• The Transactions of the Korean Institute of Electrical Engineers A
• /
• v.51 no.12
• /
• pp.603-610
• /
• 2002

In this paper, a new economic dispatch algorithm for unit commitment is proposed to improve both the accuracy of the final solution and the calculation speed of economic dispatch. By using the inverse incremental cost functions, economic dispatch can be transformed into a simple optimization problem associated with an n-th order polynomial equation. The proposed method remarkably reduces the computation time with adaptability to any higher order generation cost functions. The proposed method is tested with sample system, which shows that the proposed algorithm yields more accurate and economical generation scheduling results with high computation speed.

• The Transactions of the Korean Institute of Electrical Engineers A
• /
• v.54 no.3
• /
• pp.152-157
• /
• 2005

An objected-oriented programming(OOP) technique is introduced to dispatch schedules for TWBP. Some dispatch schedules such as constrained (pre)dispatch, unconstrained (pre)dispatch, and nominal self-dispatch schedule need to be peformed to make power market work. These dispatch schedules are similar but have some differences in required constraints, needed data, and scheduling time. Therefore, it makes the scheduling program simple to introduce the OOP technique to this problem: to have each instance of the OOP perform its own dispatch scheduling. The developed program adopts linear programming(LP) as an optimization tool and could consider some crucial constraints such as power balance, generation power limits, generation ramp-rates, power limitations of transmission lines, and power system security.

• Proceedings of the KIEE Conference
• /
• 2000.07a
• /
• pp.347-349
• /
• 2000

Under an open transmission access, the generation dispatch is determined by the bidding process of market participants. Congestion occurs when the dispatch would result in the violation of operational constraints. Congestion problem is formulated and solved by OPF(optimal power flow) calculation. The objective functions in OPF are given as quadratic cost functions or piecewise linear functions of bidding functions. In this study, the optimization technique of generation dispatch is presented for the combination of two types of quadratic and linear cost functions.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.17 no.4
• /
• pp.219-224
• /
• 2017

In facing the lack of a deterministic algorithm for economic load dispatch optimization problem, only non-deterministic heuristic algorithms have been suggested. Worse still, there is a near deficiency of research devoted to real-time load dispatch optimization algorithm. In this paper, therefore, I devise a shut-off and swap algorithm to solve real-time load dispatch optimization problem. With this algorithm in place, generators with maximum cost-per-unit generation power are to be shut off. The proposed shut-off criteria use only quadratic function in power generation cost function without valve effect nonlinear absolute function. When applied to the most prevalent economic load dispatch benchmark data, the proposed algorithm is proven to largely reduce the power cost of known algorithms.

• The Transactions of the Korean Institute of Electrical Engineers A
• /
• v.50 no.9
• /
• pp.424-430
• /
• 2001

A multi-level optimal power flow(OPF) algorithm has been evolved from a simple two stage optimal Power flow algorithm for constrained power economic dispatch control. In the proposed algorithm, we consider various constraints such as ower balance, generation capacity, transmission line capacity, transmission losses, security equality, and security inequality constraints. The proposed algorithm consists of four stages. At the first stage, we solve the aggregated problem that is the crude classical economic dispatch problem without considering transmission losses. An initial solution is obtained by the aggregation concept in which the solution satisfies the power balance equations and generation capacity constraints. Then, after load flow analysis, the transmission losses of an initial generation setting are matched by the slack bus generator that produces power with the cheapest cost. At the second stage we consider transmission losses. Formulation of the second stage becomes classical economic dispatch problem involving the transmission losses, which are distributed to all generators. Once a feasible solution is obtained from the second stage, transmission capacity and other violations are checked and corrected locally and quickly at the third stage. The fourth stage fine tunes the solution of the third stage to reach a real minimum. The proposed approach speeds up the two stage optimization method to an average gain of 2.99 for IEEE 30, 57, and 118 bus systems and EPRI Scenario systems A through D testings.

• The Transactions of the Korean Institute of Electrical Engineers A
• /
• v.54 no.12
• /
• pp.586-591
• /
• 2005

This paper presents a method of minimizing of generation cost on individual electrical power utility. The method is based on the Economic Dispatch (ED) and linear Available Transfer Capability (ATC). The economic dispatch redistributes the total load to individual units to minimize the generation cost without transmission network constraints. The proposed method is implemented using ATC calculated from Power Transfer Distribution Factor (PTDF) for the transmission network constraints. The performance of the proposed method has been tested for the IEEE-30 bus system. It has also been observed that the results of the proposed method is compared with that of optimal power flow.

• Proceedings of the KIEE Conference
• /
• 2000.07a
• /
• pp.391-393
• /
• 2000

This paper presents an new algorithm for the economic load dispatch considering the reliability level constraints of composite power system under deregulated electricity market. It is the traditional ELD problem that generation powers have been dispatched In order to minimize total fuel cost subjected to constraints which sum of powers generated must equal the received load and no violating lower and upper limit constraints on generation. Under deregulated electricity market, however, generation powers of a pool have to be reallocated newly in order to satisfy the reliability differentiated level required at a load point because of a reliability differentiated electricity service which is a part of the priority service. In this study, new economic load dispatch algorithm for reallocating the generation powers of a pool in order to satisfy the reliability differentiated level under deregulated competitive electricity market is proposed. The uncertainties of not only generators but also transmission lines are considered fer the reliability evaluation. The characteristics and effectiveness of this methodology are illustrated by the case studies on MRBTS and IEEE-RTS.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.16 no.2
• /
• pp.181-188
• /
• 2016

This paper demonstrates that centralized economic load dispatch optimization is much more economical than independent optimization carried out by individual power generating companies. The algorithm applied here optimizes by balancing the generation power at the valve-point, then readjusting generation power by comparing incremental operating cost incurred by marginal increase in the generation power and decremental operating cost likewise incurred by marginal decrease in the generation power. Upon comparing 3 individual optimization cases of 10, 13, and 40 generators respectively with centralized optimization of 63 generators, centralized operation for economic load dispatch optimization has proven to maximize economic benefits by markedly reducing operation costs of individual optimization.

• The Transactions of the Korean Institute of Electrical Engineers A
• /
• v.48 no.3
• /
• pp.203-211
• /
• 1999

This paper presents a new approach on genetic on genetic algorithm to economic dispatch problem for valve point discontinuities. Proposed approach in this paper on genetic algorithms improves the performance to solve economic dispatch problem for valve point discontivuities through improved death penalty method, generation-apart elitism, atavism and sexual selection with sexual distinction. Numerical results on a test system consisting of 13 thermal units show that the proposed approach is faster, more robust and powerful than conventional genetic algorithms.

• The Transactions of the Korean Institute of Electrical Engineers A
• /
• v.53 no.10
• /
• pp.573-580
• /
• 2004

A new real-time constrained dispatch scheduling (CDS) is needed for TWBP. The CDS needs to be performed at every dispatch period to decide generation power of scheduling generators and amounts of scheduling load. Therefore, the CDS is not based on real generation costs but on bidding data of market participants with some constraints such as power balance, generation limits, ancillary service, and transmission line limits. This paper selects linear programming(LP) as an optimization tool for the CDS and presents effective formulae for the LP application. This paper also presents the way of minimizing the number of variables and constraints of the LP to improve real-time applicability.