Dry-type transformers with reduced dimensions for photovoltaic generation: benefits of recent developments and CompactCool

Photovoltaic generation demands transformers meeting specific installation and transport requirements for typical containerized or skid-based solutions. However, at the same time, main technology trends are requiring higher power ratings while the low voltage levels are maintained, pushing the current levels to the technical limits for installations. Thus, double-secondary is becoming a common configuration for transformers. This solution tends to increase equipment height, which is particularly stricter for dry-type transformers. Authors propose the use of recent developments to overcome those challenges while maintaining the key values of dry-type transformer technology (i.e., safety, environmental and low maintenance). Hitachi Energy overcomes these challenges with two different innovative solutions. One solution is regarding the use of a liquid cooling that circulates through the coils extracting its heat and a second solution which consists in a connection scheme that allows to reduce transformer height considerably.