Carlos Izquierdo Mitchell

Power factor correction and harmonic mitigation in industry

Power factor correction in industrial facilities has become a problem nowadays because of the widespread use of power electronic equipment. Frequently, single tuned filters must replace capacitors used to increase the power factor in order to avoid resonances. This paper presents an analytical technique used to improve power factor and reduce harmonics. An orthogonal decomposition of currents in three-phase system is applied in order to compute the optimum power factor compensator for each individual problem.

Reference current errors of instantaneous pq-based methods for active filters

The reference current errors of instantaneous pq-based methods for active filters are analyzed in this paper. First, the error function in steady-state conditions is derived and a numerical harmonic analysis is performed. A theoretical harmonic analysis is developed to carry out the underlying reasons that causes the error harmonics due to the singularity of the harmonic spectrum. Finally, some examples of application are reported.

Electrical maps of induction machines

The study of circular maps of induction machines is one of the classical subjects dealt with in literature about electrical machines and it is fairly interesting from a didactical point of view as well as from its practical applications. This paper presents a new and general method that allows for, among other things, the analytical way of obtaining center coordinates and the radius of any of the geometrical maps (impedance, admittance, current, voltage, and power) of induction machines. To reach this goal, a two-port model associated to any of the equivalent induction machines is used.

Optimal split-phase configurations

Phase split is a well known procedure to reduce the magnetic field level generated by power lines. In this paper the more efficient split-phase configurations are obtained by means of different magnetic field formulations based on the current dipole and quadripole decomposition of the line. The performance of these configurations is also analysed in relation with other aspects: surge impedance loading, electric field, electromagnetic and electrostatic unbalance and corona effect.