AC (alternating current)

Definition

Alternating current (AC) is a form of electric current that periodically changes its direction and amplitude. Unlike direct current (DC), which flows constantly in one direction, alternating current changes its direction several times per second - in the grid in most European countries 50 times (50Hz).

More information (Wikipedia)

Operating principle

Alternating current is generated by generators that use a rotating magnetic field to move electric charges back and forth in a conductor. This alternating movement produces the flow of current. The advantage of alternating current is that it can be easily transformed to increase or decrease the voltage. This is very useful for transporting electrical energy over long distances and in residential buildings, as losses caused by resistance in the wires can be reduced. Although the current of alternating current fluctuates from zero to the maximum value, the so-called effective value, an average, can be used to calculate power and energy.

Practical examples

• The power supply in most households and businesses operates with alternating current.
• Alternating current is used in high-voltage networks for the transmission of electricity over long distances.
• Many everyday devices such as kitchen mixers, vacuum cleaners, and hair dryers use alternating current.

Advantages

• Alternating current can be easily transformed to increase or decrease the voltage.
• Alternating current can be easily transmitted over long distances.
• Alternating current is used for most applications in households and commercial areas.
• Alternating current machines are robust and require little maintenance.
• Alternating current is safer to handle than direct current.
• Alternating current is easier to generate than direct current.
• Alternating current devices are generally more affordable.
• Optimal use of existing infrastructure.

challenges

• Alternating current can cause interference and increased noise when used near electronics.
• Electromagnetic emissions caused by alternating current can be harmful.
• Alternating current can cause skin and bone injuries.
• AC motors have lower torque at low speeds.
• Alternating current has capacitance and inductance effects that must be considered during transmission.
• Certain devices operate more efficiently with direct current.
• The transition from AC to DC devices can be expensive.
• Alternating current requires specialized protection systems for high voltages.

Best Practices

• Proper protection is required for safe use.
• Transformers should be regularly maintained to ensure efficiency and safety.
• When installing cables, the appropriate cross-section must always be chosen.
• When selecting devices and motor systems, attention should be paid to a high efficiency.
• Always observe all regulations and standards regarding installation, operation, and maintenance.
• For emergencies, there should always be a backup power supply available.
• Regular inspections of electrical installations by qualified personnel are necessary.
• The use of surge protection is recommended to prevent damage to electronic devices.

Conclusion

Alternating current is the key technology for electrical power supply and enables the safe and efficient operation of most modern electrical devices and systems. Despite certain challenges and risks, including electromagnetic interference and potential health effects, the advantages of alternating current far outweigh them. This is especially true for its ability to be easily transported over long distances and its widespread practical application. Through correct use and adherence to safety instructions, alternating current can be used safely and effectively.