The ignition system is the most fundamental power source for engine operation, and the composition of the ignition system is relatively complex. After all, it is necessary to ensure that an electric spark can be generated inside the cylinder in a timely, accurate and reliable manner to ignite the combustible mixture and generate sufficient power. Currently there are three ignition systems, of which the electronically controlled ignition system is a new ignition system widely used in modern times.
At present, there are three kinds of ignition systems for automobile engines: traditional ignition system, electronic ignition system and microcomputer-controlled ignition system (with or without power distributor). Modern cars mostly use electronic ignition system, which is mainly composed of power supply, sensor, ECU, ignition controller, ignition coil, distributor, spark plug, etc. Composition; microcomputer-controlled ignition system mainly consists of sensors, ECU, ignition controller, ignition coil and spark plugs, etc. Composition.
In the composition of the ignition system, the ignition coil is a very important and relatively complex part, mainly composed of primary coil, secondary coil, iron core, etc.
First, the electronic control unit determines the best ignition advance angle and energizing time according to the sensor signal, and sends the command to the ignition device. Then, the ignition unit controls the ignition coil primary circuit according to the command. When the circuit is turned on, the primary circuit of the ignition coil is turned on. When the primary circuit is cut off, a high voltage is induced in the secondary coil, which is sent to the spark plug of the working cylinder through the distributor or directly, thus completing the ignition.
The sensor is used to check the engine condition information related to ignition and send the result as data ignition to and from the electronic control unit for control.
The electronic control unit is the control core of the electronic control system. It analyzes the data from the car sensor and sends the control signal of the optimal ignition advance angle and on-time of the primary circuit of the ignition coil to the controller after calculating and judging by the pre-programmed program.
Ignition is an electronic control which can amplify the ignition signal output from the electronic control system and drive the ignition coil to work.
The ignition coil can convert the power supply from 12V low voltage DC to 15-20kv high voltage DC. There is only one ignition coil in the electronically controlled ignition system with distributor, while there are multiple ignition coils in the system without distributor.
According to the ignition sequence of the engine, the distributor sends the high-voltage electricity generated by the ignition coil to the spark plugs of each cylinder in turn.
Spark plugs use the high voltage generated by the ignition coil to produce an electric spark to ignite the air-fuel mixture in the cylinder.