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Article
Publication date: 20 May 2020

Sathish Kumar, Oleg R. Kuzichkin, Ahmed Faisal Siddiqi, Inna Pustokhina and Aleksandr Yu Krasnopevtsev

This study aims to investigate simultaneous power and thermal loading.

138

Abstract

Purpose

This study aims to investigate simultaneous power and thermal loading.

Design/methodology/approach

Finite element method simulations coupled with experiments.

Findings

The effects of power cycling have been determined.

Originality/value

This paper aims to testify the combined effects of thermal and power cycling loads on the reliability of solder ball joints with barrel- and hourglass-type geometries in an electronic system. The finite element simulation outcomes showed that the maximum strain energy was accumulated at the edges of barrel-type solder, whereas the hourglass-type was vulnerable at the necking side. It was also found that the hourglass-type solder showed a reliable behavior when the sole thermal cycling was exerted to the electronic system, whereas the barrel-type solder was a better choice under simultaneous application of thermal and power loadings. The experimental results also confirmed the finite element simulation and indicated that the solder joint reliability strongly depends on the geometry of interconnection in different operating conditions. An extensive discussion was presented to shed light on the paramount importance of combined thermal/power cycling on the reliability of solder joints.

Details

Soldering & Surface Mount Technology, vol. 33 no. 1
Type: Research Article
ISSN: 0954-0911

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Article
Publication date: 4 August 2014

Krzysztof Górecki

The purpose of this paper is to present a new method of measuring thermal resistance of power light-emitting diodes (LEDs). Properties of power LEDs strongly depend on their…

164

Abstract

Purpose

The purpose of this paper is to present a new method of measuring thermal resistance of power light-emitting diodes (LEDs). Properties of power LEDs strongly depend on their internal temperature. The value of this temperature depends on the cooling conditions characterized by thermal resistance.

Design/methodology/approach

The new method of measuring the value of this parameter belongs to the group of electric methods. In this method, the problem of estimating the value of electrical power converted into light is solved. By comparing the values of the case temperature obtained for the LED operating in the forward mode and the reverse-breakdown mode, the thermal power is estimated. On the basis of the measured value of the thermally sensitive parameter (the LED forward voltage) and the estimated value of the thermal power, thermal resistance is calculated.

Findings

The elaborated method was used to measure thermal resistance of the selected types of power LEDs operating at different cooling conditions. The correctness of the elaborated measurement method was proved by comparing the results of measurements obtained with the use of the new method and the infrared method.

Research limitations/implications

On the basis of the obtained results of measurements and the catalog data of the tested diodes, the dependence of the measurement error of thermal resistance of the LED on its luminous efficiency is discussed.

Originality/value

The new measurement method is easy to use and more accurate than the classical method of thermal resistance measurement of the diode.

Details

Microelectronics International, vol. 31 no. 3
Type: Research Article
ISSN: 1356-5362

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Article
Publication date: 26 February 2025

ShengYi Du, DongHong Tan and Zitong Chen

This study aims to propose a comprehensive optimization and scheduling method for the combined heat and power (CHP) systems that takes into account the uncertainties of wind power

8

Abstract

Purpose

This study aims to propose a comprehensive optimization and scheduling method for the combined heat and power (CHP) systems that takes into account the uncertainties of wind power and demand response.

Design/methodology/approach

The uncertainty of wind power and the “thermal-electric coupling” characteristics of CHP units have led to an increasing issue of wind power curtailment in CHP systems. With the objective of minimizing the overall scheduling cost of the CHP system, this paper considers the characteristics of interactive loads and wind power uncertainty, and establishes a coordinated optimization scheduling model for the generation-load-storage of the system, based on the inclusion of thermal energy storage devices.

Findings

During the optimization scheduling process, the proposed method in this paper reduces the scheduling cost by ¥99,900 (approximately 36.3%) compared to traditional methods, and significantly decreases the wind power curtailment rate by 53.7%. These results clearly demonstrate the significant advantages of the proposed method in enhancing the economic efficiency of the system and improving wind power integration.

Research limitations/implications

However, the planning process did not take into account the impact of unit combinations and grid structures.

Practical implications

This study proposes a comprehensive optimization and scheduling method for the CHP systems that takes into account the uncertainties of wind power and demand response. The objective function is to minimize the wind curtailment rate’s total scheduling cost, considering the impact of wind power uncertainties and demand response. A coordinated optimization and scheduling model for the generation-load-storage of CHP system is established.

Social implications

CHP units achieve the coupling of electric and thermal energy, significantly improving energy efficiency. In this study, the planning of the CHP system considers the coupling relationships among multiple energy sources, various devices and the pricing optimization spaces of electric and thermal forms of generation, storage and load-side. This approach has achieved favorable results in terms of economic operation scheduling and wind power accommodation improvement.

Originality/value

The case method is used to handle the uncertainty of wind power output on the generation side. Demand response is integrated on the load side to adjust user load curves. On the storage side, the thermal-electric coupling constraints of the CHP units are decoupled using thermal energy storage devices, while considering the economic benefits of all three parties involved: the power source, the load and the energy storage.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 44 no. 2
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 16 April 2018

Yao-yao Song, Hui-hui Liu, Xiao-xiao Liu and Guo-liang Yang

This paper aims to measure Chinese regional thermal industries’ evolution.

183

Abstract

Purpose

This paper aims to measure Chinese regional thermal industries’ evolution.

Design/methodology/approach

This paper uses data envelopment analysis (DEA) and global Malmquist–Luenberger productivity (GMLP) index.

Findings

The results reveal that the development of Chinese thermal power industry varies significantly in different regions, and it is highly correlated with the level of local economic development. Although the change of technical efficiency and scale efficiency had different impacts on different regions from year to year, the overall GMLP index change shows a close relationship with the contemporaneous frontier shift.

Practical implications

The results indicate that the Chinese Government should make efforts to promote its policy implementations and regulations in thermal industries so that the contemporaneous frontier will shift toward the global technology frontier with more desirable outputs and less undesirable outputs.

Originality/value

As an application, this study uses DEA and GMLP index to measure the productivity of Chinese thermal industries in 30 Chinese provinces from 2006 to 2013. The results have the meaningful policy implications for decision makers in charge of Chinese thermal industries.

Details

International Journal of Energy Sector Management, vol. 12 no. 2
Type: Research Article
ISSN: 1750-6220

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Article
Publication date: 5 September 2016

Åsa Grytli Tveten, Jon Gustav Kirkerud and Torjus Folsland Bolkesjø

This study aims to investigate the effects of thermal–hydro interconnection on the revenues, market value and curtailment of variable renewable energy (VRE). The increasing market…

302

Abstract

Purpose

This study aims to investigate the effects of thermal–hydro interconnection on the revenues, market value and curtailment of variable renewable energy (VRE). The increasing market shares of VRE sources in the Northern European power system cause declining revenues for VRE producers, because of the merit-order effect. A sparsely studied flexibility measure for mitigating the drop in the VRE market value is increased interconnection between thermal- and hydropower-dominated regions.

Design/methodology/approach

A comprehensive partial equilibrium model with a high spatial and temporal resolution is applied for the analysis.

Findings

Model simulation results for 2030 show that thermal–hydro interconnection will cause exchange patterns that to a larger extent follow VRE production patterns, causing significantly reduced VRE curtailment. Wind value factors are found to decrease in the hydropower-dominated regions and increase in thermal power-dominated regions. Because of increased average electricity prices in most regions, the revenues are, however, found to increase for all VRE technologies. By only assuming the planned increases in transmission capacity, total VRE revenues are found to increase by 3.3 per cent and VRE electricity generation increases by 3.7 TWh.

Originality/value

The current study is, to the authors' knowledge, the first to analyze the effect of interconnection between thermal- and hydropower-dominated regions on the VRE market value, and the authors conclude that this is a promising flexibility measure for mitigating the value-drop of VRE caused by the merit-order effect. The study results demonstrate the importance of taking the whole power system into consideration when planning future transmission capacity expansions.

Details

International Journal of Energy Sector Management, vol. 10 no. 3
Type: Research Article
ISSN: 1750-6220

Keywords

Available. Open Access. Open Access
Article
Publication date: 9 November 2022

Guoquan Xu, Shiwei Feng, Shucen Guo and Xiaolan Ye

China has proposed two-stage goals of carbon peaking by 2030 and carbon neutralization by 2060. The carbon emission reduction effect of the power industry, especially the thermal

970

Abstract

Purpose

China has proposed two-stage goals of carbon peaking by 2030 and carbon neutralization by 2060. The carbon emission reduction effect of the power industry, especially the thermal power industry, will directly affect the progress of the goal. This paper aims to reveal the spatial-temporal characteristics and influencing factors of carbon emission efficiency of the thermal power industry and proposes policy suggestions for realizing China’s carbon peak and carbon neutralization goals.

Design/methodology/approach

This paper evaluates and compares the carbon emission efficiency of the thermal power industry in 29 provinces and regions in China from 2014 to 2019 based on the three-stage slacks-based measure (SBM) of efficiency in data envelopment analysis (DEA) model of undesired output, excluding the influence of environmental factors and random errors.

Findings

Empirical results show that during the sample period, the carbon emission efficiency of China’s thermal power industry shows a fluctuating upward trend, and the carbon emission efficiency varies greatly among the provincial regions. The carbon emission efficiency of the interregional thermal power industry presents a pattern of “eastern > central > western,” which is consistent with the level of regional economic development. Environmental factors such as economic level and environmental regulation level are conducive to the improvement of carbon emission efficiency of the thermal power industry, but the proportion of thermal power generation and industrial structure is the opposite.

Originality/value

This paper adopts the three-stage SBM–DEA model of undesired output and takes CO2 as the undesired output to reveal the spatial-temporal characteristics and influencing factors of carbon emission efficiency in China’s thermal power industry. The results provide a more comprehensive perspective for regional comparative evaluation and influencing factors of carbon emission efficiency in China’s thermal power industry.

Details

International Journal of Climate Change Strategies and Management, vol. 15 no. 2
Type: Research Article
ISSN: 1756-8692

Keywords

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Article
Publication date: 6 March 2019

Achala Jain and Anupama P. Huddar

The purpose of this paper is to solve economic emission dispatch problem in connection of wind with hydro-thermal units.

137

Abstract

Purpose

The purpose of this paper is to solve economic emission dispatch problem in connection of wind with hydro-thermal units.

Design/methodology/approach

The proposed hybrid methodology is the joined execution of both the modified salp swarm optimization algorithm (MSSA) with artificial intelligence technique aided with particle swarm optimization (PSO) technique.

Findings

The proposed approach is introduced to figure out the optimal power generated power from the thermal, wind farms and hydro units by minimizing the emission level and cost of generation simultaneously. The best compromise solution of the generation power outputs and related gas emission are subject to the equality and inequality constraints of the system. Here, MSSA is used to generate the optimal combination of thermal generator with the objective of minimum fuel and emission objective function. The proposed method also considers wind speed probability factor via PSO-artificial neural network (ANN) technique and hydro power generation at peak load demand condition to ensure economic utilization.

Originality/value

To validate the advantage of the proposed approach, six- and ten-units thermal systems are studied with fuel and emission cost. For minimizing the fuel and emission cost of the thermal system with the predicted wind speed factor, the proposed approach is used. The proposed approach is actualized in MATLAB/Simulink, and the results are examined with considering generation units and compared with various solution techniques. The comparison reveals the closeness of the proposed approach and proclaims its capability for handling multi-objective optimization problems of power systems.

Details

International Journal of Energy Sector Management, vol. 13 no. 4
Type: Research Article
ISSN: 1750-6220

Keywords

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Article
Publication date: 16 July 2024

Mahmoud Afshari, Mehrdad Khandaei, Reza Shoja Razavi and Seyed Masoud Barekat

The net power delivered to the surface of parts (i.e. the actual heat flux) is a key parameter in the laser melting process and its exact control has a great impact on the…

45

Abstract

Purpose

The net power delivered to the surface of parts (i.e. the actual heat flux) is a key parameter in the laser melting process and its exact control has a great impact on the numerical solutions. In this paper, the impact of laser additive manufacturing parameters including laser power, scanning speed and powder injection rate on thermal efficiency, net power delivered to the part and power loss due to powder flow has been investigated.

Design/methodology/approach

The response surface method was applied to measure the net laser power in laser deposited Inconel 718 using k-type thermocouples. The temperature history obtained by thermocouples was used to calculate the net power delivered by inverse analysis method. The applied model is Rosenthal's optimized model, in which all the thermal properties of the material are considered to vary with temperature.

Findings

The results indicated that the thermal efficiency, power delivered to the part and power loss can be optimized simultaneously at laser power of 400 W, scanning speed of 2 mm/s and powder injection rate of 200 mg/s. The microstructure analysis indicated that a high-quality sample without microstructural defects was formed under optimal condition of parameters. Moreover, the primary dendrite arm spacing for the optimal sample was higher than that obtained for other samples.

Originality/value

The novelty of this research summarized as follows: Prediction of the thermal efficiency and power loss during the laser metal deposition of Inconel 718 superalloy using the inverse analysis. Finding the optimal values of thermal efficiency, power delivered to the surface and power loss in the laser metal deposition of Inconel 718 superalloy. Investigating the effect of laser power, powder injection rate and scanning speed on the thermal efficiency and power loss of Inconel 718 superalloy during the laser metal deposition.

Details

Rapid Prototyping Journal, vol. 30 no. 7
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 3 August 2010

Moez Ayadi, Mohamed Amine Fakhfakh, Moez Ghariani and Rafik Neji

Power modules including the insulated gate bipolar transistor (IGBT) are widely used in the applications of motor drivers. The thermal behavior of these modules makes it important…

330

Abstract

Purpose

Power modules including the insulated gate bipolar transistor (IGBT) are widely used in the applications of motor drivers. The thermal behavior of these modules makes it important to choose the optimum design of cooling system. The purpose of this paper is to propose an RC thermal model of the dynamic electro‐thermal behavior of IGBT pulse width modulation inverter modules.

Design/methodology/approach

The electrothermal model has been implemented and simulated with a MATLAB simulator and takes into account the thermal influence between the different module chips based on the technique of superposition.

Findings

This study has led to a correction of the junction temperature values estimated from the transient thermal impedance of each component operating alone.

Originality/value

In this paper, an experimental technique of a thermal influence evaluation is presented.

Details

Microelectronics International, vol. 27 no. 3
Type: Research Article
ISSN: 1356-5362

Keywords

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Article
Publication date: 7 August 2020

Przemysław Ptak, Krzysztof Górecki, Agata Skwarek, Krzysztof Witek and Jacek Tarasiuk

This paper aims to present the results of investigations that show the influence of soldering process parameters on the optical and thermal parameters of power LEDs.

121

Abstract

Purpose

This paper aims to present the results of investigations that show the influence of soldering process parameters on the optical and thermal parameters of power LEDs.

Design/methodology/approach

The power LEDs were soldered onto metal core printed circuit board (MCPCB) substrates in different soldering ovens: batch and tunnel types, characterized by different thermal profiles. Three types of solder pastes based on Sn99Ag0.3Cu0.7 with the addition of TiO2 were used. The thermal and optical parameters of the diodes were measured using classical indirect electrical methods. The results of measurements obtained were compared and discussed.

Findings

It was shown that the type of oven and soldering thermal profile considerably influence the effectiveness of the removal of heat generated in the LEDs tested. This influence is characterized by thermal resistance changes. The differences between the values of this parameter can exceed 20%. This value also depends on the composition of the soldering paste. The differences between the diodes tested can exceed 15%. It was also shown that the luminous flux emitted by the diode depends on the soldering process used.

Practical implications

The results obtained could be useful for process design engineers for assembling power LEDs for MCPCBs and for designers of solid-state light sources.

Originality/value

This paper presents the results of investigations into the influence of the soldering profiles and soldering pastes used on the effectiveness of the removal of heat generated in power LEDs. It shows and discusses how the factors mentioned above influence the thermal resistance of the LEDs and optical parameters that characterize the light emitted.

Details

Soldering & Surface Mount Technology, vol. 32 no. 4
Type: Research Article
ISSN: 0954-0911

Keywords

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