G5-5 Harmonic Distortion and how it also relates to G97 Engineering Recommendations.

Engineering Recommendation G5 Issue 5 2020 Harmonic voltage distortion and the connection of harmonic sources, and/or resonant plant to transmission systems and distribution networks in the United Kingdom.

The new G5-5 recommendations on harmonic disturbance are a significant change to the previous G5-4. Importantly, this is a site standard rather than a product standard. This means system integrators and end-users must ensure compliance or risk withdrawal of supply by their utility company.

In a power system, most equipment not drawing current in a linear way will create harmonics. This category includes variable speed drives and of course DC to AC inverters. Harmonic disturbance changes the current and voltage waveforms causing possible disruption to electronic controllers and overheating in switchgear. In extreme cases, it can also result in the failure of connected equipment.

Moreover, the harmonic disruption can radiate from a company’s location to other nearby sites that share the power grid. This effect may need special consideration in the design of an electric system to serve non-linear loads.

This online training course will give anyone working with DNOs (Distribution Network Operators) a good understanding of what they want and expect from any equipment, you are trying to get connectivity for on their part of the National Grid.