A simple method of solving the controlled load flow problem of a power system in the presence of UPFC

摘要

The unified power flow controller (UPFC) has the capability of controlling the steady state power flow of a particular branch in a transmission network. This paper proposes a simple method of solving the controlled load flow problem of a power system in the presence of UPFC. First, a new static model of the UPFC is proposed to control the power flow. Some standard load flow programs are then carefully modified to incorporate the effects of the proposed UPFC model without practically changing the basic computational algorithm of the program. During the iteration process, the computed bus voltages are used to modify the control parameters of the UPFC in such a way that the functionally dependent line power flow can be kept at the desired or specified value. The effectiveness of the proposed method is then demonstrated on a power system by solving a number of controlled load flow problems. It has been found that the proposed method is very efficient and reliable.