According to statistics from the China Association of Automobile Manufacturers, my country's new energy vehicles will continue to grow explosively in 2022, with sales exceeding 6.8 million, ranking first in the world for eight consecutive years, maintaining a "fast lane" development trend, and attracting great attention from Western developed countries. A considerable number of countries try to establish new international trade barriers based on the carbon emissions of the entire life cycle of products: the European Union stipulates that the carbon emissions of new passenger cars in the country shall not exceed 95g/km; Regulations on the present value of a car's carbon footprint. The low-carbonization level of automobiles and the carbon emission intensity of products will be the core competitiveness of future automobile companies.
In order to meet the challenges, my country has formulated a series of development plans, pointing out the direction for the development of intelligent new energy vehicles: "14th Five-Year Plan" national key research and development of new energy vehicles to deepen the "three vertical and three horizontal" research and development layout, proposed the vehicle platform, energy Power, electric drive system, intelligent driving, vehicle-network integration and supporting technology in six major research areas. Among them, power batteries have become the focus of competition in the field of intelligent networked new energy vehicles in the future. How to ensure the safety, efficiency and environmental protection of new energy vehicle power batteries within the full life cycle under the "dual carbon" goal has become a low-carbon transformation of my country's auto industry. important issues in the process.
01. Digital twin
With the vigorous development of digital technology, digital twins, Internet of Things and other technologies have been widely used in the industrial field, and also provide cutting-edge technical support such as new strategies and new ways for the upgrade of power batteries. The digital twin creates a digital model of a physical entity in a real environment through digital means, providing the development team with the capabilities of data fusion, two-way feedback, real-time interaction, decision analysis and rapid iterative optimization, making the physical space and information space of the power battery full life cycle efficient collaboration is possible. Car companies such as CATL and BYD have carried out forward-looking technology research on this, and improving battery management capabilities through digital twin technology has gradually become the development trend of the power battery industry.
The battery management system (Battery Management System, hereinafter referred to as BMS) is one of the core subsystems of the power battery energy storage system. It is responsible for monitoring the operating status of each battery in the battery energy storage unit to ensure the safe and reliable operation of the energy storage unit. The BMS can monitor and collect the state parameters of the energy storage battery in real time, and exchange information with other devices through the interface to ensure the safety of the new energy vehicle power battery.
In the field of full-digital virtual simulation, a virtual model of an automobile BMS can be built based on SkyEye, a domestically-made full-digital real-time simulation software of Tianmu:
The virtual battery management system based on SkyEye has the following advantages:
- No need to care about the cumbersome connection relationship of real cables, the project is built once and can be continuously reused;
- Simulate real CAN bus and BMS controller hardware, support almost unlimited number of simulated hardware;
- Support the operation of OS and application programs that conform to the AUTOSAR protocol;
- Integrating the original CANoe host computer software, real data can be simulated and injected through the SkyEye GUI interface.
The virtual battery management system based on digital twin technology can greatly save the development time and cost of new energy vehicle power batteries, reduce physical deployment and maintenance costs, and its flexibility and scalability can adapt to battery systems of different types, sizes and configurations , and can also be adaptively adjusted according to changing battery technology and application requirements to adapt to future expansion and upgrades. The virtual BMS system allows users to intuitively understand the battery status, performance and health status to achieve optimal battery usage and performance.
02. Power battery life cycle management framework
Since each stage of the power battery life cycle has different problems and characteristics, combined with the interaction and connection between each stage, a power battery life cycle management framework driven by digital twins can be built, as shown in the following figure:
Through information interaction between modules, the whole life cycle management of power batteries can form a whole of collaborative operation, mainly involving real-time data perception and collection, modeling and simulation, data management and service technology, which can effectively support the green, low-carbon and safety of power batteries Efficient overall design forms a virtuous cycle of the whole life cycle of the power battery by improving the design quality.
references
*Zhang Yu. Sun Fengchun: Dual Carbon Strategy Leads the Green Revolution of Automobiles [J]. China Industry and Information Technology, 2022(1):54-57.
*Fan Weijun, Pan Jianxin, Wang Yali. Research on Lifecycle Management of Power Batteries Driven by Digital Twins[J]. Automotive Digest, 2023(5): 38-44.