Terhelésindex

Terhelésindex is a term used in the context of electrical engineering and power systems to describe the ratio of the power drawn by a load to the apparent power supplied to it. It is a dimensionless quantity and is also known as the power factor. The terhelésindex is a measure of how effectively electrical power is being used by a load.

A terhelésindex of 1 indicates that the load is purely resistive, meaning all the supplied power is converted into useful work, such as heat or light. In such cases, the real power (measured in watts) is equal to the apparent power (measured in volt-amperes). However, many electrical loads, such as motors and transformers, are inductive or capacitive. These loads introduce a phase difference between the voltage and current, leading to a terhelésindex less than 1.

When the terhelésindex is less than 1, a portion of the supplied apparent power is reactive power, which oscillates between the source and the load without doing any net work. This reactive power increases the current flowing through the system, leading to higher losses in the transmission lines and requiring larger transformers and generators. Therefore, maintaining a high terhelésindex is desirable for efficient power distribution. Power factor correction techniques, such as adding capacitors to inductive loads, are often employed to improve the terhelésindex and reduce energy waste.