In today's energy sector, energy storage technology is playing an increasingly critical role. As a leading company in the lithium battery manufacturing field, Bonnen is dedicated to unveiling the key technologies within energy storage systems, including Battery Management Systems (BMS), Energy Management Systems (EMS), and Power Conversion Systems (PCS).
Energy storage systems are technologies that store electrical energy for later use. They help balance the supply and demand on the grid, improve energy utilization efficiency, and reduce dependence on traditional energy sources. A complete electrochemical energy storage system primarily consists of battery packs, BMS, EMS, PCS, and other electrical equipment.
In an energy storage system, the battery pack sends status information to the BMS. The BMS shares this information with the EMS and PCS. Based on optimization and scheduling decisions, the EMS sends control information to the PCS and BMS, directing the charging and discharging processes of individual batteries or battery packs.
By integrating advanced BMS, EMS, and PCS technologies, Bonnen ensures the optimal performance, reliability, and safety of energy storage systems, helping to lead the way in sustainable and efficient energy management.
What is PCS?
PCS (Power Conversion System) of energy storage system.
PCS can work in the following two states and therefore has two important functions:
1. Rectifier working state: convert the AC power of the grid into DC power when charging the battery cell of the energy storage system.
2. Inverter working state: convert the DC power of the battery cell into AC power and feed it into the grid when discharging the battery cell of the energy storage system;
Therefore, PCS is an important device for realizing bidirectional energy transfer between DC battery cells and AC grid.
In recent years, due to the development and performance improvement of new power electronic devices including IGBT (insulated gate bipolar transistor) and IGCT (integrated gate commutated thyristor), the production and application of high voltage and high power PCS devices have become a reality.
Specifically, Battery Management System BMS: plays a sensing role, mainly responsible for battery monitoring, evaluation, protection and balancing;
Energy Management System EMS: plays a decision-making role, mainly responsible for data collection, network monitoring and energy scheduling;
Energy Storage Converter PCS: plays an execution role, the main function is to control the charging and discharging process of the energy storage battery pack and perform AC/DC conversion.
What is BMS?
BMS (Battery Management System), commonly known as the battery nanny or battery steward, is a device that cooperates to monitor the status of energy storage batteries. BMS and battery cells together form a battery system.
BMS Function
BMS plays a sensing role in the energy storage system. Its main function is to monitor the operating status of each battery in the battery energy storage unit and ensure the safe operation of the energy storage unit.
BMS measures the basic parameters of the battery, including voltage, current, temperature, etc., to prevent overcharging and over discharging of the battery and extend the battery life.
BMS needs to calculate and analyze the battery's SOC (remaining battery capacity) and SOH (battery health status), and report abnormal information in a timely manner.
BMS Layered perception architecture
Most BMS systems are three-layer architectures, and the hardware is mainly divided into slave control unit, master control unit and master control unit.
1. Bottom layer: slave control BMU, which is the single cell management layer. It is composed of battery monitoring chip and its auxiliary circuits, responsible for collecting various types of information of single cells, calculating and analyzing the battery's SOC (remaining battery capacity) and SOH (battery health status), realizing active balancing of single cells, and uploading single cell abnormal information to the master control.
2. Middle layer: master control BCU, which is the battery pack management layer. Collect various single cell information uploaded by BMU and collect battery pack information. Calculate and analyze the SOC and SOH of the battery pack.
3. Upper layer: master control, which is the battery cluster management layer. Responsible for the overall coordination within the system and external information interaction with EMS and PCS, and control the operation process of the entire BMS system according to external requests.
Energy storage BMS development trend
Currently, BMS functions have evolved from basic functions such as monitoring, communication, protection, display, and storage to advanced functions such as battery system safety diagnosis and long-life operation and maintenance, and system economic index diagnosis.
From a technical point of view, active balancing technology will become the standard, and technologies such as big data and artificial intelligence will be applied to battery status algorithms; in the future, the survival space of low-end BMS suppliers will become smaller and smaller.
Intelligent operation and maintenance, advanced functions, etc. are the core points for differentiated competition among manufacturers in the future.
Deeply integrate big data management and cloud-edge collaboration.
Develop cloud-edge collaboration based on BMS, give full play to the data aggregation capabilities of BMS, realize the collection, analysis, status diagnosis and evaluation of real-time data of battery systems at the station-level equipment end, and realize data cleaning and pre-processing;
Based on more station-side data, the cloud can realize multi-dimensional spatiotemporal data mining, refining, and fine processing, realize more detailed and comprehensive evaluation of battery operation status, safety status, and energy storage system reliability, dynamically optimize BMS operation strategies and algorithm models and set them down to the equipment end, achieve the best safety and economic operation and maintenance mode, realize intelligent operation and maintenance, and provide data support for energy aggregation/distribution/trading, and provide guarantee for the value realization of energy storage systems.
What is EMS?
EMS (Energy Management System) is the decision-making center of the energy storage system and plays the role of "brain". Energy management systems include grid-level energy management systems and microgrid-level energy management systems. The EMS mentioned in energy storage systems generally refers to the microgrid level.
Composition
Energy management systems are generally divided into equipment layer, communication layer and application layer.
Equipment layer: requires energy acquisition and conversion (PCS, BMS) as support;
Communication layer: mainly includes links, protocols, transmission, etc.;
Information layer: mainly includes cache middleware, database, and server, among which the database system is responsible for data processing and data storage, records real-time data and important historical data, and provides historical information query;
Application layer: The manifestations include APP, Web, etc., providing managers with a visual monitoring and operation interface. The specific functions cover energy conversion decision-making, energy data transmission and collection, real-time monitoring and control, operation and maintenance management analysis, electric energy/power visual analysis, remote real-time control, etc.
EMS products generally serve as the hub for the interaction between energy storage systems and higher-level information systems.
Energy storage systems participate in grid dispatching, virtual power plant dispatching, "source-grid-load-storage" interaction, etc. through EMS.
To ensure the safe and reliable operation of energy storage systems, BMS, EMS and PCS need to have high reliability and high performance. As a professional lithium battery manufacturer, Bonnen has advanced technology and rich experience, and can provide customers with high-quality BMS, EMS and PCS products. If you are interested in energy storage systems, welcome to visit Bonnen's official website to learn more about energy storage systems.
