Circutor CVMk2 Series Manuel d'utilisateur télécharger pdf (Page 146)

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CVM

CHARACTERISTICS

10.3. OTHER CONCEPTS

10.3.1 UNBALANCE COEFFICIENT (KD)

The unbalance coefcient (Kd) is the ratio between the amplitude of the components in the

direct and inverse sequence.

10.3.1 ASYMMETRY COEFFICIENT (KA)

The asymmetry coefcient (Ka) is the ratio between the amplitude of the components in the

direct and homopolar sequence. The components of the homopolar sequence are zero if there

is not a neutral.

10.3.3 FLICKER

Flicker is considered to be the low frequency disturbances or variations in amplitude of the

voltage between 0.5 and 25 Hz. (f<2,500Hz). Human eye is sensible to modulated frequency

of 8...10 Hz with 0,3 or 0,4% magnitude voltage variations.

The CVMk2 applies the symmetric components method conceived by Fortescue and Stokvis

to make network quality calculations.

This method makes a vector comparison of phasors, taking the phase difference and the

module into consideration. It is used for voltage and current alike.

To indicate the degree of imbalance in a system, two coefcients are used.

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Circutor CVMk2 Series Manuel d'utilisateur Page 146