Chair(s): Carlo Muscas University of Cagliari Italy Email The goals of this Committee are to: The aim of TC-39 is to gather people involved in the field of measurements in power systems in order to lead the research on specific topics, promote and facilitate the exchange of knowledge between scientists, encourage the research on challenging topics, organize events related to the measurements in power systems, become an official consultative body for industries and operators in the field of power systems, as far as the design and development of specific instrumentation is concerned, and, last but not least, promote and disclose new Standards and Guidelines. Background Electric power systems represent one of the main tasks in the field of engineering. Since the last 70 years the demand and consumption of electric energy has grown exponentially. Originally the attention paid to electric energy was mainly limited to the analysis of its characteristic in terms of waveform, interruptions and continuity of service. As the demand increased, as well as the diffusion of devices highly sensitive to voltage characteristics, the need for accurate measurements of electrical quantities has become both strategic and necessary. The economic losses for industries have dramatically increased due to the poor quality of the supply voltages. In several applications, accurate power measurements are required for taking decisions, for diagnostic purposes, for metering purposes, and for reliability analysis. The challenge, in the recent years, is represented by the development of a new generation of instruments capable of providing the required measurement information, which differs, sometimes strongly, from that required in the past. For instance the measurement of the active power and RMS values must be performed assuming that the electrical quantities are no longer periodic nor sinusoidal. Fault detection and localization in power plants is becoming a crucial task for the Utilities in order to improve the voltage quality and shorten the time-to-restoration. This challenge can be won only by adopting synchronized distributed measurement systems, and implementing a new kind of algorithms and synchronization protocols. Also diagnostic needs in power systems are growing faster and faster: measurement instruments for the reliability evaluation of cables, transformers, motors, drivers is covering an increasing portion of the power instrumentation market. Moreover new kind of approaches, theories and methods need to be studied to correctly provide the required information, such as the accurate measurement of the instantaneous power frequency and the spectral content of the electrical quantities, the implementation of the synchrophasor theory, and the development of accurate voltage and current transducers for metering purposes, partial discharge measurement, loss measurements in cables and transformers, and temperature measurements in power plants.