Harmonic distortion an ‘increasing problem’, says power analysis company
According to Outram, harmonic distortion is becoming a significant problem due to the number of mains-connected devices using high efficiency switching power supplies or inverter-type power sources, where power is supplied from renewable sources that require DC to AC conversion.
Switching power supplies, which are used in products such as variable frequency motor drives, IT equipment, home entertainment systems and LED lighting, tend to draw power through current spikes at the peak of the mains cycle. Low energy compact fluorescent light bulbs (CFLs) also exhibit the same behaviour.
This causes harmonic distortion, as can the DC to AC power conversion increasingly used in renewable energy sources. Outram is now offering a firmware upgrade to its PM700 power analysers, which analyses the phase difference between the harmonic voltage and current up to what it claims are the industry’s highest sampling rates; recording up to the 50th and 120th harmonic.
“Visibility is critical to help engineers solve the increasing problem of harmonic distortion of the mains waveform,” said John Outram, Managing Director of Outram Research. “By providing information on the phase difference between current and voltage up to the 120th harmonic we help engineers to identify and resolve problems more quickly and efficiently.”