Alternator rectifier, the name reminds of physics book, a word out of the chapter describing about electricity. Simply thought, what comes to people’s mind when they see this word? Answer – something that has to do with alternation and rectification. Therefore, the basic point is – alternator rectifier is an electronic device whose main task is alternation and rectification. The details about this device are discussed below.
The first part of this phrase, Alternator, is an electromechanical device that alters or transforms mechanical energy to electrical energy. In simple words, it produces electricity by burning the fuel (oil, gas, etc.) or by physical movements of magnetic fields etc. The electricity it yields is AC (alternating current), which is the usual form electric power transported and delivered through wires and used in everyday life. Examples of alternator could start from AC electrical generator to steam turbine driven alternators in power stations called turbo-alternators etc. However, the most common use of this word is done for referring to small rotating machines driven by automotive and other internal combustion engines.
Rectifiers are simple electrical components which converts AC current to DC, in physics which is known via the term rectification. The basic idea about alternative current (AC) has already been given. Now, the DC current is the flow of current produced by such sources as thermocouples, batteries and other solar cells and commuter-type electric machines. In AC current, the movement of these specific electric charges reverses direction in a constant time interval. DC current however sees the flow of electrons in a mono directional manner. So, the rectifier takes in the electronic charges moving like sine- curve and transforms them as such that they move in one direction. Rectifiers may be made of vacuum tube diodes, mercury arc valves, or solid-state diodes.
Derived from these two definitions of alternators and rectifiers, it can be said that Alternator Rectifier transforms mechanical energy into AC current and then that into DC.
The following diagram will help to make things more understandable:
- Input: Mechanical energy (fuel, movement of magnetic field, steam etc.)
- Processor: Alternator Rectifier (produces alternating current, then converts into direct current)
- Output: Direct Current (DC)
The usual alternator rectifier refers to ones that are used in the automobiles. The alternator rectifier is an essential component of an automobile’s charging system. It is one of the three major components of the charging system in an automobile. The other two are the Battery and the Regulator.
Alternator rectifiers are used in motor vehicles to produce direct current for recharging the battery and for developing electricity to power all other electrical components when the engine is running. The basic function of the alternator is to generate the electricity required to start and run the automobile.
Alternator rectifiers work together with the battery to supply power when the vehicle is running. The alternator actually creates AC voltage. The rectifier inside it then converts the AC voltage into DC. Therefore, the final output of an alternator is direct current, which makes its way to the battery and the electrical loads.
The alternator rectifier is one complex electronic device. It is comprised of five basic parts, these are:
- Rotors: The job of this rotor is to produce a magnetic field.
- Stator: Voltage is induced into the stator.
- A diode assembly called the rectifier bridge: The rectifier is responsible for the conversion of AC stator voltage into DC output.
- A control device called the voltage regulator: This regulator examines battery voltage and directs flow of current to the rotor assembly
- Two internal fans to promote air circulation: The fan pulls air in through vents at the rear of the alternator to cool the diodes.
As it is seen, the alternator rectifier is very important for the automobile. Therefore, proper maintenance for this should be done. Before any long trip, it is advised to check the automobile’s charging system find out whether the alternator is operating properly and generating the correct amount of current and voltage or not.
Problems in alternator rectifiers can result in low battery, reduced light operation, repeat voltage regulator failures, erratic engine operation etc. To avoid all these troubles, qualified personnel should check out the automobiles’ charging system regularly. With proper care and maintenance, an average alternator is expected to run for 75-100 thousand miles.