This paper presents the electrical and mathematical model of the supercapacitor. The equivalent mathematical model derived from electrical model was used to simulate the voltage response of the supercapacitor. The model has been implemented using Matlab software program. Simulation and experimental results of the voltage charging/discharging of the supercapacitor are compared. It was found out that the results obtained using the model is in good agreement with the experimental one. Moreover a mathematical model for the efficiency as a function of discharge time was developed and presented. The effect of charge/discharge rate on the supercapacitor's temperature is also experimentally considered. Experiments show that during charging the temperature rises more than during discharging.

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In this paper, the dynamic mathematical model of a proton exchange membrane (PEM) fuel cell is presented. Dynamic performance of a PEM fuel cell system by experimental and simulation using matlab/simulink is investigated. The V-I load characteristics of a 1.2 kW PEM fuel cell are presented. Result shows that the starting current of the PEM fuel cell operated at rated load reaches to approximately twice of its rated current in just less than 0.015 second before it reached to its steady state condition. Step change load responses of this PEM fuel cell were experimented and simulated. It was found out, from the results obtained, that PEM fuel cell had a very fast response to load changes. Moreover, results show that the experimental and the result computed by using the simulation of the model are very close to each other which validates the model. Hence, this model could be used to implement a controller design in order to come up with an optimal and efficient operation of PEM fuel cell. Based also on the results, a suitable power conditioning can be constructed and designed for safe and reliable operation of PEM fuel cell especially in integrating and connecting it to a hybrid wind/PV distributed generation system.

The stream and rain data acquisition system presented in this paper makes the mapping of hydro potentials in the region or of the country economically and practically possible. Moreover, it can also serve as a flood warning system.