Hoymiles’ latest string PCS, equipped with SiC-based power switching devices, can convert AC or DC power of up to 460 kW
The company’s grid-forming PCS can mitigate grid frequency disturbance within 100 ms
It supports black start during a dead grid and can form a microgrid during the absence of an AC grid
Module-level power electronics (MLPE) and energy storage solutions provider Hoymiles unveiled its latest power conversion systems (PCS) for utility storage applications at the Energy Storage International Conference and Expo 2026.
A PCS is a bidirectional power converter that is placed between battery banks and the grid terminal, inverting DC to AC and vice versa, forming an AC-coupling.
The company introduced its 460 kW string PCS, which is compatible with a variety of battery energy storage systems (BESS), including the PCS-MV station and the AC-block container. Compared to the centralized BESS architecture, it comprises multiple AC-coupled PCSs that eliminate ‘single point of failure’ risks.
In terms of performance, the string PCS features a 3-level conversion topology based on a Silicon Carbide (SiC) switching device, which the company claims yields more than 99% efficiency. A built-in circulating liquid-based cooling mechanism ensures stable full load operation at peak efficiency, even at 60°C, says Hoymiles. It adds that this PCS also extends the lifespan of core components by over 20%, thanks to its design, which allows internal temperature variation among multiple units within 2°C. However, Hoymiles didn’t share the reference value for this comparison.
The company showcased its 1,725 kW PCS, featuring grid-forming capability to ensure utility-scale grid stability. This PCS, when coupled with a battery bank, acts as a voltage source, rather than a conventional current source to the grid. It helps create an independent local grid with voltage and frequency. According to the company, this feature starts injecting or absorbing active power within 5 ms of a grid frequency disturbance. In the absence of rotating mass, instantaneous switching and active power generation provide inertia support to the grid, albeit passively. The company claimed that it can mitigate grid frequency disturbances within 100 ms, contributing to grid stability.
This PCS-based BESS can also serve as a power source for black start of a dead grid. In addition, its off-grid mode supports parallel control of multiple PCSs, creating a microgrid. Without sharing many technical details, the company stated it controls inrush current from the upstream transformer and line impedance due to the absence of a stable AC-side grid. As a result, it maintains microgrid stability.
The commercialization details for these PCSs were unknown at the time of this article’s publication.
