ABSTRACT
Globally, the demand for energy from renewable sources is growing due to the increasing electricity consumption and the pollution of fossil fuels. The government has framed various policies to facilitate green energy generation, encouraging renewable energy source usage through PV installations in multiple sectors, including educational institutions. The primary objective of this paper is to propose a methodological approach for analysing the performance of the installed PV system on the rooftop of a university building in Tamil Nadu, India. The site selected is favourable for electricity generation from PV systems with an average global solar radiation of 5.82 kWh/m2day. Solar energy changes periodically with annual and daily variations and is not steady due to seasonal changes. The step-by-step performance assessment and the annual performance of the 100-kW solar PV system, which was instituted in 2019, with the forecasted parameters, are presented in this paper. Therefore, the assessment analysis is carried out in four phases: feasibility assessment, Energy yield assessment, Life cycle assessment, and Power quality assessment. To improve the solar PV output and efficiency, considering the solar irradiation, temperature, wind velocity, etc., PV yield is measured to evaluate the PV system's energy metrics. This paper also considers the carbon credits earned, solar power generated in the location, and the payback period. The power quality assessment is carried out in this paper to test the PV plant's compliance with effective grid integration.
ABSTRACT
This letter presents a new single-stage common ground type nine-level (9L) switched-capacitor inverter topology with single-phase operation. The primary objective of this topology is to reduce the leakage current, voltage boosting, and maintain the voltage across the switched capacitors. The output voltage (vo) can be boosted up to two times the input voltage (vin). The various modes of operations are explained in detail, and the simulation results are provided to illustrate the effectiveness of the proposed topology. Next, the experimental results are obtained from a 500 W prototype setup and tested under different scenarios such as load variations, input voltage, and modulation index. Both simulation and experimental results have a good agreement regarding efficiency and performance. Finally, a detailed comparative study is performed with other recent 9L switched-capacitor inverters to prove the merits of the proposed topology.
ABSTRACT
The boost-switched capacitor inverter topology with reduced leakage current is highly suitable for distributed photovoltaic power generation with a transformerless structure. This paper presents a single-stage 5-level (5L) transformerless inverter with common ground (CG) topology for single-phase grid-connected photovoltaic application. A generalized version of the proposed topology is also presented. The proposed topologies are derived by combining the dc/dc boost converter and switched capacitor cell. The primary focus has been given to the 5L version of the proposed topology. The number of switch counts is reduced, the maximum voltage gain is four times, and the inrush current is suppressed due to the input inductor configuration. Also, the voltages across the switched capacitors (SCs) are self-balanced. The negative source terminal and the load are connected directly to suppress the leakage current. It is thoroughly compared with other recent CG-Type topologies to attest to the advantages of the proposed topology. The laboratory prototype is developed for 600 W with the maximum efficiency is 94.21%, and the maximum source current is not more than 25A. Further, the operation of the proposed topology is verified under dynamic loading conditions, and the results are presented.
ABSTRACT
Multilevel inverters play an important role in extracting the power from renewable energy resources and delivering the output voltage with high quality to the load. This paper proposes a new single-stage switched capacitor nine-level inverter, which comprises an improved T-type inverter, auxiliary switch, and switched cell unit. The proposed topology effectively reduces the DC-link capacitor voltage and exhibits superior performance over recently switched-capacitor inverter topologies in terms of the number of power components and blocking voltage of the switches. A level-shifted multilevel pulse width modulation scheme with a modified triangular carrier wave is implemented to produce a high-quality stepped output voltage waveform with low switching frequency. The proposed nine-level inverter's effectiveness, driven by the recommended modulation technique, is experimentally verified under varying load conditions. The power loss and efficiency for the proposed nine-level inverter are thoroughly discussed with different loads.
