Reza Barati-Boldaji

Physical studies of the last decade indicate that multi-junction solar cell has higher energy conversion efficiency than single-junction cells. However, choosing the type of material, modeling and finding the parameters of this type of cell has always been one of the leading challenges in this topic. Most of the proposed models are assumed to have predetermined electrical parameters of the cell or regardless of the effect of the tunnel junction, which reduces of the system. This paper discusses the modeling of solar cell triplejunction InGap/GaAs /Ge, taking into account the effect of a tunnel junction and finds the parameters of each subcellular deal. Also, predictive control will be used to control the active and reactive power of the single-phase inverter. The use of this method eliminates the need for the modulation module and the phase-lock loop (PLL). And simplifies the control algorithm for its digital implementation. The proposed cost function of this paper will be such that in addition to controlling the power of the inverter, the closed loop stability will be guaranteed based on the Lyapunov theory. Finally, the performance of the system using the software MATLAB/SIMULINK simulation will be evaluated.

This paper involves the design of non-overshooting PD and PID controllers for some special plants. The PID controller parameters are determined to reach a stable closed-loop system with monotonically decreasing frequency response. Thus specific regions in the controller parameters space are obtained. Gain crossover frequency and phase isodamping property are employed to choose an appropriate solution among the obtained solutions. The performance of the proposed PD and PID controllers in position and velocity control of a laboratory DC servomechanism system is investigated through experimental tests.