Voltage Control in Smart Grids: An Approach Based on Sensitivity Theory

Abstract

Due to the development of Distributed Generation (DG), which is installed in Medium-Voltage Distribution Networks (MVDNs) such as generators based on renewable energy (e.g., wind energy or solar energy), voltage control is currently a very important issue. The voltage is now regulated at the MV busbars acting on the On-Load Tap Changer of the HV/MV transformer. This method does not guarantee the correct voltage value in the network nodes when the distributed generators deliver their power. In this paper an approach based on Sensitivity Theory is shown, in order to control the node voltages regulating the reactive power exchanged between the network and the dispersed generators. The automatic distributed voltage regulation is a particular topic of the Smart Grids

Sensitivity and functionally oriented models for power system planning, operation, and control

“…; J. As it was indicated above, the construction of sensitivities in [2][3][4][5][6][7][8][9][10][11][12][13][14] is based on the use of system Jacobian matrices and encounters limitations. At the same time, the application of experimental design [16][17][18] provides a means for building adequate sensitivity models.…”

“…as the reproducibility dispersion which can be used to test the significance of coefficients of the constructed models and their adequacy on the basis of the Student's test (9) and the Fisher's test (10), respectively.…”

“…As an example, it is possible to indicate the problem of voltage and reactive power control in power systems. The techniques for its solution related to applying optimization as well as knowledge based approaches (for instance, [2][3][4][5][6][7][8][9][10][11][12][13][14]) utilize diverse algorithmic modifications of the method [15] allowing the use of the system Jacobian matrices to build sensitivities (by the way, the solution of other power engineering problems with the use of sensitivity models is also based on applying techniques associated with utilizing Jacobian matrices [2]). However, deficient linearization accuracy permits one to use these techniques when perturbations are small (for example, discussion to [3]).…”

Fast Probabilistic Voltage Control for Distribution Networks With Distributed Generation Using Polynomial Surrogates

“…However, a linear approximation may not be accurate when large changes in power generation or consumption are considered. In [15], an analytical approach for sensitivity analysis was proposed, but several simplifying assumptions (e.g., considering the power losses to be negligible) were made which can compromise accuracy. In [13], a surface-fitting approach was used to approximate voltage, but it required an unnecessarily large number of simulations.…”

Improving voltage control in MV smart grids

“…One classical control makes use of On Load Tap Changer (OLTC) [3]. Another approach exploits control of the active power or reactive power injected by distributed generators [4]. [5] presents an MPC-based algorithm to act on both OLTC and distributed generators.…”