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The suggested new wireless rotor induction machine consists of two sets of stator windings: primary and secondary. Each winding consists of one, two, or three phases. The laminated steel rotor, in wireless rotor machine, serves as a switcher of the magnetic field through output windings. By changing the configuration of the rotor poles, it is possible to create the sinusoidal waveform in the output windings. The rotor of the wireless rotor machine is rugged and cold. The cold rotor facilitates the cooling of the AC machine. In the wireless rotor induction machine, it needs double frequency of the voltage source for the same rotor speed as in the regular induction machines. That means that the suggested machine weightless than the regular induction machine with the same rating speed. In this case, the wireless rotor induction machine can find application, for example, as powertrain for the vehicles. The theory of wireless rotor induction machines now is not developed. In the paper, we consider the simulation of the wireless rotor induction machine to show that the principle operation of the wireless rotor induction machine is identical to a regular induction machine with a wound rotor. We use a phasor and vector representation of electrical and magnetic values. For simulation, we utilize graphical language, Simulink. The graphical language Simulink is visible, simple, and flexible. It allows designing the model according to the physical nature of the machine. We consider the induction machine as a close control system with feedback proportional to the motor torque. This new approach allows separate analyses of open and closed-loop control systems. After adjustment of all elements in the open control system, we insert feedback proportional to the motor torque. The results of this work can find the application for engineering education and professional design prototypes of the wireless rotor induction machines.

In the paper; we consider qualitative mathematical modeling of the DC machine with wireless rotor to determine steady state and dynamic properties of the machine. We take more attention to the physical interpretation of operation wireless rotor DC machine to show that the wireless rotor machine identical to regular brushes DC machine. For description static and dynamical properties of DC machine, we use graphical language simulation Simulink. In the Simulink model, we use new approach considering DC machine as a natural control system. Such an approach allows study DC machine as an open and close loop control system. It facilitates design and investigation model of DC machine. For simulation AC components of DC machine, we use its space vector representation. Space vector representation of sinusoidal components allows easy communicate AC and one-dimensional components DC machine in the model. The space vector representation and pulse width modulation of input DC voltages enables take into account nonlinear properties of electrical machine and improve their dynamical properties. We consider three cases of the model DC machine. One case, for ideal DC machine, when input DC voltages transform to a sinusoidal waveforms. Second case, when the input voltages transform to a rectangular waveforms. In the third case, we consider one phase model DC machine. In the first case, the results of the simulations show reduction of the time transient response and improve quality of control, in comparison with another two cases. Results of this work can find application in design of electric drives, based on DC machines with wireless rotor.

Under hardware, we consider magnetic circuits, windings, and power electronic circuits of a machine. Under software, we consider algorithms and electrical circuits with low level current for design: direct current, induction, or synchronous machine with wireless rotor. The basic hardware element is one phase machine with magnetic circuit, wireless rotor, and two coils on the stator. One coil used for excitation and another for output application. In the paper, we consider theoretical basics operation of one, or two, or three phase wireless DC and AC machines, when they designed by using the same hardware. The prototype of the two-phase electrical machine based on the two one phase machine placed on the same stator or on the common shaft where designed. Results of verification proves the theoretical results. Advantage of this design is in the simplification of fabrication electrical machines with wireless rotor. In high voltage machines, design machines with common shaft, facilitate isolation problems between different phases.

In this paper, we consider a new design of a synchronous motor with salient rotor poles and all coils placed on the stator. This design uses a laminated silicon steel rotor, which is not as expensive as a rotor with super strong permanent magnets. This machine design eliminates copper rings on the rotor and brushes which is used in regular synchronous motors, and eliminates disadvantages involved with these arrangements. In theoretical basics of analyses and design of synchronous motors we pay more attention to the single-phase motor because it is the basis for design poly phase synchronous machines. In the paper, we suggest a new single phase, and two phase synchronous motor configuration. These synchronous machine configurations can work in DC mode operation without changing the electronic power circuit. This property can also be used for starting synchronous machines. The prototype, a two-phase synchronous motor was designed and tested. The single-phase motor was tested on the base two phase motor. Results of the test of the prototype machine confirm the main useful properties of synchronous machines.

The paper represents results of an investigation of distribution of the magnetic field intensity near the equipment of the 500 kV power substations in Russian Federation. The investigation is conducted with position of security life activity of the technical personnel.

Data on the spectral composition and intensity of electromagnetic radiation of corona discharge are obtained in an experimental study performed on the outdoor switchgear of the Shagol 500-kV substation of the Chelyabinsk Enterprise of Trunk Transmission Grids and under a 500-kV Shagol – Kozyrevo overhead transmission line. The electromagnetic environment on the territory of the 500-kV outdoor switchgear is shown to be determined by narrow-band radiations (harmonics of the frequency of electric supply) and wide-band radiations due to corona discharges of high-voltage sources. This means that the personnel experience the action of a commercial-frequency electric field and electromagnetic radiation of a quite wide range, which is not allowed for by the existing guidelines. It is recommended to continue the study in cooperation with medical institutions in order to create guidelines that would allow for the joint action of commercial-frequency electric field and electromagnetic radiation and for the voltage in the line, the current load, the meteorological situation, and other factors.

The paper presents results of an investigation of distribution of the electric field intensity near the equipment of the 500 kV power substations in Russian Federation. The investigation is conducted with position of security life activity of the technical personnel.

The high level electric field intensity produced by high voltage inside 500 kV power distribution substations is harmful for the human (staff) health. It is very important to have knowledge about levels distribution of electric field intensity within power distribution substation. The paper presents results of investigation 50Hz electric field intensity distribution inside 500 kV power transmission substations in Russian Federation. The measurements of electric field intensity were done inside of twenty six power distribution substations. On base of the measurements, the map of the electric field intensity distribution was build for each substation. These maps are used for planning service works or for inspection of equipment on power substations. In the paper, there are estimations, in percents, what value of substation territory is occupied by different levels of electric field intensities.

Super high voltage power transmission lines can be a source of harmful electric and magnetic fields for environment. This paper discusses results of the experimental measurements of these types of fields under real world transmission lines 110, 220, and 500kV. The measurements are fulfilled by using an electric and magnetic fields meter and analyzer. The level of fields parameters at frequency fifty hertz is highest and can exceed permitted maximum for people. The most visible components in field spectra are third and fifth harmonic. The level of magnetic field components does not exceed permitted maximum values for professional and civil people. The change of the ground relief under transmission lines can significantly change level of electric field. This level can exceed the permitted level for people.

The brushless DC motors with permanent magnets are used primarily in law power applications. There are no limits on weight and motor dimensions in considered motors with DC stator excitation. Brushless series connected machine with DC stator excitation do not have rotor coils. Field coil and armature coils are mounted in the stator. Armature windings are connected to DC voltage source trough power transistors commutator. Power transistors are controlled by reflective optical sensors in function of rotor position. In the report, the new principle design of the motor with DC stator excitation is considered. The new principle of design supposes individual excitation for each of the armature phase. Such approach gives an opportunity to design electrical machine with any number of armature phases spaced in phase from each other. In series connected DC machines, the field winding is connected in series with the armature winding. In general, the series connection leads to a torque-speed characteristic that is useful in transport and crane mechanisms where need high start torque. For realization series connected machine with DC stator excitation, the number of armature phase can be two, three, or more. Increasing number of phase leads to more complicated design of machine and gives some advantages in performance. The minimum two or three phase gives the simplest design power electronic controller and the sensors position circuit. Like DC universal motor, the machine with series connected DC stator excitation, in principle, can operate from either from AC or DC voltage sources. The universal mode operation is described in this paper when motor operate from one phase AC voltage source. The prototype of two phase motor with DC stator excitation was realized on the base of a car alternator. Results of tests prototype motor and modeling in steady state condition prove that the property of brushless machine with DC stator excitation similar to those series, shunt connected, and separate exited DC machines. Considered machine can find application in the electric drive cars and hybrid electrical vehicles. Copyright © 2012 SAE International.

Alterative current transmission lines with voltage of 500 kV are the most powerful source of electro-magnetic non-ionizing radiation. The investigation of radiation effect on technical personnel began in Russia as early as 1953 after the construction of the first 220 kV transmission lines, when the first signals of health worsening of workers appeared. The research results which are presented in this report was carried out by the authors during the period from 1997 to 2007 on different enterprises of main network systems of the Ural and Western Siberia Russia. The experimental investigations were carried out near functioning line of 500 kV, in a zone of the greatest electric field intensity. The method of passive experiment was used during the research. It assumes the measuring by in advance planned combinations of factors which may influence on the considered parameters. At the first stage it was the parameter the electric field intensity (50 Hz frequency). The factors which theoretically can influence on the value of electric field intensity are the following: Voltage of transmission lines of 500 kV; Load current with position of its influence on heating of the transmission line in compare to air temperature and change of line sag over the ground; Atmospheric effects (including air temperature, absolute and relative air humidity, wind speed, speed pressure of wind). The correlation analysis was made by using of received experimental results. According to the results of the correlation analysis, it was made a conclusion that the greatest influence on the amount of electric field intensity under transmission line is made by the factors that can change the line sag and consequently the distance from current-carrying parts to points of measurement. Besides, the distance from current-carrying parts to ground surface is influenced by the change of relief where transmission lines run. Local rising and lowering of the ground level under this part of transmission line may lead to considerable change the electric field intensity, bias area of maximum intensity from line centre, and distort the symmetric picture © 2011 IEEE. IEEE Region 4 (R4)

In the report, a new version of machine with DC stator excitation is discussed. A brushless one phase electrical machine has a very simple design. Rotor has no windings. In generator mode operation, stator has one winding for DC stator excitation and one output winding. In motor mode operation, there is only one sensor of rotor position and one phase H-bridge inverter. One phase machine is symmetrical. Like in dc machines, it is possible to realize here: shunt, series, and separate excitation. In motor mode, the speed control is possible by vary armature (output winding) voltage, varying current excitation, and varying resistance in armature circuit. Simplicity construction and flexibility control opportunities can find for this machine wide application in vehicles. Motor, with series excitation, leads a torque-speed characteristic that is useful for transport power circuit applications. One phase machine is the basic for design of two and three phase machines. The basic principle operation of one phase machine with dc stator excitation is discussed in the report. The power electronic circuit and sensor position circuits are described also. The prototype one phase machine is implemented. The experimental results confirm speed motor control opportunities and simplicity design of the one phase machine with dc stator excitation. © 2010 SAE International.

Power field effect transistors are used and will be used in almost all automotive systems. Control of field effect power transistors requires isolated 5V control signals and isolated 12V DC sources. The first problem is resolved by using optical pairs: light emitting diodes with phototransistors. The second problem can be resolved by using impulse voltage sources. The primary coil of a transformer is connected to the battery by a transistor switch. In the first period of operation of this voltage source, the energy is stored in the magnetic field of transformer's inductance. In the second period, the energy is delivered to the output voltage source. Energy is delivered from the secondary transformer's coil to the output capacitor through a diode. As a rule, one separate voltage source has a small power, that is why one impulse voltage source can have the necessary number of isolated output voltage sources, i.e., 3, 6, 9, 12, etc So, we can design an impulse DC to DC voltage source with multiple isolated output voltage sources. By changing the charge time of the inductor, we can control the output voltage by using negative feedback proportional to the output voltage and/or current. In the report, different variants of impulse voltage sources are considered, with analog base elements and on the base of microprocessors. Analyses operation of these impulse voltage sources gives us an opportunity to determine the period (frequency) of internal operation with ordered maximum transformer efficiency values. The concept of controlled impulse voltage sources is very important because these sources are very simple. They are reliable and have high level of electrical isolation. Copyright © 2009 SAE International.

For protection electric substations personnel from harmful effects of the super high voltage electric field, it is need to measure the level and time of electric field exposition of personal by using mobile electric field measurement instrument. The instrument are placed in mans helmet close to a head in area of high electric field intensity. Standards for limited vales of electric field intensity are estimated for undistorted electric field. As a conductor, the human body distorts the original electric field around the body and device shows distorted value of electric field. Investigation of level distortion by the finite element method and the experimental measurements shows that the maximum distortion appears with change of height of the person and at change parameters of foot ware soil. These parameters, height of the person and foot ware soil data should be used for design of a measurement devise and for adjustment the device before measurements. Change of other person parameters can be ignored because of very law level of changes field distortion.