Analysis of supraharmonics in a three-phase frame

Interaction in the supraharmonic range of 1-phi device connected in 1-phi or 3-phi installations will differ according to the design of the installation. Power factor corrected devices employing switched mode power supplies produce supraharmonics in the range 2-150 kHz. The impact of e.g. voltage unbalance, load unbalance and conductor crosstalk on supraharmonics from these devices connected in a 3-phi installation are still somewhat unknown. The paper aims to show with measurements and mathematical models the impact of voltage unbalance, load unbalance, and conductor crosstalk on supraharmonics. The impact of voltage unbalance for constant power loads was seen to increase the emission of supraharmonics. Two new terms induced primary and induced secondary emission showing the impact of conductor crosstalk have been introduced. The induced primary emission leads to an increase in the self-emission of the device. The induced secondary emission on the other hand influences the propagation of the emission. The impact of the voltage unbalance, load unbalance, and conductor crosstalk on the addition of supraharmonics emission in the neutral conductor is shown.