CPFLOW: a practical tool for tracing power system steady-state stationary behavior due to load and generation variations

In this paper, a computer package called CPFLOW, which is a comprehensive tool for tracing power system steady-state stationary behavior due to parameter variations, is presented. The variations include general bus real and/or reactive loads, area real and/or reactive loads, or system-wide real and/or reactive loads, and real generation at P-V buses (e.g. determined by economic dispatch or participation factor). The main advantages of CPFLOW over repetitive power flow calculations are its computational speed and reliability as well as its wide applicability. A detailed description of the implementation regarding the predictor, corrector, step-size control and parameterizations employed in CPFLOW is presented. CPFLOW has comprehensive modeling capability and can handle power systems up to 12000 buses. For an illustrative purpose, CPFLOW is applied to a 3500-bus power system with a comprehensive set of operational limits and controls