information sharing with a lithium Battery Management System (BMS), namely, the lithium Battery Management System (BMS) shares voltage, current and temperature data of the battery modules under control through double CAN bus communication, and issues a voltage balance control instruction according to the terminal voltage of the module to ensure the voltage balance between each battery module. And the lithium Battery Management System (BMS) processes and records the temperature information collected by the analog front end, and sends out an alarm signal according to the monitored temperature rise change rate and a set threshold value.

The utility model discloses a terminal voltage and the electric current of electric core in each battery module are regularly gathered to module health monitoring device's embedded microcontroller unit control simulation front end, have realized the collection to each monomer electricity core temperature very much. When charging and discharging, the embedded microcontroller unit of the module health monitoring device drives the contactor of the charging loop to act, so that the charging and discharging safety of the battery module is ensured; and then, the embedded microcontroller unit of the module health monitoring device transmits the acquired data to a lithium Battery Management System (BMS) through a CAN FD interface and a CAN interface through double CAN bus communication. The lithium Battery Management System (BMS) receives electric quantity and temperature data of the battery modules of the module health monitoring devices, and sends balance control signals to each module health monitoring device, and the bottom module health monitoring devices perform passive balance control on the corresponding battery modules after receiving commands of the lithium Battery Management System (BMS).

Fig. 4 shows a comparison of CAN and CANFD frame structures. Traditional CAN communication CAN transmit 8 bytes, while CANFD CAN transmit up to 64 bytes, making the effective bit ratio of each frame higher. The transmission rate of the CAN bus is 1M/s at the most, while the CANFD CAN theoretically be 10M/s, which is achieved by the BRS bit speeding up the transmission after arbitration. The CRC check function of CANFD communication has higher performance than CAN communication, and the risk of undetected errors is reduced. The CANFD has the performances of shorter delay time, better real-time performance, higher bandwidth and the like. Relatively less overhead means better data throughput, and the software is simpler and more efficient when sending larger data objects. This is very important for the lithium battery management system that needs massive battery power information and temperature information transmission, and especially when the scale of the BMS system is larger, the advantage of CANFD is more obvious.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims

1. The utility model provides a marine lithium battery module health monitoring system based on two CAN bus are redundant which characterized in that: the system comprises a plurality of module health monitoring devices, wherein each module health monitoring device is correspondingly arranged in each lithium battery module, a plurality of lithium battery modules are connected in series to form a lithium battery module string, and the module health monitoring device in each independent lithium battery module is communicated with a lithium battery management system in a high-speed CAN communication mode;

2. The marine lithium battery module health monitoring system based on dual CAN bus redundancy of claim 1, characterized in that: the embedded microcontroller unit of the module health monitoring device in each lithium battery module comprises a CAN FD interface and a CAN interface, and the module health monitoring device is respectively hung on the two sets of CAN buses through the CAN FD interface and the CAN interface.

3. The marine lithium battery module health monitoring system based on dual CAN bus redundancy of claim 1, characterized in that: the embedded microcontroller unit is S32K 144.

4. The marine lithium battery module health monitoring system based on dual CAN bus redundancy of claim 1, characterized in that: the analog front end is MC 33772.