三变科技(002112.SZ)：公司产品主要为油浸式变压器、干式变压器等

Group 1 - The company, Sanbian Technology, primarily produces oil-immersed transformers, dry-type transformers, and combined transformers [1] - These products are mainly used for power conversion, transmission, boosting, and stepping down [1] - The applications of these products are widespread, including use by State Grid Corporation and photovoltaic enterprises [1]