Comparison and Verification of Reliability Assessment Techniques for Fuel Cell-Based Hybrid Power System for Ships

In order to secure the safe operation of the ship, it is crucial to closely examine the suitability from the design stage of the ship, and to set up a preliminary review and countermeasures for failures and defects that may occur during the construction process. In shipyards, the failure mode and effects analysis (FMEA) evaluation method using risk priority number (RPN) is used in the shipbuilding process. In the case of the conventional RPN method, evaluation items and criteria are ambiguous, and subjective factors such as evaluator’s experience and understanding of the system operate a lot on the same contents, resulting in differences in evaluation results. Therefore, this study aims to evaluate the safety and reliability for ship application of the reliability-enhanced fuel cell-based hybrid power system by applying the re-established FMEA technique. Experts formed an FMEA team to redefine reliable assessment criteria for the RPN assessment factors severity (S), occurrence (O), and detection (D). Analyze potential failures of each function of the molten-carbonate fuel cell (MCFC) system, battery system, and diesel engine components of the fuel cell-based hybrid power system set as evaluation targets to redefine the evaluation criteria, and the evaluation criteria were derived by identifying the effects of potential failures. In order to confirm the reliability of the derived criteria, the reliability of individual evaluation items was verified by using the significance probability used in statistics and the coincidence coefficient of Kendall. The evaluation was conducted to the external evaluators using the reestablished evaluation criteria. As a result of analyzing the correspondence according to the results of the evaluation items, the severity was 0.906, the incidence 0.844, and the detection degree 0.861. Improved agreement was obtained, which is a significant result to confirm the reliability of the reestablished evaluation results.

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Real-Time Interface Model Investigation for MCFC-MGT HILS Hybrid Power System

Energies ◽

10.3390/en12112192 ◽

2019 ◽

Vol 12 (11) ◽

pp. 2192 ◽

Cited By ~ 2

Author(s):

Chen Yang ◽

Kangjie Deng ◽

Hangxing He ◽

Haochuang Wu ◽

Kai Yao ◽

...

Keyword(s):

Power System ◽

Real Time ◽

Molten Carbonate Fuel Cell ◽

Prototype System ◽

Interface Model ◽

Mass Energy ◽

Molten Carbonate ◽

Hybrid Power System ◽

Hybrid Power ◽

Energy And Momentum

The research on the control strategy and dynamic characteristics of the Molten Carbonate Fuel Cell-Micro Gas Turbine (MCFC-MGT) hybrid power system has received much attention. The use of the Hardware-In-the-Loop Simulation (HILS) method to study the MCFC-MGT hybrid power system, where the MCFC is the model subsystem and the MGT is the physical subsystem, is an effective means to save development cost and time. The difficulty with developing the MCFC-MGT HILS system is the transfer of the mass, energy, and momentum between the physical subsystem and the model subsystem. Hence, a new Simulation–Stimulation (Sim–Stim) interface model of the MCFC-MGT HILS hybrid power system to achieve a consistent mass, energy, and momentum with the prototype system of the MCFC-MGT hybrid power system is proposed. In order to validate the Sim–Stim interface model before application in an actual system, both a real-time model of the MCFC-MGT hybrid power system and the MCFC-MGT HILS hybrid power system based on the Sim–Stim interface model were developed in the Advanced PROcess Simulation (APROS) platform. The step-up and step-down of the current density, which were strict for the Sim–Stim interface model, were studied in these two models. The results demonstrated that the Sim–Stim interface model developed for the MCFC-MGT HILS hybrid power system is rapid and reasonable.

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Parametric Analysis of Hybrid MCFC Micro Gas Turbine System

Volume 5: Turbo Expo 2005 ◽

10.1115/gt2005-68655 ◽

2005 ◽

Author(s):

Hongliang Hao ◽

Huisheng Zhang ◽

Shilie Weng ◽

Ming Su

Keyword(s):

Power Generation ◽

Fuel Cells ◽

Power System ◽

Gas Turbine ◽

Molten Carbonate Fuel Cell ◽

Design Parameters ◽

Molten Carbonate ◽

Hybrid Power System ◽

Micro Gas Turbine ◽

Hybrid Power

Fuel cells have been revealed to be a very attractive power generation system, promising highly efficient electricity generation and very low environmental impact. The integration of micro turbines and high-temperature fuel cells has been proposed in recent years as an extremely efficient solution for power generation. A molten carbonate fuel cell / micro gas turbine (MCFC/MGT) hybrid power system has theoretically demonstrated that it can achieve higher thermal efficiency than other conventional power generation systems. To understand operation characteristics of the MCFC/MGT hybrid power system, it is essential to analyze influence of operating and design parameters on its performance. Based on an existing 50KW MCFC stack, a steady-state thermodynamic model for MCFC/MGT hybrid power system is developed on the IPSEpro simulation platform and applied to a performance analysis. The characteristics under off-design and design condition for hybrid power system were also analyzed.

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Research of the Power Control for a MCFC/GT Hybrid System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.860-863.2596 ◽

2013 ◽

Vol 860-863 ◽

pp. 2596-2599

Author(s):

Fan Yang ◽

Hua Xue ◽

Hao Li

Keyword(s):

Power System ◽

Hybrid System ◽

Control Method ◽

Molten Carbonate Fuel Cell ◽

Support Vector ◽

Molten Carbonate ◽

Hybrid Power System ◽

Feed Forward Control ◽

Hybrid Power ◽

Carbonate Fuel Cell

Molten carbonate fuel cell/ gas turbine hybrid power system (MCFC/GT) output power should real-time response the demand of load. The auto-tuning ZieglerNichols tuned PI controller (AZNPIC) as a feedback controller for power corrective action is added to the hybrid power system. The optimal setpoints and feed forward control inputs of the controller are given by Multi-output Support Vector Machine Regression (MSVR) predictor for the hybrid system. Simulation results show that the power of hybrid system can be effectively close to the desired setpoints based on the control method.

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Optimization of the Fuel Cell Renewable Hybrid Power System Using the Control Mode of the Required Load Power on the DC Bus

Energies ◽

10.3390/en12101889 ◽

2019 ◽

Vol 12 (10) ◽

pp. 1889 ◽

Cited By ~ 8

Author(s):

Nicu Bizon ◽

Valentin Alexandru Stan ◽

Angel Ciprian Cormos

Keyword(s):

Energy Source ◽

Fuel Cell ◽

Power System ◽

Control Mode ◽

Variable Load ◽

Hybrid Power System ◽

Hybrid Power ◽

Load Power ◽

Load Demand ◽

Dc Bus

In this paper, a systematic analysis of seven control topologies is performed, based on three possible control variables of the power generated by the Fuel Cell (FC) system: the reference input of the controller for the FC boost converter, and the two reference inputs used by the air regulator and the fuel regulator. The FC system will generate power based on the Required-Power-Following (RPF) control mode in order to ensure the load demand, operating as the main energy source in an FC hybrid power system. The FC system will operate as a backup energy source in an FC renewable Hybrid Power System (by ensuring the lack of power on the DC bus, which is given by the load power minus the renewable power). Thus, power requested from the batteries’ stack will be almost zero during operation of the FC hybrid power system based on RPF-control mode. If the FC hybrid power system operates with a variable load demand, then the lack or excess of power on the DC bus will be dynamically ensured by the hybrid battery/ultracapacitor energy storage system for a safe transition of the FC system under the RPF-control mode. The RPF-control mode will ensure a fair comparison of the seven control topologies based on the same optimization function to improve the fuel savings. The main objective of this paper is to compare the fuel economy obtained by using each strategy under different load cycles in order to identify which is the best strategy operating across entire loading or the best switching strategy using two strategies: one strategy for high load and the other on the rest of the load range. Based on the preliminary results, the fuel consumption using these best strategies can be reduced by more than 15%, compared to commercial strategies.

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