The islanding effect — a situation where distributed power sources continue to supply power to local loads after a public grid outage — is a critical safety hazard in solar power generation systems. To address this risk, global regulations require rapid disconnection from the grid during outages to avoid the dangers associated with islanding. However, Hinen's newly launched 5kW single-phase AC coupled residential energy storage system (AC5S) offers an innovative solution. It can swiftly switch to off-grid mode within 10 milliseconds of a grid failure and simulate grid functionality to keep photovoltaic (PV) inverters running, converting solar energy into electricity for home use or battery storage.
Technical Details
How AC5S Ensures Continuous Operation of PV Inverters
- Emergency Power Supply (EPS): The AC5S features a multi-functional generator interface that can connect to the output of PV inverters, making it suitable for homes with existing PV systems. In off-grid mode, the EPS function provides stable voltage and frequency, simulating a normal grid environment to ensure that connected PV inverters can seamlessly switch and continue operating even during grid outages.
- High-frequency SPWM Modulation and High-precision PLL Technology: These advanced technologies are used to generate near-sinusoidal voltage outputs, ensuring that the inverter's output voltage remains synchronized with the grid, thereby supporting stable power conversion.
- Voltage Feedforward Control and Bidirectional DC/DC Converter: Advanced control strategies and converter designs ensure that the system maintains a stable DC bus voltage under various conditions, achieving efficient energy management and smooth mode switching.
- Built-in Islanding Detection Function: The system can automatically detect changes in grid status and immediately switch to a safe off-grid operation mode during grid outages.
System Advantages
1. Uninterrupted Power Supply: The unique design of AC5S allows PV inverters to continue operating during grid failures, providing reliable power to users.
2. Strict Safety Assurance: Utilizing RoCoF (Rate of Change of Frequency) technology, the system ensures compliance with anti-islanding regulations under all circumstances, safeguarding the safety of users and maintenance personnel.
3. Optimized Energy Utilization: The intelligent management system effectively uses surplus power to charge batteries, improving energy efficiency.
4. Rapid Response Capability: Millisecond-level grid connection/disconnection switching times minimize the impact on household appliances.
5. Convenient Remote Monitoring: The accompanying Hinen app allows users to easily manage and monitor system performance.
Conclusion
The Hinen 5kW single-phase AC coupled residential energy storage system (AC5S) represents a significant advancement in modern residential energy storage. It not only addresses the challenge of continuous PV system operation during grid failures but also offers a highly intelligent energy management solution. By integrating the latest power electronics and smart software, AC5S provides users with a safer, more reliable, and environmentally friendly energy choice, contributing to a more robust and sustainable future.
