公开(公告)号：US20190131791A1

公开(公告)日：2019-05-02

申请号：US16176528

申请日：2018-10-31

Applicant: Hatch Ltd.

Inventor： Michael Morgan CAMPBELL ,  Yan ELKSNIS ,  Dong SHEN

IPC: H02J3/18 ,  H03K17/72 ,  H05B7/18

Abstract: A configuration of switches added to a line control circuit allows for switching back and forth between a configuration featuring a series-connected thyristor switch and reactor and a configuration featuring a parallel-connected thyristor switch and reactor. Connecting the reactor in series with the thyristor switch allows a controlled high-impedance circuit configuration that is particularly well adapted for cold furnace start-ups and furnace idling. In this manner, there is reduced need for such equipment as extra startup transformers, alternate low-voltage power supply configurations and temporary specialty electrical apparatus for cold furnace start-ups.