electromotive force
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Purpose This paper aims to work out a method for calculating losses in induction motor steel taking into account its saturation. Design/methodology/approach The theory of electric machines is applied during the analysis of induction motor equivalent circuits. The theory of Fourier series is used to determine the harmonic components of voltage, current and power. Instantaneous power theory and trigonometric transformations are used to solve algebraic and differential equations and their systems. The methods of approximation and interpolation are applied to obtain analytical expressions from the experimental data. Experimental research was carried out to verify the reliability of theoretical provisions and research results. Findings A method for assessing an induction machine steel as a function of the generalized electromotive force has been proposed. It allows taking into account higher harmonics of the current, which are caused by the presence of nonlinearity of an induction motor magnetic circuit. Practical implications The obtained results can be used in calculating the energy characteristics and operating modes of an induction motor, as well as in the construction of control systems. Originality/value A method for determining the losses in the stator steel of an induction motor, using a generalized electromotive force, has been proposed for the first time. It enables taking into account the currents flowing both in the stator circuit and in the rotor circuit.

Abstract In this research, we investigate the thermoelectric effects of general materials. The results of this showed that an electromotive force was generated under a temperature difference between two points in materials. As no material has infinite electric resistance, an electromotive force is expected to be generated under a temperature difference in all materials. In conclusion, the thermoelectric effect generates an electromotive force. This electromotive force causes an electric current to flow, thereby generating a magnetic field.This magnetic field generates the Earth's magnetic field, triboelectricity, sunspots, and kinetic energy of celestial bodies.This temperature differential electromotive force also generates lightning and creates an ionosphere that reflects radio waves.

Abstract In this research, we investigate the thermoelectric effects of general materials. The results of this showed that an electromotive force was generated under a temperature difference between two points in materials. As no material has infinite electric resistance, an electromotive force is expected to be generated under a temperature difference in all materials. In conclusion, the thermoelectric effect generates an electromotive force. This electromotive force causes an electric current to flow, thereby generating a magnetic field. This magnetic field generates the Earth's magnetic field, triboelectricity, sunspots, and kinetic energy of celestial bodies. This temperature differential electromotive force also generates lightning and creates an ionosphere that reflects radio waves.

Thermodynamic properties of the Sb2Te3 compound were studied by measuring electromotive force (EMF) with a liquid electrolyte in the temperature range of 300-450 K. The partial molar functions of antimony in alloys and the corresponding standard integral thermodynamic functions of the Sb2Te3 compound were calculated for the first time based on the EMF measurements under standard conditions. Comparative analysis of obtained results with literature data was carried out

The ocean is a very important arena in modern warfare where all marine powers deploy their military forces. Due to the complex environment of the ocean, underwater equipment has become a very threatening means of surprise attack in modern warfare. Therefore, the timely and effective detection of underwater moving targets is the key to obtaining warfare advantages and has important strategic significance for national security. In this paper, magnetic flux induction technology was studied with regard to the difficulty of detecting underwater concealed moving targets. Firstly, the characteristics of a magnetic target were analyzed and an equivalent magnetic dipole model was established. Secondly, the structure of the rectangular induction coil was designed according to the model, and the relationship between the target’s magnetism and the detection signal was deduced. The variation curves of the magnetic flux and the electromotive force induced in the coil were calculated by using the numerical simulation method, and the effects of the different motion parameters of the magnetic dipole and the size parameters of the coil on the induced electromotive force were analyzed. Finally, combined with the wavelet threshold filter, a series of field tests were carried out using ships of different materials in shallow water in order to verify the moving target detection method based on magnetic flux induction technology. The results showed that this method has an obvious response to moving targets and can effectively capture target signals, which verifies the feasibility of the magnetic flux induction detection technology.

The non-inertiality of the rotating system of Faraday's unipolar generator forces us to address this problem using the principles of the general theory of relativity. The purpose of this study is to compare the theoretical quantitative estimates of induced electromotive force with the experimental results obtained from the corresponding measurements. The theoretical elaboration of this issue proves that the differences between the results of the general theory in relation to those of the special theory of relativity are some negligible terms, which are due to the non-inertiality of the rotating reference system. This result enables us to consider the theoretical estimates based on special and general relativity as equivalent, with quite satisfactory accuracy. Therefore, a very serious issue of inconsistency between the theory of relativity and the measurements of induced electromotive force emerges, since as already shown in the existing literature, this inconsistency, from the point of view of the special theory of relativity, is already proven.

The non-inertiality of the rotating system of Faraday's unipolar generator forces us to address this problem using the principles of the general theory of relativity. The purpose of this study is to compare the theoretical quantitative estimates of induced electromotive force with the experimental results obtained from the corresponding measurements. The theoretical elaboration of this issue proves that the differences between the results of the general theory in relation to those of the special theory of relativity are some negligible terms, which are due to the non-inertiality of the rotating reference system. This result enables us to consider the theoretical estimates based on special and general relativity as equivalent, with quite satisfactory accuracy. Therefore, a very serious issue of inconsistency between the theory of relativity and the measurements of induced electromotive force emerges, since as already shown in the existing literature, this inconsistency, from the point of view of the special theory of relativity, is already proven.

Various technologies have ever been developed to minimize the detent force of linear motors. Although the traditional modular structure can effectively reduce the detent force, the width of the flux barrier and the number of units severely limit its application. To solve these, this paper proposes a new modular type of tubular permanent magnet synchronous linear motor (TPMSLM), which consists of two identical unit motors. For simplification, a subdomain analytical method of the unit motor is firstly established, and its accuracy is verified by a comparison with that of the finite element method. Using the two approaches, the important parameters of the motor are analyzed. A modified two-unit modular TPMSLM is also proposed through the star vectograms of the electromotive force, which achieves thrust performance similar to the traditional three-unit modular TPMSLM with a smaller axial size. Moreover, to make full use of the volume of the flux barrier, end teeth are added at both ends of the unit motors. The simulation results indicate that a reasonable end tooth structure can not only reduce the magnetic leakage phenomenon of the end but also effectively improve the thrust of the motor.

In this paper, the operating principles of the acid battery and its features are discussed. The results of voltage tests containing the measurements conducted at the terminals of a loaded battery under constant load conditions, and dependent on time, are presented. The article depicts the principles of the development of electric models of acid batteries and their various descriptions. The principles for processing the results for the purpose of the determination and description of the battery model are characterized. The characteristics under stationary and non-stationary conditions are specified using glued functions and linear combinations of exponential functions, and the electrical parameters of the battery are determined as the components of the circuit, i.e., its electromotive force, resistance, and capacity. The dynamic characteristic of the battery in the form of transmittance was determined, using the Laplace transform. Possible uses of the crankshaft driving signals as diagnostic signals of the battery, electric starter, and internal combustion engine are also indicated.