Available Transfer Capability Determination Incorporating Reactive Power Flows and Network Uncertainties under a Deregulated Environment

Abstract

As deregulation unfolds and privatization of the power sector takes shape, a host of new technical challenges is generated to market participants and power system researchers. One of the key concepts is to quantify the remaining transfer capability in the supply system for further transactions, which is termed “available transfer capability.” Generally, in available transfer capability determination using linear sensitivity factors, such as power transfer distribution factors, the effect of reactive power flow in lines is neglected. This leads to a number of potential errors in available transfer capability calculation, and accuracy is very much affected. The main contribution of this article is to describe a simple, fast, and non-iterative method that incorporates the effect of reactive power flow directly in available transfer capability determination. A new set of distribution factors, namely the apparent power transfer distribution factor for base-case operation and the line outage apparent power transfer distribution factor for contingency-case operation, has been introduced. Since the capability of a system is highly affected by network uncertainties, single-area available transfer capability and multi-area available transfer capability are estimated for the system uncertainties using the above factors. The validity of the proposed method has been tested on IEEE 30-bus system and a practical Indian utility 69-bus system. The accuracy of the proposed method is analyzed by comparing with Newton–Raphson load flow program results.

Keywords:

• deregulation
• available transfer capability
• power transfer distribution factors
• apparent power transfer distribution factors
• multi-area available transfer capability
• sensitivity analysis