PWM rectifier

About: PWM rectifier is a research topic. Over the lifetime, 2254 publications have been published within this topic receiving 25614 citations.

Fault tolerant control of redundant topology of PWM AC-DC-AC converter supplying an electromechanical drive

Abstract: Purpose of this paper is the study by simulation of a fault tolerant control with pulse large modulation (PWM) AC-DC-AC converter supplying a three-phase rotor field oriented induction motor. The back to back converter, is supplied with three-phase network and composed of a PWM rectifier and a voltage source inverter. Fault tolerant topology of AC-DC-AC converter that with redundancy have been studied and associated with affective and fast method of fault detection and compensation to guarantee the continuity of service, in the presence of a possible open circuit failure on the level of one of their legs. Although of the presence of open circuit on the level of the converter legs, the obtained simulation results show that it is possible to maintain the good performance of the drive.

Motor drive pwm rectifier having modulation scheme selector

Abstract: A motor drive PWM rectifier includes a control section which generates the PWM signal in accordance with either a three-phase modulation scheme or a two-phase modulation scheme in which a PWM voltage command for one phase selected from among three phases each constituting the PWM voltage command in the three-phase modulation scheme is set and held at a level equivalent to a maximum value or minimum value of the PWM carrier and in which a PWM voltage command for the other two phases created by also applying an offset, required to achieve the setting, to the other two phases, a detecting section which detects three-phase AC current and outputs a detected current value, and a selecting section which selects the two-phase modulation scheme when the detected current value is larger than a first threshold value but smaller than a second threshold value, and otherwise selects the three-phase modulation scheme.

Analysis and Control of the Output Instantaneous Power for Three Phase PWM Boost Rectifier Under Unbalanced Supply Voltage Conditions

Abstract: This paper proposes a new method to analyze the output instantaneous power of the three phase PWM boost rectifier under unbalanced supply voltage conditions An analytical expression for the output instantaneous power has been derived and presented, which provides the link between the output dc linkage voltage and the instantaneous output power Based on the mathematical model of the three phase PWM rectifier in the rotating synchronous frame, the physical concept of the output instantaneous power has been explained from the analytical point of view A direct relationship between the dc link voltage ripples and the second harmonic component in the instantaneous output power has been derived A simple cascaded PI control scheme has been developed for the dc output voltage control The controller ensures that the dc link voltage is maintained constant and the supply side power factor is kept close to unity under the unbalanced supply voltage operating conditions Simulation and experimental test results are provided on a 16 kVA laboratory based PWM rectifier to validate the proposed analysis and control scheme

Analysis of Single Phase PWM Rectifier for Different Applications

Abstract: This research work investigates the various applications of a PWM rectifier based on its input power factor. Most of the cases, the papers describe the operation of the rectifier used for unity power factor (UPF) operation. Beside this mode of operation, this paper compiles the application of the rectifier as STATCOM also, where the rectifier deals only with reactive power exchange. In this work, the controller is implemented by inserting a loop for reference input of phase angle which will be compared with the actual one, so that user can operate the rectifier at any power factor. Some basic formulae are derived for the input current, active power and reactive power based on which the control circuit is to be designed. Here two Proportional–Integral (PI) controllers are used. A brief description of tuning these two PI controllers is incorporated in this paper. Also some calculations are given to determine the harmonic factors of the input line current from which it is found that the rectifier when operated in each mode operation, the order of the harmonics are very low.

Asymmetrical Cascaded Three-Phase AC–DC Converters With Injection Transformers

Abstract: In this paper, three generalized configurations of three-phase pulsewidth modulated (PWM) rectifiers are presented. They are composed of cascaded cells, each formed by a three-phase bridge of switching devices and a three-phase transformer to cascade the cells and isolate the load from the power source. One configuration is bidirectional, whereas the other two are unidirectional alternatives that replace power switches for diodes in some legs. The turns ratios of transformers from each cell are designed in order to provide the required gain and number of levels in the inverted multilevel voltage, enhancing power quality while attending requirements for proper operation in each case. Configurations with two and three cells are compared by means of simulations between themselves and with three conventional three-phase PWM rectifiers: the two-level insulated gate bipolar transistor bridge and the multilevel neutral point clamped (NPC) bridge and NPC H-bridge. Many degrees of asymmetry between the transformers in each cell, determined by the turns ratios, are considered to evaluate their impact on the topologies with relation to performance and cost. It is shown that proposed multilevel rectifiers present lower harmonic distortion, semiconductor losses, and switching stress, and some options with intermediate asymmetry are considered as good alternatives to the most asymmetrical cases. Experimental results are also provided for configurations with two cells, to demonstrate their lower harmonic distortion and power losses compared to the conventional isolated two-level PWM rectifier.