Proposed Wind Energy Conversion System Research Articles

Wind-driven SEIG supplying DC microgrid through a single-stage power converter

Nowadays, there is an increased emphasis on utilizing the renewable energy sources and selection of suitable power converters for supplying dc microgrid. Among the various renewable energy sources, wind energy stands first in terms of installed capacity. So, an attempt is made in this paper for supplying dc microgrid utilizing wind energy. A self-excited induction generator has been used in the proposed wind energy conversion system (WECS). A single-stage power converter, namely, semi-converter is connected between the SEIG and dc grid terminals for closed-loop control of the proposed system. A perturb and observe (P&O) based maximum power point tracking (MPPT) algorithm has been developed and implemented using a dsPIC30F4011 digital controller. In this MPPT algorithm, the firing angle of the converter is adjusted by continuously monitoring the dc grid current for a given wind velocity. For analyzing the proposed system, a MATLAB/Simulink model has been developed by selecting the various components starting from wind-turbine model to the power converter supplying dc microgrid. Successful working of the proposed WECS has also been shown through experimental results obtained on a prototype model developed in the laboratory.

Current Harmonics Reduction using Hysteresis Current Controller (HCC) for a Wind Driven Self-Excited Induction Generator Drives

We report a hysteresis current controller which is used to reduce current harmonics in the wind powered SEIG system. The proposed wind energy conversion system can be modelled and the parameters are verified under the varying wind speed ranges. The overall efficiency of the system can be affected from non-linear inputs and the selection of controllers for harmonic reductions. The controller is used to control the hysteresis band in the current ripple and produced required output voltage. Hysteresis current controller is modelled and the current harmonic interruption is reduced for the wind energy system applications. The system components like Wind Driven SEIG, Rectifier and Hysteresis Current Controller are modeled using MATLAB/Simulink and the experimental results are verified.

Direct‐drive low‐speed wind energy conversion system incorporating axial‐type permanent magnet generator and Z ‐source inverter with sensorless maximum power point tracking controller

With the ever increasing concern on environmental pollution and energy crisis, generation of power from wind is developing very fast. In the proposed wind energy conversion system (WECS), a variable-speed wind turbine, axial-type permanent magnet generator (PMG), Z-source inverter (ZSI) and sensorless maximum power point tracking (MPPT) controller are included. Although the conventional-type induction generator has the advantage of robust construction and maintenance-free operation, it has drawbacks like low-power factor and need for an ac excitation source which is overcome by the PMG. To obtain fixed voltage and frequency, PMG-generated voltage is fed to power converters. Conventionally the three stages of power conversion consist of rectifier, boost chopper and pulse-width-modulated inverter which reduce the efficiency, power quality and reliability of the overall WECS. To overcome these barriers of conventional system a two-stage-based direct-drive WECS is proposed. The maximum power point for each speed is traced using sensorless MPPT controller, which estimates the rotor speed, by using a simple sensorless speed estimator which is given as the input to the MPPT controller. The proposed sensorless MPPT controller for direct-drive WECS along with the ZSI is simulated in MATLAB/SIMULINK and the results are compared with experimental setup.

An integrated control approach for standalone operation of a hybridised wind turbine generating system with maximum power extraction capability

This paper presents a novel configuration of a hybrid wind generating system which can be used as a remote area power supply (RAPS) system. The proposed wind energy conversion system consists of a doubly-fed induction generator (DFIG) and a permanent magnet synchronous generator (PMSG) where the latter is connected to the DC bus of the DFIG generator. In addition, a battery storage system is also incorporated into the DC bus to address the demand-generation mismatch. Control strategies for individual system components of the RAPS system are designed with a view to achieve an acceptable level of voltage and frequency regulation while extracting the maximum power from wind. The performance of the proposed RAPS system is investigated in terms of voltage and frequency regulation capability under changing wind and variable load conditions.

Grid Support with Variable Speed Wind Energy System and Battery Storage for Power Quality

The proposed wind energy conversion system with battery energy storage is used to exchange the controllable real and reactive power in the grid and to maintain the power quality norms as per International Electro-technical commission IEC-61400-21 at the point of common coupling. The generated wind power can be extracted under varying wind speed and can be stored in the batteries at low power demand hours. In this scheme, inverter control is executed with hysteresis current control mode to achieve the faster dynamic switchover for the support of grid. The combinations of battery storage with wind energy generation system, which will synthesizes the output waveform by injecting or absorbing reactive power and enable the real power flow required by the load. The system reduces the burden on the conventional source and utilizes WEGS and battery storage power under load constraints. The system provides rapid response to support the grid. The scheme can also be operated as a stand-alone system in case of grid failure like a uninterrupted power supply. The system is simulated in MATLAB and results are presented.