V. Rajini

Park's vector approach for online fault diagnosis of induction motor

In this paper, the induction motor is modelled in stationary reference frame using the equations derived from the equivalent circuit model of the stationary reference frame. After implementing the model, it is analysed under healthy and faulty condition. The considered faulty conditions of the induction motor include the stator and rotor fault. Any single phasing situation creates the stator fault that may result in opening and shorting of one or more phase winding. In this work the modelled induction motor is modified for analysing the open circuit fault of the stator phase windings and the result are compared using the using the voltage pattern and the current pattern obtained using Parks vector approach. The results are compared to give the best solution in stator fault diagnosis. The broken bar fault is introduced in the rotor by making some modifications in the model and the current pattern obtained using Parks vector approach is analysed with the difference in the pattern produced during the healthy condition. Finally, both the faults are introduced in the model and the result is analysed using Parks vector approach.

A new green energy interface for telecommunications

ABSTRACT Providing electricity to telecom tower can be realised by hybrid green energy systems than extending a power line from grid. For a hybrid energy system, it is important to develop a converter to integrate different power sources and storage elements. Conventional systems use an individual converter for individual source thus leading to a relatively complex configuration, larger component count and reduced system efficiency. To address these issues green energy interface (GEI) converter is used. In this paper, a detailed component wise analysis and performance comparison between conventional and GEI converter using Matlab/Simulink is presented. GEI converter has linear and non-linear components. So, small signal model based on state space averaged model of the GEI topology is obtained. A lab level prototype for the GEI converter with programmable interface controller is implemented and tested under various input conditions to study the performance of the converter during seasonal changes. The simulation and experimental results showed that effective operation and control strategy of the hybrid power supply system. Abbreviations: BTS: base transceiver station; MSC: mobile switching centre; BSC: base station controller; CAPEX: capital expenditure; OPEX: operational expenditure; GEI: green energy interface

Analysis of efficient methods of water production using renewable energy based reverse osmosis desalination process and its applications in India

M are essential sources of freshwater for our world, but their role in global water resources could well be significantly altered by climate change. Over the last few years, global temperature has increased rapidly and continuously at around 0.2°C per decade. Rise in atmospheric temperature due to climate change will lead to loss of glaciers in the Himalayas, changes in the ice caps due to melting, thinning, shrinking, retreating, freezing and disappearing. The Greater Himalayas holds the largest mass of ice outside Polar Regions and are the source of the ten largest rivers in Asia. The high Himalayan and Inner Asian ranges have 116,180 km2 of glacial ice, the largest area outside Polar Regions. Various studies suggest that warming in the Himalayas has been much greater than the global average of 0.74°C over the last 100 years. During the twentieth century, majority of the Himalayan glaciers have shown recession in their frontal parts, besides thinning of the ice mass. The melting of ice is changing the hydrological cycle and is also affecting the ocean currents. Recent measurements suggest that the mass budget over large parts of the Himalaya has been negative over the past five decades, which the rate of loss increased after roughly 1995. Monsoon-affected glaciers are more affected by climate change than winter-accumulation type glaciers. As a result of climate change, snowmelt begins earlier and winter is shorter; this affects river regimes, natural hazards, water supplies, and people’s livelihoods and infrastructure. Retreat in glaciers can destabilize surrounding slopes and may give rise to catastrophic landslides, which can sometimes lead to outbreak floods. Excessive meltwaters, often in combination with liquid precipitation, may trigger flash floods or debris flows. Initially, increased melting will result in increased discharge. With time, however, as glaciers completely disappear or approach new equilibrium, long-term effects will be increasing water shortages and limited supplies for downstream communities, particularly during the dry season. The cascading effects of rising temperatures and loss of ice and snow in the Himalayan region are affecting water availability (amounts, seasonality), biodiversity (endemic species, predator–prey relations), ecosystem boundary shifts (tree-line movements, high-elevation ecosystem changes), and global feedbacks (monsoonal shifts, loss of soil carbon).S have so far assembled substantial amount of evidences that can show the extent of change of the earth’s climate and the role of human activities behind it. Climate change is expected to have considerable impacts on natural resource systems, of which the water resources are in the prime list. It has been proved that global warming and decline in rainfall may reduce net recharge and can affect groundwater levels. Intense rain for few days will result increased frequency of floods and the monsoon rain would also be lost as direct run-off, thus can decrease the groundwater recharging potential. The countries like India, where the irrigation system is mostly dependent on groundwater (in India, 52% irrigation is groundwater dependent) can suffer severely because of these changes. Production of rice, maize and wheat in the past few decades has declined in many parts of Asia due to water shortage. The most irrigated areas in India would require more water around 2025 and global net irrigation requirement would increase relative to the situation without climate change about 3.5-5% by 2025. Climate change will affect the Indian River basins significantly. River basins of Mahi, Pennar, Sabarmati and Tapi shall face water shortage conditions, while Godavari, Brahmani and Mahanadi shall not face water shortages, but severity of flood shall increase in these areas. Additionally, rise in atmospheric temperature due to climate change will also lead to loss of glaciers in the Himalayas, which, in turn, may reduce water availability in the rivers of Indus – Ganga plains. As the Indian and South Asian irrigation systems are also dependent on canals, reservoirs and rivers, glacial retreat and changed pattern of water flow in the rivers can also threatened the water availability and irrigation potential. The melting of ice is changing the hydrological cycle, and the sea level is rising gradually. Many of India’s coastal aquifers are already experiencing salinity ingress because of sea level rise. Salt water intrusion can deteriorate surface and groundwater quality, agricultural productivity and salinization of irrigation water. Linking the concept of sustainable development to climate change can provide a deep insight into the proper methods of long term societal responses to global environmental change and can help to implement the methods like rainwater harvesting, watershed development and groundwater management systems.

Induction motor fault diagnosis using labview

Now-a-days, manufacturing companies of electrical machines are in need of easy and early fault detection techniques as they are attire by the customers. Though many researchers have developed many fault diagnosing techniques, user friendly software with automated long measurement process is needed so that the non-technical persons also can operate to identify the faults occurred. In our work the healthy induction motor is modeled in stationary reference frame. Faulty conditions are included in the model to analyze the effect of fault in the motor using the user friendly software, LabVIEW.

Application of Wind Energy Source to Large Scale Desalination System Prefeasibility Analysis-Investigation of Wind Power Potential in Coastal Areas of Tamilnadu

The total power demand in our country is increasing every year because of the increasing population. Conventional energy sources are limited by the constraints such as emission of CO2, increasing price of oil etc. To increase the power generation we need to go for non conventional energy sources among which wind energy is available in abundance. This paper discusses the possibility of using wind energy for the stand alone large scale applications eliminating the constraints on the grid connection. This is the pre feasibility study of wind power generation by analyzing the daily wind patterns in the coastal areas. This forms a good base for analyzing the feasibility of standalone wind system to large scale applications. HOMER software is used as an optimization tool. From the results Chennai has better energy density and Tutukurin has higher capacity factor. The study makes it feasible to next step in analyzing the feasibility of implementing a standalone desalination unit in coastal regions of Tamilnadu.