Fast Decoupled State Estimation for Distribution Networks Considering Branch Ampere Measurements

Abstract

Fast decoupled state estimation (FDSE) is proposed for distribution networks, with fast convergence and high efficiency. Conventionally, branch current magnitude measurements cannot be incorporated into FDSE models; however, in this paper, branch ampere measurements are reformulated as active and reactive branch loss measurements and directly formulated in the proposed FDSE model. Using the complex per unit normalization technique and special chosen state variables, the performance of this FDSE can be guaranteed when it is applied to distribution networks. Numerical tests on seven different distribution networks show that this method outperforms Newton type solutions and is a promising method for practical application.

Voltage Estimation Method for Power Distribution Networks Using High-Precision Measurements

“…Taking into consideration the narrow voltage regulation range, it is crucial to accurately measure the line voltages for efficient and reliable control. Most WLS-based SE assume that loads are concentered on nodes and the magnitudes of loads are known [9][10][11][12]. However, the actual loads are not concentered on nodes but distributed in sections.…”

“…where , is the initial section load center between node n and n + 1. is the + of the node n, and ST denotes each section type. In Equation (8), the constant term except on the right side is equal to the initial voltage estimate of the node m. Accordingly, if all the values except are put from the right side to the left side, an estimation error is obtained, as expressed in Equation (9). If Equation 9is arranged with respect to α , the section load center can be expressed by using Equation (10).…”

A Fully Distributed Coordination Method for Fast Decoupled Multi-Region State Estimation

“…Accurate state estimation (SE) of interconnected power systems is critical for assessing system security and optimizing performances. [1], [2]. This becomes particularly challenging for continental-scale power systems that rely on the coordination of multiple dispatch centers, while each one of the dispatch centers controls a large-scale region.…”

Generalised‐fast decoupled state estimator

“…In [26], a new FDSE is presented by the rotation transformation, this method is suitable for networks with a high ratio of R / X , but the rotation transformation will greatly reduce the accuracy and efficiency of calculation, and rotated measurements do not include BCMMs still. Recently, a new FDSE for distribution systems is proposed in [27], the advantage of this method is that BCMMs can be used in FDSE by approximately reformulating BCMMs as active and reactive branch loss measurements; the drawback is that the computational efficiency has been affected by additional state variables, and the applicability of this approach to distribution systems with high ratio of R / X has not been discussed.…”