Actually, charging the car battery is the responsibility of the engine. The car engine works to drive the generator, then the generator completes the car battery charging cycle. The car's generator generates electricity by driving the generator through a belt while the engine is constantly running. Excess electricity will be stored in the battery.
Usually, when the engine does not start, we can use some energy-consuming equipment in the car, such as temporary use of audio equipment, lighting, anti-theft uninterrupted power supply , etc. The systems are all supplemented by batteries. However, this operation should not be carried out for too long, as it will consume all the battery energy, make it difficult to restart the engine and make it impossible to complete the energy supply cycle. You must donatec charge the car battery at that time. Once the battery is exhausted, it cannot be recharged with current. It needs to be charged with a charger for several hours to fully charge it, as the plates were damaged when the battery runs out and need to be recharged. Go out for more than a week, you need to disconnect the battery. Open the negative terminal of the battery.
Before starting the vehicle, check the appearance of the car battery to ensure that the battery surface is intact, has no cracks, and has no obvious signs of battery leakage. battery acid. If the car battery has any of the above damages, do not start the car to avoid an accident. Turn off the engine, remove the used battery from the vehicle and charge it with a battery charger. Find a ventilated, cool place. If it is a maintenance-free battery, there is no need to openlid. Otherwise, you need to open the breathable battery cover. Some lids are screwed on, just unscrew them. in the opposite direction, and some require a screwdriver to open it, depending on the situation; then use the red clamp of the charger to clamp the positive battery terminal marked with a plus sign, and the black clamp to clamp the negative battery terminal marked with a plus sign. minus sign.
Charge the used battery slowly when charging. Select 12 volt power and select low gear to slowly charge the battery and turn on the switch to charge the battery. the time should not exceed 12 hours.
The car charging system consists of a generator, battery, voltage regulator, charging indicator light and associated wires. The connection relationship between them is as shown below. Each component works and. the operating principles of the ssystem are as follows.
1. Generator: Generator is the main power supply for automobile electrical equipment. During normal car operation, the alternator powers other electrical equipment except the starter and charges the battery. That is to say, when the engine is running normally, almost all of the car's electrical energy is supplied by the generator; when there is power left, the generator will charge the battery; Generally, the power of a car generator is 0.8 to 1.5 kilowatts, which can meet the power demand of the car in most cases. When energy production is insufficient, the battery supplements it. For some small displacement engines, when the generator generates a large amount of electricity and the load is high, the engine vibrates due to the increased load. At this time, the motor automatically increases the speed toimprove engine power.
Most generators used in automobiles are three-intersection silicon rectifiers. Current generator, which uses silicon diodes as rectifiers to convert alternating current into direct current. Its main structure is composed of rotor, stator, brush and slip ring mechanism, three-phase rectifier bridge, bearings, fans and front and rear covers. The rotor is used to generate a magnetic field, the stator is used to generate current. , and the rectifier converts the three-phase current. The alternating current is converted into a pulsating direct voltage. The power generated by the generator increases as the engine speed increases.
2. Battery: Battery is what we commonly call battery. This is the largest electrical equipment in the car. Its main function is to power the starter, theignition system and other major electrical equipment. the engine starts; when the engine does not run or runs at low speed, it powers various electrical equipment when there is too much electrical equipment and the power consumption exceeds the power supply capacity of the generator, the battery assists the generator; to power various electrical equipment; In addition, the battery also has the function of stabilizing the voltage of the power system. It is equivalent to a large capacitor and can absorb instantaneous surges in the circuit to protect electrical equipment.
Many people think that the battery is the car's main source of power. In fact, this is not the case. The generator is the real source of power for the car. When the engine is running normally, the generator output voltage is higher than the car battery voltage. The generator powers alls electrical equipment (except the starter) and charges the battery at the same time. internal storage when the engine starts. Electrical energy operates the starter and usually exists in the form of an electrical device.
3. Voltage Regulator: The voltage regulator is used to adjust the generator output voltage to maintain the generator output voltage between 13.8 and 14.4 volts. Since the generator output voltage increases with increasing engine speed, if the engine speed is too high, the generator output voltage will be too high, which will burn out the car's electrical system and some electronic components of the car. precision. With a voltage regulator, these problems can be avoided. Car voltage regulators are now all electronic, most are built inside the generator and only a few are external. The vast majority of generator failuresThese are caused by a faulty voltage regulator.
4. Charge Indicator System: The charge indication system mainly refers to the voltmeter or charge indicator light on the dashboard. They are used to indicate whether the operating condition of the generator is normal. If the charging light turns on or the voltmeter indicator is lower than 24V while the car is driving, it means the generator is not charging or the charging capacity is too low and the charging system needs to be repaired.
The working principle of the car charging system is: when we turn on the ignition switch, the battery provides excitation current to the generator rotor, and the rotor generates a field magnetic, then the motor starts; , causing the generator to operate, and the stator winding cuts the rotor winding. Magnetic field lines generate alternating current triphase, which is converted into direct current after rectification and output of silicon at that time, because the speed of the generator is low, that is; The excitation current is supplied by the battery. This situation is called "other excitation", then as the generator speed becomes higher and higher, the power output becomes larger and larger, and the rotor winding current is supplied by the generated current by the battery. the generator itself. This situation is called “self-arousal.”
When the engine is operating normally, the generator also works at high speed with the engine, emitting electrical energy for use by the car's electrical equipment, and the excess electrical energy is used to charge the battery. When the battery is fully charged, the voltage regulator cuts off the excitation current to the rotor and the generator stops producing electricity; When the battery voltage drops to a certain value, the voltage regulator reconnects the excitation current and the generator starts producing electricity again. This process is repeated again and again, which can not only ensure the normal operation of the car's electrical equipment, but also keep the battery in a fully charged state. In order to ensure that the car can produce electricity at low speed, the speed of the generator is generally 2.5-3 times the speed of the engine, so even if the engine is idling, the generator can produce electricity Normally.
Common faults in automotive charging systems include no charge, overcharge and undercharge. The causes of faults are only two types: poor line contact and failure of the generator itself. Generally speaking, today's generators are highly integrated and cannotcannot be dismantled and repaired under normal circumstances, and can only be replaced as a whole. When the car charging system is used, it is not allowed to use the instant grounding (grounding) method of the generator output end (fire test method) to determine whether the generator is producing electricity, nor remove the battery and other main electrical equipment when the generator is running at high speed, to avoid power surges caused by the breakdown of precision electronic components. During daily maintenance, it is necessary to frequently check the connection between the generator and the battery to ensure that the connection is firm and reliable and that the joints are free of rust. Additionally, the generator belt tension should also be checked. frequently. If the belt is too loose, the generator speed will be reduced. If it is too weak,energy production will be insufficient. If the belt is too tight, it will easily damage the generator belt and bearings.