Tool for the Assessment of the Savings in the Cable Acquisition When Employing DC Transmission in Long Distance Drives

Throughout different stages of the mining processes, alternating current (AC) motors powered by pulse width modulation (PWM) converters are employed, typically connected by extensive cable lengths. While these drives bring forth significant advantages, they also give rise to challenges associated with high-frequency problems, which, in turn, reduce the operational lifespan of the system components. Off-the-shelf solutions, involving the incorporation of passive filters, tend to adversely affect both the cost and efficiency of the system, justifying research for new alternatives. A recent proposal suggests a distinctive approach, wherein the frequency converter is divided into its rectifier and inverter units. The former is situated in its original location, while the latter is positioned close to the load. Consequently, the drive system operates with direct current (DC) for electric power transmission. This innovative topology not only eliminates the high-frequency problems but also substantially enhances efficiency while reducing costs of the transmission. Prior research has demonstrated the potential of this alternative drive topology, particularly through case studies in low- and medium-voltage systems within mining plants. In this paper, the economic and energy efficiency potentials of such DC transmission drives regarding the power transmission are examined using reference graphs that offer insights beyond conventional case studies. These graphs represent decision-making tools, allowing for a quick and accessible assessment of the economic viability of the alternative topology for a wide range of powers and drive distances. The main aspects related to the methodology, along with relevant technical discussions, are addressed.