scholarly journals Photovoltaic Inverter Profiles in Relation to the European Network Code NC RfG and the Requirements of Polish Distribution System Operators

Energies ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1486
Author(s):  
Krzysztof Chmielowiec ◽  
Łukasz Topolski ◽  
Aleks Piszczek ◽  
Zbigniew Hanzelka
Keyword(s):  
Distribution System ◽  
Reactive Power ◽  
Low Voltage ◽  
Network Code ◽  
Electrical Networks ◽  
Pv Inverter ◽  
Technical Requirements ◽  
Eu Energy Policy ◽  
Support Programmes ◽  
The Eu

The presently observed rapid increase in photovoltaic (PV) micro-installation connections to low-voltage networks, resulting from numerous financial support programmes, European Union (EU) energy policy and growing social awareness of environmental and economic issues, raise the question if PV inverters widely available in EU market fulfil the numerous technical requirements specified in European and Polish regulations. The paper presents the results of an experimental study carried out on three PV Inverters widely available in the EU in accordance with the EU network code NC RfG, standard EN 50549-1:2019 and internal Polish distribution system operators’ (DSOs’) regulations, governing PV inverter cooperation with the low-voltage distribution network. The laboratory test stand scheme and its description are presented. In each test, at least one of the inverters encountered issues, either with the operation in required frequency ranges (one PV inverter), activating reactive power control modes (all three PV inverters), maintaining required power generation gradient after tripping (one PV inverter) or under-voltage ride through immunity (one PV inverter). The obtained results have shown that all tested PV inverters did not meet requirements that are the key to maintaining reliable and safe operation of transmission and distribution electrical networks.

Control Strategy of Low Voltage Ride-Through for Grid-Connected Photovoltaic Power System Based on Predictive Current

2014 ◽  
Vol 556-562 ◽  
pp. 1753-1756
Author(s):  
Ming Guang Zhang ◽  
Xiao Jing Chen
Keyword(s):  
Control Strategy ◽  
Reactive Power ◽  
Low Voltage ◽  
Photovoltaic System ◽  
Stable Operation ◽  
Voltage Sags ◽  
Low Voltage Ride Through ◽  
Pv Inverter ◽  
Current Instruction ◽  
Voltage Recovery

The control strategy based on predictive current is proposed to solve problems that destruct stable operation of grid-connected photovoltaic system during asymmetrical fall. A mathematical model of PV inverter is established to calculate current instruction; a method of tracking based on predictive current is proposed to reduce the fluctuations of 2 times frequency. In the meantime, PV inverter provides reactive power to support voltage recovery according to the depth of grid voltage sags and realize LVRT. The result also shows that the proposed control strategy can reduce wave of DC voltage and provide reactive power to support voltage recovery.

scholarly journals DFIG use with combined strategy in case of failure of wind farm

2020 ◽  
Vol 10 (3) ◽  
pp. 2221
Author(s):  
Azeddine Loulijat ◽  
Najib Ababssi ◽  
Mohammed Makhad
Keyword(s):  
Wind Power ◽  
Wind Turbines ◽  
Wind Farm ◽  
Reactive Power ◽  
Low Voltage ◽  
Voltage Drop ◽  
Optimal Solution ◽  
Wind Farms ◽  
Electrical Networks ◽  
Constant Frequency

In the wind power area, Doubly Fed Induction Generator (DFIG) has many advantages due to its ability to provide power to voltage and constant frequency during rotor speed changes, which provides better wind capture as compared to fixed speed wind turbines (WTs). The high sensitivity of the DFIG towards electrical faults brings up many challenges in terms of compliance with requirements imposed by the operators of electrical networks. Indeed, in case of a fault in the network, wind power stations are switched off automatically to avoid damage in wind turbines, but now the network connection requirements impose stricter regulations on wind farms in particular in terms of Low Voltage Ride through (LVRT), and network support capabilities. In order to comply with these codes, it is crucial for wind turbines to redesign advanced control, for which wind turbines must, when detecting an abnormal voltage, stay connected to provide reactive power ensuring a safe and reliable operation of the network during and after the fault. The objective of this work is to offer solutions that enable wind turbines remain connected generators, after such a significant voltage drop. We managed to make an improvement of classical control, whose effectiveness has been verified for low voltage dips. For voltage descents, we proposed protection devices as the Stator Damping Resistance (SDR) and the CROWBAR. Finally, we developed a strategy of combining the solutions, and depending on the depth of the sag, the choice of the optimal solution is performed.

scholarly journals Improving voltage profile of load bus of wind generation system using DSTATCOM

2017 ◽  
Vol 26 (4) ◽  
pp. 81
Author(s):  
Manju Aggarwal ◽  
Madhusudan Singh ◽  
S.K. Gupta
Keyword(s):  
Distribution System ◽  
Voltage Stability ◽  
Reactive Power ◽  
Low Voltage ◽  
Stability Margin ◽  
Wind Generation ◽  
Voltage Profile ◽  
Generation System ◽  
Wind Generation System ◽  
The Impact

In a low voltage distribution system with integrated wind plant, voltage stability is impacted by the large variation of load and wind penetration. The compensators like SVC and DSTATCOM are currently being used to address such issue of voltage instability. This paper analyses the impact of wind penetration and variation of active and reactive power of the load on voltage profile of a wind generation system with and without DSTATCOM. It also analyses the performance of the system during fault by calculating various parameters of the system. It has been demonstrated that voltage stability margin increases using DSTATCOM at different wind penetration levels. This system has been simulated and analysed in MATLAB 2011b using a power system toolbox under steady state and transient conditions.

scholarly journals Decentralized Control of PV Inverter to Mitigate Voltage Rise in Resistive Feeder

2018 ◽  
Vol 69 ◽  
pp. 01009
Author(s):  
Tzung-Lin Lee ◽  
Shang-Hung Hu ◽  
Shih-Sian Yang
Keyword(s):  
Decentralized Control ◽  
Reactive Power ◽  
Low Voltage ◽  
Voltage Measurement ◽  
Maximum Power Point ◽  
Voltage Rise ◽  
Point Tracking ◽  
Pv Inverter ◽  
Power Point Tracking ◽  
Power Point

Increasing installation of photovoltaic (PV) in the distribution power system has resulted in serious voltage rise, limiting grid-connectable power. This scenario becomes significant in the low-voltage resistive feeder. This paper proposes a decentralized control for distributed PV inverters to mitigate voltage rise. Instead of MPPT (maximum power point tracking) mode, the proposed PV inverter is able to curtail its real power and compensate the reactive power according to the impedance at the installation location. The drooped characteristics between the output power and the impedance are developed so that the PV inverters are able to cooperatively suppress voltage rise based on their local voltage measurement only. Therefore, PV inverters are allowed to supply more power to the utility within voltage limitation. Simulations are conducted to guarantee the proposed control on improvement of voltage rise considering different parameter of feeder. A lab-scaled prototype circuit is established to verify effectiveness in a resistive feeder.

scholarly journals Energy Loss Minimization by Optimal Siting and Sizing of DG with Network Reconfiguration in Distribution Networks

2019 ◽  
Vol 8 (10) ◽  
pp. 3621-3625
Keyword(s):  
Energy Loss ◽  
Distribution System ◽  
Power Loss ◽  
Reactive Power ◽  
Low Voltage ◽  
Distribution Networks ◽  
Network Reconfiguration ◽  
Voltage Profile ◽  
Loss Minimization ◽  
Power Loss Reduction

The main aim of the distribution system is delivery the power to the consumers. Because of, aging of electrical infrastructure, old control mechanism, increased power demand causing exploitation of the present electrical networks leads to low voltage profile, more active and reactive power loss with various power quality related issues causing poor network operation. In this method maximization of voltage profile with energy loss minimization is carried using network reconfiguration along with optimal siting of the distributed generation (DG). The proposed methodology is carried out on five bus system. The obtained results are impressive interms of voltage stability and power loss reduction.

A Key Strategy for Controlling the High-Power Photovoltaic Inverter

2014 ◽  
Vol 577 ◽  
pp. 463-468
Author(s):  
Jing Hua Zhou ◽  
An Wei Cui ◽  
Xiao Wei Zhang
Keyword(s):  
High Power ◽  
Control Strategy ◽  
Reactive Power ◽  
Low Voltage ◽  
Variable Step Size ◽  
Islanding Detection ◽  
Power Prediction ◽  
Step Size ◽  
Point Tracking ◽  
Pv Inverter

In this paper, a systematic control strategy has been proposed for specific problems with the various key performance indicators of the high-power photovoltaic (PV) inverter when it connects to the grid. it proposes fast and accurate variable-step-size perturbation and observation combined with power prediction as a Maximum Power Point Tracking-based (MPPT) control strategy. To meet the requirements for low voltage ride through (LVRT), it proposes a strategy for LVRT control. It adopts an active method used for anti-islanding detection of reactive power disturbance so as to realize anti-islanding detection quickly. Finally, it carries out testing on the control strategy by means of an experimental platform with a 500 kW PV inverter to prove the effectiveness of the proposed control strategy.

Sign in / Sign up

Export Citation Format

Share Document