The NdFeB alloy was melted in a vacuum mid-frequency induction furnace and then homogenized.
钕铁硼合金用真空中频感应炉熔制。
2
Venation wave spectrum analysis finds out shape-structure change of mid-frequency signal fluctuation.
脉络波谱图分析查明了中范围（频率）信号波动的形态结构变化。
3
Full bridge topology was used in the main circuit, IGBT was used as power switching device, and micro-crystal core was used in mid-frequency transformer.