PSAM 16 - Paper Overview

PSAM 16 Conference Paper Overview

Welcome to the PSAM 16 Conference paper and speaker overview page.

Lead Author: Kim Hintz Co-author(s): Dr.-Ing. Martin Dazer, martin.dazer@ima.uni-stuttgart.de Prof. Dr.-Ing. Bernd Bertsche, bernd.bertsche@ima.uni-stuttgart.de

Availability Analysis of Photovoltaic System Concepts to Derive Reliability Requirements for Inverters within Different Application Scenarios
The energy concept based on fossil fuels is unsustainable in long term due to the ongoing shortage of resources and the associated negative impact on climate change. The remedy is offered by the sustainable, nearly inexhaustible, and almost emission-free sources of renewable energy. Photovoltaics (PV) play a key role, converting the world's solar radiation into electrical energy without emissions and thus making solar energy usable in a decentralized manner. To promote the expansion of PV systems in urban environments, manufacturers must guarantee ecological, safe, but above all economical operation for the customer. Various concepts are used for grid-connected PV systems, which differ in their electronic design and circuit layout. These include concepts based on string or module inverters as well as concepts using power optimizers. The concepts offer several advantages and disadvantages, such as the control of individual PV modules at the optimal operating point, their monitoring, as well as the flexibility in the installation. Furthermore, the profitability of the PV system depends on the specific application scenario. Here, various factors such as the system size, the orientation and angle of irradiation, partial shading as well as individual defects influence the performance of the PV system. These complex interactions make it difficult to compare the different PV system concepts. From the customer's point of view, it is difficult to select an optimal system concept due to his individual application scenario. For him, only the total costs, i.e. the sum of investment and repair costs as well as the energy yield or the feed-in compensation, are decisive for the selection of a suitable concept. The repair costs and the yield of the PV system are directly related to its availability and therefore also the reliability since a defect system cannot feed any electricity into the grid. To achieve reliability and profitability of the PV system, they must be designed for a service life of more than 20 years. In this context, the reliability requirements of the individual components vary greatly due to the different interactions within the PV system concepts and the application scenarios. Depending on the layout of the concepts, the failure of an individual component has a different effect on the overall PV system. The failure either leads to the loss of the power of individual PV modules or to the total failure of the whole PV system. This paper deals with the reliability and availability analysis of different PV system concepts in order to make predictions about their economic efficiency. On this basis, reliability requirements for individual components of the PV system can be derived, with which the economic operation of a PV system can be achieved under the consideration of different operating conditions. The evaluation is carried out using Petri nets, with which a realistic analysis of the reliability and availability of the various PV system concepts can be performed, considering the different repair times and maintenance models. In this way, the availability of the PV system and thus its delivered yield, as well as the installation and repair costs for different setups can be modeled and evaluated within a Monte Carlo simulation. Within the framework of a parameter study, the different failure behavior of individual components as well as the effects of different shading situations on the output of the PV systems are modeled. By specifying a certain application scenario and a desired break-even point, the reliability requirements for individual components of the PV systems can be derived. In this way, it is possible to determine which reliability requirements are necessary for the individual PV system concepts to ensure economic operation for the customer. Important influencing variables and realistic application scenarios such as system size and partial shading situations must be taken into account in this analysis.

Availability Analysis of Photovoltaic System Concepts to Derive Reliability Requirements for Inverters within Different Application Scenarios

The energy concept based on fossil fuels is unsustainable in long term due to the ongoing shortage of resources and the associated negative impact on climate change. The remedy is offered by the sustainable, nearly inexhaustible, and almost emission-free sources of renewable energy. Photovoltaics (PV) play a key role, converting the world's solar radiation into electrical energy without emissions and thus making solar energy usable in a decentralized manner. To promote the expansion of PV systems in urban environments, manufacturers must guarantee ecological, safe, but above all economical operation for the customer. Various concepts are used for grid-connected PV systems, which differ in their electronic design and circuit layout. These include concepts based on string or module inverters as well as concepts using power optimizers. The concepts offer several advantages and disadvantages, such as the control of individual PV modules at the optimal operating point, their monitoring, as well as the flexibility in the installation. Furthermore, the profitability of the PV system depends on the specific application scenario. Here, various factors such as the system size, the orientation and angle of irradiation, partial shading as well as individual defects influence the performance of the PV system. These complex interactions make it difficult to compare the different PV system concepts. From the customer's point of view, it is difficult to select an optimal system concept due to his individual application scenario. For him, only the total costs, i.e. the sum of investment and repair costs as well as the energy yield or the feed-in compensation, are decisive for the selection of a suitable concept. The repair costs and the yield of the PV system are directly related to its availability and therefore also the reliability since a defect system cannot feed any electricity into the grid. To achieve reliability and profitability of the PV system, they must be designed for a service life of more than 20 years. In this context, the reliability requirements of the individual components vary greatly due to the different interactions within the PV system concepts and the application scenarios. Depending on the layout of the concepts, the failure of an individual component has a different effect on the overall PV system. The failure either leads to the loss of the power of individual PV modules or to the total failure of the whole PV system. This paper deals with the reliability and availability analysis of different PV system concepts in order to make predictions about their economic efficiency. On this basis, reliability requirements for individual components of the PV system can be derived, with which the economic operation of a PV system can be achieved under the consideration of different operating conditions. The evaluation is carried out using Petri nets, with which a realistic analysis of the reliability and availability of the various PV system concepts can be performed, considering the different repair times and maintenance models. In this way, the availability of the PV system and thus its delivered yield, as well as the installation and repair costs for different setups can be modeled and evaluated within a Monte Carlo simulation. Within the framework of a parameter study, the different failure behavior of individual components as well as the effects of different shading situations on the output of the PV systems are modeled. By specifying a certain application scenario and a desired break-even point, the reliability requirements for individual components of the PV systems can be derived. In this way, it is possible to determine which reliability requirements are necessary for the individual PV system concepts to ensure economic operation for the customer. Important influencing variables and realistic application scenarios such as system size and partial shading situations must be taken into account in this analysis.

Paper KI18 Preview

Author and Presentation Info

Lead Author Name: Kim Hintz (kim.hintz@ima.uni-stuttgart.de)

Bio: Kim Hintz studied Mechanical Engineering at the University of Stuttgart in Germany and received his academic degree Master of Science in 2019. He is working as a research assistant in the field of reliability engineering at the Institute of Machine Components. He is pursuing his Ph.D. studies with a focus on reliability assessment of electronic systems.

Country: Germany
Company: Institute of Machine Components
Job Title: Research Assistant

PSAM 16 Conference Paper Overview

Welcome to the PSAM 16 Conference paper and speaker overview page.

Paper KI18 Preview

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