What's the relationship between AI data centers, solid-state transformers, and plastic optical fibers?
The introduction of plastic optical fibers into AI data centers isn't necessarily for high-speed transmission; their primary purpose may be high-voltage electrical isolation.
The introduction of plastic optical fibers into AI data centers isn't necessarily for high-speed transmission; their primary purpose may be high-voltage electrical isolation.
However, as the power density of AI server racks increases, another type of fiber optic demand is emerging: high-voltage isolation for control signal transmission within power electronic devices.
One device worth noting is the solid-state transformer (SST).
1
Why are AI data centers starting to focus on 800V DC?
As AI server power continues to increase, low-voltage, high-current power distribution will result in thicker copper busbars, greater losses, and higher heat dissipation and space constraints.
Therefore, 800V DC has become one of the power supply architectures worth paying attention to for next-generation high-power AI data centers.
2
What is SST?
Traditional power frequency transformers mainly achieve voltage transformation and electrical isolation through electromagnetic induction of a 50/60 Hz AC magnetic field.
SST (Solid State Transformer) introduces power electronic conversion technology. Taking an SST architecture for 800V DC power distribution as an example: Medium-voltage AC → Power electronic conversion → High-frequency AC → High-frequency isolation transformer → Rectifier/DC-DC → 800V DC
Its core is not "no transformer", but upgrading the traditional power frequency transformer to: power semiconductor + high frequency magnetic device + digital control system, thereby realizing voltage conversion, electrical isolation and digital control.
3
Why does SST require optical fiber?
MW-level SSTs can use modular, cascaded power units. There may be a large potential difference between different power units or control domains, but it is still necessary to transmit signals such as PWM, Enable, Fault, synchronization and status feedback.
Therefore, the core value of optical fiber in SST is not necessarily "high speed," but rather: cross-potential electrical isolation + EMI immunity + avoidance of ground loops + improved fault isolation capability.
4
Why might POF have an opportunity?
SST internal control links are relatively short, limiting the need for ultra-high bandwidth. The focus is more on: electrical isolation, EMI immunity, reliability, installation tolerance, and cost.
Therefore, POF is not competing with MPO or LC high-speed links here, but is more likely to be used for: short-range, cross-potential isolated communication within power electronic devices.
5
Does SST always use POF?
SST has a need for cross-potential isolation communication, and some short-range, low- to medium-speed control links have the potential to use POF.
In practical applications, the choice between POF, HCS/H-PCF, or silica fiber still needs to be made based on temperature, distance, bandwidth, insulation, and reliability requirements.
6
More noteworthy: Industrial-grade POF harnesses
For POF harnesses to be used in high-power equipment such as SST systems, "large core diameter and easy connection" are not enough. They also need to meet requirements for: operating temperature, thermal aging, flame retardancy, vibration, bending radius, connection reliability, and insertion loss.
Therefore, more attention should be paid to products geared towards industrial environments: High-temperature, high-reliability POF harnesses. The product focus will also shift from single optical fibers to: Fiber optic cables + connectors + transceiver adapters + harness reliability.
7
Summarize
AI data centers are forming a new technology chain:
Increased computing power → Increased power → High-voltage DC power distribution → SST/SiC → Transpotential isolation → Fiber optic communication
The opportunity for POF (Polyfiber Optic) in AI data centers may not lie in replacing silica fiber in 400G and 800G high-speed communications, but rather in its integration into power electronic devices such as SST (Silicon Storage Technology), energy storage PCS (Power Conversion System), and inverters, undertaking short-distance control and cross-potential optical communication.
This could become a noteworthy new application direction for industrial POF.
RSPOF Optoelectronics: Making every optical transmission more stable.
Focusing on POF, industrial fiber optic patch cords, and fiber optic communication solutions. For questions regarding selection, parameter matching, and link applications, feel free to contact us privately. Follow us for continuous sharing of practical fiber optic technology and application knowledge..
