A detailed analysis of the end-to-end conductivity was carried out using experimental data from the measurement scheme, presented in the article. The oscillograms of changes in the time of the specific active conductivity of wheat grains of the given moisture at a given amplitude of vibration (on a direct current) were removed. Experiments have shown, that specific active conductivity varies from a value corresponding to a lack of vibration to a corresponding value, subject to vibration, i.e., almost more than 3 times. The minimum value of end-to-end conductivity when exposed to vibration, as shown by the experimental test, is almost an order of magnitude less than its average value. The decrease in the value of end-to-end conductivity relative to its average value is manifested in the intervals of time corresponding to the moments of movement of the sensor downwards, that is, in the direction of acceleration of gravity, under the influence of a vibrator. The work offers a way to measure the moisture of the grain mass and the device for its implementation. A distinctive feature of the developed method is that the controlled grain mass is filled in the cavity of the capacitive sensor and subjected to vertical vibration. The registration of dielectric permeability (moisture) is made at intervals of time corresponding to the minimum value of end-to-end conductivity. The proposed method makes it possible to significantly increase the accuracy of measuring the moisture content of the grain mass. This is especially important in conditions of high moisture.

Studies of the instrument error depending on the compaction of the grain sample in the sensor with free backfilling, forced sealing with a piston and under vibrating showed that the highest reproducibility of the readings, and therefore the lowest instrument error is provided, when exposed to vibration. Granular bulk materials change the volume only to a limited extent, even under the influence of external forces. The vibration action significantly reduces these forces, allowing the grains to be stacked more tightly. The stacking density depends on the vibration parameters. The use of vibration allows the stabilization of the volume density and simultaneous grain transportation through the sensor cavity. To use this method of preparing a grain sample, it is necessary to study its electrical specifications with this type of transportation. The vibration amplitude can be modified by changing the supply voltage of the electromagnetic vibrator. In this work, the dependences of the grain dielectric constant of different humidity in a high-frequency electric field on the vibration amplitude acting on it, are investigated. To determine the analytical expression that relates the grain electrical specifications with its moisture, volume density, temperature and frequency of the electric field, methods of active experiment planning are used in the work. Regression analysis of the experiment model showed its adequacy. Тhe results are required and can be applied, for example, in the development of in-line and discrete grain moisture sensors.

The ferro-vortex apparatus relates to devices of electro-mechanical processing of liquid, bulk and other blends used in agriculture, medicine, chemical, oil and gas industry, communal services and other areas. The energy of the rotating electromagnetic field is concentrated in the working area of the apparatus, which is conditionally limited by the external and internal diameters of the toroidal magnetic cores of electromagnetic elements (inductors) axial shape and the end surface of their tines. Wherein, the value of the working gap in the ferro-vortex apparatus is significantly larger than the air gaps in standard electric machines of both cylindrical and axial execution. The study of the electromagnetic parameters of the apparatus, created on the basis of recommendations received in the process of creating already existing prototypes, revealed a number of shortcomings. At the moment, there is no methodology that allows to design devices with optimal dimensions of magnetic cores of electromagnetic elements. When optimizing their design, it becomes necessary to manufacture new prototypes, which is associated with large time and material costs. An alternative to this is the use of computer technology and appropriate software for mathematical modeling. The article shows a mathematical model representing the dependence of the average diameter of the active surface of magnetic cores and the active length on the electromagnetic loads. When analyzing the model, the optimal ranges for adjusting the size of the working area (25-35 mm) and the magnitude of the magnetic induction in the air gap were determined (0.11-0.16 Т). On the basis of this model, a technique for designing devices with optimal dimensions of magnetic cores of electromagnetic elements is created.

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The methods of the electroaerosol technology are based on the use of electrostatic field forces and the properties of electric discharge in gases in technological processes. In agriculture, the use of electroaerosols has been used to protect plants. High voltage devices are used to create an electric field. When designing these devices, problems arise with high voltage sources. This is due primarily to the insulating properties of the circuit elements. It is necessary to carry out breakdown voltage calculations on the case and external elements of the device. For plant spraying systems, push-pull half-bridge high-voltage sources are most optimal. The main task in optimizing a high voltage source is to select a circuit, to determine the modes and characteristics of voltage. Designing a power source includes: determining operating modes and selecting power transistors; calculation and selection of elements of the voltage multiplier; determination of design parameters of a power transformer. The multiplier consists of elementary links. When combining several elementary links, at each subsequent node in the diode circuit, the constant component of the potential increases by the amplitude of the source. The proposed principles make it possible to obtain an algorithm for constructing a multiplier of any degree of complexity. Structurally, the most technologically advanced option is the use of components for surface mounting. To determine the parameters of the multiplier, numerical analysis (modeling) of a specific device and optimization of the circuit parameters to obtain the required characteristics are used. Among the advantages of the method can be called simplicity, quick results, sufficiently high accuracy, the ability to take into account the features of the elements used when using complex models for them. Experimentally output characteristics of the power source and voltage multiplier at real load are obtained.