Control Strategies for Quad-Inverter Multiphase-Multilevel AC Drives in Post-Fault Condition

was derived and a relationship between Vinv and Vc was obtained (see Fig. 2). Applying voltage balance

The parameters of this controller (PI- 1) can be decreased during the voltage sag in order to improve the performance of the proposed method.

The impact of the proposed sequences has been simulated for 0.4 modulation index with a 0.5 lagging power factor load (power factor angle 60°). The simulation setup consists of the following software: 1) MATLAB/Simulink – used to implement the modulation strategies and switching sequences, and 2) PSIM – used to simulate the T-NPC inverter running with an R-L load and to provide conduction and switching losses of each switch. The inverter switching pulses were generated within Simulink and were fed to PSIM through sim-coupler module which provides a link between PSIM and simulink for the purpose of co-simulation [29].

The innovative inverter technology produces safe, smooth power, protecting your sensitive electronics (computers, smartphones, etc.) from damage.

The advantages of Field Oriented Control are transformation of a complex and coupled AC model into a simple linear system , independent control of torque and flux, fast dynamic response , good transient and steady state performance ,high torque and low current at start up and high Efficiency[2].

Abstract: The area of the multiphase motor has experienced a significant growth in last decade numerous interesting development have been reported in the literature in this chain this paper is an attempt to mathematically model both three phase and six-phase induction motor for comparison of their characteristics. Using this mathematical modeling a Simulink model is created whose results shows that the six-phase induction motor can sustain more than four times the torque that can be sustained by three phase induction motor of same design parameters. The six-phase motor is better not just in torque handling capacity but it also has inherent advantages of the multiphase induction motor.

This thesis deals with the design and analysis of control system structures for electric drives equipped with permanent magnet synchronous machines (PMSM) in automotive application.With the increasing popularity of multi-level inverters, the room for improvement of the performance of voltage source inverters has continuously been tested for various applications. The rapid development of high switching frequency power electronics in the past decade leads towards wider application of voltage source inverters in AC power generation. Therefore, this prompts the need for a modulation technique with less total harmonic distortion, fewer switching losses, and wider linear modulation range.The present thesis highlights the comparison of the conventional two-level inverter and the three-level diode clamped inverters for the application in automotive industry.

Abstract—This assignment is based on the CIGRE HVDC benchmark system and deals with understanding and simulating this system in PSCAD/EMTDC. The focus is on the rectifier station of the CIGRE system which has been idealized and simulated in PSCAD. The AC-side real and reactive power and DC-side power corresponding to the firing angle from 0 to 180 degrees has been calculated and plotted. Furthermore, the power balance between the AC and DC-side of the converter has been explained. Index Terms— Converter, EMTDC, HVDC, PSCAD, Real power,

Discrimination between inrush currents and internal faults has long been known as a challenging power transformer protection problem. Otherwise, inrush currents contain large second harmonic component compared to internal faults, conventional transformer

DBR followed by a filter and an isolated zeta converter. The filter is designed to avoid any switching ripple in the DBR and thesupply system. An isolated zeta converter is designed to operate in DCM to act as an inherent power factor corrector. This combinationof DBR and PFC converter is used to feed a BLDC motor drive via a three-phase VSI as shown in Fig. 1. The dc link voltage of the VSI is controlled by varying the duty ratio of the PWM pulses of PFC converter switch. However, VSI is operated in a low frequency switching to achieve an electronic commutation of BLDC motor for reduced switching losses. A single voltage sensor is used at the front-end converter for the control of dc link voltage for speed control of BLDC motor. The proposed drive is designed and its performance is validated on a developed prototype for improved power quality at ac mains for a wide range of speed control and supply voltage variations.

For emolument of current harmonics (if any), the instantaneous resoluteness of different active and reactive powers is utilized - the active and reactive powers are computed utilizing p-q theory. No restrictions are imposed on the voltage or current wave forms, and it can be applied to three-phase systems with or without a neutral wire for three-phase generic voltage and current wave forms. Thus, it is valid not only in steady state, but withal in transient states.

Multilevel inverters have ability to generate low switching frequency high quality output waveforms with several high voltages and high power applications. The general structure of the multilevel converter to synthesize a

The objective of the study is to develop a realizable inverter design that would be reliable, cost effective, efficient, and maintainable. The inverter is to be powered from a 12Vdc/40Ah battery source and it is to generate a 220VAC/50Hz with a power rating 500VA. Other objectives of the study include:

Index Terms – Unified Power Quality Conditioner, Active Power Filter, hysteresis control, voltage and current unbalance.

2.2.1 Comparison of simulation results of three level & five level H-bridge multilevel inverter by mamta N. kokate