What are the ignition systems of cars?

Engine ignition system can be divided into traditional battery ignition system, electronic ignition system, microcomputer-controlled ignition system and magneto ignition system according to its composition and different ways of generating high voltage electricity.

Traditional battery ignition systems use batteries and generators as power sources. With the help of the ignition coil and the circuit breaker, the low-voltage direct current of 6V, 12V or 24V provided by the power supply is converted into high-voltage electricity, which is distributed to the spark plugs of each cylinder through the distributor, so that an electric spark is generated between the two electrodes of the spark plug and the combustible mixture is ignited. The traditional battery ignition system is gradually replaced by electronic ignition system and microcomputer-controlled ignition system because of its shortcomings such as low high voltage, unreliable high-speed operation and frequent inspection and maintenance during use.

The electronic ignition system takes the storage battery and the generator as the power supply. The low-voltage electricity provided by the power supply is converted into high-voltage electricity through the ignition coil and the ignition controller composed of semiconductor devices (transistors), and then distributed to the spark plugs of each cylinder through the distributor, so that an electric spark is generated between the two electrodes of the spark plug to ignite the combustible mixture. Compared with the traditional battery ignition system, it has the advantages of reliable ignition and convenient use, and is widely used in automobiles at home and abroad.

The microcomputer-controlled ignition system is the same as the above two ignition systems. The battery and generator are used as power supply at the same time. The low-voltage electricity of the power supply is converted into high-voltage electricity through the ignition coil, and then the high-voltage electricity is distributed to the spark plugs of each cylinder by the distributor. The microcomputer control system sends out the ignition control signal according to the information provided by various sensors reflecting the engine working conditions, controls the ignition time and ignites the combustible mixture. The distributor can also be cancelled, and the microcomputer control system can directly distribute the high-voltage electricity to each cylinder. Microcomputer-controlled ignition system is the latest ignition system, which has been widely used in various middle and high-grade cars.

The magneto ignition system directly generates high-voltage electricity from the magneto itself, and there is no need to set up another low-voltage power supply. Compared with the traditional battery ignition system, the magneto ignition system generates high voltage electricity and works reliably in the middle and high speed range of the engine. However, when the engine speed is low, the generated high voltage is low, which is not conducive to engine starting. Therefore, the magneto ignition system is mostly used in racing engines that mainly work at high speed and full load, as well as some starting engines of motorcycle engines and high-power diesel engines without batteries.