Compact Flourescent Lamp (CFL) Current Spectral Analysis

A. Jakoef and H.J. Vermeulen (South Africa)


Energy efficiency, lighting, THD, neutral current.


A significant proportion of Industrial and Commercial Energy Efficiency (ICEE) projects conducted as part of Demand Side Management (DSM) interventions involve the retrofit of energy inefficient luminaires with newer, more energy efficient luminaires to reduce the overall energy consumption. In the residential sector, these interventions often target incandescent lamps which are to be replaced by compact fluorescent lamps (CFLs). The formal Measurement and Verification (M&V) of the energy savings impacts of these projects requires that baseline and post-implementation energy consumption profiles are determined for the lamps removed and installed in the intervention. The CFL supply current waveforms exhibit very high degrees of harmonic distortion, with THDs ranging from approximately 110 % to over 250 % over the supply voltage range tested. The measured results for three-phase CFL loads have shown that the CFLs give rise to high zero-sequence, i.e. neutral, current loading. This is a potential cause for concern, especially for underrated networks.

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