In this work, a residential-based PEMFC-CHP (proton exchange membrane fuel cell based combined heat and power) system is established and studied by MATLAB/Simulink. The effects of thermal resistance, ...hydrogen and oxygen inlet pressure, PEMFC output power, and cooling water flow on the system performance were systematically studied. The results show that with the increase of the hydrogen and oxygen inlet pressure, PEMFC stack power, and cooling water flow, the CHP system efficiency is improved. Meanwhile, the increased thermal resistance results in less heat dissipation radiating into the air and the CHP system efficiency is also improved. When the thermal resistance of PEMFC reaches 0.2 K/W, the CHP system efficiency is as high as 85.86%. Finally, a case study was conducted on a residential-based CHP system and the operation characteristic curve of the system is obtained. The system is able to recover as much heat as possible while maintaining the residential electricity demand.
This paper presents a physics-based mathematical model for a fuel cell hybrid vehicle system. The performance design of fuel cell hybrid electric vehicles (FCHEVs) is an area of interest in ...transportation applications. FCHEV is a combination of a proton exchange membrane fuel cell (PEMFC), with a battery and associated DC/DC and DC/AC converters. Suitable batteries are used in FCHEV acts as a backup system with efficient energy management. The battery is designed for fast power transfer during transient response and constant performance without hydrogen. The power management schemes discussed are consistent with the most common modern power management techniques used in fuel cell vehicle applications, including: the state engine control strategies, rule-based fuzzy logic strategies, classical proportional integral control strategies, frequency fuzzy logic decoupling/control minimization strategies. Therefore, we tested and evaluated the reliability of the model using the MATLAB/Simulink environment, with mixed results.
The maintenance of railway infrastructure plays a critical role in ensuring the optimal availability and safe operation of railway tracks and associated equipment. Nevertheless, the preservation of ...train power transmission lines presents noteworthy hazards as a result of the amalgamation of electrical perils and maintenance-associated risks. This study aims to present the design and simulation of a planar translational scissor lift mechanism. The objective is to assist maintenance personnel in the rail sector specifically during power transmission line maintenance. The scissor-lifting mechanism was modelled in Solid Works, a software programme known for its comprehensive 3-D modelling capabilities. Additionally, a mathematical model was constructed to analyse the behaviour of the scissor lift. The dynamic response of the system was investigated through the utilisation of MATLAB/Simulink to conduct kinematic and kinetic simulations. The research findings unveiled the comparative kinetic correlation between the hydraulic cylinder and other constituent elements, effectively capturing their dynamic behaviours throughout the operational process. In addition, the utilisation of Simscape facilitated the optimisation of the mechanism's design through simulation analysis, thereby offering valuable insights to inform and improve subsequent design iterations. The experimental findings indicate that the system design effectively raised the maintenance platform to a height of 2 metres in a time of 20 seconds while accommodating a load range of 500 to 1000 kg. The study presents a systematic and logical design approach that establishes a scientific foundation for the mechanism. This positions it as a valuable theoretical reference for future advancements in scissor lift development. The results of this study make a valuable contribution towards enhancing safety and efficiency in rail maintenance operations. Additionally, they help in reducing the risks associated with power transmission line servicing. Furthermore, these findings lay the foundation for future advancements in railway maintenance technology.
The desire to reduce pollution and price instability generated by the major share of fossil fuel use requires firm solutions for ecological transition of the economy, which must provide access to ...clean, safe and affordable energy. An important, seriously affected sector, being a competitive field with consistent limitations, is the transport system, where the use of alternative fuels or the use of electric cars is definitely a solution. The present paper presents an evaluation, through simulation in MATLAB-Simulink, of influence of parameters such as: vehicle frontal area, tire pressure, wind speed, road slope, aerodynamic coefficient and rolling resistance coefficient, in the power and energy balance and aspects that influence the optimal dimensioning of batteries and electric motor.
•The two-bed advanced thermophysical battery is intended to accomplish semi-continuous operating and refrigeration.•A compact advanced thermophysical Battery is provided by combining the evaporator ...and condenser in one heat exchanger.•The lumped parameter method (LPM) and modified Freundlich adsorption equations are used for developing a theoretical design.•Modern air conditioner systems that use waste heat driven instead of mechanically driven.
Air conditioning systems powered by waste energy sources, such as solar-driven adsorption air conditioning systems, hold significant importance. The present study delves into the performance assessment of a silica gel-based adsorption thermophysical battery (ATB) under varying operational conditions. Advanced cycles featuring a two-bed configuration have been devised to enable semi-continuous operation and refrigeration. This novel design presents a compact ATB that integrates the evaporator and condenser within a single heat exchanger, referred to as the Evaporator-Condenser Unit (ECU), thereby reducing the overall size and cost of the ATB system. The operating and design characteristics of the two-bed adsorption system were thoroughly explored using a theoretical model developed through MATLAB software. Evaluations were conducted on various performance metrics of the ATB, encompassing the coefficient of performance (COP), cooling capacity, specific cooling power, adsorption isotherm, and kinetics. A theoretical approach was formulated using the lumped parameter (LPM) and modified Freundlich adsorption equations. It can be deduced that the inlet temperature of the hot coolant exhibited a direct proportion with both refrigeration effect (RE) and specific cooling power (SCP) while inversely affecting the coefficient of performance (COP). A decrease in coolant temperature from 313 to 303 K resulted in a noteworthy 13.4%. Furthermore, it was observed that COP exhibited a direct proportionality with the flow rate of chilled and cooled water while inversely relating to the flow rate of hot water.
The paper describes methods of simulation conduction and switching losses of power semiconductors in MATLAB/Simulink. The comparison of simulation results for Infineon’s semiconductor with PLECS ...Standalone simulation is presented. The results show that the simple ideal switching model of the IGBT in Simulink gives similar results to the PLECS simulation with the Infineon PLECS library.
•A process of packaging and drum generation of radioactive waste was implemented using Matlab/Simulink.•An algorithm was designed to optimize the repackaging of radioactive waste.•6 scenarios were ...constructed and analyzed according to the confidence interval, the optimization algorithm and repackaging methods.•The amount of radioactive waste was predicted by repackaging simulation.
This study implemented a packaging and drum generation process for radioactive waste using Matlab/Simulink. The simulation was based on the regulations of field work, and aimed to derive the optimal repackaging method by adjusting the constraints. We analyzed the radioactive waste nuclide concentration, weight, and small package amount as constraints and also analyzed the number of drums for each radioactive level generated according to the scenarios. The radioactive waste repackaging process simulation was designed to analyze cases according to the confidence interval, and the optimization algorithm to reduce the number of radioactive waste drums was analyzed while checking the change in the number of drums according to the repackaging scenario. Simulation analysis can be used for radioactive waste management and analysis, decision-making, and generation prediction, and through systematic management, the safety and economic efficiency of radioactive waste management can be expected.
The optimization of energy consumption in buildings’ HVAC systems plays a crucial role in reducing greenhouse gas emissions worldwide. In new and deeply-renovated buildings, characterized by ...modulating terminal units and aiming at the maximum exploitation of renewables, an accurate hydraulic balance of the distribution network may become critical, resulting in a significant increase of pumping energy consumptions and a deterioration of indoor thermal comfort conditions. In the present paper, we compare the performance of traditional manual balancing valves and new pressure independent control valves (PICVs), used to balance the hydronic loop of HVAC systems. To perform this analysis, a new MATLAB-Simulink model has been specifically developed to simulate the behavior of PICVs and has been used in an application case study. The efficiency of manual and pressure independent control valves is evaluated numerically by simulating a multi-zone distribution network under variable operating conditions and considering different control strategies of the circulating pump. Results show that in off-design conditions, when some of the branches of the hydraulic network are closed, traditional manual balancing valves are not able to guarantee the nominal mass flow rate in the remaining loops. On the contrary, no significant variations of water mass flow rate are observed when PICVs are adopted, even in partial load conditions. Despite their additional cost, PICVs allow to ensure better indoor thermal comfort sensations for individuals, avoiding under/over-heating of rooms and, moreover, yield a decrease of the pump electric consumption with respect to traditional manual balancing valves. In addition, based on the obtained results, general rules concerning the adoption of PICVs are provided, depending on the extension of the hydraulic loop and the adopted pump control logic. The reported results highlight the role that PICVs can play to ensure energy savings in HVAC systems without penalizing users’ indoor comfort conditions.
This work presented a self-excited induction generator (SEIG) model controlled by an (FC-TCR) fixed capacitor-thyristor control reactor consisting of a large fixed capacitor in parallel with a ...thyristor controlled reactor in series with the constant inductance. Induction machines were used because they are capable of working at different speeds. The 3-phase IG was driven by the prime mover that represents the wind turbine. Also, constant voltage and frequency were obtained, regardless of the change in velocity, by using proportional integration (PI control) for each of them. This type of generator is used in isolated rural areas far from power transmission lines. The voltage and frequency are analyzed for each wind speed proposed in the model and calculating the required excitation amplitude and torque required to drive the induction generator. Therefore, it is now a key interest to develop an efficient, viable, economic, and controllable induction generator for harnessing energy from renewable sources. The strategy of control was implemented with MATLAB/Simulink.
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