Principle of ignition coil
Apr 16, 2020
Leave a message
principle：
There are two sets of coils in the normal ignition coil, the primary coil and the secondary coil. The primary coil is thicker enameled wire, usually around 0.5-1 mm enameled wire around 200-500 turns; the secondary coil is thinner enameled wire, usually around 0.1 mm enameled wire around 15000-25000 turns. One end of the primary coil is connected to the low-voltage power supply (+) on the vehicle, and the other end is connected to the switching device (breaker). One end of the secondary coil is connected to the primary coil, and the other end is connected to the output end of the high-voltage line to output high-voltage electricity.
The reason why the ignition coil can change the low-voltage electricity on the car into a high voltage is because it has the same form as an ordinary transformer, and the primary coil has a larger turns ratio than the secondary coil. But the working mode of the ignition coil is different from the ordinary transformer. The working frequency of the ordinary transformer is fixed at 50Hz, also known as the power frequency transformer, and the ignition coil works in the form of pulse, which can be regarded as a pulse transformer. It varies according to the engine. The rotation speed repeats the energy storage and discharge at different frequencies.
When the primary coil is connected to the power supply, a strong magnetic field is generated around the current as the current increases, and the iron core stores the magnetic field energy; when the switching device disconnects the primary coil circuit, the magnetic field of the primary coil rapidly attenuates, and the secondary coil High voltage will be induced. The faster the magnetic field of the primary coil disappears, the greater the current at the moment of current disconnection, and the greater the turns ratio of the two coils, the higher the voltage induced by the secondary coil.
The reason why the ignition coil can change the low-voltage electricity on the car into a high voltage is because it has the same form as an ordinary transformer, and the primary coil has a larger turns ratio than the secondary coil. But the working mode of the ignition coil is different from the ordinary transformer. The working frequency of the ordinary transformer is fixed at 50Hz, also known as the power frequency transformer, and the ignition coil works in the form of pulse, which can be regarded as a pulse transformer. It varies according to the engine. The rotation speed repeats the energy storage and discharge at different frequencies.
When the primary coil is connected to the power supply, a strong magnetic field is generated around the current as the current increases, and the iron core stores the magnetic field energy; when the switching device disconnects the primary coil circuit, the magnetic field of the primary coil rapidly attenuates, and the secondary coil High voltage will be induced. The faster the magnetic field of the primary coil disappears, the greater the current at the moment of current disconnection, and the greater the turns ratio of the two coils, the higher the voltage induced by the secondary coil.
Type:
According to the magnetic circuit, the ignition coil can be divided into two types: open magnetic type and closed magnetic type. The traditional ignition coil is of the open magnet type. Its iron core is made of silicon steel sheets of about 0.3 mm, and the iron core is wound with secondary and primary coils. The closed magnetic type uses an iron core of shape III to wind the primary coil, and then the secondary coil is wound outside. The magnetic force line is formed by the iron core to form a closed magnetic circuit. The advantages of closed-magnet ignition coils are less magnetic leakage, less energy loss, and smaller size, so electronic ignition systems generally use closed-magnet ignition coils.
For more information,please contact us at sales@xfullstar.com