Investigation of distribution factors for bilateral contract assessment

• Published in: Electric power systems research 2003-09, Vol.66 (3), p.205-214
• Main Authors: Manjure, Durgesh P., Makram, Elham B.
• Format: Article
• Language: English
• Subjects: Bilateral contracts; Deregulation; Distribution factors
• ISSN: 0378-7796; 1873-2046
• DOI: 10.1016/S0378-7796(03)00049-X

In deregulated power systems, several market models are prevalent as alternatives to the traditional vertically integrated utilities. Consequently transmission networks are subjected to various bilateral service contracts between customers and suppliers. These transactions adversely affect power system security, and are thus executed only as far as the system design and operating conditions permit. Therefore, fast assessment of the impact of such transactions is one of the prime responsibilities of any system operator. This paper presents a scheme for comprehensive assessment of the impact of multiple, simultaneous bilateral transactions on the operating state of the transmission network. It employs improved distribution factors derived from the base case Jacobian matrix, for computation of voltage and real power flow (and real power loss). Results are presented for three standard test systems, and a comparison with the AC load flow results (and results obtained using DC power flow based distribution factors) shows that the method is fairly accurate. The paper is organized in the particular context of bilateral transactions, but possible applications of the proposed approach are also enumerated.