A new method of calculating generation linear distribution factors by least square fitting

In the security constrained dispatch, congestion management, etc, the computation of line flows is important work. It is not only necessary to meet the need of real-time, but also to guarantee the accuracy. This paper, basing on the observation of a lot of line flow data, deduces the linear relationship between generation and its active power components on transmission lines. In order to prove this deduction, some reasonable assumptions will be introduced based on the circuit theory. Using the least square fitting technique, the linear distribution factors could be obtained. When the generations have been changed, the distribution of their components and the line flows can be calculated rapidly by using these linear factors, not running the complete load flow program. Comparing with the AC or DC sensitivity methods, such as generation shift distribution fcators (GSDF) and Jacobian based distribution factors (JBDF), this method does not rely on the slack bus and its accuracy is verified by calculating IEEE9-Bus system.