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This paper presents a new method for power factor correction with low cost drives. Power factor control is a major role in the improvement of power system stability. Many of the existing systems are expensive and difficult to manufacturer. Nowadays many of the converters have no input power factor correction circuits. The effect of power factor correction circuit is used to eliminate the harmonics present in the system. This type of power factor correction circuit is mostly used in the Switched Reluctance Motor controller drive. Fixed capacitor systems are always leading power factor under at any load conditions. This is unhealthy for installations of power system. The proposed embedded system drive is used to reduce the cost of the equipment and increase the efficiency of the system. Experimental results of the proposed systems are included. It is better choice for effective cost process and energy savings.

The insulator is the major constituents in any electrical transmission and distribution system. Pollution is one of the most significant phenomena, which determine the performance of the insulator and also dissembles the entire electrical power systems. The pollution performance is a diplomatic problem with worldwide, which depend upon the climatic condition. The purpose of high voltage insulator is to withstand electrical stress due to high electric field intensity. A new swing antipollution coating is enforced to improve the flashover voltage. In this work, pollution performance test acquired to the 11kV post type ceramic insulator polluted by the coastal thermal power plant without coating and with Epoxy Resin coating. The experiments have been carried out in both categories (without and with coating) adopt in IEC standard. In simulation modeling, FOV (Flash over voltage) and NSDD (Non-soluble deposit density) are predicted and then compared with computational real value through Artificial neural network in simulation software packages.

The twin unidirectional turbine topology was recently proposed with the promise of very significant improvements in the energy capture in Oscillating Water Column (OWC) based wave energy plants. Here, we present the initial results of the experimental validation of the twin unidirectional impulse turbine topology. A scale model of the concept was built and tested using simulated bidirectional flow. The model consists of two 165 mm impulse turbines each individually coupled to 375 W grid connected induction machines. An oscillatory flow test rig was used to simulate bidirectional flow to test the model. The results of the experiments validate the concept of the twin turbine configuration. The proposed topology utilizes no moving parts and achieves more than 50% efficiency over a broad range of flow coefficients. A comparison with other competing turbines (viz, a twin Wells' turbine, a linked guide vane impulse turbine and a fixed guide vane impulse turbine) is done, based on actual measurements in the Indian wave energy plant. The results from the experiments are scaled to evaluate the design features of a 50 GWh wave energy plant. � 2010 Elsevier Ltd.

Experimental results from near shore bottom standing OWC based wave energy plants in Japan and India have now been available for about a decade. Historically the weakest link in the conversion efficiency of OWC based wave energy plants built so far has been the bidirectional turbine. This is possibly because a single turbine has been required to deliver power when the plant is exposed to random incident wave excitation varying by a factor of 10. A new topology that uses twin unidirectional turbines (which features a high efficiency spanning a broad range) is proposed. Using the Indian Wave Energy plant as a case study, it is shown that the power output from such a module considerably exceeds existing optimal configurations including those based on a fixed guide vane impulse turbine, linked guide vane impulse turbine or a Well's turbine. A wave to wire efficiency of the order of 50% over the incident range is shown to be feasible in a credible manner by showing the output at all stages of the conversion process. A frequency domain technique is used to compute the OWC efficiency and a time domain approach used for the power module with the turbine pressure being the pivotal variable. � 2008 Elsevier Ltd. All rights reserved.

The Indian wave energy plant is based on the Oscillating Water Column (OWC) principle at Vizhinjam, Kerala and has been a technology demonstration plant. A scheme was envisaged wherein the impulse turbine existing on the caisson is connected to a variable speed alternator to run a desalination plant as load. A methodology has been established to forecast the performance of the turbine, alternator, battery and inverter by means of a simulated wave profile and differential pressure. Actual testing of the scheme was carried out in the laboratory and the scheme was found to be successful. New control logic was introduced, whereby the desalination plant can be run using either the supply from wave power or, during low wave conditions, by electricity board supply or a diesel generator to ensure a continuous supply of fresh water. The scheme for running the reverse osmosis (RO) based desalination plant using wave power has thus been proved and the system has been successfully commissioned.

The deep sea corrosion of ferrous alloys that undergo uniform corrosion without forming a passive layer is related to the amount of dissolved oxygen available in the sea water. The preformance of some ferrous alloys at depths of 500, 1200, 3500, and 5100m in the Indian Ocean has been studied. The results of atomic absorption spectroscopy have revealed that the corrosion product present on mild steel coupons is FeOOH. The results of experiments in shallow water have shown that micro- and macrobiological growths play a significant role in the corrosion of ferrous materials. However, in deeper waters, the absence of macrofouling was evident, and corrosion was not related to any biological product but mainly to the electrochemical reaction of these alloys with sea water. The results of morphological studies by SEM on the surfaces of exposed specimens are also presented.

Ocean Thermal Energy Conversion (OTEC) utilizes the thermal gradient available in the ocean to operate a heat engine to produce work output. Even though the concept is simple and old for almost one century, recently it has gained momentum due to worldwide search for clean continuous energy sources to replace the fossil fuels. There are technological hurdles to overcome to tap the immense potential of OTEC. But still the technology is mature enough to establish commercial power plants. National Institute of Ocean Technology was involved in the design, development and demonstration of a 1 MW OTEC floating plant-the largest of its kind-in the Indian waters. This is to be commissioned 60 km south east of Tuticorin, South India where an ocean depth of 1200m available. The site surveys, computer analysis, model studies were done in 1999. The basic power cycle design Was completed within 4 months. The plant was integrated and stage qualification tests were carried out in 2000-02. The project is to be commissioned in January 2003. This paper is projecting the technological and economical aspects of the OTEC with an overview of the various pre-commissioning activities of the project.

Energy saving method is very important for manufacturing of motor industries. Since 65% of electrical energy is consumed by electrical motors. Hence in this present work describes a new methodology to increase the efficiency of Switched Reluctance Motor (SRM). A new control circuit has been designed to improve the performance and efficiency of SRM. Modified controller is used to explain the energy savings of SRM. This proposed method is better than existing method. This method is also used to reduce the switching losses of SRM. Hence the cost of the drive system is reduced. Stored energy in off-going phase winding is once again used. Hence consumption of electrical energy of motor is reduced

A harbor oscillating water column wave-energy device has been selected for the Indian pilot wave-energy program. The site has a water depth of about 12 m and an average annual wave-power potential of 13 kW/m. Such sites are attractive locations for fishing breakwaters. Due to the relatively low power potential, these oscillating water column devices are intended to be modules of a multifunctional breakwater. The present paper highlights the results of the scale-model experiments carried out on a prototype wave-energy caisson.

A twin unidirectional turbine topology has been proposed as a power module for an OWC based wave energy plant. It has no valves or moving parts and demonstrates high efficiency over a broad range of flow coefficients. Scaling laws show that a turbine of 2.6 m diameter is sufficient to achieve a power rating of 2 MW, Thirty one such modules can be used to produce an annual output of 50 GWh.

The PCI Special Interest Group (PCI-SIG), developers of the PCI and PCI Express specifications, released the PCI Express External Cabling 1.0 Specification in February 2007 to extend PCI Express "outside the box." Cabled PCI Express is a high- performance cabled serial bus to interconnect system components. The following paper examines the technology behind cabled PCI Express and the technical specifications needed to connect devices with independent PCI domains.

The PCI special interest group (PCI-SIG), developers of the PCI and PCI express specifications, released the PCI express external cabling 1.0 specification in February 2007 to extend PCI express "outside the box." Cabled PCI express is a high-performance cabled serial bus to interconnect system components. The following sections examine the technology behind cabled PCI express, as well as current and future application needs in measurement and automation systems.

Ocean Thermal Energy Conversion (OTEC) utilizes the thermal gradient available in the ocean to operate a heat engine to produce work output. The technology is mature enough to establish commercial power plants. India is geographically well placed as far as the potential is concerned with /spl Delta/T above 20 degC between sea surface water and 1000 m depth throughout the year. Attractive locations suitable for land based as well as floating OTEC plants are available on the Indian coast and in the island groups in the Indian Ocean. Since 1998 the National Institute of Ocean Technology was involved in the design, development and demonstration of a 1 MW (gross) OTEC floating plant - the largest of its kind. This is to be commissioned south east of Tuticorin, South India where an ocean depth of 1200 m is available from 40 km off the main land. The computer analysis, model studies and site surveys were done in 1999. The basic power cycle design was completed within 4 months. The plant is based on the closed Rankine cycle with ammonia as the working fluid. The evaporators have a special steel coating on the ammonia side to enhance the nucleate boiling. An after condenser is introduced after laboratory studies to improve the power plant stability. A four-stage axial flow ammonia turbine was developed with a pressure ratio of 1.4. The plant was integrated on a floating barge with 3 moon pools acting as a sump for sea water intake and discharge. The cold water sump is having 14 m depth locked on the deck to provide enough NPSH for the cold water pumps. The stage quantification tests were carried out in January 2000 on sea water pumps at shallow waters and a turbine-generator unit with compressed nitrogen gas. The floating barge is to be moored with a single point mooring at 1200 m depth using the 1 m diameter HDPE pipe, which is the intake for the cold water. The power plant and sea water systems are ready and it is scheduled to be commissioned in August/September 2002. This paper is projecting the technological and economical aspects of the OTEC with an overview of the various studies and pre-commissioning tests carried out.

The wave energy group at the Indian Institute of Technology, Madras, India, in coordination with the National Institute of Ocean Technology, Madras has successfully installed a pilot wave energy plant of the oscillating water column (OWC) type, at Vizhinjam, on the west coast of India. The wave energy plant (WEP) consists of a concrete caisson OWC pneumatically driving a Wells type turbine. The turbine is mechanically coupled to an induction generator (IG). The stator of the IG is connected to the electrical grid of the Kerata State Electricity Board. This paper describes the control instrumentation and data acquisition aspects of the WEP. Simple data collected on the power module are also provided in the form of graphs.

Measurement of air velocity when flow is oscillating is required in ocean wave energy studies. A special type of self-rectifying air turbine called "Wells turbine", coupled with induction generator is used for converting the air column movement in a wave energy basin to electrical energy. So far no attempts have been made to study the air velocity variations into and out of the turbine at site. Some efforts for measurement of oscillating air column at laboratory using hot-wire anemometer have been reported. A novel probe, comprising miniature pressure transducers, for the measurement of air velocity variations into and out of the turbine, was designed and developed. The probe was first calibrated and tested at the laboratory before shifting to site for actual measurements. An unidirectional oscillating air flow facility was initially setup at the existing air flow laboratory, which has a variable speed blower as the prime mover. Oscillating flow was generated by a butterfly valve, operated through a function generator. Tests at a nominal frequency of 0.1 Hz and flow velocities upto 35 m/s were conducted. Accuracies of the order of /spl plusmn/2% were estimated for the probe.

As a part of the Wave Energy Program of the Ocean Engineering Centre, Indian Institute of Technology, Madras (India), theoretical and experimental investigations are in progress to obtain the necessary data to design an optimum Oscillating Water Column (OWC) Device for exploitation of Wave Energy. This paper presents the experimental results on two different geometries of the device. The results show the influence of the ratio 'Wave Length to the Device Length and the damping on the device efficiency indicated by the capture factor.