Rectifier Efficiency

Losses in a rectifier consist of transformer, tube, and filter losses. Filament power should be counted as loss, especially when a tube rectifier is compared with a rotating machine or metal disk rectifier. In spite of this loss, a high-voltage polyphase rectifier of the mercury-vapor or pool type may have 95 per cent efficiency at full load. In contrast, the rectifier for a radio receiver rarely has more than 60 per cent efficiency. Reasons for this low figure are the high tube and reactor IR drops and low transformer efficiency. The filament power, too, is a greater portion of the total.