Service Reliability

2016 ◽  
pp. 599-642
Keyword(s):  
Service Reliability

scholarly journals A Bus-Sectionalized Hybrid AC/DC Microgrid: Concept, Control Paradigm, and Implementation

Energies ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3508
Author(s):  
Jing Li ◽  
Hongda Cai ◽  
Pengcheng Yang ◽  
Wei Wei
Keyword(s):  
Hierarchical Control ◽  
Mode Switching ◽  
Stable Operation ◽  
Service Reliability ◽  
Test Results ◽  
Dc Microgrid ◽  
Dc Microgrids ◽  
Operation Modes ◽  
Control Paradigm ◽  
Operational Data

In the last several years, the coordination control of hybrid AC/DC microgrids (HMGs) has been gaining increasingly more attention. However, most of these discussions are focused on single-bus HMGs whose AC or DC bus is not sectionalized by AC or DC breakers. Compared with these single-bus HMGs, the bus-sectionalized HMG has more flexible topologies, more diverse operation modes, and consequently higher service reliability. However, meanwhile, these benefits also bring challenges to the stable operation of bus-sectionalized HMGs, particularly for mode switching. Relying on the national HMG demonstrative project in Shaoxing, China, this paper makes efforts to present the hierarchical control paradigm of a typical bus-sectionalized HMG toward standardization. The test results demonstrate that the proposed system provides seamless switching and uninterrupted power supply without controller reconfiguration among different operation modes. The operational data are also brought forth and analyzed to provide significant and useful experiences for designing and developing similar HMGs in the future.

Evaluation of urban bus service reliability on variable time horizons using a hybrid deep learning method

2022 ◽  
Vol 217 ◽  
pp. 108090 ◽  
Author(s):  
Tuqiang Zhou ◽  
Wanting Wu ◽  
Liqun Peng ◽  
Mingyang Zhang ◽  
Zhixiong Li ◽  
...  
Keyword(s):  
Deep Learning ◽  
Service Reliability ◽  
Learning Method ◽  
Variable Time ◽  
Time Horizons ◽  
Urban Bus ◽  
Bus Service

In-Service Reliability Assessment of Turbine Blade Thermal Barrier Coatings Based on a Novel Cumulative Damage Index Model

2021 ◽  
Author(s):  
He Liu ◽  
Jianzhong Sun ◽  
Shiying Lei
Keyword(s):  
Damage Index ◽  
Cumulative Damage ◽  
Life Assessment ◽  
Thermal Barrier ◽  
Inlet Temperature ◽  
Service Reliability ◽  
Engine Operation ◽  
Premature Failure ◽  
Covariate Data ◽  
Index Model

Abstract Thermal barrier coating (TBC) has been used widely on turbine blades to provide temperature and oxidation protection. With the turbine inlet temperature continuously increasing, TBCs have become more likely to oxide spallation, leading to premature failure of blade metal substrates. Thus, It is necessary to accurately evaluate the in-service reliability of TBCs for blade life assessment and engine operation safety. Nowadays, it is common to dynamically record aero-engine operating and performance data, called dynamic covariate data, which provides periodic snapshots for obtaining reliability information of engine components. Nevertheless, existing TBC life prediction models that pay adequate attention to dynamic covariate information are rare. This paper focuses on using limited failure samples with associated dynamic covariate data to make in-service reliability assessments of TBCs through a proposed cumulative damage index model. For the demonstration of the proposed approach, an integrated TBC life simulation approach has been introduced, which comprises engine performance, blade thermal, TBC damage, and damage accumulation models. The case study shows that the proposed cumulative damage index model based method provides more stable and accurate results than the traditional statistical method based on failure-time data.

Characterization of gas turbine ingested sand particles based on electrostatic signal

2021 ◽  
pp. 095765092110464
Author(s):  
Jianzhong Sun ◽  
Heng Jiang ◽  
Caiqiong Yang ◽  
Ruochen Liu
Keyword(s):  
Theoretical Analysis ◽  
Gas Turbine ◽  
Simulation Study ◽  
Aircraft Engine ◽  
In Situ Monitoring ◽  
Service Reliability ◽  
Fem Modeling ◽  
Initial Development ◽  
Sand Particles ◽  
Particle Ingestion

Particle ingestion into a gas turbine can have serious effects on both performance and engine in-service reliability. Thus there exists a need for in situ monitoring and characterizing particulate matter entering an aircraft engine inlet for the purposes of engine damages estimation and prognosis. This paper presents the initial development of Ingested Debris Monitoring System (IDMS) signal processing method of characterizing the ingested particles. A theoretical analysis and simulation study were carried out to study the relationships between the characteristics of the ingested sand particles and the features of the IDMS signal both in frequency- and time-domain. A Finite-Element Modeling (FEM) for the IDMS Sensor was developed, then the validated FEM modeling was used for simulation experiments of particles ingestion under various conditions of different particle moving speeds, concentrations and charge-to-mass ratios. Results of the theoretical analysis and simulation study demonstrates the feasibility and effectiveness of the proposed method to provide real time information characterizing the size and concentration of ingested sand particles, and will serve as an impetus to carry out further research.

Zone Scheduling of Bus Routes to Improve Service Reliability

1979 ◽  
Vol 13 (3) ◽  
pp. 242-268 ◽  
Author(s):  
William C. Jordan ◽  
Mark A. Turnquist
Keyword(s):  
Service Reliability
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