초록 ▼

A unipolar ignition of the invention provides a current waveform at the ignitor plug which initially rises relatively slowly, followed by a transition to a fast rising current which quickly peaks and thereafter slowly dissipates. Such a current waveform provides an initially hotter and longer lastin

A unipolar ignition of the invention provides a current waveform at the ignitor plug which initially rises relatively slowly, followed by a transition to a fast rising current which quickly peaks and thereafter slowly dissipates. Such a current waveform provides an initially hotter and longer lasting spark which does not harm the ignitor plug of the system or shorten its life expectancy. Neither does the spark create stress on the solid state circuitry which delivers the energy to the ignitor plug. To provide the foregoing spark and current characteristics, an inductor having a saturable core is in series with the ignitor plug, and it provides an initially high inductance which limits the rate of current rise at the plug as energy is transferred from an energy storage device to the plug. As the current through the inductor increases, its core begins to saturate and the effective inductance begins to decrease, allowing the current to rise more quickly. As energy is transferred to the ignitor plug, the increasing saturation, decreasing inductance and increasing current complement one another, causing the rate of current rise to increase quickly to a high value desirable for ignition. Related features of the invention provide for easy diagnostics of the spark and for timing an ignition sequence and providing a repetition rate which aids in a successful ignition.

대표청구항 ▼

In a system for operating a turbine engine, a series connected energy source, first switch and ignition system, where the ignition system is responsive to the energy source and the first switch for igniting fuel for the turbine engine, the ignition system comprising: a converter responsive to the en

In a system for operating a turbine engine, a series connected energy source, first switch and ignition system, where the ignition system is responsive to the energy source and the first switch for igniting fuel for the turbine engine, the ignition system comprising: a converter responsive to the energy source for pumping energy from the energy source to a capacitor that accumulates the pumped energy; a second switch for transferring the energy accumulated by the capacitor to a spark gap device in order to generate a spark at the device; a logic circuit for controlling a sparking sequence that includes repetition of the spark for a predetermined period of time at a first average rate and thereafter at a second average rate, where the first average rate is greater than the second average rate; the logic circuit including means responsive to the application of energy to the converter by the first switch for synchronizing an initiation of the sparking sequence with an engine starting sequence.