"Comprehensive Overview of Energy Storage System Architecture"
Release Date: March 21, 2025, 20:00
 
I. Overall Architecture of Energy Storage Systems
Energy storage systems consist of four core units that collaboratively achieve energy storage, conversion, and management:
1. Energy Storage Unit
◦ Function: Stores and releases electrical energy.
◦ Key Storage Media:
■ Lithium-ion batteries
■ Lead-acid batteries
■ Pumped hydro storage
■ Compressed air energy storage
■ Flywheel energy storage
2. Energy Conversion Unit
◦ Core Device: Power Conversion System (PCS)
◦ Role: Bidirectional AC/DC conversion:
■ Charging: AC → DC (grid → storage)
■ Discharging: DC → AC (storage → grid/load)
3. Energy Management Unit
◦ Function: The "brain" of the system:
■ Real-time data collection (storage capacity, charge/discharge status, grid load)
■ Optimization scheduling strategies
■ Coordinated control of multiple energy systems
4. Monitoring and Protection Unit
◦ Safety Mechanisms:
■ Real-time monitoring of voltage, current, and temperature
■ Abnormal condition alerts (overheating, overcharge/over-discharge)
■ Automatic cooling activation or circuit interruption
 
II. Energy Storage System Architecture Types
1. Centralized Energy Storage System
◦ Features: Large-capacity battery bank + centralized PCS
◦ Advantages: Simple structure, easy control
◦ Challenges:
■ "Bucket effect" (performance limited by the weakest cell)
■ Inter-cell loop current risks
■ Wider failure impact range
◦ Applications: Grid-side storage, large-scale renewable energy plants
2. Distributed Energy Storage System
◦ Features: Decentralized deployment + flexible grid connections
◦ Advantages: Localized supply-demand balancing, enhanced renewable energy integration
◦ Challenges: Complex coordination, higher maintenance costs
◦ Applications: User-side systems, microgrids, distributed power sources
3. String-Type Energy Storage System
◦ Features: Modular design + independent PCS (one string per controller)
◦ Strengths:
■ High efficiency (eliminates string current in