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The use of alternate fuels and raw materials in the cement manufacturing process has evolved substantially over the last two to three decades, along with approaches to acquire regulatory approval. Most recently, the Environmental Protection Agency (EPA) has published new regulations as an overlay to what has been in place, having the potential to significantly impact this practice. Instead of dealing with the state agencies that usually have permitting authority, the new rules add another layer of regulatory hurdles by EPA. The new regulations also force a more significant overlap of the air permitting and solid waste rules. As a result, implementing an alternate material program and seeking approval has the potential to be considerably more challenging for the regulated community, in addition to adding complexity for the state agency permitting staff. This paper provides an update on the latest solid waste and air regulations applicable to alternative material use in cement plants, and potential implications for the U.S. industry. Early experiences will be explored, in addition to contemplating potential permitting and/or approval pathways expected to be encountered with the newest regulations in place. [ABSTRACT FROM AUTHOR]

To deal with the deregulated challenges in future power system operations, Taiwan Power Company (Taipower) has taken a strategic approach to implement an extensive Distribution Automation (DA) project including feeder automation (FA), trouble call management, load management, and remote metering functions in its Tai-Chung District. The project was completed in December 2002. For future extension purposes, Taipower tries to develop a comprehensive generalized step-by-step methodology for the economic evaluation of the DA project. This paper presents the methodology and results for the economic evaluation of the Tai-Chung DA project. The potential benefits of the implemented DA functions are quantified using standard mathematic formulas. An economic evaluation method using value-based analysis and present-worth analysis is performed to identify the most beneficial functions in the Taipower's implemented DA functions. Those DA functions that have great benefits should have high priority to be implemented in other distribution districts. Moreover, to find the candidate feeders for further FA extension, the sensitivity analysis of the benefit/cost ratio with respect to different customer types, feeder loads, feeder lengths, numbers of switch, and failure rates is also conducted. Accordingly, the optimum number of switch can be determined under the expected service reliability. The results and formulas obtained in this paper can also be used for return-of-investment or possible performance measure of the DA systems. [ABSTRACT FROM AUTHOR]

A significant portion of the operating cost of utilities comes from energy production. To minimize the cost, unit commitment (UC) scheduling can be used to determine the optimal commitment schedule of generation units to accommodate the forecasted demand. The load forecast is a prerequisite for UC planning. The projected load of up to seven days is important for the allocation of generation resources. Hour-ahead forecast is used for optimally dispatching online resources to supply the next hour load. This paper addresses the systematic design of a multistage artificial-neural-network-based short-term load forecaster (ANNSTLF). The developed ANNSTLF engine has been utilized in a real utility system. The performance analysis over the past year shows that a majority of the forecast error was detected in a consistent period with a large temperature forecast error. The enhancement of ANNSTLF is proposed to improve the forecasting performance. The comparison of forecasting accuracy due to this enhancement is analyzed. [ABSTRACT FROM AUTHOR]

In addition to market information, available energy and capacity to participate in the market are also essential to be an effective market participant. This paper discusses the development of an online dynamic cable rating system (DCRS) that can help a system engineer maximize asset utilization without jeopardizing system facilities or compromising the reliability of the cables. Based on real-time cable loading, cable surface temperature, ambient temperature, and forecasting temperature, the DCRS can estimate both steady-state and dynamic cable rating. To confirm with the actual operation condition, both real-time cable temperature and forecasting ambient temperature are taken into consideration to perform short-term cable ampacity estimation to prevent overestimation and/or underestimation. Based on the information provided by the DCRS, the system engineer can establish or adjust the bidding strategy in time to effectively participate in the restructured electric markets. [ABSTRACT FROM AUTHOR]

This paper presents a simplified fuzzy-logic-based speed controller of an interior permanent-magnet synchronous motor (LPMSM) drive for maximum torque per ampere (MTPA) of stator current with inherent nonlinearities of the motor. The fundamentals of fuzzy logic algorithms as related to motor control applications are illustrated. A simplified fuzzy speed controller for the LPMSM drive has been found to maintain high performance standards with a much simpler and less computation-intensive implementation than a nonsimplified fuzzy-based algorithm. Contrary to the conventional control of IPMSM with d-axis current equal to zero, a nonlinear expression of d-axis current has been derived and subsequently incorporated in the control algorithm for maximum torque operation. The efficacy of the proposed simplified fuzzy-logic-controller (FLC)-based IPMSM drive with MTPA is verified by simulation as well as experimentally at dynamic operating conditions. The simplified FLC with MTPA is found to be robust for applications in IPMSM drives. The complete vector control scheme is implemented in real-time using a digital signal processor (DSP) controller board DS 1102 in a laboratory 1-hp IPM synchronous motor. [ABSTRACT FROM AUTHOR]