Three-phase

About: Three-phase is a research topic. Over the lifetime, 16801 publications have been published within this topic receiving 159477 citations.

On comparing the symmetrical and non-symmetrical selective harmonic elimination pulse-width modulation technique for two-level three-phase voltage source converters

Abstract: Selective harmonic elimination pulse-width modulation (SHE-PWM) techniques offer a tight control of the harmonic spectrum of a given voltage waveform generated by a power electronic converter along with a low number of switching transitions These optimal switching transitions can be calculated through Fourier theory, and for a number of years quarter-wave and half-wave symmetries have been assumed when formulating the problem It is shown recently that symmetry requirements can be relaxed as a constraint This changes the way the problem is formulated and different solutions can be found This study presents different formulations of the problem, namely quarter-, half-wave symmetry and non-symmetrical waveform A critical evaluation and comparison between the three schemes are reported here based on various aspects, such as number of eliminated harmonics, harmonic spectrum profile, harmonic phasing, converter performance, computational time and solution space limitations Selected simulation and experimentally validated results are presented to confirm the theoretical work of this study This manuscript is a revised and extended version of earlier paper that was presented at the IEEE PESC 2008, Rhodes, Greece, 15-19 June 2008, and has not been submitted to any other journal for consideration and possible publication

A bidirectional series resonant matrix converter topology for electric vehicle DC fast charging

Abstract: A series resonant matrix converter (MC) based topology for high power electric vehicle (EV) battery charging is presented. The system performs DC fast charging and is capable of bidirectional power flow, for V2G (vehicle-to-grid) applications. The proposed topology can be divided into three sections: (i) a front-end 3×1 matrix converter, (ii) L r C r series resonant tank and high frequency (HF) transformer, and (iii) a single phase PWM rectifier. The matrix converter takes a three phase line frequency voltage and produces a high frequency (14.94 kHz) AC output. The resonant tank frequency is set to 13.7 kHz and helps to achieve zero voltage switching (ZVS) turn ON and low turn OFF switching losses. The secondary of the transformer is then interfaced to the EV battery bank through a PWM rectifier. The advantages of such a system include high efficiency due to soft switching operation, low VA transformer ratings due to resonant operation, and high power density due to the absence of electrolytic capacitors. A design example rated 30 kW, which charges a 500 V battery system, is presented. Analysis and simulation results demonstrate the performance of the proposed bidirectional topology. Preliminary experimental results are provided for a scaled down prototype operating at 500 W using a 15 kHz ferrite transformer.

Implementation of adaptive fuzzy logic and PI controllers to regulate the DC bus voltage of shunt active power filter

Abstract: The output gain of the adaptive fuzzy controller (AFC), it is considerate as a fuzzy variable.This gain is adapted as a function of the voltage error and its variation.The comparative at PI controller study, shows that the adaptive fuzzy controller can be enhance the performances the DC voltage control at various operating.Experimental results validate the design methodology. Active power filter (APF) performance is entirely dependent on capacitor voltage. DC voltage optimization is one of the key aspects in harmonics compensation. This paper presents an experimental comparative study of new adaptive fuzzy controller (AFC) and proportional integral (PI) regulator, applied to regulate the DC bus voltage of three phase shunt APF. The proposed AFC for APF, consist to adapt the output gain of this controller at every situation of the system as a function of the voltage error and its variation. The algorithm used to identify the reference currents is based on the Self Tuning Filter (STF). The firing pulses of the insulated-gate bipolar transistors (IGBTs) inverter are generated using a hysteresis current controller; which is implemented on an analog card. Finally, the above study, under steady state and transient conditions, is illustrated with signal-flow graphs and corresponding analysis. This study was verified by experimental tests on hardware prototype based on dSPACE-1104.

A Three-Phase Frequency-Adaptive Phase-Locked Loop for Independent Single-Phase Operation

Abstract: This letter proposes a phase-locked loop (PLL) able to operate as an independent single-phase PLL in the context of three-phase systems. Its key advantage is that the extracted information allows the independent control of both the active and reactive powers for each phase. The proposed PLL utilizes moving average filters and, hence, remains robust under unbalanced and highly distorted voltages. A frequency estimator is also presented and incorporated in the PLL angle detector path to make it frequency adaptive. The performance of the proposed PLL is verified experimentally and results for frequency change, phase-angle jump, and unbalanced voltage sag are reported as a confirmation of its potential.