The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
This paper investigates the performance of a 150 W single-phase current-source grid-connected inverter for photovoltaic (PV) applications. The constant-current source is realized using a large DC link inductor and the inverter is implemented using a single boost switch, a H-bridge inverter and a CL output filter. Although the DC link inductor causes the inverter to be less efficient than an equivalent...
This study presents the analysis, design, and implementation of a photovoltaic (PV) inverter for residential applications based on interleaved flyback topology operated in discontinuous current mode (DCM). It is expected that the use of solar energy in small electric power system applications will increase largely when the cost of the PV panels and the energy conversion equipment becomes economical...
During the first steps of machines design, engineers have to choose the topology the most appropriate to the specifications. The topology includes the number of stator's slots, the number of rotor's poles and the winding associated. Traditionally, designers choose one of the common used topology in the industry and consequently, a lot of solutions are not studied. In fact, the performances of the...
This paper presents a Model Reference Adaptive System (MRAS) applied to the sensorless control of a DFIG system. The performance of the MRAS is enhanced by introducing a voltage model bandpass filter approximation to compensate for drift. Control is performed by a rotor-side matrix converter and is limited to the most common speed range in wind systems. Moreover a detailed analysis of the effects...
This paper presents a comparison of two-level and three-level converters for high frequency drives. The maximum output power per chip area is calculated and compared by the Total Harmonic Distortion (THD). A variable DC-link voltage is assumed and it is derived, that the three-level topologies suffer more from an increasing DC-link voltage than the two-level inverter. The influence of the cooling...
A lot of power electronic conversion devices are used in the variable frequency AC power system. Harmonic pollution and voltage distortion have serious impact on power quality, and voltage distortion spectrum is an important indicator to measure the electric power quality of aircraft. The distortion spectrum is analyzed for aircraft VFAC power system. The frequency ranged 360 ∼ 800Hz brings a wider...
This paper proposes a single-phase algorithm used to estimate the frequency, as well as the phaseangle of the utility grid. The algorithm uses self-tuning filters (STFs) operating in conjunction with low-pass filters (LPFs). The STFs are used to extract the fundamental components of the orthogonal voltages that represent a fictitious two-phase stationary reference frame (αβ-axes), while the LPFs are...
The main objective of this paper is to investigate the behaviour of Doubly-Fed Induction Generator (DFIG) under various grid disturbances. In order to study the dynamic response of DFIG, to emerge the faults' consequences, a model has been simulated in Matlab/Simulink. In addition, FFT analysis has been done to achieve fault diagnosis and identification. The disturbances that have been investigated...
This paper presents a method for frequency analysis of traction drives supplied from a dc trolley wire with an input LC filter. The proposed method is suitable for frequency analysis of the traction drive in whole speed range and enables to find resonant or other observed harmonics in the operating drive circuit which could cause dangerous oscillations particularly at resonant frequencies of the power...
This paper presents a novel approach to obtain an improved position signal from optical encoders. The approach is based on a two correction stages by identifying and correcting the systematic errors in a wide speed range of high-speed electrical motors. The experimental results underline the performance of the discussed methods.
This paper proposes the use of a three-phase four-leg (3P4L) converter in combination with an LCL filter for the inverter stage of a solid state transformer (SST). This configuration gives full control over the line-to-line, as well as the line-to-neutral voltage and currents, while providing exceptional harmonics mitigation. A procedure to calculate the passive components for the LCL filter is presented,...
Energy saving technology for electrical drives becomes high attention. Low harmonic drives reduce losses in the power supply. However, compare to the conventional drives, these have lower efficiency. In this paper the different kinds of adjustable speed low harmonic drives are compared. A new low harmonic drive with an integrated active filter is presented, which shows strengths of the harmonic mitigation...
The paper deals with problems of cylindrical rotor synchronous machine excitation winding, its design and analyses of resulting excitation magnetic field. Furthermore it includes possibilities of suppression of harmonic components using suitable stator winding topology.
This paper proposes a novel algorithm employed to detect both the phase-angle and the frequency of the single-phase utility grid voltage. The proposed algorithm uses an adaptive notch filter (ANF) operating in conjunction with a Phase-Locked Loop (PLL) system, yielding an algorithm called ANF-αβ-pPLL. The αβ-pPLL structure is based on the instantaneous active power theory for three-phase power systems...
This paper deals with a new concept and analysis of direct power control (DPC) switching table for a three phase shunt active power filter (SAPF) to improve power quality. The active power reference is obtained from the VSI dc-bus voltage controlled at the required level using an integrator proportional corrector. Compared to their references, active and reactive powers are directly controlled by...
Active power filters are often proposed as flexible solutions to tackle power quality problems in electric distribution systems. The need for tracking harmonic currents and voltages with these electronic devices exceeds the capabilities of conventional Proportional+Integral controllers and more sophisticated algorithms are sought. This paper presents a control method based on multiple reference frames...
Because of the ambitious plans of the German government to have 80 % renewable electric energy production by 2050, the German transmission system operators (TSOs) are facing difficult decisions when it comes to supplying sufficient amounts of reactive power to provide voltage stability and sufficient transmission capacities without building a large numbers of new transmission lines. One possible solution...
Losses analyses of laminated magnetic materials subject to non-sinusoidal magnetic flux are presented. Comparative analyses on typical Fe-Si oriented and non-oriented grains and nanocrystalline materials are carried out considering the influence of harmonic phase shift and associated B-H minor loops. Experimental measurements are performed to illustrate the B-H characteristics behaviours. A special...
A lumped parameter model describing the electromagnetic behavior of Transverse Flux Machines is proposed. Varying magnetic conductivities along the rotor perimeter representing the effective air gap are used to determine the harmonic effects on current dynamics and torque generation. To reduce torque ripples, a control scheme is presented.
This contribution investigates the influence of magnetic saturation on the sensorless control of IPM synchronous motors. An extended analytical motor model is introduced that covers magnetic anisotropies and describes the fundamental wave as well as the harmonic characteristics. Simulation results are compared to actual measurements on a servo drive.
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.