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The technique of experimental research of static, dynamic and thermal characteristics of elements of automation systems based on the use of traditional equipment and special algorithms of information processing is developed. The reliability of information determination is increased by the use of the method of synchronous signal detection in determining the frequency characteristics of the studied elements of automation. An experimental study of the input and output signals of the amplifier module for two modes of operation was carried out, which confirmed the prospects for using an adaptive power supply for the output stages of the amplifier module when working with non-stationary loads. The method of setting up two modes of operation of the elements of the control system for agricultural facilities with non-stationary power sources, including the choice of parameters for the elements of the system, the experimental determination of its parameters and the choice of parameters for corrective relationships, has been proposed.

The diesel electric tractor DET-250M2 was the first tractor in the USSR with an all-electric transmission. This tractor usually works in agriculture as a cultivator and a bulldozer. However, it is often used in the railway sector, in industry, in large construction projects. Since the tractor’s electrical installation developed in the 1950s on the basis of DC collector machines is now obsolete, difficult to maintain, it was decided to upgrade the traction electric drive. The article presents the calculations of an electric machine: optimization of the rotor geometry, selection of the optimal ratio of the pole and interpolar gap, selection of the optimal number of poles of the machine, selection of the current shape, type of rotor. As an electric machine, a FRRM, which characterized by high overload capacity, a wide range of work in terms of torque and speed, was selected.

The article analyzed and identified the main sources of interference, disrupting the work and reliability indicators of the system, which can lead to malfunction of system of microprocessor relay protection and automation for electric stations and substations, as well as elements and actuators of open distribution devices. According to official data, modern microprocessor-based relay automation systems operate with a reliability coefficient that is not lower than 0.998. Further increase in reliability requires the development of technical measures, namely, requires the use of power and signal cables that must meet the requirements for specific parameters of inductance, capacitance and active resistance, and also requires the use of special placement of cross sections of conductors inside the cable. Secondly, it is shown that to increase the reliability of information transmission it is necessary to switch to serial communication channels, but the amount of information per channel should be strictly limited. The estimation of economic indicators of the system and its dependence on the reliability of the system is given. Thus, with an increase in reliability by 1.5-2 times, it is necessary to increase the cost of design and commissioning of such a system by about 2 times. It is recommended to use in addition to the regulated maintenance procedures a mandatory assessment of the level of interference in the system in order to maintain a stable and reliable operation of the relay automation system. Experimental and calculated data confirmed that the most difficult situation to ensure the reliability of the system is associated with thunderstorms and lightning. This circumstance dictates the necessity of evaluation and measuring the parameters of a common system of earthing. The methods of evaluation and diagnosis of faulty components of the system are proposed.