Voltage control in low voltage grids: A comparison between the use of distributed photovoltaic converters or centralized devices

Abstract

In this paper, three solutions for the control of voltage in Low Voltage (LV) grids with high photovoltaic (PV) penetration are simulated and compared. The first solution corresponds to the use of distributed PV converters to control voltage in their connection points. In other cases, a centralized control is performed, by using a Static Var Compensator or a transformer with On Load Tap Changer installed inside the MV/LV substation. Benefits on voltage profiles and reduction of losses are shown through simulations carried out on a real grid. The consumption and PV generation profiles come from accurate measurements performed in apartment and office buildings with 1-second time step.

Voltage Control in Low-Voltage Grids Using Distributed Photovoltaic Converters and Centralized Devices

“…In [15], it was proposed a procedure essentially based on the satisfaction of the Standard [5], for what concerns the voltage ranges in which converters have to use reactive power. In this paper, a double-band hysteresis control (DBHC) is studied: its limits are varied, in order to find the most suitable setup of the converters to regulate the voltage.…”

“…Then, the maximum level of reactive power Q max,n (t) that the PV system installed in node n can provide is calculated (STEP#3). According to the Standard [5], a triangular capability curve is respected, so that the power factor (PF) never decreases below the limit PF min = 0.9, as described in [15]. Then, in STEP#4, the needed amount of reactive power to control voltage is calculated by an algorithm based on the P&O technique.…”

“…These aspects have been addressed in [14], where voltage profiles and losses obtained by controlling voltage with these centralized solutions are compared with another case study, in which distributed PV inverters manage reactive power to adjust voltage in their connection points (CPs). This paper is the extended version of [15], in which the effect of voltage control performed by the combination of the above described centralized and distributed solutions is analyzed.…”

An integrated testbed for locally monitoring SCADA systems in smart grids

“…In the past, the monitoring using SCADA systems was mainly used in transmission of the electricity operating at High Voltage. However, due to increased use of DERs such as PV panels, there is an increased need for implementing such control and monitoring also at Low and Medium Voltage (Lu et al 2015;Ciocia et al 2017;Bell et al 2018).…”

A Smart Battery Management System for Photovoltaic Plants in Households Based on Raw Production Forecast

“…At distribution system level, the large share of RES led researcher to consider new way to manage the system, by means of optimal reconfiguration procedure based on different methodology [3] and time periods [4]. The main drawback of RES is the intermittency of power production, which often results in a not well match between electric consumption and generation profiles [5,6], with consequent voltage deviations and reverse power flow issues [7]. In order to reduce voltage deviations, it is possible to upgrade grid lines and transformers, but it is generally expensive.…”