The issue of movement stability remains highly relevant considering increasing vehicle speeds. The evaluation of vehicle stability parameters and the modeling of specific movement modes is a complex task, as no universal evaluation criteria have been established. The main task in modeling car stability is an integrated assessment of the vehicle’s road interactions and identification of relationships. The main system affecting the vehicle’s road interaction is the suspension of the vehicle. Vehicle suspension is required to provide constant wheel to road surface contact, thus creating the preconditions for stability of vehicle movement. At the same time, it must provide the maximum possible body insulation against the effect of unevennesses on the road surface. Combining the two marginal prerequisites is challenging, and the issue has not been definitively solved to this day. Inaccurate alignment of the suspension and damping characteristics of the vehicle suspension impairs the stability of the vehicle, and passengers feel discomfort due to increased vibrations of the vehicle body. As a result, the driving speed is artificially restricted, the durability of the vehicle body is reduced, and the transported cargo is affected. In the study, analytical computational and experimental research methods were used. Specialized vehicle-road interaction assessment programs were developed for theoretical investigation. The methodology developed for assessing vehicle movement stability may be used for the following purposes: design and improvement of vehicle suspension and other mechanisms that determine vehicle stability; analysis of road spans assigned with characteristic vehicle movement settings; road accident situation analysis; design of road structures and establishment of certain operational restrictions on the road structures. A vehicle suspension test bench that included original structure mechanisms that simulate the effect of the road surface was designed and manufactured to test the results of theoretical calculations describing the work of the vehicle suspension and to study various suspension parameters. Experimental investigations were carried out by examining the vibrations of vehicle suspension elements caused by unevenness on the road surface.

The dynamic process of the railway track–rolling stock interaction is characterized by time-dependent dynamics that are determined by both the varying characteristics of the interaction objects and the varying climatic conditions. This study investigated the effect of different groups of influence on the dynamic process, with a view towards the reduction of the cases of randomness during the registration of the process in experiments and an expansion of the understanding of the processes happening during the assessment of the registered data. The static nature of the rolling stock has been demonstrated to be not uniform and to influence the scattering of dynamic values under the variation of vertical and horizontal forces due to the characteristics of a rolling stock. The position of the rolling stock truck relative to the track axis during the movement of the rolling stock has been shown to enhance static non-uniformity. The results of the longitudinal force measurements under the three-point and Schlumpf methods have suggested that it is necessary to investigate the process of rail warping under the action of the rolling stock wheels. To enhance the output of the experiments, it is proposed to consider not only the stiffness of the basis of the oscillatory processes that imitate the physical process of oscillation of the system elements by means of the oscillation amplitude, but also the time of response to the oscillation process by using and assessing the triggering time rather than the frequencies of the oscillation processes.

This paper deals with the analysis of the operating conditions of traction drives of the electric locomotives with asynchronous traction motors. The process of change of the catenary system voltage was found to have a stochastic character. The method of current controller synthesis based on the Wiener–Hopf equation was proposed to enable efficient performance of the traction drive control system under the condition of the stochastic nature of the catenary system voltage and the presence of interferences, when measuring the stator current values of the tractor motor. Performance simulation of the proposed current controller and the current controller used in the existing vector control systems of the traction drives used in the electric locomotives was implemented. The results of the performance simulation of the proposed current controller were compared with the performance of the current controller in existing vector control systems of the traction drives. The results are applicable to the design of vector control systems of traction drives in electric locomotives and to the study of the influence of performance of electric traction drives in electric locomotives on the quality indicators of the power supplied by the traction power supply system under the actual operating conditions of the locomotive.

This article presents an analysis of the causes behind the development of asymmetric modes in a traction drive system that features direct torque control (DTC) of a rolling stock with asynchronous traction motors. The development of asymmetric modes in the traction drive system was found to be caused by the asymmetry of the supply voltage system, the asymmetry of the traction motor windings, and transient processes triggered by a change in the inverter supply voltage and variation in the traction motor load. At the same time, the asymmetric modes caused by the asymmetry of the feed voltage system and the windings of the traction motor are the emergency modes. The influence of the asymmetry of the feed voltage system and asymmetry of the windings of traction motor on the starting characteristics of the phase currents and flux linkages of the stator in the steady-state mode was investigated. In these cases, the ratio of the amplitudes of phase currents and flux linkages of the stator of different phases was found to be constant. The effect of a variation in the feed voltage and load acting on the motor shaft on the starting characteristics of phase currents and flux linkages of the stator was investigated in the case of absence of the emergency modes. In these cases, the ratio of the amplitudes of phase currents and flux linkages of the stator of different phases was found to not be constant. The amplitudes of the phase current and stator flux linkage were proposed as criteria for diagnosis and identification of asymmetric emergency modes. An algorithm and a structural scheme have been proposed for the diagnosis of emergency asymmetric modes in the traction drive system with direct torque control. Modifications to the traction drive system with direct torque control are suggested in order to diagnose the presence of faulty asymmetric modes and identify the damaged traction drive element.

The paper considers the influence of the level of production cost on the overall efficiency of the functioning of industrial enterprises in the conditions of the modern economy and its economic potential. The value of the cost of production as one of the key factors determining the efficiency of an industrial enterprise and the level of its economic potential is considered. The main components of the cost, methods of its accounting and optimization opportunities are analyzed. Practical recommendations for improving production efficiency through cost management are given. A comprehensive analysis of the structure and dynamics of production costs has been carried out, the main factors influencing the formation of the cost of production, in particular, resource intensity, energy consumption, organizational and technological level of production and managerial approaches have been identified. In this research, let’s focus on the importance of cost rationalization and increasing the level of accounting and control over costs as key tools for ensuring the competitiveness of the enterprise. To control the cost, such methods as break-even analysis, accounting by centers of responsibility, regulatory accounting, calculation by types of products are proposed for use. The effective use of these methods allows to identify inefficient costs, conduct a comparative analysis of costs by periods, and make informed management decisions. Among the main ways to reduce the cost of production, was identified: introduction of energy-saving technologies, automation of production processes, improvement of logistics, inventory management, revision of supply contracts, as well as motivation of employees to increase labor productivity. On the example of a generalized profile of an industrial enterprise, the influence of various components of costs on the profitability of products is analyzed. It has been found that timely changes in the market situation and avoid unprofitable decisions.

The object of this research is the process of formation of costs of enterprises for the production and sale of industrial products. The need for such a study is determined by the use of outdated methods of forming the cost of production at Ukrainian industrial enterprises, which are based on the actual costs of the enterprise. It is proved that the existing provisions of direct costing do not reproduce the provisions of the market pricing mechanism, since the market price is focused not on actual costs, but on the needs and preferences of consumers of products. A detailed study of the existing methods of forming the cost of production was carried out, among which special attention was paid to modern methods of target costing and kaizen costing, developed and widely tested by economists of Japanese enterprises. The main advantages of target costing and kaizen costing systems when they are used in the conditions of the Ukrainian economy are studied and substantiated. The systems proposed for use provide for putting in the first place not the actual costs, but the market price of the product, and the costs are formed taking into account the desired level of profit for the enterprise. This approach involves the integral (complex) use of target costing and kaizen costing. It has been proven that the combination of these two systems allows to create a continuous cycle of production cost management at all stages of the product life cycle. Target costing provides strategic cost control during the product design phase, while kaizen costing supports and increases efficiency during the production and operation phase. The combination of targeted costing and kaizen costing provides a significant increase in the efficiency of industrial enterprises, is an effective way to achieve strategic and operational goals, increase the competitiveness and sustainable development of industrial enterprises. This is achieved due to the complementarity of these systems at different stages of the product life cycle.