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The sources of non-self connection to the grid and non-linear loads produces high harmonic currents. This paper presents a study of a harmonic compensation system and reactive disturbances using a photovoltaic generator. The system consists of a voltage inverter which acts as an active filter and a photovoltaic generator parallel as a source of electrical energy. The main simulation and principal...
In recent years, Fuel Cells (FC) have gained interest as energy source for stand-alone and grid connected applications, because they are very high-efficiency and multi-fuel power generators that require neither the burning of conventional fuels nor the mechanical equipment of conventional power generators. When FC are used with inverters for supplying AC loads, harmonic distortion in the supply voltage...
Fuel Cell systems require power conditioning to interface them to loads or the utility grid. In single phase applications normal operation of the power conditioning converter introduces a significant second harmonic current ripple that reduces the power availability of the stack up to 20%. A similar effect can be observed in three phase applications operating under unbalanced loads. To mitigate this...
With the development of the current power generation technology, power quality of the generation system becomes a new problem, because of ocean energy variable and converters with large power electronic device applied. A real-time signal detection and harmonic analysis is great significance to improve power quality. The paper mainly proposes how to use LABVIEW software platform to develop a power...
This paper deals with an aircraft weight optimization through an analysis of different load-converter-architectures. A major effort in the development of new aircraft is the reduction of the weight. This results from a direct relationship between aircraft mass and efficiency. At a first step the global onboard converter architecture is analyzed. In addition to the conventional architectures two DC-grid...
Basic principles of a new type of induction motor, called Variable Impedance (Z) Induction Motor (VZIM), are introduced. The main goal of implementing this new structure of induction motors is to counteract the existing compromise in the design stage of induction motors between high starting torque at standstill and high breakdown torque and high efficiency at rated speed by combining these features,...
This paper describes a finite element (FE) based phase-variable model for double-star permanent magnet synchronous machines. In a double-star configuration where two three-phase windings are spatially shifted by 30 electrical degrees, a high amount of the 5th and 7th current harmonics may be excited because of the winding layout. However, a conventional d-q axis model considers only fundamental components,...
The Shaded Pole Single Phase Asynchronous Motor represents one of the most common and popular electric machines used for general purpose. It is a peculiar application in electric machinery because even if it is characterized by large scale production volumes and easiness in construction, the Shaded Pole Asynchronous Motor is also known as a complex technological appliance from the point of view of...
This paper investigates a dual three-phase permanent magnet synchronous machine supplied by two independent three-phase voltage source inverters (VSIs). Dual three-phase machines have many important advantages compared with their conventional three-phase counterparts. Instead of six-phase converters and special vector controls, it would be a very interesting alternative to supply these machines by...
This paper presents a topology of an on-board charger with direct grid connection for battery electrical vehicle in which the system components are adapted and optimized by integrating the electrical machine and the voltage source inverter of the traction drive into the charging strategy. The particular safety issues concerning the impact of the common mode voltage in the charging operation are pointed...
The paper deals with some aspects of soft starter application. Influence of heating and voltage drop restrictions on starting process are discussed. It is shown that there is an area of the correct application of soft starter.
This paper presents the control of a multilevel inverter supplied by a Photovoltaic (PV) panel and a batteries bank. It is well known that the power quality of multilevel inverter signals depends on their number of levels. However, the question that arises is whether there is a limit beyond which it is not necessary to increase the number of level. This question is addressed in this paper. Three,...
In this study, a single stage, three-phase, three-level neutral point clamped inverter is designed for grid connected renewable energy systems. The proposed voltage source inverter is operated in current controlled mode and a PI current controller is used for the production of switching pattern. Also the proposed inverter is operated in parallel with public grid by using phase locked loop method....
The time and the space waveform of electric and magnetic magnitudes of AC machines are a non-sinusoidal including the case of powered by the grid. The reasons of the deformation are in the actual design layout of electrical machines, at various asymmetry generated in the production or as a result of failures in electric, magnetic and mechanical parts of the machine. The rotating electric machine may...
Multi-phase electrical motors offer high reliability thanks to their capability to operate safely even in case of faults such the loss of one or more phases. This paper presents a new vectorial approach that allows to obtain the optimal current references for a multi-phase permanent magnet synchronous motor under open-phase fault condition. The approach is as general as possible: the proposed control...
This paper studies the effects of static eccentricity on back-EMF of Axial Flux Permanent Magnet Machines (AFPMM). Effect of static eccentricity on back-EMF of AFPMs has not been studied before. Many studies have demonstrated that accurately assessing the behavior of Axial Flux PM Machines is not an easy task. Use of numerical modeling makes it possible to precisely study the eccentricity in these...
The article deals with the special mathematical method with the help of which it is possible to calculate the RMS value of arbitrary voltage or current PWM impulses occurring in power electronics. Impulses may have continuously variable duty cycle as well as continuously variable top and bottom covers. The tool is suitable predominantly for the analysis of voltage and current impulses occurring in...
In the last couple of decades harmonics have become a major power quality problem in electric power system through the world. Harmonics are a distortion of the normal electrical current waveform, generally transmitted by nonlinear loads. It is important to identify the harmonic sources in the system and prevent related problems. In the paper are presented voltages and current distortions due to harmonics,...
The paper presents some issues on testing the generators, integrated in wind turbine systems. Generators are subject to perturbations transmitted from the source to the source and to perturbations determined by the variable speed of the turbines' blades. The paper reviews the standards concerning tests in wind systems and depicts some specific tests, using a programmable source and specific standard...
In this paper is presented an approach in development of measurement system (MS) for analyzing the power quality (PQ). The main aim of this paper is to present procedures of PQ measurements according to the strictest norms and standards and to develop a system for measuring specific indicators of PQ. The developed MS is implemented on several examples. In this paper is presented an example of implementing...
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