Whenever any type of ore deposit is developed, it comes with significant risks, such as uncertain reserves, harsh climate conditions, and other uncontrollable factors. To manage these risks effectively, companies need to quickly adapt to changing conditions. This paper presents a method for evaluating risks using a simulation model. The main objective is to identify factors of operational risk and determine the project parameters that have the greatest impact on the probability of a risk event. The method includes the classification of operational risks based on the way they arise; the creation of a risk decomposition matrix dividing risks by production tasks; and the construction of a mathematical model using the identified risk factors. The method was tested by developing a simulation model of an underground mine conveyor network in Anylogic (8.9.2) software. A simulation experiment showed that conveyor shutdowns could result in an 11.23% reduction in annual revenue. Based on the results, recommendations were made on how these risks can be reduced and on the need to implement a transport system to increase resilience.

he purpose of the work is to analyze the aggregates of complexes for the extraction of marine minerals. In particular, the variants of complexes, their advantages and disadvantages are considered. The complex is analyzed, which uses robotic pickers/reclaimers of the walking type to perform mining operations of ferromanganese nodules (FMN) or cobalt-bearing manganese crusts (CMC). Results. The variants of complexes for mining of bottom deposits are analyzed, advantages and disadvantages of different variants are indicated. The device for collecting minerals on the bottom, developed in SPMU, is described, laboratory studies of the model of such a device are considered, the main parameters are presented, the dependence of productivity on the size and time of operations of the cycle of work is indicated. It is determined that for minimal impact on the seabed biota it is necessary to use walking submersibles with an actuator for extraction in the form of rarefaction chambers or a grapple with an impactor (depending on the type of solid minerals). It is shown that the productivity of the walking underwater vehicle varies with the diameter of the rarefaction chamber plates: the optimum plate diameter is 1.5 m. Experimental study of hydrodynamic resistance of “foot” models with different midships cross-section has been carried out. According to the experimental results, the conclusion about the preferred design of the “foot” was made: the cross-section should be a streamlined shape with the smallest drag coefficient cx and have a continuous surface without holes. Experimental studies of tine models movement in water have shown that it is reasonable to use as tine parts the structures without holes, streamlined ellipsoidal shape. Calculations of productivity of mining units when using rope hoisting from the bottom to the ship have shown the necessity of using four or more hoisting devices for realization of the required annual productivity of more than 1 million tons per year. The stages of creating a workable extraction unit including a vessel, vertical lifting device and a system of deep-water collectors require very significant material and monetary costs, so they should be carried out in accordance with the R&D plan and tasks of the relevant ministry and agency and require coordination of efforts of investors, scientists and machine builders.

The article considers the most modern and most informative methods for diagnosing faults in squirrel-cage induction motors with a short-circuited rotor. The methods are based on the evaluation of vibrations and electrical parameters, as well as coordinates during operation and are normalized when powered from a sinusoidal voltage with frequency of 50 Hz. The main advantages and disadvantages of these methods, as well as the main indicators characterizing the general technical condition of the electric motor, are described. The application of these methods when powered from a non-sinusoidal voltage is impossible due to the complex harmonic composition of current and voltage. The consequence of this composition are the ripple moment and additional power loss. The interaction of the harmonics of the inverter and subharmonics, caused by faults, leads to the occurrence of a resonance phenomenon, and therefore to a decrease in the stability of the electric drive.