New Requirements of the Voltage/VAR Function for Smart Inverter in Distributed Generation Control

Abstract

International Electronical Committee (IEC) 61850-90-7 is a part of the IEC 61850 series which specifies the advanced functions and object models for power converter based Distributed Energy Resources (DERs). One of its functions, the Voltage/VAR (V/V) control function, is used to enhance the stability and the reliability of the voltage in the distribution system. The conventional V/V function acts mainly for flattening the voltage profile as for a basic grid support function. Currently, other objectives such as the minimization of line loss and the operational costs reduction are coming into the spotlight. In order to attain these objectives, the V/V function and hence the DER units shall actively respond to the change of distribution system conditions. In this paper, the modification of V/V function and new requirements are proposed. To derive new requirements of V/V function, loss minimization is applied to a particle swarm optimization (PSO) algorithm where the condition of voltage constraint is considered not to deteriorate the voltage stability of the distribution system.

Reactive Power Management Based on Voltage Sensitivity Analysis of Distribution System with High Penetration of Renewable Energies

“…∆Q s1 DG and ∆Q s2 DG are the reactive power generation of buses, to which DERs are connected, before and after the DERs disconnection, respectively. Consequently, from Equations (3), (9), and (11), the reactive power compensation, ∆Q s1…”

“…Many reactive power control methods for DERs to mitigate the voltage variation have been reported in the literature. The Q(V) droop control has been widely used for the reactive power management of DERs [6][7][8][9]. This method is characterized in that the required reactive power is determined by the voltage state at the point of common coupling (PCC).…”

“…Presently, the Q(V) droop control is further advanced with the advent of smart inverter (SI). Then, the SI function for Q(V) droop control is proposed in [9] to minimize the loss of system while optimizing the slope of Q(V) curve with the objective function of loss. However, when the weather conditions change rapidly, the conventional droop control cannot deal with the system changes [10].…”

Adaptive Volt-VAr Control Algorithm to Grid Strength and PV Inverter Characteristics

“…However, in our study, a RTU is installed close to the PCC obtaining local measurements and providing the parameters that define the Volt-VAr control to each PV inverter; this versatile equipment gives a clear advantage in front of what is exposed. Meanwhile in [14] new requirements for Volt-VAr control functions are highlighted, such as the minimization of line losses, in our study this requirement is included and extended with an algorithm design that is able to adapt the control parameters to the grid topology changes. Its unique feature makes this algorithm valuable since it is a global solution for both weak and strong grids.…”

Coordinated control of multifunctional inverters for voltage support and harmonic compensation in a grid-connected microgrid

“…According to this standard, the DG units shall respond to the voltage variation in order to enhance the voltage profile of power system [30]. According to the standard and the method presented in [3], the reactive power compensation is implemented in this paper.…”