In această lucrare sunt prezentate principiile de funcţionare pentru câteva structuri elementare de choppere de tensiune alternativă. Datorită avantajelor lor, acestea pot fi utilizate într-un număr mare de aplicaţii industriale. Sunt prezentate două tipuri de aplicaţii. Prima aplicaţie o reprezintă stabilizatoarele moderne de tensiune obţinute prin asocierea structurilor elementare cu transfor...

A novel online capacitance estimation method for a DC-link capacitor in a three-phase AC/DC/AC PWM converter is prepared. At no load, a controlled AC current with a lower frequency than the line frequency is injected into the input side, which then causes AC voltage ripples at the DC output side. By extracting the AC voltage and current components on the DC output side using digital filters, th...

this paper presents novel active filter for mitigation electromagnetic interference (emi) and other adverse effects of pulse width modulation (pwm) inverter-fed ac motor system. an active filter proposed and devised for this system is characterized by sophisticated connection of two small separate filters, capable of mitigating all the adverse effects. this paper provides high frequency models ...

Induction motors are widely employed in a variety of sectors, from household gadgets to industrial machinery. This mandates the deployment an effective and safe speed control device. may also run either direction, which is beneficial applications. The Motor Speed Direction Controller Project designed regulate induction motor's direction. on straight AC lines, amount power they receive determine...

The objective is to develop a fault diagnose scheme for MOSFET’s open switch faults for PWM voltage source inverter (PWM-VSI) motor drives. Here system monitors line to line voltage as well as switching signals nevertheless the triggering time of MOSFET, under both healthy and faulty conditions. So the measurement of line to line voltage is taken which gives the information about switching stat...

The aim of study of this paper is design and implementation of a simple and efficient soft switched Pulse Width Modulation (PWM) for three-phase induction motor drives. Soft-switching techniques have gained popularity in recent times because they offer many advantages over hard-switched Pulse Width Modulated inverters such as higher efficiency, higher power density and better performances. The ...

Algorithms of space-vector-based synchronized pulsewidth modulation (PWM) have been applied for control of dual-inverter fed open-end winding induction motor drives supplied by two isolated dc-sources with non-equal voltages. Results of modeling and simulation of these systems proved the fact, that techniques of synchronized PWM provide continuous phase voltage symmetry (quarter-wave symmetry, ...

This paper provides analytical and graphical methods for the study, performance evaluation, and design of the modern carrier-based pulsewidth modulators (PWM’s), which are widely employed in PWM voltage-source inverter (VSI) drives. Simple techniques for generating the modulation waves of the high-performance PWM methods are described. The two most important modulator characteristics—the curren...

The researches on direct AC-AC converters have been an important field. The DC-modulated method, which was used in DC-DC converters before, is used in AC-AC converters to realize a direct AC-AC converting now. The traditional control method regulates the output by adjusting the duty ratio. Its’ core is the PWM technology. In this paper, the variable structure control (VSC) strategy was utilized...