The cause of reactive power
Electrical energy flowing through an electricity grid is not just the energy that is converted into light, movement and heat / cooling: the active power. In every electrical installation, elements are installed that require additional electrical energy to maintain their magnetism, such as transformers, ballasts and gas discharge lamps. This additional electrical energy in the grid is called reactive power. Together, the active power and reactive power form the apparent power. The apparent power, therefore, increases due to reactive power. This has consequences for the load on the electrical installation, connection capacity and infrastructure. The reactive power needs to be transported through transformers, cables and lines along with the apparent power. This requires larger numbers of transformers, and/or higher capacity transformers, thicker cables and more copper.
In particular, consumers of large amounts of power suffer from the presence of reactive power in electrical installation. Especially when a large number of motors, electronic speed controllers, welding equipment and/or cooling units are connected. The more of these devices are present or connected, the greater the likelihood of a large amount of reactive power.
Extra reactive power can also be introduced by increased in electronic loads of frequency converters, electronic power supplies and LED lighting. These electronics introduce more and more harmonic currents or harmonic pollution into the installation and the network. These harmonic currents cause the current to distort, resulting in distortion in the voltage.
For more information about the backgrounds and causes of reactive power click here.