Low-Cost (PM Less) Wide-Speed-Range-Operation Generators

This chapter presents a novel dual stator-winding induction generator (DSWIG) system for wind power generation, and an optimal scheme to decrease the capacity of static excitation converter (SEC) is also given. The main result is represented by the finding that reactive excitation power released by the excitation capacitor and SEC is not only correlated to generator parameters, speed range, and load but also affected by wind turbine power curve. This chapter also investigates the optimal excitation capacitor selection process. Considering the objective of minimizing the capacity of SEC, several methods are tested here to identify an appropriate excitation capacitor value. Using the general d-q model in the stator-voltage-orientation synchronous frame of the DSWIG control algorithm and model of SEC, a decoupling control strategy using the space vector modulation (SVM) is determined for the six-phase DSWIG. Based on the obtained models, the computer simulation and experimental investigations of a test prototype orated at 18 kW with six stator phases and three-phase wound rotor DSWIG wind power system were carried out to validate the optimal solution for the system The matching results (simulation and teststand measurements) demonstrate the correctness and effectiveness of this optimization scheme

Lightweight High-Efficiency Power Train Propulsion with Axial- Flux Machines for Electric or Hybrid Vehicles

The aim of this chapter is to present a new type of powertrain with dimensions and low weight, for vehicles with reduced carbon emissions, which have an axial synchronous machine with one stator and two rotor, with static converter that is simple and inexpensive, a broadcast transmission system using an electric differential, with the control of the two rotors so that they can operate as motor/generator, at the same rotational direction or in opposite directions, at the same speed value, at slightly different speeds or at much different speeds by using an original dual vector control with operating on dual frequency. This is a major concern of hybrid and electric vehicle manufacturers. Expected results: a lighter power train with 20% and an increase in 5% of electric drive efficiency, low inertia rotor at high speed, a compact electric drive system with high torque and simple control, intelligent energy management system with a new vision of technological and innovation development, and equal importance of environment protection. The electrical machines for hybrid (HEV) or electric (EV) drives include a variety of different topologies. According to outcomes of literature survey, induction machines alongside synchronous machines take the major place in HEV or EV power trains

Fractional kVA Rating PWM Converter Doubly Fed Variable Speed Electric Generator Systems:An Overview in 2020

Variable speed generator systems (VSGs) are at work in the now 600 GW installed wind power plants (parks). Also, they are used as vehicular and on ground stand-alone generators. VSGs imply full kVA rating PWM converters in permanent magnet (PM) or in electrically excited synchronous or in cage rotor inductance generators. But, to reduce cost in absence of PMs at a reasonable initial cost (weight) and efficiency, the fractional kVA PWM converter doubly fed induction generators (DFIG) cover now about 50% of all installed power in wind generators. The present paper reviews recent progress in DFIG and various forms of brushless DFGs (doubly fed generators) characterized in terms of topology, design, performance and advanced control for healthy and faulty load conditions in the hope of inspiring new, hopefully ground breakings, progress for wind and hydro energy conversion and in vehicular and on the ground stand-alone generator applications

Control System for Producing Electricity with Dual Stator Winding Cage-Rotor Induction Generator

This paper will present the key design equations and control design model of the Dual Stator Winding Cage-Rotor Induction Generator (DSWIG) to achieve wide-speed-range operation with reduced capacity of the static power controller for low power wind or hydro applications. The proposed induction generator consists of a standard squirrel-cage rotor and a stator with two separate windings wound for a similar number of poles. Moreover, the system control strategy using the stator flux orientation is consequently proposed. The aim of the paper is to emphasize that the low speed induction generators with power electronic converters represent a realistic and useful solution for direct drive power applications

Hardware in the Loop Wind Turbine Emulator

The paper presents a "hardware in the loop" emulator for a wind turbine system, used to tune and test in the laboratory the generator and the associate power electronics and control. The emulator includes: a Alatlab/Simulink model of the wind turbine, an a.c. drive with direct torque control (the wind turbine equivalent) coupled with the real generator and the corresponding load. Digital simulations compared with experimental results arc presented to validate the wind turbine emulator