Power quality monitoring in sustainable energy systems

Modern world is under tremendous pressure for alternative sources of energy and the trends are towards sustainable energy. Present power systems are facing heavy economic losses for poor power qualities. Efficiency of sustainable energy depends on the power quality of the supply. Presently, Power Quality issues are major problems for utilities, customers and end users. The cost of poor PQ is high and gradually rising. The paper gives insights on global economical losses due to poor PQ. The business risk posed by PQ problems is a real one with even low tech industries exposed to serious financial losses. It has been observed that the consequences of poor PQ would have large financial impacts on a country´s economy, and more initiatives are required from the concerned parties and regulating bodies to take corrective measures for maintaining better power quality. Especially for successful sustainable energy programme, Power Quality Monitoring can help identify the cause of power system disturbances and the problem conditions on a system before they cause interruptions or disturbances. In an environment of sustainable energy and modern grid, intelligent PQ monitoring is essentially required to solve different PQ related problems. Authors proposed an intelligent power quality monitoring system using virtual instrumentation and appropriate data acquisition system to detect different PQ disturbances. The system is user friendly due to its graphical user interface. The tests were done in the Energy Laboratory of NIT, Silchar (India) and Research Lab, Electrical Engineering Department, AMU, Aligarh (India). The available energy in both the labs was solar energy. The qualities monitored include voltage fluctuations, sag, swell, interruptions, harmonics etc. The huge amount of acquired data has been analyzed using quadratic discriminant analysis technique to determine the condition of the waveforms. The system shows fast response with accuracy in monitoring desired power qua- ities.