How Car Charging System Works

A vehicle is handicapped without a charged battery. If the battery is not optimally charged,the vehicle is bound to produce problems leaving you no option, but to visit a car battery charging station. Before you visit one, know how the car charging system works.

Purpose of a Car Charging System

The main function of a car charging system is to generate pressure and electrical current flow to recharge and maintain the charge in the battery while the engine is running. It induces voltage for the car’s electrical system to run when the car is moving and generates electric current flow to top up the charge in the battery. The whole charging system is composed of an alternator, rectifier, voltage regulator, 3 Pairs of positive biased diodes, and a battery. Simply put, the purpose of the charging system is to convert alternative current into direct current to charge the vehicle’s battery.

Battery Charging Techniques:

Vehicle’s battery normally operates on direct current mode and to charge it, an alternator issue which generates alternative current. There are two battery charging techniques: Constant Voltage Charging and Constant Current Charges. Usually, in all modern vehicles, a constant voltage charging technique is used.

How does a car charging system work?


The main purpose of an alternator is to generate alternative current and convert it into direct current in the required amount for the battery to charge. The alternator charging system consists of a rotor, rectifier, voltage regulator, and 3 pairs of biased diodes.


The purpose of the rotor is to generate a magnetic field to produce current. A set of three conductor coils known as a stator coil is attached to the surrounding of the rotor at 120 degree intervals. When the rotor completes one rotation, each stator coil generates a positive charge with the rotation and delivers three-phase current supply in the output.


As the Alternator cannot produce direct current on its own, it’s necessary to connect it to a rectifier. A three pair of forward bias diodes is attached in the rectifier for three-phase supply. The diode is connected in parallel to two outputs so that all the 3 pairs can be accessed through one connection. Whenever three-phase current is passed into the diode, the positive biased diode filters and separates positive and negative supply of the current due to which the alternative current is converted into direct current.

Voltage Regulator:

The purpose of the voltage regulator is to regulate the power of the battery. It controls the voltage of the rotor coil, which indirectly controls the output of the alternator. In case of a high voltage generation by the Rectifier, it cuts down the voltage in the rotor and decreases the power of the magnetic field thereby controlling the output of the alternator. During this process, a reverse EMF is generated inside the entire three stator coils due to which the current is automatically balanced. For routine maintenance of your car’s battery, contact us. We are a reputed car charging center in Pune that provides all brand car repair and maintenance services.

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