Fixed-frequency ignition circuit used for aero-engine start ignition

Abstract

The invention provides a fixed-frequency ignition circuit used for aero-engine start ignition. The fixed-frequency ignition circuit is composed of an EMI filtering unit, an auxiliary power supply, a discharge frequency generator, a self-simulated flyback converter, a rectification and energy storage unit, a discharge switch, a discharge pulse signal sampling and shaping unit and a discharge frequency control signal synthesis unit. The discharge pulse signal sampling and shaping unit and the discharge frequency control signal synthesis unit are the key to the fixed-frequency ignition circuit, and the discharge pulse signal sampling and shaping unit extracts a discharge current signal in a discharge circuit through a sampling resistor of tens of ohms to obtain a discharge pulse signal. The discharge frequency control signal synthesis unit conducts segmentation processing on the frequency signal, generated by the discharge frequency generator, according to the discharge pulse signal to generate a self-simulated flyback converter work control signal; and it is ensured that an ignition system just conducts one time of charging and discharging within a set charge-discharge period, and the ignition system can conduct discharge pulse energy output according to the fixed discharge frequency signal provided by the discharge frequency generator.

Description

technical field [0001] The invention belongs to the technical field of starting and ignition of aero-engines, in particular to a fixed-frequency ignition circuit for starting and igniting of aero-engines. Background technique [0002] The aero-engine starting ignition system consists of an ignition device, an ignition cable and an ignition nozzle, such as figure 1 shown. [0003] The working principle of the aero-engine starting ignition system: the ignition device converts the low-voltage electric energy provided by the engine power supply into high-voltage pulse electric energy, transmits it to the ignition nozzle through the ignition cable, and releases it instantly at the discharge end of the ignition nozzle to generate high-power discharge sparks. It is used to ignite the fuel and air mixture in the combustion chamber of the engine, and then start the engine. [0004] The spark frequency of the existing domestic aero-engine starting and ignition system is in a non-fix...

AI Technical Summary

Problems solved by technology

[0008] Aiming at the problem that the spark frequency of the existing ignition device changes greatly with the voltage of the power supply, combined with the technical indicators of the discharge spark energy and discharge spark frequency of the existing aero-engine start-ignition system, the present invention proposes an aero-engine start-ignition The fixed-frequency ignition circuit solves the problems existing in the existing aero-engine starting and ignition devices, and provides more advanced starting and ignition system products for aero-engines in my country

Images