The prospects for implementing battery-powered dump trucks at open-pit mining enterprises are considered. Main attention is on the problem of charging infrastructure for adopting the unmanned production concept. The suggestion is to use wireless charging stations to join charging with particular technological operations, thereby reducing battery capacity and increasing the utilization rate of electric vehicles. To determine effective charging infrastructure solutions, it is necessary to evaluate the interaction between the dump truck and charging stations. The research aims to develop a model reflecting the power flows between the charging infrastructure and the dump truck battery while an operational process is being executed. The model takes into account the work cycle parameters, dump truck parameters with powertrain options providing energy recovery at braking, and charging infrastructure parameters in three options: one stationary charging station located outside the operating routes designed for the simultaneous charging of several dump trucks (option A); stationary charging stations for one dump truck located at loading points (option B); and a dynamic charging station that charges in motion (option C). The method for determining the power of a single wireless charging station is proposed, along with a related method for determining battery capacity. When establishing capacity, the parameters of the charge-discharge cycle and the charging current ratio are considered. The described model is implemented in MATLAB Simulink using m-files for processing satellite data of route parameters from geographic information systems, as well as elements of the Stateflow and Simscape Electrical libraries. The capabilities of the model were demonstrated on the example of the Lebedinsky GOK, with the BelAZ-7558E selected as a battery-powered dump truck. In the example considered, the total capacity of the wireless charging infrastructure for options A, B, and C was 10.6; 6.3, and 13.5 MW, with option B providing the highest value of the battery average state of charge of 0.65 p.u., with the lowest specific power demand per dump truck of 2.4 MW·h. The simulation results allow us to determine various operating factors of the system, evaluate the power compliance of system elements, compare wireless charging infrastructure options, and make informed design decisions.
The electric vehicles development has a high potential for energy saving: an energy-saving traffic control can reduce energy resource consumption, and integration with the power grid provides the ability of daily load pattern adjustment. These features are also relevant for underground mining. The critical element of vehicle-to-grid integration is the charging infrastructure, where wireless charging is promising to develop. The implementation of such systems in underground mining is associated with energy efficiency issues and explosion safety. The article discusses the development and research of a wireless charging system for mining electric locomotive A-5.5-600-U5. The analytic hierarchy process is used for justification of the circuitry and design solution by a comparison of different technical solutions based on energy efficiency and safety criteria. A complex computer model of the wireless charging system has been developed that gives the transients in the electrical circuit of a wireless charging system and the high-frequency field density distribution near the transmitting and receiving coils in a 3D setting. An approach to ignition risk evaluation based on the analysis of high-frequency field density in the charging area between the coils of the wireless charging system is proposed. The approach using a complex computer model is applied to the developed system. The study showed that the wireless charging system for mining electric locomotives operating in the gaseous-and-dusty mine is technically feasible and there are designs in which it is explosion safe.