There is a growing global consensus on the strong trend towards Solid-State Transformers (SST), according to a research report. Progress in SST technology has been frequent since 2026. Multiple domestic companies have successively launched prototype products; overseas startups are securing intensive funding, accelerating commercialization; and leading global power equipment companies are hastening the deployment of SST products. It is widely agreed that SST is the ultimate solution for data center power architecture. Following its commercialization, SST's market penetration is expected to rise rapidly, reaching a trillion-dollar scale by 2030. Opportunities across the SST industry chain are set to move upward in unison. The main viewpoints are as follows:
Global Consensus on the Strong SST Trend
In October 2025, a white paper proposed that the Solid-State Transformer (SST) is the ultimate solution for providing 800V direct current, capable of directly stepping down 13.8/35kV AC from the medium-voltage grid to 800V DC in a single stage. At the current stage where SST technology is not yet mature, industrial-grade rectifiers at the 7.5MW level can also be used to rectify medium-voltage AC to DC in one step, eliminating most intermediate conversion steps and reducing energy loss. A report presented at the OCP Summit similarly pointed to solid-state transformers as the ultimate future power architecture solution. A consensus has formed that SST is the endgame for data center power architecture. Progress on SST has been frequent since 2026. In March 2026, a joint implementation plan for high-quality development of energy-saving equipment was issued, listing large-capacity solid-state transformers as a key promotion direction for the first time. Several domestic enterprises have launched prototype products. Since 2026, a number of companies have introduced prototypes, with leading firms already in the process of customer sampling and engagement. Overseas startups are securing intensive funding, accelerating commercialization. A U.S. SST platform developer completed a $60 million financing round in February 2026, with participation from several industry players and selection of a key SiC supplier. Another company completed a $140 million financing round in February 2026, announcing plans to build production capacity in the U.S. A Singapore-based company incubated by a university secured $80 million in funding in November 2025, focusing on hyper-scale AI data center clients. Leading overseas power equipment companies are accelerating SST product deployment. One company expects progress on product delivery for hyper-scale data center clients by autumn 2026, with more orders possible by 2027; another company guides that SST order progress is expected around the second half of 2026.
SST as the Ultimate Form of Future 800V Architecture
Combining analysis data, the transition to 800V DC can be described as progressing through four distinct stages. 1) Stage 1/2: White Space Retrofit / Native 800V DC System Phase, expected to begin from late 2026 / early 2027. This involves upgrading/retrofitting existing AC distribution to 800V DC. Stage 1 is an early development phase driven by hyperscale data centers willing to pay a premium for future adaptability and efficiency gains, as rack densities have not yet hit physical limits. It largely retains original transformers, UPS, switchgear, etc., outputting 800V DC into racks via integrated power racks/sidecars. Stage 2 commences as native 800V DC servers begin shipping at scale. Around 2028, with the volume production of native 800V DC chip systems, 800V DC will become necessary as physical and rack density limits are approached. 2) Stage 3: Rewriting the Electrical Architecture, expected around 2028. This phase eliminates low-voltage UPS, replacing them with facility-level AC/DC rectifiers, reducing unnecessary conversion steps. Grey space power is converted from 415V AC directly to 800V DC via rectification. However, it still requires introducing 480V AC power from the low-voltage side of the medium-voltage transformer. Stage 3 extends 800V DC distribution across the entire facility. 3) Stage 4: The Ultimate SST Architecture. The main change is replacing the low-voltage transformer and AC-DC rectifier with a single SST device that can convert directly from medium voltage to 800V DC.
The Scale of the SST Market – Projected to Grow Significantly to Trillion-Dollar Level by 2030
The report clearly identifies four core directions for AI data center power: 1) The power supply unit (PSU) segment, including PSUs, HVDC, SST, etc., where value is most concentrated and power density iteratively upgrades. 2) Core components essential for achieving DC and high-power conversion, such as solid-state circuit breakers, CBU/BBU, DC/DC converters, and high-frequency isolation transformers. 3) Power station-level energy storage to ensure safe, efficient, and fast grid integration for data centers. 4) Third-generation semiconductor components like SiC and GaN for power electronics conversion. Based on assumptions about future AI data center scale, the report projects the market space for HVDC, SST systems, and components under an optimistic scenario. The results show: 1) Scale: The SST market is projected to reach a trillion-dollar scale by 2030. The PSU market is expected to reach a scale of hundreds of billions by 2030, while HVDC and SST are projected to reach a trillion-dollar scale by 2030. PSUs and power supplies outside the rack represent the highest value segments. 2) Trend: Focusing on power supplies outside the rack: ① SST technology is expected to gradually commercialize around 2027/2028. Given SST is globally recognized as the ultimate data center architecture solution, its penetration rate is expected to increase rapidly during 2028-2030 post-commercialization. ② Traditional UPS remains mainstream in the near term, holding the highest share, with its market size reaching tens of billions under improvements from medium-voltage UPS upgrades. ③ HVDC market penetration is expected to rise rapidly in the coming years, approaching a trillion-dollar market scale near 2030. 3) Market: The overseas market size is projected to be larger than the domestic market. Due to greater incremental power consumption from new AI chips overseas and higher unit value of overseas products, the market size for power supplies (inside and outside racks) overseas is expected to exceed the domestic market by 2030, offering greater market space.
SST Industry Chain Opportunities Poised for Upward Movement in Unison
From an iteration perspective, as various 800V architectures evolve, equipment can be categorized into three core types: new additions, upgrades, and those being phased out. 1) SST Host & Upstream (New Additions): From an endgame perspective, SST, as the ultimate solution, is expected to show the most significant long-term growth. ① For SST hosts, the market is expected to grow rapidly post-commercialization around 2027/2028, potentially reaching a trillion-dollar scale by 2030. ② For SST components, costs are primarily composed of power semiconductors, high-frequency transformers, DC capacitors, and cooling systems. Power semiconductor devices account for 30-40% of the cost, high-frequency transformers for 10-20%; semiconductor devices and high-frequency transformers are core SST components. Medium-voltage high-frequency transformers play a critical role in SST, with high technical barriers in insulation materials/magnetic materials. The high-frequency transformer in SST provides electrical isolation and enables conversion from medium-voltage input to low-voltage output, serving as the channel for bidirectional energy transfer, directly determining the system's power capacity and transmission efficiency. ① Insulation Materials: At high frequencies, insulation materials are more prone to partial discharge, accelerating insulation aging and leading to breakdown. Special insulation materials and processes are required. ② New Magnetic Materials: Traditional silicon steel suffers from high eddy current losses at high frequencies, necessitating the use of high-frequency, low-loss materials like soft ferrites, amorphous/nanocrystalline alloys, or magnetic powder cores. Therefore, in high-frequency transformers, insulation materials and magnetic materials present high technical and process barriers. SiC power devices are increasingly becoming the preferred choice for SST components. The main technical challenge for power electronic converters lies in voltage withstand capability, as they must directly handle medium-voltage (10kV level) AC. This requires third-generation wide-bandgap semiconductor materials like SiC MOSFETs. SiC MOSFETs can withstand voltages up to 10-15kV while reducing switching and conduction losses to optimize the system, making them an increasingly preferred option for SST manufacturers. 2) Secondary & Tertiary Power Supplies (Upgrades): Will increase with the overall expansion of AI data center demand and the emergence of new requirements. Secondary Power: PSUs will add an 800V/±400V to 50V/12V conversion stage. With HVDC adoption, the PSU performing AC/DC conversion is moved from the computer rack to the HVDC sidecar, eliminating the AC/DC stage inside the rack. The 800V/±400V DC power entering the rack cannot be used directly, requiring the addition of an 800V/±400V to 50V/12V DC/DC conversion stage. Tertiary Power: Voltage Regulator Modules (VRMs) are beginning to adopt vertical power delivery (VPD) technology. Due to the large chip area, if current enters from the side, high impedance can cause significant voltage drop. To address this, the VRM on a specific board is mounted directly on the back of the PCB beneath the GPU, allowing current to pass vertically through PCB vias directly into the GPU core, greatly shortening the power delivery path and saving space on the front side. 3) Components (Upgrades): ① Although in the ultimate SST architecture, traditional UPS and multiple rectification stages are replaced, there is common demand for some core components, along with upgrade requirements under 800V high-voltage systems. Examples include supercapacitor CBUs, DC circuit breakers, and DC fuses. ② Under the high-voltage trend, demand for upstream components like SiC & GaN power devices across various segments is expected to increase significantly.
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