Operational reliability and economy evaluation of reusing retired batteries in composite power systems

2020 ◽  
Vol 44 (5) ◽  
pp. 3657-3673 ◽  
Author(s):  
Xiaolin Chen ◽  
Junjie Tang ◽  
Wenyuan Li ◽  
Le Xie
2021 ◽  
Vol 14 (2) ◽  
pp. 100-107
Author(s):  
E. M. Farhadzadeh ◽  
A. Z. Muradalyiev ◽  
S. A. Muradalyiev ◽  
A. A. Nazarov

The organization of operation, maintenance and repair of the basic technological facilities of electric power systems (EPS), which are beyond their designed service life (hereinafter referred to as ageing facilities, or AFs) is one of the problems that determine the energy security of many countries, including economically developed nations. The principal cause of insufficient overall performance of AFs is the traditional focus of the EPS management on economic efficiency and the insufficient attention to reliability and safety of AFs. The tendency to nonlinear growth in the frequency of occurrence of unacceptable consequences in the EPS requires ensuring the operational reliability and safety of AFs. The averaged estimates of reliability and safety used at designing power facilities are not suitable for characterization of overall operational performance. Among the basic and the least investigated (in terms of operational reliability and safety) EPS facilities are overhead power transmission lines (OPL) with a voltage of 110 кV and above. This is for a reason. OPL are electric power facilities with elements distributed along a multi-kilometer line (supports, insulators, wires, accessories, etc.). That is what makes the organization of continuous monitoring of the technical condition of each of these elements, and, consequently, the assessment of operational reliability and safety, so problematic. A method is suggested for assessment of “weak links” among the operated OPL on operative intervals of time along with a method for assessment of the technical condition of OPL at examination of a representative sample.


1993 ◽  
Author(s):  
Jacek Misiowiec ◽  
Tim McElwee ◽  
Sal DellaVilla

Gas turbine design evolution and practice is driven by industry demand for increased output and improved operating efficiencies. New aerothermal design characteristics require a focus on improved materials and coatings, and cooling techniques. As environmental issues continue to confront the industry, Dry Low NOx combustion system designs represent a significant opportunity for meeting new emissions requirements. These issues represent opportunity for significant technology improvements and industry driven advances. However, just as important is the design evolution of the Control and Auxiliary systems which support the gas turbine. Historically, these support systems, as demonstrated by the Operational Reliability Analysis Program (ORAP), are typically the primary drivers of plant Availability and Reliability. Following a rigorous “Design for Reliability” approach provides opportunities for ensuring that the design meets three critical requirements: starting reliability, a minimum of unit shutdowns during operating demand periods and ease of maintenance. The design approach for the Control and Auxiliary systems for new turbine design (product improvement) therefore provides an opportunity for developing a uniform and standardized approach which continues to focus on Reliability, Availability, and Maintainability. This design approach also provides opportunities for improved field installation and reduced cycle time, a major benefit for the end user. This paper will describe the “Design for Reliability” approach followed by ABB Power Generation, Inc., and supported by Strategic Power Systems, Inc.® (SPS) for the GT11N2 auxiliary systems. The extension of the ORAP system for auxiliary systems will be discussed as the approach for monitoring unit Availability and Reliability, maintaining configuration control, and for promoting continuous improvement.


Author(s):  
Dale Grace ◽  
Thomas Christiansen

Unexpected outages and maintenance costs reduce plant availability and can consume significant resources to restore the unit to service. Although companies may have the means to estimate cash flow requirements for scheduled maintenance and on-going operations, estimates for unplanned maintenance and its impact on revenue are more difficult to quantify, and a large fleet is needed for accurate assessment of its variability. This paper describes a study that surveyed 388 combined-cycle plants based on 164 D/E-class and 224 F-class gas turbines, for the time period of 1995 to 2009. Strategic Power Systems, Inc. (SPS®), manager of the Operational Reliability Analysis Program (ORAP®), identified the causes and durations of forced outages and unscheduled maintenance and established overall reliability and availability profiles for each class of plant in 3 five-year time periods. This study of over 3,000 unit-years of data from 50 Hz and 60 Hz combined-cycle plants provides insight into the types of events having the largest impact on unplanned outage time and cost, as well as the risks of lost revenue and unplanned maintenance costs which affect plant profitability. Outage events were assigned to one of three subsystems: the gas turbine equipment, heat recovery steam generator (HRSG) equipment, or steam turbine equipment, according to the Electric Power Research Institute’s Equipment Breakdown Structure (EBS). Costs to restore the unit to service for each main outage cause were estimated, as were net revenues lost due to unplanned outages. A statistical approach to estimated costs and lost revenues provides a risk-based means to quantify the impact of unplanned events on plant cash flow as a function of class of gas turbine, plant subsystem, and historical timeframe. This statistical estimate of the costs of unplanned outage events provides the risk-based assessment needed to define the range of probable costs of unplanned events. Results presented in this paper demonstrate that non-fuel operation and maintenance costs are increased by roughly 8% in a typical combined-cycle power plant due to unplanned maintenance events, but that a wide range of costs can occur in any single year.


Electronics ◽  
2019 ◽  
Vol 8 (1) ◽  
pp. 49 ◽  
Author(s):  
Dabo Zhang ◽  
Shuai Lian ◽  
Weiqing Tao ◽  
Jinsong Liu ◽  
Chen Fang

Information between interconnected power systems is difficult to share in real time, due to trade secrets and technical limitations. The regional power grid cannot timely detect the impact of changes in the operation mode of the external power grid on the regional reliability, due to faults, load fluctuations, power generation plan adjustments, and other reasons. How to evaluate the reliability of a regional power system under the conditions of information isolation is a difficult problem for the security of interconnected power systems. Aiming at this problem, an operational reliability evaluation method for an interconnected power system is proposed herein, which does not depend on external network information directly, but only uses boundary phasor measurement unit (PMU) measurement data and internal network information. A static equivalent model with sensitivity consistency was used to simplify the external network to ensure the accuracy of the reliability calculation of interconnected power systems. The boundary PMU measurement data were used to update the external network equivalent model online. The algorithm flow of the operation reliability assessment for the interconnected power grid is given. The results of an example based on the IEEE-RTS-96 test system show that the proposed method can track the equivalent parameters of the external network without depending on the actual topological information, and calculate the reliability index of the internal network accurately.


2018 ◽  
Vol 33 (4) ◽  
pp. 3691-3700 ◽  
Author(s):  
Zohreh Parvini ◽  
Ali Abbaspour ◽  
Mahmud Fotuhi-Firuzabad ◽  
Moein Moeini-Aghtaie

2017 ◽  
Vol 32 (4) ◽  
pp. 2570-2580 ◽  
Author(s):  
Chen Liang ◽  
Peng Wang ◽  
Xiaoqing Han ◽  
Wenping Qin ◽  
Roy Billinton ◽  
...  

2020 ◽  
Vol 185 ◽  
pp. 01050
Author(s):  
Yangyang Tan ◽  
Jun Liu ◽  
Sichang Xu ◽  
Peng Zhong ◽  
Qi Zhang ◽  
...  

With the penetration of renewable energy in the power system gradually increases, the importance of power electronics is growing up. The reliability of the power electronics should be taken seriously. This paper focuses on the operational reliability of photovoltaic (PV) inverters which is the most vulnerable in grid-connected PV systems and its application on the reliability evaluation of power systems. According to the field data, the effect of relative humidity is nonnegligible to the reliability of PV inverters. First, the real-time failure rate of components in PV inverters calculation method considering relative humidity is presented. Then the operational reliability evaluation of PV inverters is proposed. Finally, the reliability of power system including grid-connected PV systems is evaluated. It is aimed to explore a bottom-up approach to "effect factors-components-devices-system" reliability evaluation to establish a link between the components/devices and system. In this paper, the numerical examples verify the necessary of considering relative humidity in reliability evaluation. The evaluation results of PV inverters are used to the Roy Billinton Test System (RBTS). The analysis shows the results may affect the overall system performance.


Sign in / Sign up

Export Citation Format

Share Document