Soft Starter Model For Harmonics Analysis

Hello

I'm looking for references to modelize soft-starter for an harmonics analysis. The question about negligeable effets of soft-stater is irrevelent. The utility provider demand proofs of it for the particular studied installation.

Thank you

Motor Starting Study With Industry's Typical Data

Hello members of LMPforum

I need to validate a modelization of a futur industrial distribution network, especialy typical torque curves, Wk2, moment of inertia, equivalent circuit and soft-starter settings. I would like to know if you could help me to find what I need.

I'm working on mining development project. There will be 575 V motors ranging from 15 HP to 425 HP. Most of them are started by soft-starters, two (2) or three (3) will be DOL started and two (2) are controled by VFD. The applications are compressor, fans, pumps, rock crusher and jumbo drill.

I have to study flickering voltage perturbation amplitude to verify that it respects the flickering limits (being below) of the energy provider (Hydro-Québec, refered as HQ in the rest of the text).

In my case, the starting of the motor are what will created those perturbations. So I need to determined the inrush current (or inrush power) that occured when I start each of the motors.

To date, I evaluate the flickering level once with inrush currents at 200% for every soft-starting motor and once with inrush currents at 400%. With the 200% FLC starting, it's barely below the limits. With the 400% FLC, it's quite over the limits.

The calculation method is simplified. I would be able to refined the inrush current level for each motor using my power system analysis software, CYME PSAF. The objective is to have a model that would be nearer to the projected system.

However, the client have not yet purchased or received all the equipments. Also, most are second hand equipment. So the data for each motor and load are not available and I have to work with typical data.

Right now, I have hard time to find typical data to modelize adequatly the system in my study software. Particularly the torque curves, the Wk2,moment of inertia, soft-staters settings and the equivalent circuit of the motors (i'm quite confused with the PSAF tools for that last)

Thank you