Improving power quality in mining industries with a three-level active front end

Abstract

This paper deals with the power quality improvements that can be achieved in mining industries by the employment of a high power active front end. A three-level neutral-point-clamped rectifier with low harmonic distortion and high power factor is chosen alternatively to diode rectifiers. A constraint on this class of converters is its lower switching frequency that results in low order harmonics. This is often solved employing passive filters. In this paper an appropriate choice of modulator and filter topology leads to significant simplifications on the filter design and reduces both weight and cost of its elements. The Selective Harmonic Elimination is presented and though it is generally considered as a steady-state technique it was designed to work in transient conditions within a closed loop current control. The system is submitted to tests in order to assess its operational performance through simulation results. Experimental data from a prototype is also presented.

Power Quality Issues of Distorted and Weak Distribution Networks in Mining Industry: A Review

“…Similarly, a modified version of a SHEPWM technique for low power, high switching frequency 2-level converters has been proposed in [41] and further been implemented in high-power low switching frequency 3-level converters. In [43], a SHEPWM technique along with an LCL filter has been presented to address the power quality issues for three-level AFE Medium Voltage Drives (MVDs) used in mining industry. The harmonic analysis has shown that the low switching frequency technique in SHEPWM has a better harmonic profile compared to Phase Disposition PWM and can reduce switching loss and improve efficiency.…”

Badania nad zabezpieczeniem upływowym prądu elektrycznego w celu poprawy bezpieczeństwa elektrycznego w górnictwie podziemnym w Wietnamie

“…With the increasing degree of mechanization, power electronic converters are gradually being used at all stages of underground mining. They are responsible for regulating the working process of the motor or improving the power quality of the mine power network [2][3][4].…”

Control Strategy of 1 kV Hybrid Active Power Filter for Mining Applications

“…Furthermore, it should reduce the number of interruptions and disturbances in the operation of atmosphere parameter monitoring systems, thus increasing the level of safety of mine workers [53,54]. The application of HAPF yields financial benefits due to lowering power losses and slowing down the aging effects of appliances e.g., motor drives [55][56][57][58].…”