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Advancement of wave action stimulation and cross-well seismic imaging in mineral mining governs the need for downhole sources of elastic vibrations. The presented periodic electromagnetic seismic source is equipped with a mechanical–hydraulic drive for fixturing in a hole and for impulse transition to rock, and an electromagnetic impactor for pressure pulse generation. This article presents the experimental studies into the operation of the seismic source of three structural layouts. The features of the operation are discussed. The supply voltage dependences of the main parameters of the seismic source are obtained, and the practical application recommendations are formulated.

The article presents a case-study of mathematical modeling of electromagnetic and electromechanical processes in a downhole vibration exciter EM drive. The authors propose the mathematical model of EM drive on the basis of a double-acting EM machine. This model maintains a wide-range analysis of transient and quasi-stable operating regimes. The algorithm and implementation of the model using the structural modeling methods and means in the Matlab Simulink environment are described. The model verification is carried out by means of comparison of the simulation and physical models of EM drive within the configuration of downhole pulse vibration exciter. The appropriateness of the model is proved. The authors give recommendations on further improvement of the model and its accuracy in calculation of dynamic behavior of drives.

The experimental research of processes running in a linear pulse electromagnetic motor of a downhole vibration generator is described. Based on the research findings, design requirements and recommendations on basic geometrical proportions of the equipment are formulated.

The researchers analyze energy processes running in an autonomous electric power system consisting of a synchronous permanent magnet generator and a semiconductor converter. Current, voltage and capacity of key components of the system are evaluated, and the system operation modes are determined for the variable magnitude and character of applied load at the constant voltage output frequency. Parametrical law is proposed to control semiconductor frequency converter serially connected to load and generating reactive power. The influence of the converter on the basic design parameters, energy specifications of the synchronous generator and the system as a whole are evaluated.

Aimed at improving efficiency of non-explosive vibroseis method, the new concept of using a solenoid impact actuator enables essential increase in useful mechanical work with the limited external diameter. The results of the finite element modeling of magnetic field are reported. The authors have found the force and energy characteristics of the actuator and the prospects for its application in a casing with the external diameter limited to 120 mm.