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Early degradation factors of solar 33 kV grid connected power plant, a comparative study
This paper identifies and analyses early degradation mechanisms observed in photovoltaic (PV) modules of power plants over 7 years of operation on the coast power grid in Mauritania. Performance degradation takes place due to several reasons such as material degradation following dust accumulation, high temperature, and humidity. Also, mismatch of electric power parameters such as increasing loads above projected values of the plant. Therefore, this paper analyses and studies the degradation in four phases. First, the visual inspection detects the degradation of materials and defects such as the presence of dust, cracks, browning (discoloration), and connection corrosion. The second phase proposes a mathematical model to calculate the early degradation rate (DR) of different components, such as short circuit current (Isc), open circuit voltage (VOC), the maximum yield power (Pmax), and the fill factor (FF) of the PV module. The third phase is a MATLAB modeling of the measured real-time data of the operating PV system to test Power versus voltage curves (with and without degradation) to examine the presence of failure of PV modules. Finally, compare the evolution of real-time production data for three measured years (2015, 2016, and 2017) with the simulation curves of this study.
Read MoreEnhancing the output power of solar cell system using artificial intelligence algorithms
The main objective of research in the field of solar cell systems is to obtain the maximum output power. In this respect, artificial intelligence (AI) is considered the current icon. Hence, in the present paper perturbation & observation (P&O) and particle swarm optimization (PSO) algorithms were used to achieve the maximum power. Solar irradiance at three different regions of Egypt was measured using a new technique based on Arduino microcontroller. The obtained experimental results of the solar irradiance were inlaid to the MATLAB simulation program to study the performance of the proposed algorithms. Many improvements were carried out in P&O and PSO algorithms to harvest maximum power for long hours daily by a continuous modulation of the duty cycle. The output maximum power and the reaching time of both improved P&O and PSO are better than the traditional one and PV array, which indicates their efficiency in harvesting the maximum power and enhancing the performance of solar cell systems. The reinforcing of the PV system by P&O improved its efficiency by 98.733%, while PSO improved its efficiency by 99.968%.
Read MoreA non-invasive technique for monitoring supply voltage variation to single phase induction motor using doppler UWB radar signal analysis
The induction motors (IMs) are important components of various industries. The condition of IMs monitored continuously using contact and non-contact methods continuously. The contact methods are expensive, complex and difficult to implement. This paper proposes a non-contact method of fault identification in the single-phase induction motor operating in different conditions by analyzing doppler ultra-wide band (UWB) radar signal. The UWB radar generates a high frequency signal, which is transmitted on to the Induction motor form transmitter and software phase locked loop (SPLL) condition received signal from the receiver. The PLL implements as low pass filter, receives reflected signal from an induction motor along with high frequency noise. The received signal filtered to remove the high frequency noise and filtered output is analyzed to identify the different faults such as over voltage faults and under voltage faults when the motor is running with high, medium and low speed. The proposed non-invasive method has advantages compared to other such as the sensor’s sensitivity will not affect with motor temperature and accuracy will not change with position of the sensor and presence of other machines.
Read MoreComparing performance and complexity of TCHB and CHB multilevel inverters using NLC technique
This paper presents a modulation strategy applied to a 13-level three-phase transistor clamped H-bridge (TCHB) inverter, aimed at a renewable and electric vehicle drives application. A comparison is performed between the TCHB inverter and a traditional cascaded H-bridge (CHB) inverter, considering circuit complexity, switching losses, and total harmonic distortion (THD) attained from each multilevel inverter topologies. The TCHB inverter achieves a 13-level output with only 15 switches, whereas the conventional CHB inverter requires 24 switches. The modulation technique, employing a nearest level control, yields improved output quality for both the TCHB and CHB multilevel inverters. The results demonstrate that this strategy effectively minimizes the overall THD. Notably, previous modulation techniques mainly focused on carrier-based PWM or SVPWM, making this approach distinctive. The FFT analysis reveals a voltage THD of 5.49% for TCHB and 5.15% for CHB, indicating a marginal difference in THD content for each multilevel inverter. Despite the CHB inverter experiencing double the switching stress compared to TCHB, since less switches are required in the TCHB inverter, consequently, the system's total cost and complexity are reduced. The achieved results are verified through the use of simulations carried out in the MATLAB Simulink.
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