Power is one of the most important parameters defining the properties of electrical circuits. The basic magnitude used for financial settlements between the supplier and the consumer is electric energy which is the power multiplied by time.

There are a few different power types that can be found in power quality measurement

  • active power. Designated as P. Measurement unit is watts W,
  • reactive power. Designated as Q.  Measurement unit is VAR,
  • apparent power. Designated as S.  Measurement unit is VA.

These three types of power are the most known, but there are also other types.

At school we are taught that these three power types make up a so-called power triangle.  However, referring to the power triangle is only correct for systems with sinusoidal voltage and current waveforms.