Estimation and Allocation of Reactive Power Loss in Interconnected Power Systems Through Network Structural Characteristics Theory

Abstract

The mathematical formulations for estimating and allocating reactive power loss to network participants are highly nonlinear and mathematically complex. Consequently, the well-known solution based on traditional techniques could only be obtained through iterative procedures. An alternative computational algorithm based on network structural characteristics theory (NSCT), which provides an efficient solution to estimation of reactive power loss contributions from various network sources and the allocation of the estimated losses in pool-based markets, is proposed in this paper. The theoretical background and mathematical formulations of the approach, which solely based on basic circuit theory laws, are presented. From the first principle, the problem is formulated as a linear combination of the network parameters, which eliminates the challenges encountered in the traditional iterative-based approaches. Based on NSCT, a constant coefficient matrix termed Network Structure Coefficient Matrix (NSCM) is then introduced. The reactive power loss contributions, by each source toward individual sink, are then determined based on the NSCM developed. Total reactive power loss for the network based on the developed NSCM is also estimated. The effectiveness of the technique is verified using a simple 3-bus system, a 5-bus network and the standard IEEE 57-bus network. The results obtained using various traditional AC power-flow-based methods and that of the proposed approach are compared. The comparison of results clearly demonstrated that the efficient solution to reactive power loss estimation and allocation can be easily obtained based on the topological properties of the network without carrying out the repetitive and time-consuming power-flow analysis.