Abstract: A capacitive discharge ignition system is described that incorporates a two-terminal passive network for controlling the discharge of a capacitive energy storage device into an igniter plug, wherein the network comprises a solid-state switch for alternately providing high and low ohmic paths between the two terminals in order to selectively connect the capacitive energy storage device to the igniter plug. The passive network includes means responsive to a predetermined value of a voltage differential (&Dgr;V) between the two terminals for effecting the switching of the path between the two terminals provided by the solid-state switch from a high ohmic value to a low ohmic value, thereby controllably discharging the capacitive energy storage device into the igniter plug. In the illustrated embodiment, the solid-state switch is a series of SCRs, each of whose anode is connected to the trigger input of the SCR by way of a breakover diode (BOD).

Abstract: An ignition system is provided that marries a free-running discharge circuit with a fast-charging, high voltage converter without resulting in an excessive rate of discharge. To this end, the free-running discharge circuit employs a passive switch embodied either as a spark-gap device or a passive network of semiconductor elements. A feedback circuit detects discharge events at the discharge circuit and, in response thereto, selectively enables and disables the fast-charging converter. A spark rate clock is integrated into the feedback circuit for the purpose of setting the average discharge rate to a predetermined value.

Abstract: An exciter circuit for a gas turbine engine ignition system. A high voltage supply continuously charges a storage capacitor. A plurality of silicon controlled rectifiers (SCRs) are connected in series between the storage capacitor and a high voltage conditioning circuit. A multi-section protective network is connected in parallel with the series connected SCRs. Individual network sections are connected across separate ones of the SCRs. The SCRs are normally non-conducting and are periodically triggered to discharge the storage capacitor into the conditioning circuit. An igniter plug is connected to the output of the conditioning circuit. The protective network divides the voltage of the storage capacitor equally across the SCRs when the latter are non-conductive thereby reducing the voltage stress to which each of the SCRs is subjected.