Solar photovoltaic fed dual input LED lighting system with constant illumination control

A dual input LED lighting scheme with constant illumination is proposed in this paper. The scheme employs a photovoltaic array as the first input and a battery as the second one. A microcontroller is programmed to operate a changeover switch as well as a DC-DC converter for uninterrupted and constant illumination in work place. The scheme is suitable for conference halls, laboratories, clean rooms, marriage halls, theaters, etc. The complete modeling, design and experimentation of the proposed scheme are explained and the economic viability of the scheme is justified.     

Performance Enhancement of Power System Stabilizer Through Colony of Foraging Ants

In this article, the concept of foraging behavior of a colony of natural ants is used for the optimal design of power system stabilizers. The controller design is formulated as an optimization task and the novel concept is used to derive the controller structure. The proposed approach is applied to the multi-machine test systems. The dynamic performance of the system has been examined under different perturbations and loading conditions. Various performance characteristics of the technique are thoroughly investigated and compared with the genetic algorithm based approach. The comparison shows that the ant colony optimization based technique converges much faster with lesser number of iterations through simple computational steps. It is also shown through extensive simulations that the proposed controller gives an excellent damping performance over different disturbances and wide range of operating conditions.