The charging system provides electrical energy for all of the electrical components on the vehicle.
The main parts of the charging system include, the battery, the alternator; the voltage regulator, which is usually integral to the alternator; a charge warning, or indicator light; and wiring that completes the circuits.
The battery provides the electrical energy for starting. Then, once the engine is running, the alternator supplies all electrical components of the vehicle. It also charges the battery to replace the energy used to start the engine. The voltage regulator prevents over-charging.
Concepts
It is important to understand that the generator creates an electric current, but does not create electric charge, which is already present in the conductive wire of its windings. It is somewhat analogous to a water pump, which creates a flow of water but does not create the water itself.
Voltage regulation is the ability of a system to provide near constant voltage over a wide range of load conditions.
Switched-mode power supply
A switched-mode power supply, or SMPS, is an electronic power supply unit (PSU) that incorporates a switching regulator — an internal control circuit that switches the load current rapidly on and off in order to stabilize the output voltage. Switching regulators are used as replacements for simpler linear regulators when higher efficiency, smaller size or lighter weight are required. They are, however, more complicated and more expensive, their switching currents can cause noise problems if not carefully suppressed, and simple designs can have a poor power factor.
SMPS can also be classified into four types according to the input and output waveforms, as follows:
DC to DC converter
In electrical engineering, a DC to DC converter is a circuit which converts DC power from one voltage to a another. It is a special class of power converter.
DC to DC converters are important in mobile devices such as cellular phones and laptop computers, which are supplied with power from batteries. Often space limitations in a device do not allow multiple batteries to supply different parts of the device.
One simple method of DC to DC conversion is a circuit known as a voltage divider. This technique involves inserting a resistor in series with the voltage supply to lower the voltage. However, this method suffers serious drawbacks:
Any kind of voltage regulator solves the first two problems. However, linear regulators still have the remaining three problems.
Recently, specialized devices have become available which convert from one DC voltage to another. These devices, a kind of switched-mode converter, generally perform the conversion by the following steps:
In general, the term "DC to DC converter" almost always refers to one of these switching converters.
Switching DC to DC converters are available in a wide variety of input and output voltages. Commonly used converters include 3 V to 5 V, 12 V to 5 V, and +10 V to −10 V. As of 2004, efficiency upwards of 85% is not uncommon.
DC to DC converters used to be somewhat large for use in devices such as cell phones; however, with the advent of hybrid circuits, they are now available as single package, even surface mount, devices.
Source: CDX Global & Wikipedia - en.wikipedia.org
