Light source position microsensor

There exist industrial applications where an accurate estimation of a light source position is needed. That is the case for a heliostat, a device that projects sunlight upon a focus hundreds of meters distant. In this paper a novel sensor design to generate an alignment sensor signal is presented. A detailed study of its response is included, showing that there exist several design parameters to achieve a desired accuracy. This sensor has been implemented using bipolar technology and chip to board bonding, and experimental results obtained in the laboratory are given.Peer ReviewedPostprint (published version

Grid-Connected Photovoltaic Generation Plants: Components and Operation

The main design objectives of photovoltaic (PV) systems have been for a long time to extract the maximum power from the PV array and to inject it into the AC grid. Therefore, the maximum power point tracking of a uniformly irradiated PV array and the maximization of the conversion efficiency have been the main design issues. But also, when the PV plant is connected to the grid, special attention has to be paid to the reliability of the system, the power quality and the implementation of protection and grid synchronization functions. Modern power plants are required to maximize their energy production requiring suitable control strategies to solve the problems related to the partial shading phenomena and different orientation of the PV modules towards the Sun. Moreover, the new policy concerning the injection of reactive power into the grid makes the development of suitable topologies and control algorithms mandatory. A general view of actual solutions for applications of the PV energy systems is presented. The paper covers some important issues such as the most reliable models used for simulation that are useful in the design of control systems, and the maximum power point tracking function, especially in distributed applications. The main topologies used in the PV power processing system and, finally, grid connection aspects are discussed, especially as far as synchronization, protections and integration are concerned

Multilevel 24-Sided Polygonal Voltage-Space-Vector Structure Generation for an IM Drive Using a Single DC Source

Conventional two-level as well as multilevel voltage-source-inverter topologies with a hexagonal voltage-space vector structure generate low-order harmonics in the machine terminal voltages when operated beyond the linear modulation range in variable speed drive application. Progressing from hexagonal to a higher sided polygonal voltage-space-vector structure (VSVS) suppresses significant low-order harmonics throughout the modulation range. In addition, the linear modulation range will also be enhanced very near to the base speed. In this paper, for the first time, the generation of a multilevel 24-sided VSVS using a single dc source for induction-motor drives is proposed. A cascaded topology with a dc-source-fed flying-capacitor inverter and two low-voltage capacitor-fed H-bridge cells forms the power circuit. The features and advantages of the proposed scheme are validated through experimental results and discussions

Light source position microsensor

There exist industrial applications where an accurate estimation of a light source position is needed. That is the case for a heliostat, a device that projects sunlight upon a focus hundreds of meters distant. In this paper a novel sensor design to generate an alignment sensor signal is presented. A detailed study of its response is included, showing that there exist several design parameters to achieve a desired accuracy. This sensor has been implemented using bipolar technology and chip to board bonding, and experimental results obtained in the laboratory are given.Peer Reviewe