Zhiguang Electric Technology Decodes Cascaded Grid-Forming Energy Storage Technology
On May 14, 2026, at the 6th Shenzhen International Conference on New Energy Storage Technologies and Engineering Applications, Zhiguang Electric Technology Chief Technical Expert Sun Kaifa delivered a keynote speech titled “Key Technologies and Applications of Cascaded Grid-Forming Energy Storage Converters.”
In the presentation, Sun revealed how Zhiguang Electric Technology is building a “stability anchor” for modern power grids through advanced energy storage converter technology.
Under the new power system characterized by “dual-high” features — high penetration of renewable energy and high penetration of power electronic equipment — weak-grid challenges such as low inertia and insufficient grid support are becoming increasingly prominent. Grid-forming energy storage has emerged as a key solution to these challenges. As the core equipment enabling this transformation, the performance of energy storage converters directly determines the strength of grid support capabilities.
Inherently Grid-Forming: From Grid-Following to Grid-Forming
Compared with conventional low-voltage PCS solutions, Zhiguang Electric Technology’s cascaded high-voltage energy storage converter naturally possesses synchronous-generator-like characteristics through its unique topology and control strategy.
Direct Grid Connection: Transformer-free architecture with direct 6–35kV high-voltage output, enabling shorter electrical distance, lower internal impedance, and operational characteristics closer to synchronous generators.
Ultra-High Efficiency: Single-unit capacity of up to 50MW with conversion efficiency reaching 99%.
Robust Grid Support: Stable operation across a wide short-circuit ratio (SCR) range from 1.1 to 50, while supporting millisecond-level primary frequency regulation and inertia response.
Safe and Flexible Operation: Smooth four-quadrant operation with precise control and ultra-fast response; supports multiple operating modes including VSG, VF, and PQ; enables one-click black start and power-sharing for multi-unit parallel operation at 100MW-scale power stations.
This was also the core message repeatedly emphasized by Sun during his speech: whether in technical parameters or operational characteristics, the cascaded high-voltage direct-grid-connected solution is the power electronic conversion technology that most closely resembles synchronous generators, capable of fundamentally strengthening grid stability.
Seven Core Technologies Solving Power Station-Level Stability Challenges
If system topology forms the backbone, control technology serves as the soul. Sun highlighted seven key technologies developed by Zhiguang around grid-forming cascaded high-voltage direct-grid-connected energy storage systems, each targeting some of the most critical operational challenges in modern power systems.
1.Power Station-Level Frequency Support: Enabling wind farms to achieve stability characteristics comparable to conventional thermal power plants.
2.Millisecond-Level Continuous Frequency Support: Successfully completed fault ride-through and continuous frequency support testing.
3.Transient Voltage Support Across Wide SCR Conditions: Achieved grid fault ride-through under SCR ≥1.1 conditions, covering a wide SCR range from 1.1 to 20.
4.Black Start Capability for Grid-Forming Wind Farms: Solved stable black-start operation challenges for fully power-electronic-based stations, with technology applicable to various large-scale power station projects.
5.Short-Circuit Voltage Support for Networked Systems: Successfully completed station-level artificial short-circuit testing, overcoming large-disturbance stability challenges in fully power-electronic networked systems.
6.Magnetizing Inrush Current Tolerance and Multi-Unit Load Sharing: Demonstrated excellent inrush current tolerance while enabling highly accurate power sharing among parallel units, significantly simplifying black-start procedures.
7.Synchronization and Seamless Load Transfer with Coal-Fired Units: Achieved stable coordinated control throughout the entire process of black start, synchronization, and grid connection between energy storage systems and coal-fired generating units.
Expanding Application Scenarios: Building Stability Anchors for Every Weak Grid Point
Sun further explained that the cascaded grid-forming PCS equipped with the above capabilities has already demonstrated its value as a “grid stabilizer” in multiple benchmark industry projects.
In the CHN Energy Qinghai Dachaidan Hybrid Energy Storage Demonstration Project, the system acts as the “grid-forming brain,” integrating lithium batteries, supercapacitors, and multiple storage technologies to achieve the world’s first wide-timescale hybrid energy storage application.
In the Chuangyuan Metal 35kV Grid-Forming Energy Storage Project in Inner Mongolia — currently the largest user-side grid-forming energy storage project in China by installed capacity — the system enabled seamless “zero-perception” switching to microgrid operation during unexpected grid disconnection events.
Meanwhile, in the Qingyuan Independent Energy Storage Power Station Project in Guangdong, the technology supports Guangdong Province’s first GWh-scale standalone energy storage station, providing daily inertia support and dynamic reactive power compensation for the grid.
As an innovator in high-power power electronics technology, Zhiguang Electric Technology continues to drive industry advancement through breakthroughs in core technologies. Sun’s presentation not only demonstrated the company’s leadership in cascaded grid-forming energy storage converters, but also provided valuable insights for the upgrading and large-scale deployment of next-generation core energy storage equipment.
Looking ahead, Zhiguang Electric Technology will continue deepening its expertise in high-power power electronics, accelerating the deployment of cascaded grid-forming energy storage converters across broader application scenarios, and contributing core technological strength toward building a safer, more efficient, and greener next-generation power system in support of China’s dual-carbon goals.
