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Dry-type transformers are quite popular in commercial and industrial applications. The IEEE and IEC standards on dry-type transformer loading provide a significant guideline and recommendation for transformer aging rate calculation. In this study, the fundamental information in these standards are used to develop a real-time dry-type transformer thermal model and evaluate transformer insulation performance...
In this paper is presented characterization and modeling of the self-heating effect (SHE) for multifinger MOSFET transistors. The mechanism of self heating effect has been analyzed based on simulator which supporting 2D device model. By using Verilog-A language a new model is developed for BSIM6 model which considers SHE effects as well. By using a vector network analyzer an AC conductance method...
Transformer lifetime assessments plays a vital role in reliable operation of power systems. In this paper, leveraging sensory data, an approach in estimating transformer lifetime is presented. The winding hottest-spot temperature, which is the pivotal driver that impacts transformer aging, is measured hourly via a temperature sensor, then transformer loss of life is calculated based on the IEEE Std...
This contribution derives an efficient approach to model a coupled electro-thermal design problem for transient system simulation, using an analogue simulator, like SPICE. It introduces the electrical and thermal modelling procedures and the coupling of both models. The electrical model is based on the fundamental equations of semiconductor physics. Using the respective physical parameters the model...
In this paper, the effect of wind airflow over a monocrystalline photovoltaic panel (PV) was examined in relation to general velocity and temperature contours. The analysis was obtained using the developed numerical CFD model that was validated by available experimental results. The airflow velocity ranged from 0.5 m/s up to 4.0 m/s and the gained results are specified for different longitudinal cross-sections...
This paper presents a reduced order model for three way catalyst (TWC) temperature dynamics developed using Proper Orthogonal Decomposition (POD) and Galerkin projection method. The TWC thermal dynamics are described using a set of coupled, non-linear partial differential equations (PDEs). The Galerkin projection method is applied to the PDE-model to construct a set of ordinary differential equations...
The heating and cooling is very complex process for winding in large power transformer, which involves fluid dynamic, manufacture technology and numerical heat transfer and other related disciplines. Recently, the electromagnetic-Fluid-thermal coupled method and thermal network method are widely used by domestic and foreign researchers, whereas the oil flow distribution can not be taken into account...
This paper presents an electro-thermal based junction temperature (Tj) estimation method of insulated gate bipolar transistor (IGBT) power module. Firstly, the internal structure of IGBT and its transient characteristics are researched, through which the factors affecting the power loss as well as its basic influence rule are analyze and the multivariable loss calculation model is obtained. And then...
Spray cooling is a new type of high heat flux heat transfer cooling technology. In the process, cooling medium is dispersed certain microscale droplets through the nozzles and injected to the stator core and winding. The spray characteristics will affect directly the heat transfer coefficient. So in the paper a test rig using a nozzle was constructed to explore the atomization characteristics of spray...
The development of automotive lighting systems with high illumination quality and high reliability is essential for driving safe and comfort. LEDs have many superiorities over the traditional light sources, such as high reliability, good color quality, long lifetime, energy and space saving, environment friendly and so on, when they are operated under an effective health management (such as thermal,...
In this paper, the possibility of Multi-Input Single-Output control of the heat distribution processes is investigated. Based on the validated model of the example experimental setup, the static and dynamical properties of the process are investigated and discussed in terms of control performance and efficiency. Two potential manipulating variables are considered and different control strategies are...
In this paper a hybrid chemical reactor, known also as the partially simulated reactor, is presented. Such reactor consists of a jacketed vessel and LabVIEW based real-time simulator of a chemical reaction. The reactor can be used for testing advanced control strategies. Experimenting with the hybrid reactor excludes risk of a thermal runaway because the simulated chemical reaction can be stopped...
This work develops nonlinear and linear dynamic models of a multipurpose plant: a water tank fed by two flow rates (cold and hot water), which are mixed to produce an outflow rate. Such a plant is a MIMO (Multiple Input, Multiple Output) process with two inputs: cold and hot water flow rates, and two outputs: level and temperature of the water in the tank. This plant exhibits interaction between its...
Data validation and reconciliation (DVR) plays key role in industries because it uses process information and statistical methods to estimate correct measurements from the observed data. DR is very effective when measurement is free from gross error. Data observed from chemical processes can be serially correlated. Serial correlation in data can arise when a process, takes time to adjust, is exposed...
Experimental research of heat transfer and resistance characteristic of three sizes of corrugated tube and straight tube was done. The results show that the shape of the corrugated pipe enhances disturbance of liquid, and strengthens heat exchange ability of corrugated tube. Corrugated tube heat exchange ability increases while the ratio of corrugation pitch and external diameter of corrugated tube...
District heating (DH), based on electric boilers, when integrated into electric network has potential of flexible load with direct/indirect storage to increase the dynamic stability of the grid in terms of power production and consumption with wind and solar. The two different models of electric boilers for grid integration are investigated: single mass model (with uniform temperature inside tank)...
Thermoelectric generators (TEGs) are used for the direct conversion of heat energy into electricity. Given that there is an extreme concentration of heat present on house roofs, the application of TEGs on these locations is feasible. This study involves the modeling of thermoelectric generators on house roofs through the use of simulations and an actual prototype. Simulations were done using the matrix...
This article describes a remote lab for fruit and vegetable drying, and discusses feedback from students who used the lab in their training. A major conclusion of the survey was that there is interest in the remote laboratory because it provides practical experience in the training of an automation and control engineer. It can be concluded that the remote laboratory has a positive effect on the students'...
Currently, the production and the number of installations of photovoltaic (PV) modules has been increasing rapidly. Accordingly, the number of failures has also increased. Many failures are a result of the Hot-Spot phenomenon in which defective cell becomes hot when shadow occurs on the cell. Previously, the authors performed operating analysis of the PV module with Hot-Spot so that we construct a...
Gas turbine combustion system (GTCS) works in the highly adverse environmental conditions of high temperature and high pressure. Because GTCS initial temperature is too high to be directly measured, exhaust gas temperature (EGT) is an alternative to detect performance of GTCS. However, various interferences, such as working and ambient conditions as well as compressor and combustion efficiencies and...
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