The power take-off mechanism of the oscillating water column based Indian wave energy plant is based on an impulse turbine-permanent magnet synchronous generator (PMSG) set. The MATLAB based simulation of the dynamic model of this power module, considering the plant's operation on the stand-alone mode, is developed incorporating a machine variable model for the PMSG used. It is shown that the energy efficiency of the impulse turbine can be substantially increased by adjusting the load resistance dynamically, as a function of the input differential pressure.

V. Jayashankar

Columns (structural)

Electric generators

Engines

Hydraulic turbines

Magnets

MATLAB

POWER TAKEOFFS

Synchronous generators

Turbines

WAVE ENERGY CONVERSION

WAVE POWER

Differential pressures

Efficiency improvement

IMPULSE TURBINE

IMPULSE TURBINES

Load resistances

OSCILLATING WATER COLUMN

OSCILLATING WATER COLUMNS

PERMANENT MAGNET SYNCHRONOUS GENERATORS

PLANT'S OPERATIONS

POWER MODULES

transient model

VARIABLE MODELS

WAVE ENERGIES

Energy efficiency

Alternative energy

Computer simulation

power plant

turbine

WATER COLUMN

Wave energy

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Enhancing the energy efficiency of the impulse turbine of a wave energy plant

International Journal of Sustainable Energy

Ocean wave energy has not yet gained popularity as a renewable energy source because of intermittent nature of available wave power. Still deriving a constant power at the output, requires embedding of energy storage devices of sufficient capacity into the wave energy converter. A Permanent Magnet Synchronous Generator(PMSG) based adjustable speed energy extracting scheme is employed so as to operate the air-turbine close to its Maximum Power Point operation. The variable voltage variable frequency AC supply generated by the PMSG is processed by a diode bridge- VSI cascade, to generate usable regulated AC supply. In order to estimate the energy storage requirement, especially under different climatic conditions, the emulation of the DC bus voltage dynamics is required. Considering typical wave height, wave period and differential pressure/ wave power variation applicable to the site of Indian wave energy plant, off-line computation of the DC bus voltage dynamics is carried out using MATLAB based transient model of the complete wave energy converter. Finally, the results obtained from the emulation carried out employing micro-controller P89V51RD2 are given. © 2011 IEEE.

2011 International Conference on Emerging Trends in Electrical and Computer Technology, ICETECT 2011

Micro-controller based emulation of a wave energy converter

Oscillating Water Column based wave energy plants convert wave energy into low pressure pnuematic power in the form of bi-directional air flows. Air turbines which are capable of rotating uni-directionally in bi-directional air flow, otherwise also known as self-rectifying turbines, are used to extract mechanical shaft power which is further converted into electrical power by a generator. This paper reviews the state of the art in self-rectifying impulse air turbines. New results on optimum parameters for the fixed-guide-vane impulse turbine are also presented. Starting characteristics and conversion efficiencies of two types of impulse turbines are compared with the well known Wells turbine. © 2001 Elsevier Science Ltd. All rights reserved.

Journal	International Journal of Sustainable Energy
ISSN	14786451
Open Access	No