When we speak of capacitors applied to vehicles, primarily mean ignition system.
It began to use capacitors when it was contact, and used until now.
In the classical contact ignition systema capacitor connected in parallel to the breaker. Ignition coil (reel) is an auto-transformer, transformation ratio which is not so great. Therefore, the circuit breaker contacts when the voltage on its primary side abruptly increases from zero to the voltage on-board network, the amplitude of the pulse generated by the secondary winding, for the breakdown of the spark is missing. Simultaneously, the coil begins to accumulate energy in the form of a magnetic field. When the contact opens, this energy is released, and the primary winding of the findings appears self-inductance voltage greater than the voltage on-board network is almost 20 times. But for the emergence of the current voltage is not enough - you need as a closed circuit. Without it would form a capacitor battery and the spark between the contacts of the breaker, why would last much wear. If the circuit breaker is connected in parallel capacitor, current flows through it. On the secondary winding of the bobbin a voltage greater than the voltage on the transformation of the self-induction coefficient punched spark gap spark.
Principles of electronic ignition systemsdifferent. In some of them, as well as in contact, there is switching of the primary winding of the ignition coil fed from the onboard network, only this switching is performed in a contactless manner. In other board voltage is increased in advance of about 20 times the inverter. This voltage charges the capacitor. At the moment when the spark is required, the capacitor is closed on the reel and discharge it, then disconnects from it and re-charging of the converter. In systems of the second type are not sparking occurs at the time of opening and the time circuit.
Are used in capacitors andauxiliary nodes electronic ignition system. Such, for example, power filters, frequency control circuit converters and microprocessor systems - clocks. There used low-voltage capacitors small containers, so they are compact. But they are no less important for the smooth operation of the ignition and the engine of the whole system. If any one of them suddenly disappeared, the engine would have stopped immediately.