LVRT Capability Research Articles

Improve LVRT capability of organic solar arrays by using chaos-based NMPC

Electric utilities are continuously scheduling to develop power grids in order to supply the electrical energy demanded by their consumers. The common method is the construction of traditional power plants or development of existing infrastructures. The challenges associated with using fossil fuel, such as environmental pollution and climate changing like glacier melting and rising sea levels, highlight the importance of using green energy sources like photovoltaic systems. In other side, extracting the maximum power under intermittent generated power has a great importance. So, a novel chaotic-based nonlinear model predictive control method is introduced for tracking the maximum power point of organic photovoltaic cells. The proposed approach involves estimating a reference point and adjusting the operating point by using a Lagrangian function. Also, chaotic-based nonlinear model predictive controller is used for controlling the operation of boost converter. According to obtained results, the proposed approach capable of fast tracking as well as improving the ride through capacity.

Enhancing LVRT capability of single stage grid connected PV system in accordance with Indian grid code using proportional direct axis current control technique

Enhancing LVRT capability of single stage grid connected PV system in accordance with Indian grid code using proportional direct axis current control technique

Improvement of LVRT capability of grid‐connected wind‐based microgrid using a hybrid GOA‐PSO‐tuned STATCOM for adherence to grid standards

Improvement of LVRT capability of grid‐connected wind‐based microgrid using a hybrid GOA‐PSO‐tuned STATCOM for adherence to grid standards

DGFACTS comparative in wind power to solve LVRT requirements

This article compares the results recorded in the connection of three types of DGFACTS (DSTATCOM, DVR, UPQC) to a wind farm equipped with wind turbines with squirrel-cage induction generators, in order to test the response to voltage dips due to single-phase short circuit and two phase short circuit, because this type of asymmetric faults is one of the most common to consider a power system. The results are compared with a previous work, dealing with symmetric (three phase) short circuits. For illustrative purposes, reference has been made to a standard wind farm in Spain, which has been subject to a fault of the type specified in Operating Procedure 12.3 in the Spanish Grid Code. The aforementioned options provide the wind farms with LVRT capability, in addition to catering for numerous other possibilities that have not been considered within this research.

A Novel Intelligent Power Control Technique for a Type-3 Wind Energy Conversion System with LVRT Capability and Improved Dynamic Performance

A Novel Intelligent Power Control Technique for a Type-3 Wind Energy Conversion System with LVRT Capability and Improved Dynamic Performance

Enhancing Grid-Connected DFIG’s LVRT Capability Using Dandelion Optimizer Based the Hybrid Fractional-Order PI and PI Controlled STATCOM

Enhancing Grid-Connected DFIG’s LVRT Capability Using Dandelion Optimizer Based the Hybrid Fractional-Order PI and PI Controlled STATCOM

Modeling, Integration and Simulation of the Photovoltaic Power Plant Considering LVRT Capability and Transient Voltage Stability

This paper investigates how high photovoltaic energy penetration impacts dynamic performance and voltage regulation of the modified IEEE-9 bus grid. The transmission power system was modeled and simulated using PSCAD-EMTDC software to conduct the study. Load flow analysis is implemented to explore the power system’s capability to incorporate the desired photovoltaic power. Moreover, the study is based on time response simulations to grid disturbances. The supply and control of reactive power from solar power generation plants are becoming critical issues to study because they can facilitate the integration of PV in power grids under different operating conditions. Network-related faults like a PV solar power plant event outage, a three-phase short-circuit at a conventional bus, and a voltage dip at the PV solar power plant have been considered. The results will help identify the protective devices and strategies needed to maintain the stability and reliability of the system operation and transient analysis of the network under external power network fault and recovery operation. Thus, it has practical significance for real utility studies. Moreover, this comprehensive study will be a valuable guide for assessing and improving the grid’s performance under the study of any other grids, which also gives the vast potential and need for solar energy penetration into the grid systems.

A Novel Neuro-Fuzzy Based Direct Power Control of a DFIG Based Wind Farm Incorporated With Distance Protection Scheme and LVRT Capability

A Novel Neuro-Fuzzy Based Direct Power Control of a DFIG Based Wind Farm Incorporated With Distance Protection Scheme and LVRT Capability

A novel application of adaptive filtering algorithm for LVRT capability enhancement of grid-connected DFIG-based wind energy conversion systems (WECS)

A novel application of adaptive filtering algorithm for LVRT capability enhancement of grid-connected DFIG-based wind energy conversion systems (WECS)

Improvement of LVRT Capability for DFIG based WECS by Optimal Design of FoPID Controller using SLnO + GWO Algorithm

Improvement of LVRT Capability for DFIG based WECS by Optimal Design of FoPID Controller using SLnO + GWO Algorithm

Stability Enhancement of Grid-Connected Wind Power Generation System Using PSS, SFCL and STATCOM

The stability related issues may occur in a power system due to disturbances in generating or loading conditions, especially in the presence of distributed generation (DG) based on renewable energy resources (RERs). This paper proposes a novel strategy for the stability enhancement of a wind power generation system (WPGS) by using a combination of three devices, namely, a power system stabilizer (PSS), resistive superconductor fault current limiter (R-SFCL) and static synchronous compensator (STATCOM). The small signal (SS) stability of the test system is enhanced by selecting the best PSS type from the different types of PSS. An R-SFCL is used for improving the rotor angle and the frequency stability of the test system. Two indices, namely, transient stability index and sum of maximum deviations (SMD) index are introduced for determining the optimal locations of different sized R-SFCLs for increasing the rotor angle stability. The sensitivity index (SI) based on the power change between areas is applied for determining the optimal locations of different sized R-SFCLs for enhancing the frequency stability. Along with rotor angle and frequency stability, LVRT capability improvement of the wind farm using STATCOM is also considered. Finally, the combined effect of R-SFCL and STATCOM on the rotor angle and the frequency stability, for different fault locations, is also investigated for determining the optimal location of an R-SFCL in the presence of STATCOM. The results presented in the paper show that STATCOM affects both the number of feasible locations and the optimal locations that can be selected for different sized R-SFCLs for augmenting the rotor angle and the frequency stability of the system during faults. Moreover, it is pointed out that an optimal combination between the different sizes and the locations of R-SFCLs and STATCOM exists to enhance the overall stability of the test system under fault conditions.

Mountain Gazelle Algorithm-Based Optimal Control Strategy for Improving LVRT Capability of Grid-Tied Wind Power Stations

Mountain Gazelle Algorithm-Based Optimal Control Strategy for Improving LVRT Capability of Grid-Tied Wind Power Stations

Improving Transient Stability of a Synchronous Generator Using UIPC with a Unified Control Scheme

In this paper, the Unified Interphase Power Controller (UIPC) is utilized to protect the synchronous generator in case of faults occurring in the transmission system. The UIPC not only maintains the generator’s stability by keeping its load angle within safe operational limits but also prevents high-amplitude currents from flowing through the stator windings. This also allows for more loading on the generator without compromising the system’s stability. Moreover, utilization of the UIPC improves the LVRT capability of the generator by injecting reactive power at the faulted location. Additionally, a novel unified control scheme is proposed for the UIPC that enhances its performance by omitting the necessity of fault detection algorithms. To evaluate the performance of the proposed controller and the efficacy of the UIPC in protecting the synchronous generator under the faults, simulations have been conducted in a MATLAB/Simulink environment. A test grid was developed comprising a synchronous generator, transmission line model, UIPC, and an infinite grid representing the Point of Common Coupling (PCC), and three fault scenarios have been implemented in the transmission system. The comparative analysis of simulation results demonstrates the capability and efficacy of UIPC in isolating the synchronous generator from the faulted location, which in turn not only enhances transient stability of the generator, but also protects generator windings from detrimental faults currents. Moreover, according to the results, UIPC also contributes to recovering the voltage dip of the fault location via injecting reactive power.

Enhancing low voltage ride through capability of grid connected DFIG based WECS using WCA-PSO tuned STATCOM controller

This paper investigates the utilization of a STATCOM to enhance the LVRT capability of a 9 MW DFIG based Wind Power Plant (WPP) during grid faults. The STATCOM under investigation is tuned using the Water Cycle Algorithm (WCA), Particle Swarm Optimization (PSO) and a hybrid algorithm of both WCA and PSO. Simulations are carried out in MATLAB programming software, using SimScape toolbox. Performance analysis is done by investigating the ability of the test system to ride through voltage sags on the grid side, with incorporation of the STATCOM tuned using WCA, PSO and further with the hybrid WCA-PSO algorithm. To confirm effectiveness of the proposed algorithm, simulation results for the three scenarios are compared. Results show that LVRT capability of the Danish power system was met for L-G faults. However, without a STATCOM, the WPP could not ride through LLL-G faults. When STATCOM was incorporated, LVRT capability requirements were met. Voltage fluctuations reduce from 17% to 3%, without STATCOM and with WCA-PSO tuned model, respectively, during L-G faults. During LLL-G faults, voltage magnitude fluctuates from 60% to 25%, without STATCOM and with WCA-PSO tuned model respectively. WCA-PSO tuned STATCOM also resulted in the least voltage, active and reactive power overshoots.

A Comprehensive Review of LVRT Capability and Advanced Nonlinear Backstepping Control of Grid-Connected Wind-Turbine-Driven Permanent Magnet Synchronous Generator During Voltage Dips

A Comprehensive Review of LVRT Capability and Advanced Nonlinear Backstepping Control of Grid-Connected Wind-Turbine-Driven Permanent Magnet Synchronous Generator During Voltage Dips

STATCOM Controller Tuning to Enhance LVRT Capability of Grid-Connected Wind Power Generating Plants

This paper investigates the utilization of a STATCOM to enhance the LVRT capability of wind power plants (WPPs) during grid faults. The STATCOM under investigation is tuned using the Water Cycle Algorithm (WCA), Particle Swarm Optimization (PSO), and a hybrid algorithm of both WCA and PSO. Simulations are conducted in MATLAB programming software, using the SimScape power system toolbox, where two test systems are investigated: a 9 MW WPP and the IEEE 39 bus test system. Performance analysis is done by investigating the ability of the WPPs to ride through grid voltage sags, with the incorporation of the STATCOM, independently tuned using WCA, PSO, and further with the hybrid WCA-PSO algorithm. To confirm the effectiveness of the proposed algorithm, simulation results for the three scenarios are compared. Results show that the LVRT capability of the German power system was met for L-G faults, for the 9 MW test system, whereas during LLL-G faults, the WPP only remained online for WCA and WCA-PSO tuned STATCOM. For the IEEE 39 bus system, the WPPs were able to ride through the LLL-G fault. In all scenarios, the WCA-PSO tuned STATCOM resulted in the least voltage, active, and reactive power overshoots.

An active damping control method for direct-drive wind farm with flexible DC transmission system based on the remodeling of dynamic energy branches

In view of the sub-synchronous oscillation in direct-drive wind farm caused by its connection to flexible DC transmission system, an active damping control method based on the remodeling of dynamic energy branches is proposed. First, a dynamic energy model of direct-drive wind farm with flexible DC transmission system is constructed, which contains the interaction energy, dissipation energy and stored energy. The energy model depicts the energy interaction between the control links and the energy transmission process. By analyzing the role of each control link in the transmission system (whether it emits, absorbs or transmits the dynamic energy), the control link that induces the oscillation is found. Thus the source of the energy flows in the whole system is revealed, and the application locations of the compensation branches are determined. On this basis, a parameter optimization strategy for the compensation branches considering both the sub/super synchronous oscillation scenes and the fundamental-frequency characteristics is established, so that the energy distribution can be optimized under sub/super synchronous oscillations. Finally, hardware-in-loop tests are conducted on the RT-LAB platform using the parameters of a real direct-drive wind farm. Simulation results verify that, the proposed strategy can optimize the overall energy distribution in the system through coordinated optimization control. It can quickly suppress the oscillations in both sub and super synchronous frequency bands, without affecting the LVRT capability of the wind generators and the fundamental-frequency characteristics of the system.

Research on Low Voltage Ride through Control of a Marine Photovoltaic Grid-Connected System Based on a Super Capacitor

With the increase of photovoltaic penetration rate, the fluctuation of photovoltaic power generation affects the reliability of ship power grids. Marine PV grid-connected systems with high penetration rates should generally have a low voltage ride-through capability. In the present paper, a strategy in which super capacitors are applied for energy storage in a marine photovoltaic grid-connected system is proposed, and an inverter adopts independent decoupling control of active and reactive currents to improve the LVRT capability of photovoltaic grid-connected systems. In addition, a comprehensive control strategy is also designed to control the supercapacitor, to regulate the active power through the control method of the voltage outer loop and the current inner loop, in order to maintain the DC bus voltage stability. At the same time, the inverter can increase the reactive power output to support the grid voltage. The advantage of this system is in smoothing the power imbalance in a short time, enhancing the low voltage ride-through capability of the photovoltaic grid-connected system, improving the power quality, and ensuring the safety and stability of the ship’s power grid. MATLAB/Simulink were employed to establish a ro-ro ship super capacitor–marine photovoltaic grid-connected power system model and to carry out simulation experiments by setting the grid voltage drop. The results show that when the grid voltage drops, the inverter adjusts the distribution of active and reactive power. The power factor drops from 1 to 0.77, and the effective value of the voltage drop increases from 150 V to 156 V, which proves that this strategy effectively reduces the depth of the grid voltage drop and improves the low voltage ride-through capability of the photovoltaic grid-connected system.

Multimode Inverter Control Strategy for LVRT and HVRT Capability Enhancement in Grid Connected Solar PV System

Grid Connected Photo Voltaic (GCPV) system should be susceptible to grid faults and load curtailment without disconnection and supports in grid stability. During grid faults, there is an increase in dc link voltage, dip in grid voltage which leads to over-current on the grid side. Similarly, when demand is suddenly removed, the voltage at the PCC rises above its nominal value. This leads to possible damage in the PV inverters and hence need to disconnection of GCPV system leading to islanding scenarios. Hence, the GCPV system need to be equipped with Fault Ride Through (FRT) capability to address the issues related to low voltage and high voltage conditions in the grid side. In this work, multimode inverter control strategy is proposed with FRT capability according to grid code compliance. An improved current control technique is proposed as FRT based protection strategy during grid faults and sudden removal of load. According to severity of faults, a fault level detection is developed which triggers the control strategies to generate the reference real and reactive power with respect to the grid code compliance. The performance analysis of the proposed FRT control strategy is implemented in 100 kW two-stage GCPV system in MATLAB/Simulink 2018b environment and tested under low voltage and high voltage ride through conditions. The proposed control strategy is implemented in hardware setup of 1 kW GCPV system. The experimental results prove the effectiveness of the proposed inverter FRT based control strategy in enhancing the system parameters during system disturbances under different modes of operation.

Improvement in LVRT Capability of Wind Energy System Using STATCOM

Improvement in LVRT Capability of Wind Energy System Using STATCOM