| 摘要 |
PURPOSE:To reduce a switching loss and to suppress a temperature rise of a reactor, by separating the connection of a saturation reactor from a main circuit, and inserting it into a circuit containing an auxiliary thyristor for operating a main control element. CONSTITUTION:Even if a gate signal has been applied to an auxiliary thyristor 6 at time t1, a main thyristor 1 does not conduct around the time t2 when a saturable reactor 7 is saturated. At the time t2, a pulselike current iG (t) flows to a gate of the main thyristor 1 from the thyristor 6, and the thyristor 1 is ignited. When terminal voltage V1 (t) of the thyristor 1 has dropped to a low value, the thyristor 1 conducts, and also a switching loss P' (t) is greatly reduced since an overlapped portion to a terminal current i1 (t) is a little. When the thyristor 1 conducts, the thyristor 6 is biased in the reverse direction, and it is turned off. |
