Introduction to Alternating Current

A.C. is an electric current that alters its direction and magnitude many times in a second at fixed interval. It reverses its direction 50 or 60 times per second.  All the electric power that is transmitted to your homes and office places are usually A.C. So basically all your commonly used electric appliances like kitchen appliances plug, television, lamps, and vacuum cleaners, etc. make use of altering current, because

– The transformers can be used to increase or decrease the A.C. voltage

– Easy and cheap to convert A.C into D.C, and reversely is not convenient

– A.C. can offer you a high voltage of around 33000 volts, on the other hand, D.C. can offer only 650 volts.

– Production, transmission, and distribution of A.C. supply are more economical as compared to D.C.

– The maintenance and attention required for A.C. motors are much cheaper and easier as they are available in lighter weight and requires much less space than D.C. motors

– High voltages of A.C. can be easily reduced to safer voltages for household power supply

Nevertheless, even direct current (D.C) holds a lot of benefits over A.C. due to which A.C. can never be considered an alternate of D.C. Some of the notes worthy benefits of D.C are

• Arc lamps and Arc welding works better with D.C.
• As compared to Ac transmission line, D.C. transmission can move more power with lesser electricity wastage.
• Higher efficiency of D.C leads to lesser cost while helping renewable energies
• C. works best in operating searchlights and movie projectors.
• C motors have better speed control of speeds of both the directions, thus is definitely a better choice in paper mills and rolling mills.
• Railways, cranes, and lifts make use of D.C. motors as these are much more preferred for traction purposes.
• C usually faces inductive and capacitive losses as with longer direction it’s not possible to keep altering directions, but D.C. eliminates this difficulty and emerges as an idol option in these cases.
• C. is a better choice for moving power to longer distances.

Link of Previous Main Topic:-

• Current Electricity Basic Concepts

Links of Next Electrical Engineering Topics:-

• Generation and Equation of Altering Voltages and Currents
• Alternating Voltage and Current
• Single Phase Circuits
• General Aspects in Single Phase
• Transients Example