Xian Ma¹, Tingyan Lv^2,*, Yingqiang Jin², Rongmin Chen², Dengxian Dong², Yingtao Jia²

Energy Engineering, Vol.118, No.3, pp. 691-705, 2021, DOI:10.32604/EE.2021.012701

Abstract The large number of gas turbines in large power companies is difficult to manage. A large amount of the data from the generating units is not mined and utilized for fault analysis. This study focuses on F-class (9F.05) gas turbine generators and uses unsupervised learning and cloud computing technologies to analyse the faults for the gas turbines. Remote monitoring of the operational status are conducted. The study proposes a cloud computing service architecture for large gas turbine objects, which uses unsupervised learning models to monitor the operational state of the gas turbine. Faults such as chamber seal failure, load abnormality… More >

G. Indira Kishore¹, M. Premkumar^1,*, Ramesh Kumar Tripathi², Chandra Sekhar Nalamati²

Energy Engineering, Vol.118, No.2, pp. 199-209, 2021, DOI:10.32604/EE.2021.014079

Abstract Renewable energy with sources such as photovoltaic (PV) or fuel cells can be utilized for the generation of electrical power. But these sources generate fewer voltage values and therefore require high gain converters to match with DC bus voltage in microgrids. These high gain converters can be implemented with switched capacitors to meet the required DC bus voltage. Switched capacitors operate in a series and parallel combination during switching operation and produce high static gain, limits reverse voltage that appears across the components. A novel converter is proposed that satisfies all the features such as high voltage gain, only one… More >

Bilin Xu, Mei Han^*

Energy Engineering, Vol.118, No.2, pp. 323-339, 2021, DOI:10.32604/EE.2021.013384

Abstract Based on the theory of ecological organization, this paper analyzes the operation mechanism of chemical industry park (CIP) ecosystem by means of dynamic simulation. The research shows that the CIP ecosystem is a complex ecological system whose operation mechanism includes two levels, namely individual enterprises and ecosystem. At the level of individual enterprise, there are competition, symbiosis, invasion and other interactions between enterprises in the CIP ecosystem. Through the pre-determined judgment of the competition effect coefficient and the symbiosis effect coefficient, we calculate how the enterprises influence each other, and then generate their respective operation paths, and finally realize the… More >

Fenwicks Shombe Musonye^1,*, Hiram Ndiritu², Robert Kinyua³

Energy Engineering, Vol.118, No.2, pp. 211-224, 2021, DOI:10.32604/EE.2021.013890

Abstract Pinch Analysis is an attractive solution for reduction of thermal energy costs in thermo-chemical industries. In this approach, maximum internally recoverable heat is determined and a heat exchange network is designed to meet the recovery targets. The thermal performance of a heat exchanger over its lifetime is however a concern to industries. Thermal performance of a heat exchanger is affected by many factors which include the physical properties of the shell and tube materials, and the chemical properties of the heat transfer fluid. In this study, thermal performance of shell and tube heat exchangers designed to meet heat recovery targets… More >

Yu Liu¹, Ruiting Jiao¹, Liyao Zhao¹, Kai Liu^1,2,*

Energy Engineering, Vol.118, No.2, pp. 363-378, 2021, DOI:10.32604/EE.2021.013472

Abstract The impact of greenization on the marginal utility of the intensity of carbon emissions in China and factors influencing this relationship are explored in this study. China’s level of greenization is evaluated by using an index system developed based on the comprehensive index method. The intensity of carbon emissions is determined by using the standards for the coefficients of conversion of coal equivalent and coefficients of carbon emission. The impact of greenization on the marginal utility of the intensity of carbon emissions is then evaluated by using an elastic formula and factors affecting this relationship are verified by regression analysis.… More >

Chi Zhang, Yong Shi^*, Xuwei Gui

Energy Engineering, Vol.118, No.2, pp. 341-361, 2021, DOI:10.32604/EE.2021.014229

Abstract To realize effective utilization of renewable energy sources, a novel polymorphic topology with hybrid control strategy based LLC resonant converter was analyzed and designed in this paper. By combining the merits of a full bridge LLC resonant converter, three-level half bridge LLC resonant converter, and variable frequency control mode, the converter realizes an intelligent estimation of input voltage by automatically changing its internal circuit topology. Under this control strategy, different input voltages determine different operation modes. This is achieved in full bridge LLC mode when the input voltage is low. If the input voltage rises to a certain level, it… More >

Lian Zhang^1,2,3,*, Linjun Fan⁴, Xin Xu⁵, Baowen Cao¹, Heng Zhang², Lihong Song³

Energy Engineering, Vol.118, No.2, pp. 399-410, 2021, DOI:10.32604/EE.2021.012647

Abstract Radiator thermal performance test equipment plays a key role in the processing of developing a new type of heat radiator and its application products. The precise of temperature controlling, temperature measuring and flow measuring are the vital factors for a radiator thermal performance test equipment. Based on the above background, this paper improves the measurement and control system of radiator thermal performance test equipment, which improves the accuracy of the radiator thermal performance test equipment. This paper also optimizes the software and hardware system simultaneously so as to improve the precision of the auto-test system of test equipment. The flow… More >

Pulin Cao, Haoran Fan, Zilong Cai^*

Energy Engineering, Vol.118, No.2, pp. 265-284, 2021, DOI:10.32604/EE.2021.014513

Abstract Since the voltage source converter based high voltage direct current (VSC-HVDC) systems owns the features of nonlinearity, strong coupling and multivariable, the classical proportional integral (PI) control is hard to obtain content control effect. Hence, a new perturbation observer based fractional-order PID (PoFoPID) control strategy is designed in this paper for (VSC-HVDC) systems with offshore wind integration, which can efficiently boost the robustness and control performance of entire system. Particularly, it employs a fractional-order PID (FoPID) framework for the sake of compensating the perturbation estimate, which dramatically boost the dynamical responds of the closed-loop system, and the cooperative beetle antennae… More >

Shuowang Zhang¹, Lingxiang Huang^1,*, Dongran Song^2,*, Ke Xu¹, Xuebing Yang¹, Xiaoping Song¹

Energy Engineering, Vol.118, No.2, pp. 237-250, 2021, DOI:10.32604/EE.2021.014269

Abstract Yaw control system plays an important role in helping large-scale horizontal wind turbines capture the wind energy. To track the stochastic and fast-changing wind direction, the nacelle is rotated by the yaw control system. Therein, a difficulty consists in the variation speed of the wind direction much faster than the rotation speed of the nacelle. To deal with this difficulty, model predictive control has been recently proposed in the literature, in which the previewed wind direction is employed into the predictive model, and the estimated captured energy and yaw actuator usage are two contradictive objectives. Since the performance of the… More >

Jia Zhu^*

Energy Engineering, Vol.118, No.2, pp. 379-397, 2021, DOI:10.32604/EE.2021.014178

Abstract In order to solve the problems of poor information flow, low energy utilization rate and energy consumption data reuse in the heavy equipment industrial park, the Internet of Things (IoT) technology is applied to construct the intelligent energy management and control system (IEMCS). The application architecture and function module planning are analyzed and designed. Furthermore, the IEMCS scheme is not unique due to the fuzziness of customer demand and the understanding deviation of designer to customer demand in the design stage. Scheme assessment is of great significance for the normal subsequent implementation of the system. A fuzzy assessment method for… More >