Model-less/measurement-based computation of voltage sensitivities in unbalanced electrical distribution networks

Abstract

Abstract-Within the context of microgrids optimal voltage control, most schemes proposed in the literature either rely on (i) droop-control methods or (ii) methods involving the computation of explicit nodal power set-points as a solution to a given optimization problem. The first category of approaches is in general suboptimal as it relies on locally sensed measurements. The second category guarantees some level of optimality but requires an accurate and up-to-date model of the network that is, in general, not always available in low voltage grids. To overcome the aforementioned limitations, in this work we propose a methodology suitable for voltage control in generic low voltage 3-phase unbalanced grids. It can be used for the computation of either explicit power set-points or to define the droops of local voltage regulators. Its main characteristic is that it does not rely on the knowledge of the system model and its state. In particular, the goal is to compute linearized dependencies between voltage magnitude and nodal power injections, i.e., voltage sensitivity coefficients. The proposed method assumes availability of a monitoring infrastructure and the computation of the desired sensitivities involves the solution of an over-determined system of linear equations constructed solely using available measurements of nodal power injections and voltage magnitudes. The proposed method is also capable to account for the measurement errors and their time correlation. The performance evaluation of the proposed method is carried out using real measurements coming from a real low voltage feeder located in Switzerland equipped with an appropriate metering infrastructure.

Modeling and analysis: power injection model approach for high performance of electrical distribution networks

“…The various arrangements of grid-associated PV networks and power inverter geographies are portrayed as demonstrated in Figure 1. A few arrangements are proposed to control the infused power into the organization and the useful designs of every setup [6].…”

Augmented Sensitivity Estimation Based Voltage Control Strategy of Active Distribution Networks With PMU Measurement

“…Accurate model parameters are required for the modelbased methods above. However, it is difficult to ensure the parameter accuracy in the geographic information system (GIS) of distribution network [24], [25]. In this context, the data-driven method is considered in [26].…”

“…The actual reactive power of DG and SVC dispatched are also constrained by their own capacities as (24) and 25, respectively. Q DG j and Q SVC j are larger than 0 when output reactive power and less than 0 when absorb reactive power.…”

A rational decentralized generalized Nash equilibrium seeking for energy markets

“…Here the affine coupling constraints encode grid constraints, limiting voltage and power in a subset of selected nodes of the grid in which the agents are located. This is possible taking into account the linearized formulation of the power flow equations [1], [18], whose coefficients can be estimated using phasor measurement units [19], even using smart meter data [20]. The advantage of considering coupling constraints instead of agent-level constraints on voltage and power is given by the fact that the first approach can reach better solutions in terms of total welfare.…”