| 摘要 |
PURPOSE:To improve the reliability of a controller, by adding a simple circuit to reduce the peak value of the reverse recovery current of a reverse conducting SCR by connecting a composite circuit, where a resistance and a capacitor are connected in parallel or series and in parallel to a saturable reactor, to a semiconductor element. CONSTITUTION:A composite circuit where a resistance and a capacitor 9 are connected in series or parallel and in parallel to a saturable reactor 7 is added to a circuit A' which varies the firing intervals of a reverse conducting SCR5 to control the average voltage of a load 2, and this composite circuit is connected to the SCR5. An anode reactor 6 is connected in series to this circuit A', and a circuit where a commutating reactor 3 and a comutating capacitor 4 are connected in series in connected in parallel to this circuit, thereby constituting a semiconductor controller. By addition of the composite circuit, the impedance of the reactor 7 is lowered transitionally to reduce the peak value of the reverse recovery current due to a residual carrier, thus improving the reliability of the controller. |
