Nandu Power New Generation of Energy Storage BMS System Nears Mass Production

 

The Battery Management System (BMS) is a critical component to ensure the safe and efficient operation of new energy storage systems. Recently, Nandu Power successfully developed its new-generation 1500V liquid-cooled active balancing BMS system for energy storage, which has obtained GB34131-2023 type test CGC certification, IEC/UL60730 functional safety certifications, and certificates, qualifying it for sale in domestic, European, and American markets.

 

In recent years, new energy storage BMS systems have been increasingly trending toward a distributed multi-layer management framework and active balancing technology, while facing various technical challenges, such as difficulties in capturing cell internal temperature and calculating internal state. Nandu Power, with a deep understanding of the application needs and pain points of new energy storage BMS systems, has integrated AI and big data technology within the context of digital intelligence to develop its next-generation 1500V liquid-cooled active balancing BMS system.

 

This system boasts core advantages of standardization, modularity, and intelligence, and achieves full life-cycle, multi-dimensional management of energy storage batteries through a four-layer architecture: Data Collection Layer, Charge/Discharge Control Layer, System Management Layer, and Cloud Service Layer.

 

 

The data management layer collects cell voltage and temperature and includes active balancing functions to ensure cell consistency. The Nandu Storage BMS battery management chip is designed to automotive-grade standards, ensuring high precision and reliability in data collection over the entire system life cycle. Additionally, the temperature collection circuit features a three-tier protective design, effectively addressing the issue of temperature collection chip failure.

 

Moreover, the Nandu Storage BMS system is equipped with a bidirectional DCDC active balancing function, enabling energy transfer between any cells within a cluster. Utilizing single-cell SOC capacity difference technology, it addresses the timeliness and accuracy of balancing, providing a reliable guarantee for the efficient operation of energy storage batteries throughout their lifecycle.

 

Zhou Gang, Director of the Nandu Power Electronics Research Institute, stated, "To validate the active balancing effect of the BMS, we artificially created a 6Ah capacity difference in the system. After activating active balancing, the system's discharge capacity increased by 10Ah within 24 hours, not only filling the 6Ah single-cell capacity gap but also essentially eliminating the capacity gap generated over long-term operation, showing remarkable balancing effects."

 

 

The charge/discharge control layer manages the battery cluster charging and discharging process, performing real-time SOX estimates to prevent overcharging and over-discharging and implements a three-level protection system (primary warning, secondary alert, and tertiary protection).

 

With core technology overlay, Nandu Storage BMS has achieved an industry-leading voltage and current collection accuracy of 0.2% (industry standard is 1%) and zero-drift current below 10mA, reaching instrument-grade standards. This high level of precision provides a solid foundation for the high-accuracy estimation of SOC.

 

According to Zhou Gang, the SOC estimation of Nandu Storage BMS is based on ampere-hour integration and is refined through multiple dimensions and operating conditions, including dynamic, static, charge/discharge, and full-charge/discharge adjustments, fully meeting the power demand for peak shaving and frequency modulation in energy storage stations based on battery SOC.

 

 

The system management layer is responsible for local data collection and storage, enabling human-machine interaction, parameter setting, and multi-cluster parallel management.

 

Nandu Storage BMS employs a quad-core CPU processor with edge computing capabilities, where core management and protection strategies run on a separate CPU. This design ensures that even if some CPUs or software encounter issues, the system can still respond normally to EMS scheduling and stack-level protection strategies, ensuring system safety and controllability.

 

 

The cloud service layer handles big data management and analysis, supporting remote telemetry, telecommand, telecontrol, and tele-adjustment functions.

 

With a millisecond-level telemetry period for control signals and measurement signals within one second, Nandu Storage BMS allows after-sales engineers to easily obtain operational data and conduct data analysis and fault diagnosis remotely without needing to be on-site. Additionally, BAU, BCU, and BMU devices within the Nandu Storage BMS system support remote OTA upgrades.

 

Nandu Power has conducted continuous 12-month non-stop testing across various dimensions, including functionality, performance, reliability, safety, and durability, on the new generation 1500V liquid-cooled active balancing BMS system, meeting all design standards, with some indicators significantly surpassing industry standards. This system is expected to be delivered in bulk by the end of 2024.