B. F. Simonov

Failure Features of One-Dimensional Model of Block Media under Sustained Uniaxial Loading

It is established experimentally that, in block geomedia, under conditions of sustained (months) uniaxial loading, the normal tension cracks can appear and develop under the action of stresses which are less than the ultimate strength in uniaxial compression of the corresponding geomaterial samples by an order. The features distinguished in the experiment on failure of one-dimensional block model of geomedium are compared with the results of visual and instrumental observations of failure character of the ore masses of the Talnakh-Oktyabrsky deposit.

Voltage stabilization in permanent-magnet synchronous generator with variable rotation frequency

The paper proposes the analysis of three design and control scenarios for the system intendeded to generate the variable-frequency and constant-voltage electric energy on the basis of a synchronous generator and a paralleled semiconductor converter. The research scientists demonstrate the stabilization of the synchronous generator voltage, evaluation of basic electrical parameters, and the relationship between them and operation modes of the system.

Mechatronic system “synchronous generator-three-phase bridge rectifier” for self-contained power facilities

The processes in the system composed of a continuous magnet synchronous generator and a three-phase bridge back emf rectifier are under analysis in this article. Such systems are usable in self-contained facilities to charge accumulation cells in mines and open pits. The authors determine possible regimes of the systems under varying rate speeds of synchronous generator shaft and altered commutation delay angles of the controlled rectifier, derive analytical expressions for determining parameters of the analyzed system, and find generated power limit.

Voltage stabilization system for power installations in mines

The authors analyze feasibility of voltage stabilization for permanent magnet synchronous generators in independent variable-frequency power networks. The method of voltage stabilization is based on series connection of the generator and a semiconductor converter generating wattless power. Basic energy characteristics of the semiconductor converter and synchronous generator are analytically defined, frequency constraints of the proposed method are found, and rational frequency range and overall power of the system are determined.

Calculation procedure for electromagnetic processes in multilevel semiconductor converters for electrical equipment in mining

The authors propose a calculation procedure for electromagnetic processes running in converters with clamp diodes based on the numerical simulation and method of switching functions. The procedure is specific for the capacity to calculate basic indices of energy efficiency of semiconductor converters in various work modes. Moreover, the procedure is universal in terms of number of voltage levels and number of phases. Owing to modern computation techniques, the time and labor inputs in the calculation is greatly reduced. The proposed procedure has been experimentally tested.

Residual oil pockets and their stimulation in productive formations

The article analyzes processes running in an oil pool under contour water flooding and resulting in formation of bypassed oil. Based on stability criteria, the authors discuss destabilization of the residual oil pockets by vibration so that the bypassed oil becomes proved & developed.

A new approach to voltage regulation in self-sustained power supply systems in mines

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.

Pulsed Linear Solenoid Actuator for Deep-Well Vibration Source

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.

Permanent-magnet synchronous generator voltage stabilization by rotation frequency variation in self-contained power supply systems

Under consideration is feasibility of voltage stabilization in permanent-magnet synchronous generator with variable frequency in self-contained systems of power supply. The method of stabilization is based on varying speed of rotation of generator shaft. The authors have derived analytical expression for regulating characteristics and determined required ranges for rotational frequency variation at preset parameters of generator and loading. The symmetry conditions are found for a regulating characteristic relative to rotational speed change.

Automated System for Physical Modeling of the Stress-Strain State of Block Structures in Geomedium

Development of construction principles and creation of automated systems for physical modeling of the block geomedium behavior in the varying unequally component stress field are considered currently as one of the strategic problems in nonlinear geomechanics. The scheme of stand for physical modeling and measuring-computational equipment oriented to the solution for fundamental problems of geomechanics are presented.