Chapter 9Case Studies,Contributors: J. Wikston, E. Gunther, and M. Grady,Tutorial on Harmonics Modeling and Simulation,Case 1,Simulation of the potential harmonic impacts caused by DC motor drives of ski lifts in a ski area,Single Line Diagram,Scenarios,Scenario SKIA.No Corrections. Scenario SKIB.30 phase shifting transformers added at Apollo and BigBoss ASDs. Scenario SKIC.Case SKIB, plus 1800 kVAr of filters,SKIA, Voltage Waveform and Spectrum at Bus #1, Substation 12.5 kV (THDV = 12.2,SKIB, Voltage Waveform and Spectrum at Bus #6, Base (THDV = 8.7,SKIC, Voltage Waveform and Spectrum at Bus #6, Base (THDV = 2.7,Case 2,Harmonics and interharmonics, the filter design, and design verification measurements associated with an industrial load,Introduction,The load and compensation Measurements Filter design Performance measurements,Load and Compensation,6 pulse load Characteristic harmonic orders are n*p +/- 1 Initial design 5th and 7th on MV bus,Measurements - Voltage Distortion,Measurements 200 ms window,Measurements - Interharmonics,Filter Design,Type of filter Location of filter,Filter Types,Filter Location,Utility bus Secondary of customers step-down Fault level reduced to Utility bus impedance 100% variation Secondary of customer step-down 50,Performance Measurements,Case 3,Analysis of harmonic impacts of variable frequency drives to the system,SuperHarm model one-line diagram,Predicted voltage waveform distortion without filters,Predicted voltage waveform distortion at Bus I with power factor correction capacitors