Independent Power Generation System Research Articles

Research on Solid Oxide Fuel Cell System Model Building and 3D Testing Based on the Nodal Idea

The Solid Oxide Fuel Cell (SOFC) system is a highly intricate system characterized by multiple variables and couplings. Developing an accurate model for the SOFC independent power generation system is of paramount importance. Conducting experimental studies on the SOFC system is costly, and it carries certain risks due to the requirements for pure hydrogen, high-temperature environments, and other factors. To address these challenges, a high-performing model that precisely reflects the inherent characteristics of the SOFC is essential for dynamic static analysis and the identification of optimal operating points. This paper presents a SOFC system model based on current controls, which was implemented in the MATLAB/Simulink environment, and it utilized a nodal approach for modeling. The model incorporated a cold air bypass, which enabled the more precise control of the SOFC reactor’s inlet and outlet temperatures. Furthermore, a 3D test and verification method are proposed in order to focus on the influence of input parameters on the four electrical characteristics, and four thermal characteristics, of output parameters. By conducting one-dimensional, two-dimensional, and three-dimensional studies of these output parameters, a more intuitive understanding of the system’s response to changes in input parameters was obtained. Under conditions wherein all other variables were kept constant, the entire system attained its maximum efficiency at approximately FU = 0.8, BP = 0, and AR = 6. The outcomes of this study have significant implications for exploring the optimal operating point in the SOFC independent power generation system in an in-depth manner. It provides valuable insights for enhancing the system’s efficiency and performance.

Analysis and research on the thermal system of waste incineration power generation unit based on heat balance method

The thermal system of waste incineration power generation unit is simple and small in capacity, but the original parameters are few. It needs to calculate the thermal system and derive the parameters by using the conventional heat balance method to obtain the complete thermal system parameters. In this paper, an accurate and perfect thermodynamic model of waste incineration power generation is established to solve the problems of low thermal efficiency and high unit investment cost of the waste incineration power generation. To investigate the internal relationship between the incinerator unit structure, operating parameters, waste calorific value and waste combustion process, optimize the combustion status of different incinerators burning different waste, and realize its stable and efficient operation, it is necessary to study the impact of changing operating parameters and different incinerator structures on the waste incineration process, as well as the incineration law of a single incinerator unit structure burning waste with different calorific value. Based on the two-fluid model of primary oxygen supply and secondary oxygen supply, a newly developed thermodynamic model for waste incineration engineering was developed, and the direct coupling between the reciprocating grate and the incinerator was realized in the software. Using the conventional heat balance method and constant flow calculation, the flow parameters of the thermal system under the design condition are calculated through the design pressure parameters to calculate the power generation and thermal economy index of the condition; and the relevant steam extraction flow is checked and verified. The experimental results show that the net thermal efficiency of waste incineration increases from 19. 73% to 26. 40%, and the energy utilization efficiency also increases by 0. 18%. The net thermal efficiency of the optimized integrated power generation system is always higher than that of the independent power generation system more than 0.16%. The model method used in this paper can reduce the influence of incinerator arch structure on bed combustion to a greater extent, which makes the simulation results close to reality, greatly reduces the calculation cost, and is conducive to the industrial application of simulation in the field of waste incineration.

Performance analysis of fuel vapor turbine and closed-Brayton-cycle combined power generation system for hypersonic vehicles

One of the most important targets is the power supply issue in hypersonic propulsion systems with long range/endurance. Due to the lack of rotating components and aerodynamic loss using the free stream, existing technologies of onboard power generation are hardly applicable on hypersonic vehicles using scramjets. A combined power generation system based on fuel vapor turbine (FVT) and closed-Brayton-cycle (CBC) is proposed in this article. To evaluate the system performance, a zero-dimensional model is established, and an optimization method based on genetic algorithm is developed to obtain the maximum electric power. Results indicate the increase of the compressor pressure ratio has the most significant effect on rising the electric power. And the effect of the FVT expansion ratio becomes significant when the FVT isentropic efficiency gets high. Furthermore, due to the utilization of the fuel vapor pressure energy by the FVT, the electric power of the FVT-CBC combined system is higher than that of the CBC independent power generation system, with a rise percentage of 25%–190%. After optimization, the maximum electric power of the combined system can be 326.7 kW. In a word, the FVT-CBC combined power generation system can supply sufficient power for hypersonic vehicles.

Speed sensorless direct voltage control of brushless doubly-fed machine independent generation system based on improved particle swarm optimization algorithm

The speed information is obtained by sensors in the control strategy of brushless doubly-fed machine (BDFM) independent power generation system. However, the use of sensors increases the hardware cost of the system, reduces the reliability and the sensors are difficult to adapt to the harsh environment such as high temperature and high humidity. In order to solve the above problems, a speed sensorless direct voltage control method for brushless doubly-fed machine independent generation system is proposed. At the same time, in order to improve the control quality, the improved particle swarm optimization algorithm is used to optimize the control parameters of the system. Simulation results show that the BDFM independent power generation system can still maintain excellent performance and can meet the performance requirements in various operating conditions with the control method proposed in this paper.

Application of ORC in a Distributed Integrated Energy System Driven by Deep and Shallow Geothermal Energy

This study presents a distributed integrated energy system driven by deep and shallow geothermal energy based on forward and reverse cycle for flexible generation of cold, heat and electricity in different scenarios. By adjusting the strategy, the system can meet the demand of heat-electricity in winter, cool-electricity in summer and electricity in transition seasons. The thermodynamic analysis shows that the thermal efficiency of the integrated energy system in the heating and power generation mode is 16% higher than that in the cooling and power generation mode or the single power generation mode. Meanwhile, the annual heat-obtaining quantity of the system is reduced by 11% compared with that of the independent power generation system, which effectively alleviates the imbalance of the temperature field of the shallow geothermal reservoir. In terms of net power generation, the integrated energy system can generate approximately 31% more electricity than the conventional independent cooling and heating system under the same cooling and heating capacity. An integrated system not only realizes the comprehensive supply of cold and thermal ower by using clean geothermal efficiency, but also solves the temperature imbalance caused by the attenuation of a shallow geothermal temperature field. It provides a feasible way for carbon emission reduction to realize sustainable and efficient utilization of geothermal energy.

Hybrid nuclear-renewable energy systems: A review

Abstract Climate change and energy security have emerged as the biggest concerns of the present century. Renewable energy sources are not continuous, dependent upon geographical location as well as climatic conditions, and require a very large land footprint. Future of nuclear energy is also uncertain because of public apprehensions and subsequent government policies. To overcome the issues derailing these two virtually carbon-free energy sources, a new hybrid or integrated nuclear-renewable energy system is being proposed and seen as an attractive option. Such integrated energy systems are conceived as a nuclear power reactor coupled with renewable energy generation and industrial processes that may simultaneously tackle the concerns regarding grid flexibility, climate change, energy security, optimal return on invested capital, and settling public concerns. Apart from highlighting the key challenges associated with nuclear energy and renewable energy sources while operating as an independent power generation system, the present paper delineates the various aspects associated with integrated nuclear-renewable energy systems. It may be speculated that integrating nuclear energy and renewable energy into a single hybrid energy system, coupled through informatics linkages, would enable to overcome the demerits present when they operate individual.

Measuring and reconstruction algorithm based on improved second‐order generalised integrator configured as a quadrature signal generator and phase locked loop for the three‐phase AC signals of independent power generation systems

In an independent power generation system, the amplitude and frequency of the power generation voltage are easily affected by the fluctuation of the external load and harmonic pollution. The power quality may also be reduced by relatively imprecise measurements. In this regard, a measuring and reconstruction algorithm based on an improved second-order generalised integrator configured as a quadrature signal generator (SOGI-QSG) and phase locked loop (PLL) for three-phase alternating current signals has been proposed in this study. The amplitudes and direct current components of the measured signals are obtained from three SOGI-QSGs. The inverse function of sine is introduced to optimise the phase error that has been used to quickly acquire fundamental frequency and phase of the measured signals. Moreover, the phase sequence of the measured signals is determined by the sign function. Compared with a traditional dual second order generalised integrator PLL, quick responses and reconstruction performances of the proposed algorithm are validated by experiments.

Self-Sustained, Independent Trifold Solar Energy Conversion System for Isolated Locations in Hot Climate Areas

This paper proposes two configurations for a hybrid solar energy conversion device that can be used as a self-sustained, independent power generation system in isolated locations in hot climate areas. Given the strong dependence of photovoltaic cell conversion efficiency on operation temperature, the cooling of the backside becomes imperative, increasing not only electrical, but also the overall solar energy conversion efficiency. The hybrid system provides now electricity and hot hater for domestic applications. To further improve electrical efficiency, a thermoelectric generator module is added to the system, harvesting the thermal energy that otherwise would be regarded as waste heat and rejected to environment. The optimization of the parameters that influence the total efficiency demonstrate the strong connection between the three parts of the system, PV-TE-DHW.

Reliability assessment for components of large scale photovoltaic systems

Photovoltaic (PV) systems have significantly shifted from independent power generation systems to a large-scale grid-connected generation systems in recent years. The power output of PV systems is affected by the reliability of various components in the system. This study proposes an analytical approach to evaluate the reliability of large-scale, grid-connected PV systems.The fault tree method with an exponential probability distribution function is used to analyze the components of large-scale PV systems. The system is considered in the various sequential and parallel fault combinations in order to find all realistic ways in which the top or undesired events can occur. Additionally, it can identify areas that the planned maintenance should focus on. By monitoring the critical components of a PV system, it is possible not only to improve the reliability of the system, but also to optimize the maintenance costs. The latter is achieved by informing the operators about the system component's status. This approach can be used to ensure secure operation of the system by its flexibility in monitoring system applications. The implementation demonstrates that the proposed method is effective and efficient and can conveniently incorporate more system maintenance plans and diagnostic strategies.

Power Grid and Alternating Current Distribution Research of Renewable Energy Generate Electric Power's Village System

Renewable energy which independent power generation systems from the nets is increasingly extensive research and application. This paper is in connection with ac distribution problems of village, it is with the foundation of multiple national's standard and field operation experience. From lines in-station, transmission and distribution line, distribution cabinets and other power distribution equipment structure, function, capacity selection, and so on, this paper has a positive research summary and elaboration, can provide the beneficial reference for relevant standards.