Control approach of three‐phase grid connected PV inverters for voltage unbalance mitigation in low‐voltage distribution grids

El-Naggar, Ahmed; Erlich, I.

doi:10.1049/iet-rpg.2016.0200

Cited by 41 publications

(42 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, accurate knowledge of r l and L l is not essential since an estimation of the term r l L l is enough. Through Equations (29) and (30), the required negative sequence reference powers to eliminate the PCC negative sequence voltage are acquired. As it is obvious from (29) and (30), considering initially a balanced system, as long as there is no negative sequence voltage at the PCC (balanced system), Q − set = P − set = 0 and thus the inverter injects only positive sequence power.…”

Section: Fault-ride-through Operationmentioning

confidence: 99%

“…Through Equations (29) and (30), the required negative sequence reference powers to eliminate the PCC negative sequence voltage are acquired. As it is obvious from (29) and (30), considering initially a balanced system, as long as there is no negative sequence voltage at the PCC (balanced system), Q − set = P − set = 0 and thus the inverter injects only positive sequence power. Note that a superiority of the proposed controller compared to existing approaches, is that when the capacity is not enough to track P − set and Q − set , priority is given to the current limitation property proven in Section 3.4, without switching to different control dynamics or suffering from integrator wind-up issues.…”

Section: Fault-ride-through Operationmentioning

confidence: 99%

See 1 more Smart Citation

Voltage Support under Grid Faults with Inherent Current Limitation for Three-Phase Droop-Controlled Inverters

Paspatis

Konstantopoulos

2019

Energies

View full text Add to dashboard Cite

A novel nonlinear current-limiting controller for three-phase grid-tied droop-controlled inverters that is capable of offering voltage support during balanced and unbalanced grid voltage drops is proposed in this paper. The proposed controller introduces a unified structure under both normal and abnormal grid conditions operating as a droop controller or following the recent fault-ride-through requirement to provide voltage support. In the case of unbalanced faults, the inverter can further inject or absorb the required negative sequence real and reactive power to eliminate the negative sequence voltage at the point of common coupling (PCC) whilst ensuring at all times boundedness for the grid current. To accomplish this task, a novel and easily implementable method for dividing the available current into the two sequences (positive and negative) is proposed, suitably adapting the proposed controller parameters. Furthermore, nonlinear input-to-state stability theory is used to guarantee that the total grid current remains limited below its given maximum value under both normal and abnormal grid conditions. Asymptotic stability for any equilibrium point of the closed-loop system in the bounded operating range is also analytically proven for first time using interconnected-systems stability analysis irrespective of the system parameters. The proposed control concept is verified using an OPAL-RT real-time digital simulation system for a three-phase inverter connected to the grid.

show abstract

Section: Fault-ride-through Operationmentioning

confidence: 99%

Section: Fault-ride-through Operationmentioning

confidence: 99%

Voltage Support under Grid Faults with Inherent Current Limitation for Three-Phase Droop-Controlled Inverters

Paspatis

Konstantopoulos

2019

Energies

View full text Add to dashboard Cite

show abstract

“…(5). Since the inverter has three-wire, there is a voltage difference (vn0) between neutral point of the grid and negative point of the DC-link.…”

Section: A) Modeling Of Systemmentioning

confidence: 99%

“…Moreover, it explains the synchronization method for grid-connected power inverters. [5]. Energy transfer from renewable energy sources to the grid is realized with power electronic converters.…”

Section: Introductionmentioning

confidence: 99%

Three phase voltage source inverters with grid connected industrial application

Prakash

Balaji

2018

IJET

View full text Add to dashboard Cite

The grid-connected issue is one of the major problems in the field of Power Electronics. In this paper, the Three Phase Voltage Source Inverter (VSI) is controlled by a Space Vector Pulse Width Modulation (SVPWM) Technique. SVPWM control technique and Park transformation, the managed inverter control system to convert input DC power into AC power, stabilize the output voltage and current, and feeds the excess power to the utility grid can be achieved by controllers. Usually, the grid source contains higher level of harmonics. To analyze the harmonics, nonlinear load is connected externally in the point of common coupling. The main aim of this paper is to modeling, simulation and experimental study of the three-phase grid connected inverter. By using the control algorithm, the grid sides Total Harmonics Distortion (THD) are controlled to the 1.54% for 800V DC as per the IEEE standard. The stimulation results such as AC output voltage and current, inverter system power flow, and grid disturbances detection signals, proves the effectiveness of the developed control algorithm. The control algorithms to makes the for this inverter outputs is pure sinusoidal.

show abstract

“…Four control schemes against voltage unbalance were also simulated. A new proposed controller was proposed in [18] to mitigate the voltage unbalance. The new controller utilized the conjugate phase angle of the positive sequence voltage for controller alignment.…”

Section: Introductionmentioning

confidence: 99%

System Unbalance Analyses and Improvement for Rooftop Photovoltaic Generation Systems in Distribution Networks

Leou

Teng

et al. 2020

Energies

View full text Add to dashboard Cite

This paper studies the system unbalance caused by rooftop Photovoltaic Generation Systems (PVGSs) in distribution networks and proposes an improved method. The voltage and current unbalance studies for three extreme cases considering all rooftop PVGSs being connected to one single phase and then the stochastic analyses for the integration cases of rooftop PVGSs are considered. These three extreme cases lead to severe system unbalance problems. An improving method that combines the On Load Tap Changer (OLTC) and the optimal phase arrangement of distribution transformers is proposed in this paper to mitigate the system unbalance. The OLTC-based improving method is applied first. If the system unbalance is still out of range, the optimal phase arrangement of distribution transformers is further used to mitigate the system unbalance problem. The objective function of optimal phase arrangement is to minimize the system unbalance with the constraints of voltage limits, line flow limit, etc. Test results show that the proposed method can improve the system unbalance significantly even under very extreme cases.

show abstract

Control approach of three‐phase grid connected PV inverters for voltage unbalance mitigation in low‐voltage distribution grids

Cited by 41 publications

References 29 publications

Voltage Support under Grid Faults with Inherent Current Limitation for Three-Phase Droop-Controlled Inverters

Voltage Support under Grid Faults with Inherent Current Limitation for Three-Phase Droop-Controlled Inverters

Three phase voltage source inverters with grid connected industrial application

System Unbalance Analyses and Improvement for Rooftop Photovoltaic Generation Systems in Distribution Networks

Contact Info

Product

Resources

About