Sachin Tiwari

A Comparative Study of Fixed Speed and Variable Speed Wind Energy Conversion Systems Feeding the Grid

In the early development of the wind energy, the majority of the wind turbines have been operated at constant speed. Subsequently, the number of variable-speed wind turbines installed in wind farms has increased. In this paper, a comparative study of fixed and variable speed wind turbines incorporating squirrel cage induction generator take into consideration all realistic constraints has been presented. These two systems are modeled and simulated using Matlab. The variable speed induction generator system has been modeled using power electronic converters and vector control technology combined with peak power extraction technique (PPET) enabling the system to run at the most optimal speed. The results are presented for 55 kW induction generator, and variable speed operation is highlighted as preferred mode of operation.

Soft Computing Techniques for Static Series Voltage Regulator of Self Excited Induction Generator

This paper deal with soft computing techniques such as artificial neural network (ANN), fuzzy logic controller (FLC) and proportional-integral (PI)-based static series voltage regulator (SSVR) for constant speed prime mover driven self excited induction generator (SEIG) feeding three phases linear and nonlinear loads. The constant speed prime mover such as biogas, biomass and gas-turbine driven standalone generating system has problem of poor voltage regulation. The SSVR is injects series voltage in to system to maintain constant source and load voltage with power quality improvement of source and load current. The SSVR is modeled using insulated gate bipolar junction transistor (IGBT)-based voltage controlled-voltage source converter (VC-VSC) with self supported DC bus. The A 7.5 kW, 415 V, 50 Hz asynchronous machine with voltage regulator and loads are designed, modeled and simulated in MATLAB environment. Simulated results are presented capability of an SEIG system with ANN, fuzzy and PI-based SSVR and their comparison.

Comparative analysis of three phase AC-DC controlled multi pulse converter

This paper addresses the comparative study of three phase controlled multi pulse converters used to drive the biomass, gas turbine, hydro, diesel and wind system based power plant which are the viable sources of renewable energy having different nature in respect of speed and voltage This paper approaches the input current shaping of controlled rectifier using multipulse current shaping concept. The developed mathematical model of multi pulse converters emulates the behavior of various multi pulse current shaping methods. The mathematical model is capable of replicating the operating behavior for converters with any number of rectifiers; 6-, 12-, 18-, 24-, 36-, and 48-pulse thyristor converters. The comparative study given in this paper covers cases on controlled rectifiers. As part of the simulated results on converter performance, data related to the Total Harmonic Distortion (THD), ripple in the output voltage, and power efficiency is given.

Series active filter based voltage controller for an isolated asynchronous generator

This paper presents an investigation of series active filter (SAF) based voltage controller to control the voltage of constant speed prime mover driven isolated asynchronous generator for supplying three phase resistive and inductive load. The constant speed prime mover like diesel, biomass, gas turbine etc. In such type of scheme whole generating system isolated from the grid and supply electrical power directly to the consumers. The controller is modeled using IGBT (Insulated Gate Bipolar Junction Transistor) based voltage controlled voltage source converter (VCVSC) with self supported DC bus. The SAF inject a voltage in series with system voltage. The 7.5Kw, 415V, 50Hz asynchronous generator (self exited induction generator (SEIG)) based generating system with SAF is modeled and simulated in MATLAB along with Simulink and power system block set (PSB) toolbox. The simulated results are presented to demonstrate the capability of asynchronous generator system with voltage controller for feeding varying consumer load.

A new topology of transistor clamped 5-level H-Bridge multilevel inverter with voltage boosting capacity

Multilevel converters are well suited for medium and high power applications because of its characteristic of synthesizing a sinusoidal voltage on several DC levels. They give good quality output resulting with lower harmonic distortion in the output and lower commutation losses. The main disadvantage is their complex circuit configurations, requiring a great number of power devices and passive components, and a complex control circuitry. A new topology of multilevel inverter for 5-level using the Conventional H-Bridge is proposed in this paper. The proposed topology is referred as new TCHB has the feature like boost output voltage capability along with capacitor voltage balancing. The proposed multilevel inverter uses four auxillary switches and transistor clamped H-bridge (TCHB) with an bidirectional switch. The single cell of conventional H-bridge produces three-level output voltage similar to input DC voltage but the single cell of proposed topology produces five-level output with output voltage double the input DC voltage. The proposed new TCHB and old TCHB 5-level inverter are modeled and simulated on matlab/simulink and compared in terms of the output voltage, total harmonic distortion (THD), No. of switching devices used etc. From the results the proposed inverter provides more output voltage with less harmonics in the output voltage.

Artificial neural network based series active power filter for self excited induction generator

This paper presented ANN (Artificial Neural Network) based SAPF (series active power filter) for voltage control and power quality improvement of constant speed prime mover driven self excited induction generator. The constant speed prime mover such as biogas, biomass, gas-turbine, and diesel turbine driven standalone generating system has problem of poor voltage regulation and power quality with linear and nonlinear load conditions. The SAPF is inject series voltage between source and load to maintain constant source and load voltage with power quality improvement of source and load current. The SAPF is modeled using Insulated Gate Bipolar Junction Transistor based Voltage Source Converter with self supported DC bus. A 7.5 kW, 415 V, and 50 Hz asynchronous machine with SAPF and loads are designed, modeled, and simulated in MATLAB environment. The performance of ANN based SAPF is also compared with a Proportional Integral controller based SAPF.

Artificial neural network based controller for active power line conditioner

Proliferation of non-linear loads resulted in the problems of harmonics, unbalancing, poor power factor. To overcome this active power line conditioner (APLC) is used. In this paper, an artificial neural network (ANN) based controller for active power line conditioner is presented, in which feedforward neural network, trained by levenberg marquardt (LM) algorithm is implemented for generating reference current and pulses to inverter. The simulation results by using MATLAB/SIMULINK of both the conventional and ANN based controller model are discussed. The neutral current has been reduced to maintain system balance.

Different topology of hybrid wind-fuel cell power generation

This paper include the different type of wind power plant (WPP) are connected with fuel cells. Due to the fluctuating nature of wind power, another energy source should be integrated with the wind turbine to ensure reliable and efficient operation of the power system. In order to solve this problem, fuel cell may be integrated with the wind turbine. The different types of generators are use in WPP like induction generator, synchronous generator and DC generator. The WPP along with the combination of proton exchange merman (PEM) fuel cell has attracted increasing attention in remote area due to low operating temperature, rapid start-up, high power density & simplicity in operation. Hence hybrid wind-fuel cell system increases the efficiency & extends the duration of the available of power. the purpose of this paper to introduce different type of topology of hybrid wind-fuel cell power generation.