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Varying solar radiation on photovoltaic (PV) panels reduces the PV system's output and increases the mismatch losses. Several techniques have been proposed to solve the mismatch problem, for example, the reconfiguration technique of PV panels.Most of the reconfiguration techniques have been proposed for small systems because of the difficulty in applying to large systems as a large number of switches are required for such applications. In this paper, a new technique based on total-cross-tied (TCT) in two reconfigurable stages is proposed. In the first stage, the shading over the PV plant is dispersed by switching between arrays. In the second stage, the shade dispersion from the first stage is increased by optimizing between the columns. The number of switches and sensors were reduced by using genetic algorithm, thus reducing the system cost. To demonstrate the proposed new reconfiguration technique, four shaded cases were simulated and tested using MATLAB/SIMULINK. A comprehensive analysis of power-voltage (P-V) curves and row currents calculation was performed, for TCT configuration and the proposed new reconfiguration technique. Also, a comparative study on performance analysis, energy-saving, and income generation was carried out for each shading case. The comparative study of the four cases shows that the reconfiguration techniques proposed in two stages generate more power under partial shading conditions than TCT. Further research is needed to ensure the practicality of the switches needed to realize this technique.

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Given the volatile market prices and impending reduction in fuel supplies, electric vehicles (EV) have drawn increasing attention. The electric motor in EVs is an important component because it functions as an engine during acceleration and as a generator during deceleration or braking. Energy is saved in these processes when the kinetic energy is converted into electrical energy, which is then stored in a storage system by a regenerative braking system (RBS). In terms of highly efficient performance, ideal torque and speed, high-powered density, and cost-effective maintenance, brushless DC (BLDC) motors are preferred. This paper aims to explore and propose a seamless and effective method of RBS for a BLDC motor in an EV. In braking mode, the proposed method change the motor to act as a generator even without any additional converter, ultra-capacitor, or a complex winding-changeover technique. In this mechanism, the energy flows to the DC side. By using MATLAB/SIMULINK, the BLDC motor with speed and current controller is simulated. Accordingly, in the deceleration or braking mode, the motor functions as a generator and transports the power to the DC side. The proposed model is validated in both starting or no-load and load conditions.