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The method of evaluating color rendering using a visual, graphical metric is presented. A two-dimensional Color Rendering Map (CRM) of a light source's color-rendering capabilities is explained and demonstrated. Extension of this technique to three-dimensional CRMs of objects under illumination is explained, including the method of introducing numerical indices in order to evaluate standards for specific applications in lighting. Three diverse applications, having a range from subtle to significant color variation, are shown with their respective CRMs. These three applications are also used to demonstrate how three differing light sources produce different maps. The results show a flexible, simple method to obtain a clear, visual determination of color rendering performance from differing sources used in differing illumination applications. The use of numeric indices in these applications shows how specific standards can be imposed in assessing the applicability of a light source.

This paper provides a review of the literature addressing sensorless operation methods of PM brushless machines. The methods explained are state-of-the-art of open and closed loop control strategies. The closed loop review includes those methods based on voltage and current measurements, those methods based on back emfmeasurements, and those methods based on novel techniques not included in the previous categories. The paper concludes with a comparison table including all main features for all control strategies.

Economic, social and environmental concerns demand higher efficiency and more sustainable electrical power systems. Then, power systems need to evolve from its traditional conception to future power systems. New nonconventional generators are distributed in power systems, most of them based on renewable resources, which have been developed and connected to the grid. Wind power is nowadays considered as one of this future renewable energy sources and it is more and more spread over the world. But there are a number of technical issues to be solved in order to accommodate these new units. Moreover, technical grid code requirements and regulations vary considerably from country to country. Denmark is the leader in wind power integration and development, and it is considered as a pattern to be followed. Wind power in Spain is also important. However, there are some facts between both countries that cause important differences. This paper points out some of them and suggests some strategies to be dealt with regarding wind power integration in Spain.