AI Power Grid Revolution: WPG Infusing Partners with Infineon to Capture SST Market Opportunities

As applications such as AI data centers, energy storage, and electric vehicle (EV) charging rapidly evolve, market demand for high-efficiency power conversion continues to grow. Traditional line-frequency transformers now face challenges in efficiency and space utilization. To address this, WPG Holding (3702-TW), through its subsidiary Infusing Group, has partnered with Infineon Technologies to host an online seminar titled 'Infineon SST Technology and Application Analysis.' The event focuses on the design and application of Solid-State Transformers (SST), driving innovation in sectors including data centers, energy storage, and EV charging.

Chen Wai-Hua, Product Manager at Infusing Group, stated that compared to conventional line-frequency transformers, SST integrates electrical isolation, voltage conversion, and reactive power compensation via power electronics technology. This integration improves system efficiency by at least 1%, reduces space occupancy and weight by over 30%, and offers fast response times and flexible modular scalability. These advantages significantly simplify the power conversion chain and enhance overall energy efficiency.

Data centers represent one of the key application areas for SST. From early UPS power supplies and HVDC-dominated architectures to Panama power integration and optimization, power delivery systems have continuously evolved—improving both efficiency and integration. As an 'energy router,' SST provides high-frequency isolated AC or DC interfaces on the medium-voltage side, supporting unidirectional or bidirectional power flow for localized autonomy. It also integrates power management, energy management, and fault management functions, enabling more flexible power dispatching among generation, storage, and consumption units.

In terms of topology, SSTs are primarily categorized into 2-Level and 3-Level architectures, consisting of three main stages: high-voltage rectification, isolated conversion, and low-voltage inversion. The high-voltage rectification stage commonly employs Cascaded H-Bridge (CHB) or Modular Multilevel Converter (MMC) topologies.

For medium-voltage AC/DC stage solutions, the CHB topology uses a distributed independent DC bus design, offering electrical isolation benefits. With fewer components and no need for arm inductors, it enables higher power density. It can be paired with ISOP-configured distributed high-frequency transformers and supports bypass derating operation.

Although it cannot directly output medium-voltage DC, CHB features moderate control complexity and excellent Total Harmonic Distortion (THD) performance, making it suitable for applications such as data center power supply, energy storage systems, and V2G charging stations.

In SST solution design, silicon carbide (SiC) components are key to enhancing system performance. Chen noted that compared to traditional silicon-based devices, SiC excels in bandgap, critical breakdown field, thermal conductivity, and electron saturation drift velocity. To meet various bus voltage requirements, Infineon offers a comprehensive SiC portfolio at 1,200V, 2,000V, 2,300V, and 3,300V, reducing the number of series connections and simplifying topological structures—thereby improving system reliability and power density.

On the product front, Infineon’s CoolSiC™ series provides a full range of packaging options—from discrete components to power modules—including TO-247 and QDPAK packaged discretes, as well as Easy, 62mm, and XHP series power modules, covering diverse power-level application needs.

The Easy series stands out for its high flexibility and scalability, offering substrate-less package configurations at 12mm height and supporting customization for special applications. Currently, the Easy B series has entered mass production, while the Easy C and Easy HD3 series continue to advance, creating further optimization opportunities for high-voltage application efficiency.

For medium-to-high power applications, Infineon’s 62mm modules offer two main product lines at 1,200V and 2,000V, featuring multiple on-resistance specifications and all based on half-bridge topology, allowing flexible combinations to build complex circuits according to system needs. For high-voltage, high-power applications, the XHP series modules support up to 2,300V and allow selection between copper or aluminum-silicon carbide substrates to reduce thermal resistance, meeting demands from solar inverters and energy storage systems.

Additionally, Infineon provides a complete ecosystem including SiC MOSFETs, SiC diodes, and gate driver ICs specifically designed for CoolSiC MOSFETs. This end-to-end solution—from power components to drive control—helps customers build highly efficient and reliable SST systems.