The invention discloses a
plasma ignition circuit capable of adaptively adjusting
voltage frequency. A power supply VCC is connected to a high-
voltage arc striking circuit and a high-frequency
pilot arc circuit, and the high-
voltage arc striking circuit and the high-frequency
pilot arc circuit are both connected to the ground; the arc striking positive end and the arc striking negative end of the high-voltage arc striking circuit are connected to the output protection circuit, the
pilot arc positive end and the pilot arc negative end of the high-frequency pilot arc circuit are connected to the output protection circuit, and the output positive end and the output negative end of the output protection circuit are connected with an ignition electric
nozzle of the aero-engine. The high-voltage arc striking circuit is used for generating high-voltage and low-
current voltage pulses and
puncturing a
discharge gap of the ignition electric
nozzle after being output by the output protection circuit; the high-frequency pilot arc circuit is used for generating a high-frequency
voltage source through a high-frequency
sine wave signal, and the high-frequency
voltage source generated by the high-frequency pilot arc circuit is used for generating an
electric arc after a
discharge gap of the ignition electric
nozzle is broken down, so that an ignition function is realized; wherein the high-frequency pilot arc circuit is internally provided with two MOS (
Metal Oxide Semiconductor) tubes, the two MOS tubes are alternately conducted in a positive
half cycle or a negative
half cycle of a high-frequency
sine wave signal, and a resonant loop is formed in the high-frequency pilot arc circuit, so that current in the circuit is output to the ignition electric nozzle according to sine
waves of resonant frequency. According to the technical scheme, the problems that an existing
capacitive energy storage ignition circuit is usually applied to a low-power
ignition system with the power smaller than 100 w, and the high-altitude ignition effect is poor are solved.