CRT-100.29 The Role of Index of Microcirculatory Resistance in Left Anterior Descending Artery ST Segment Elevation Myocardial Infarction Patients With Thrombolysis in Myocardial Infarction Myocardial Perfusion Grade 3 After Primary Percutaneous Coronary Intervention

This chapter discusses single- and three-phase transformers used in distribution and power systems for harmonic suppression, such as dedicated isolation transformers, delta/zigzag, and delta/wye three-phase transformers. The relationship between harmonic flux and voltage is explained. Harmonic losses and the associated derating of transformers are predicted and confirmed by loss and temperature measurements. Linear models are extended to nonlinear models. Equipment grounding and lightning protection and propagation are addressed. Ferroresonance must be avoided when designing underground AC transmission lines. The effects of geomagnetic disturbances caused by solar flares in power systems built on igneous rock formations (such as the Rocky Mountains) are prevented with special grounding techniques and the employment of specially designed three-phase transformers. Direct and indirect transformer loss circuits with associated measuring techniques are presented, resulting in improved and more accurate derating measurements. Time-dependent and frequency domain simulation techniques are addressed.