A sensorless initial rotor position's estimation for permanent magnet synchronous machines

Permanent magnet synchronous motors for the effective start require information about the initial position of a rotor. In this regard, most systems use position sensors, which substantially increase entirely a cost of an electrical drive [1-3]. The aim of this article is to develop a new method, allowing determining the absolute angular position of the permanent magnet synchronous motors' rotor [4,5]. With a certain voltage pulses applied to the motor, its stator is magnetized by currents leakage in the windings. This allows using a special algorithm to calculate the absolute position of the rotor without using any motor parameters [6]. Simulation results prove the simplicity and efficiency of this method for determining an initial position of the permanent magnet synchronous motors' rotor. Thus, this method can be widely used in the electrical industry

The electric drive control system of corner reflectors of the spacecraft interferometer

This paper presents the electric drive control system of corner reflectors of the infrared Fourier transform spectrometer for meteorological satellite. Limited-swing brushless DC motor with a torsional bearing is used as a drive motor. Stringent requirements are imposed to the drive control system for stabilization of moving speed of the reflectors while obtaining the interferogram and for limitation of the reverse time. Research of influence of torsion on steady-state error of speed and ways of its compensation is conducted. The obtained results are consistent with the simulation results of the drive. It is shown that the developed drive is operable in a spacecraft system

The electric drive control system of corner reflectors of the spacecraft interferometer

This paper presents the electric drive control system of corner reflectors of the infrared Fourier transform spectrometer for meteorological satellite. Limited-swing brushless DC motor with a torsional bearing is used as a drive motor. Stringent requirements are imposed to the drive control system for stabilization of moving speed of the reflectors while obtaining the interferogram and for limitation of the reverse time. Research of influence of torsion on steady-state error of speed and ways of its compensation is conducted. The obtained results are consistent with the simulation results of the drive. It is shown that the developed drive is operable in a spacecraft system

The control system of synchronous movement of the gantry crane supports

The paper presents study findings on synchronization of the gantry crane support movement. Asynchrony moving speed bearings may lead to an emergency mode at the natural rate of deformed metal structure alignment. The use of separate control of asynchronous motors with the vector control method allows synchronizing the movement speed of crane supports and achieving a balance between the motors. Simulation results of various control systems are described. Recommendations regarding the system further application are given

Development Of The International Social Entrepreneurship Institute Through Propaganda And Education Mechanisms

The article studies factors influencing the development of social entrepreneurship in the Russia in comparison with other countries. The development of social entrepreneurship in the modern world plays a significant role for the state and society. The conducted research shows the scale of social entrepreneurship and the impact of many different factors on its effective development. The article found out that social entrepreneurship in Russia can develop along a synthetic path that includes features of both countries as with a liberal economy as more socialist-oriented. In Eastern Europe, thanks to the USSR legacy, the tendency to provide population with social services through state, financed and managed mechanisms has remained. As studies of the social services sector in countries with liberal economy showed, for example, the USA, social entrepreneurship is encouraged by the state with the help of fiscal preferences. At the same time, the state practically does not provide social services transferring them to private capital. In countries with a more socialist-oriented economy, the state financial and regulatory role is more pronounced, social services are regulated in detail and are rendered both by state institutions, and within the framework of public-private partnership and private capital. In addition to factors, the author identifies the actual problems and trends in the development of social entrepreneurship through propaganda and education means. Proposals have been made on the synthetic development of the social entrepreneurship institution through education and promotion mechanisms applicable in countries with similar socio-economic conditions

Injection Process Control of the Well at the Hydrodynamic Research of Coalbed

This scientific work is devoted to the study results of water injection process into the well at the hydrodynamic research by using the high pressure unregulated pump. The injection process should be accompanied by the retention of some hydraulic parameters at constant level during some time. Various variants for use of mechatronic nodes for automatization of water injection process are considered. Scheme for reducing the load on the pump and equipment in hydraulic system and also for improving the quality control system with high accuracy is shown. Simulation results of injection process into the well at the pressure and consumption fixation and recommendations for the use of the proposed schemes depending on the technological process are given