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Ramp rates of generators are generally specified within elastic range of the strength of the shaft to safeguard the rotor from fatigue. These limits can, however, be exceeded, albeit at the risk of reducing the rotor life. Such effects on the rotor life can be compensated by incorporating appropriate ramping costs. Power demand and power price in deregulated power markets have shown a tendency of sudden wide excursions over short intervals of time. The ability to respond to such fast change in demand and price can be quite rewarding. This provides the motivation to utilize the ramping rates beyond traditional elastic limits. This paper studies the strategic use of ramping rates beyond elastic limits in a power producer's self-dispatch in a power market with price and demand volatility. A set of ramping processes has been developed from ramping-cost versus ramping time relationships to derive the total operation cost including ramping costs for various levels of ramping rates exceeding elastic limits. A thorough theoretical analysis has been conducted for the selection of the optimal ramping process under different conditions. A numerical example is presented to highlight the potential benefits from the optimal use of these ramping processes. It is seen that the benefit from the strategic use of ramp rates beyond elastic limits not only depends on the high price in the power market but also on the initial loading of the generator which limits the capacity available for dispatch. Index Terms--Power dispatch, power market, ramp rates, ramping cost, ramping process.

Performance evaluation of a combined generation and transmission system normally includes the independent outages of generators, transformers and transmission lines. However, substation originated outages due to failure of breakers, transformers and busbars can also have a significant effect on the bulk power system performance indices in terms of outage frequency and duration. The studies described in this paper utilized various substation components such as breakers, busbars and transformers to develop a general-purpose software to assess the reliability of the system. It performs failure modes and effect analysis and provides a concise and orderly description of the various combinations of occurrences within a system that could result in an interruption of supply. Reliability analysis technique using the minimal cut set method has been implemented. In addition the software package is able to define and incorporate 15 types of system configurations in the analysis and at the same time, comprehensive analysis tools such as print, save, sensitivity studies, tutorial guide, etc., are also included. The concept associated with the reliability analysis is illustrated by application to a simple but comprehensive system configuration. Keywords: Substation reliability; Software development; Reliability analysis

This paper presents a system well-being evaluation method that divides the composite power system operating condition into several states depending on the level to which the adequacy and security constraints are satisfied. Conventional composite system reliability indices typically do not reflect the ability of the system to withstand, without resulting in load curtailment or other violations, the abrupt loss of system components. The well-being evaluation method provides an extra index for system planners or designers to decide whether or not the power system is capable, based on the deterministic criteria, to withstand unplanned outages of system components without violation of specified constraints. The well-being indices, which are the probabilities of the system being in the healthy, marginal and at risk states, provide this important and intuitively interpretable information for system planning and operations. Studies on two test systems were done to examine the effect of load levels, system component removal and addition on the well-being indices. The bus well-being indices for selected buses of the two test systems were also calculated and compared with the system well-being indices. Keywords: Composite systems; Well-being analysis; Adequacy assessment; Health analysis; Deterministic criteria

One major application of photovoltaic(s) (PV) power has been in remote areas as isolated small power generation for essential electric power. This paper discusses issues in optimizing the use of such stations and presents a procedure to evaluate different PV schemes considering the stochastic natures of the insolation and the load. The reliability measures in terms of loss of load hours (LOLH), the energy loss and the total cost have been used as the indices for evaluation of different schemes. The insolation and the load demand are modeled as stochastic variables using historical data and experimentation respectively. The operation of various stand-alone schemes are simulated for a specific load. Actual commercially available panel and battery sizes with actual costs have been used in the various configurations studied. The long run expected values of the performance indices for various configurations of the solar station have been measured. Comparative analysis of the results show that higher cost not necessarily translates into better performance. The panel size and the battery size have different impacts on the indices of performance, and a proper balance between the two is necessary to optimize the operation of a stand-alone PV scheme. Keywords: Photovoltaic(s) power, Stand-alone scheme, Simulation, Optimization of solar power.

The basic concepts associated with quantitative reliability assessment of electric power systems are reasonably well established and well accepted by the power industry. The evaluation of the costs and benefits of competing investments is now becoming a standard practice in power system planning. The justification of new facilities and system modifications now normally includes specific reference to reliability and one approach that is receiving considerable attention is the evaluation of the societal worth (benefit) of system reliability, or conversely the costs incurred by consumers due to power supply interruptions. In order to make a consistent appraisal of economics and reliability, it is imperative to compare the investment cost needed to attain a specified level of reliability with the reliability worth or benefits derived by the society at that level of system reliability. This paper discusses the developments made in existing techniques in the area of power system reliability cost/benefit evaluation and application. Reliability worth data presently used in cost/worth evaluation are presented, and their applications in conjunction with the system reliability indices are also presented in this paper. Keywords: Reliability cost; Reliability worth; Customer survey; Outrage costs; Value-based reliability; Power system reliability; Worth of supply; Supply reliability

This paper presents an educational software package that was developed for conducting sub-transmission system adequacy studies. The fundamental objective of the developed software is to simulate the basic system failure modes and assess the impact that fluctuating weather conditions have on a system's overall reliability. Due to obvious advantages, the failure modes and effects analysis was implemented as the key evaluation technique. Two sets of indices, the basic load point and system performance indices, are used to assess the reliability. A series of studies were conducted using the developed software on a test system designated RBTS. Selected results from these studies are presented in the paper. Keywords: Sub-transmission system, adequacy assessment, interactive software.

This paper describes the main features of four design modules that form part of the curriculum for the final year power engineering students at the Nanyang Technological University, Singapore. Through the use of these modules, the students gain an insight into the various aspects of power engineering including power electronics and drives - and this will hopefully help them in a better understanding of the practical aspects of power engineering, and therefore make them better engineers in the power industry. The four modules described are Generating Capacity Expansion Planning, Rectifier and DC Motor Control, Power Systems Operations Planning, and Security Enhancement using Optimal Power Flow. Keywords: power system design, power engineering education, undergraduate curriculum, power system planning.

There is an ever growing demand to justify reliability projects on a more quantifiable basis, i.e. investments related to the provision of service reliability needs to be carefully evaluated in regard to their cost and benefit implications. In addition, utilities are recognizing the significant customer and community costs that are incurred when electric supply is abruptly curtailed. Consequently, the utility industry is under pressure to assess their reliability evaluation tools and formulate methods for incorporating the economics of reliability in the decision-making process. This paper is concerned with the evaluation of a reliability worth index that can be used to make decisions in distribution system planning and design. The reliability worth index is termed the interrupted energy assessment rate (IEAR) and is obtained by relating the reliability indices to the customer cost of interruption data. Three fundamentally different approaches for evaluating distribution system reliability worth indices are presented and compared using a small but comprehensive test system. The impact on the worth indices of distribution system operating policies and configurations is also illustrated using the three methods. The worth indices developed can be used to determine the monetary implications of customer supply interruptions thereby incorporating economics in the reliability cost-benefit equation.

Power system planning is concerned both with the level of predicted reliability and the investment/operation alternatives associated with satisfying the desired level. The total societal cost consist of costs associated with required investments and operation of the system and the customer unsupplied energy costs due to electric supply interruptions. The predicted system reliability in quantitative terms and the consumer costs associated with supply interruptions can be used to compute the customer unserved energy costs. This association is formed by the development of a reliability worth factor designated as the interrupted energy assessment rate (IEAR). This paper shows how IEAR can be utilized in a generating capacity adequacy study, composite system adequacy study and at each individual customer load point and/or sectors within the overall electric power system in an assessment of the monetary worth of reinforcements.

When a utility buys electric energy from a non-utility generation (NUG) at short notice, such as a few hours, one of the most difficult issues encountered by the utility is the evaluation of the rate (buyback rate) it should pay the NUG such that the utility maximizes its economic benefits. Utilities calculate their purchase rates based on a number of different formulae. Short term buyback rates should be based on the operating cost that a utility avoids by utilizing energy from a NUG. This cost is termed as the avoided operating cost (AOC) in this paper. This paper illustrates a technique, which can be utilized to evaluate the AOC under different operating conditions in a just and reasonable fashion and that can be verified by both the utility and the NUG. Significant aspects of NUG are examined and discussed in this paper using a small test system. Sensitivity studies, similar to those illustrated in this paper, can be utilized to estimate the savings in the running cost incurred by a utility when it buys electrical energy from NUG. [C] 2001 Elsevier Science Ltd. All rights reserved. Keywords: Avoided operating cost; Non-utility generation; Composite system; Generation and transmission planning; Operating reserve

Internet of things (IoT) is a system of "Smart Devices" used over the internet through the world were it will sense and connect with our environment and involves with humans and it is a user friendly for the users and another system devices. Air pollution is one of the major issue of our generations. The rate of air pollution gradually increases with time by more number of things like increasing in vehicles, increasing in population, urbanization, industrialization which helps up in harmful disease effect on human life by directly effecting health of country exposed to it .Air quality gets decreases when enough amount of toxic gases in the atmosphere like co2,alchol,smoke,nh3,benzen and no2.In order to survey we are deploying IoT based pollution monitoring system Were it will capture all the air quality over an cyber space .existing monitoring system and no sensitivity and need technical analysis. So improvement of monitoring system are requires. To Control the issue of trending system. We propose a pollution monitoring system it will detect the percentage of pollution in our environment it shows the average density of pollution released by vehicles or any industries etc.If the pollution level get cross by average it may cause more danger to our human health.