The generator is driven by a belt from the crankshaft of the engine.
The generator is a three-phase synchronous electric machine with electromagnetic excitation. A diode rectifier is built into the generator to convert AC to DC. The output voltage is regulated by a built-in regulator. The generator is grounded by weight.
When the generator is running, the electric current flowing through the field winding creates a magnetic flux around the rotor poles. When the rotor rotates, its magnetic poles periodically change under each stator tooth, as a result, the magnetic flux passing through the teeth continuously changes in magnitude and voltage. This variable magnetic flux creates an electromotive force in the stator winding (EMF). The wedge-shaped shape of the pole pieces of the rotor is selected in such a way that it makes it possible to obtain an EMF curve close to sinusoidal.
At a high rotor speed, when the generator output voltage begins to exceed 13.6 ÷ 14.6 V, the voltage regulator is locked, and the current through the excitation winding does not pass. When the voltage drops, the regulator opens again, allowing free flow of current through the field winding. The higher the rotor speed, the longer the regulator remains locked and, accordingly, the voltage at the generator output decreases more. The process of locking and unlocking the regulator occurs at a high frequency, so the output fluctuations remain almost imperceptible and the generator voltage can be considered constant, maintained at a level 14.4 V.
The charging system does not require periodic maintenance, however, the condition of the alternator drive belt, battery and its wiring should be checked and replaced on a regular basis in accordance with the maintenance schedule (see Sections Battery check and care and Checking the condition of the accessory drive belt Chapters Vehicle settings and routine maintenance).
When you turn on the ignition on the instrument cluster, the K / L of the charge should light up for a short time (see chapter Controls and methods of operation). If the lamp does not turn off after starting the engine or lights up during its operation, check the condition of the charging system components. Failure to activate the lamp when the ignition is turned on indicates its failure, damage to the corresponding electrical wiring, or a malfunction of the generator (including broken drive belt).
Generator Maintenance Safety Precautions
- Do not disconnect the battery or voltage regulator while the engine is running;
- Do not ground the generator excitation terminal or the cable attached to it;
- Do not confuse the order of connecting the voltage regulator wiring;
- Remember that the inclusion of a voltage regulator closed to ground leads to its instantaneous failure;
- Never remove the generator with the battery connected;
- Do not confuse the polarity of the battery connection;
- Never use voltage meters or test lamps connected to a household network when checking on-board electrical equipment (110/220 V);
- When checking the condition of the diodes, do not apply a voltage of more than 12 V to them and do not use megohmmeters, which also have a high output voltage - breakdown of the diodes will lead to a short circuit. Remember that when checking the insulation of the electrical wiring with a megohmmeter, it is necessary to disconnect all electrical wiring from the generator;
- When charging the battery without removing it from the vehicle, make sure that both wires are disconnected from it. Do not confuse the polarity of the charger connection;
- Before carrying out any electric welding work on the car, do not forget to disconnect the electrical wiring from the generator and battery;
- Any checks of circuits and on-board wiring assemblies should be carried out with the engine off and the battery disconnected;
- Remember that reversing the polarity of any connections carries the risk of permanent damage to the rectifier and generator voltage regulator.