Journal Articles
06. A Capacitive Bridge-Type Superconducting Fault Current Limiter to Improve the Transient Performance of DFIG/PV/SG-based Hybrid Power System
IEEE Transactions on Applied Superconductivity
Published on Published on July 02, 2021
Abstract
This paper proposes a capacitive bridge-type superconducting fault current limiter (CB-SFCL) to address the most concerning issue with the grid connected hybrid power system by improving the transient performance. The hybrid system incorporates a doubly fed induction generator (DFIG) based wind farm, a solar photovoltaic (PV) system and a synchronous generator (SG) based power system. The CB-SFCL incorporates a high temperature superconductor (HTS) along with a power capacitor to provide adequate reactive power support before and after the fault. The capacitor is kept inactive during normal operation by a control circuit to ensure a seamless operation. During fault, the capacitor gets connected in series with the HTS and suppress the fault current. The performance of the CB-SFCL is investigated by proper graphical and mathematical analyses and conclusions are obtained by comparing them with that of the conventional bridge-type superconducting fault current limiter (BSFCL) and a capacitive bridge-type fault current limiter (CBFCL). The analyses support the theoretical superiority of the CB-SFCL over the BSFCL and the CBFCL by a satisfying margin.
05. Transient Performance Augmentation of DFIG Based Wind Farms by Nonlinear Control of Flux-Coupling-Type Superconducting Fault Current Limiter
IEEE Transactions on Applied Superconductivity
Published on June 21, 2021
Abstract
Any fault related to grid is a matter of great concern for doubly fed induction generator (DFIG) based power system as DFIGs stator windings are connected to the grid directly. To augment the transient performance of the DFIGs, superconducting fault current limiter (SFCL) is a certified device. To boost the performance of a flux-coupling-type SFCL (FC-SFCL) by ensuing the adaptive use of fault current limiting impedance based on fault severity, rather involving the full impedance unnecessarily, a nonlinear controller (NC) for FC-SFCL (NC-FC-SFCL) is presented in this paper. Reason behind choosing a straightforward NC for this work is to have simple implementation capability with the full flavor of a nonlinear controller. Effectiveness of the NC-FC-SFCL is compared with conventionally controlled FC-SFCL for various fault scenarios. Simulation results suggest that, NC-FC-SFCL can improve the overall fault ride through (FRT) capability which is verified both by graphically and numerically. Additionally, this effective use of the fault limiting impedance guarantees better transient sub-synchronous resonance (SSR) performance, and exhibits better total harmonic distortion responses.
04. Performance improvement of DFIG-based wind farms using NARMA-L2 controlled bridge-type flux coupling nonsuperconducting fault current limiter
IET Generation, Transmission & Distribution
Published on February 17, 2021
Abstract
Doubly-fed induction generators (DFIGs) have drawn prominent interest in the field of wind power generation, but they are vulnerable to grid faults. Grid codes mandate DFIGs to employ a sort of fault ride-through (FRT) technique during faults. Fault current limiters (FCLs) always help to augment the FRT capability of DFIGs and a non-linear controller boosts their performances. In this study, a non-linear auto-regressive moving average-L2 (NARMA-L2) controller-based bridge-type flux coupling non-superconducting FCL (BFC-NSFCL) is proposed to enhance the FRT capability of the wind farm. The authors analysed the performance of the proposed NARMA-L2-based BFC-NSFCL (NL2-BFC-NSFCL) against that of the conventionally used series dynamic braking resistor (SDBR), bridge-type FCL (BFCL), and proportional–integral (PI) controller-based BFCNSFCL (PI-BFC-NSFCL). They tested the performance of the NL2-BFC-NSFCL through multiple temporary and permanent fault scenarios and carried out the mathematical and graphical analysis in MATLAB/Simulink platform. They found that the proposed NL2-BFC-NSFCL's performance surpasses the performances of the SDBR, the BFCL, and the PI-BFC-NSFCL. Moreover, the NL2-BFC-NSFCL has faster system recovery capability after the occurrence of any fault than other competitors.
03. Negative Imaginary Theory-Based Proportional Resonant Controller for Voltage Control of Three-Phase Islanded Microgrid
Journal of Control, Automation and Electrical Systems
Published on July 30, 2020
Abstract
This paper demonstrates the design of robust proportional resonant (PR) controller using negative imaginary (NI) theorem for voltage control of three-phase islanded microgrid (MG) application. While operating MG as the islanded mode, different types of random and unknown load dynamics affect the MG. These loads eventually deteriorate the proper execution of MG-inducing disturbances in voltage and current. Therefore, to improve the performance of the three-phase MG, a simple, second-order controller is designed with the combination of NI theory and PR (NI–PR) controller. This controller is capable of providing higher level of damping as well as excellent stability properties. The stability and effectiveness of this controller are examined through imposing uncertainties, in terms of several load dynamics as well as different fault conditions. The comparison with respect to linear quadratic regulator and model predictive controller also ascertains the robustness of the designed controller. The NI–PR controller and the system are simulated in MATLAB/SIMULINK platform.
02. Neuro Fuzzy Logic Controlled Parallel Resonance Type Fault Current Limiter to Improve the Fault Ride Through Capability of DFIG Based Wind Farm
IEEE Access
Published on June 05, 2020
Abstract
Doubly fed induction generators (DFIGs) are vulnerable to grid related electrical faults. Standards require DFIGs to be disconnected from the grid unless augmented with a fault ride through (FRT) capability. A fault current limiter (FCL) can enhance the overall stability of wind farms and allow them to maintain grid-code requirements. In this paper, a neuro fuzzy logic controlled parallel resonance type fault current limiter (NFLC-PRFCL) is proposed to enhance the FRT capability of the DFIG based wind farm. Theoretical and graphical analysis of the proposed method are carried out by MATLAB/Simulink software. The performance of the NFLC-PRFCL is compared with other documented FCL devices, e.g., the bridge type fault current limiter (BFCL) and the series dynamic braking resistor (SDBR). The performance of the NFLC-PRFCL is also compared with that of the existing fuzzy logic controlled parallel resonance fault current limiter (FLC-PRFCL). From the simulation results, it is found that the NFLC-PRFCL outperforms its competitors and enables the DFIG to maintain a near-seamless performance during various fault events.
01. Fault Ride Through Capability Improvement of DFIG Based Wind Farm Using Nonlinear Controller Based Bridge-Type Flux Coupling Non-Superconducting Fault Current Limiter
Energies
Published on April 03, 2020
Abstract
High penetration of Doubly Fed Induction Generator (DFIG) into existing power grid can attribute complex issues as they are very sensitive to the grid faults. In addition, Fault Ride Through (FRT) is one of the main requirements of the grid code for integrating Wind Farms (WFs) into the power grid. In this work, to enhance the FRT capability of the DFIG based WFs, a Bridge-Type Flux Coupling Non-Superconducting Fault Current Limiter (BFC-NSFCL) is proposed. The effectiveness of the proposed BFC-NSFCL is evaluated through performance comparison with that of the Bridge-Type Fault Current Limiter (BFCL) and Series Dynamic Braking Resistor (SDBR). Moreover, a dynamic nonlinear controller is also proposed for controlling the operation of the BFC-NSFCL. Extensive simulations are carried out in the MATLAB/SIMULINK environment for both symmetrical and unsymmetrical temporary as well as permanent faults. Based on the simulation results and different numerical analysis, it is found that the proposed nonlinear controller based BFC-NSFCL is very effective in enhancing the FRT capability of the WF. Also, the BFC-NSFCL outperforms the conventional BFCL and SDBR by maintaining a near-seamless performance during various grid fault situations.
Conference Papers
01. Implementation of Capacitive Bridge-Type Superconducting Fault Current Limiter to Improve the FRT Capability of DFIG Based Wind Generator
2020 IEEE International Conference on Applied Superconductivity and Electromagnetic Devices (ASEMD)
October 16-18, 2020, Tianjin, China
Abstract
A capacitive bridge-type superconducting fault current limiter (CB-SFCL) is proposed in this paper for the improvement of fault ride through (FRT) capability of DFIG based wind power generation system (WPGS). The CB-SFCL incorporates a power capacitor in series with a high temperature superconductor coil (HTSC). Performance of the CB-SFCL is evaluated by comparing it with the conventional bridge-type superconducting fault current limiter (BSFCL). Simulation results show that the CB-SFCL is superior to the BSFCL in enhancing the stability of the WPGS incorporated with DFIG.
02. Optimized Use of Flux Coupling Superconducting Fault Current Limiter to Improve the Performance of DFIG Based Wind Power Generation System
2020 IEEE International Conference on Applied Superconductivity and Electromagnetic Devices (ASEMD)
October 16-18, 2020, Tianjin, China
Abstract
This paper proposes a nonlinear control-based flux coupling superconducting fault current limiter (NC-FC-SFCL) to enhance the transient performances of doubly fed induction generator (DFIG) based wind power system. This nonlinear control helps to utilize the fault limiting impedance of flux coupling superconducting fault current limiter (FC-SFCL) adaptively which suits the nonlinear dynamics of the power system more appropriately. This proposed NC-FC-SFCL’s efficacy is compared with conventionally controlled FC-SFCL and it is found that the NC-FC-SFCL is superior in each aspect than the FC-SFCL.
03. Enhancement of FRT Capability of DFIG Based Wind Farm by a Hybrid Superconducting Fault Current Limiter With Bias Magnetic Field
2020 IEEE International Conference on Power Electronics, Smart Grid and Renewable Energy (PESGRE2020)
January 02-04, 2020, Cochin, India
Abstract
Doubly fed induction generators (DFIGs) have some enthralling features which made them one of the most popular choices in power system. However, any kind of system abnormalities will directly affect the DFIGs as their stator windings are directly linked to the grid. To comply with the grid code, every DFIG based wind farms are required to ride through the fault keeping the healthy part of the system undisturbed. So, fault ride through (FRT) capability improvement is a mandatory requirement for every DFIG based wind farms. Superconducting fault current limiters (SFCLs) have been popular for decades in this regard. In this paper, a new hybrid superconducting fault current limiter (HSFCL) with bias magnetic field is put forth. The HSFCL is designed by combining a double split reactor with a high temperature superconducting (HTS) magnet which is non-inductive. For the validation, its performance has been compared with that of bridge-type fault current limiter (BFCL) and series dynamic braking resistor (SDBR). MATLAB/Simulink environment is used to perform the simulations. It has been found that, the proposed HSFCL outperforms both BFCL and SDBR.
04. Fault Ride Through Capability Improvement of DFIG Based Wind Farms Using Active Power Controlled Bridge Type Fault Current Limiter
2019 North American Power Symposium (NAPS)
October 13-15, Wichita, KS, USA
Abstract
Doubly fed induction generators (DFIGs) provide some intriguing features which made them one of the most popular choices in power system. However, since the stator windings of a DFIG are attached to the grid, they are severely affected by faults. To comply with the grid code, a DFIG must stay connected to the grid during faults for a stable operation of the power system. Hence, the requirement of fault ride through (FRT) capability improvement is mandatory for every DFIG based wind farms. Bridge type fault current limiters (BFCLs) are one of the newest additions to solve the issues with FRT capability. There are several existing schemes to control a BFCL. However, no attempt had been taken to use the active power of the DFIG for controlling the BFCL. In this paper, a new control scheme using the active power of the system is proposed. Later, the system responses for different control schemes have been compared. Simulations have been carried out in Matlab/Simulink environment. It has been found that, the proposed control of BFCL using active power provides better FRT capability improvement than other existing schemes.
05. Fault Ride Through Capability Enhancement of DFIG Based Wind Farm Using Advanced Converter Topology
2019 International Conference on Computer, Communication, Chemical, Materials and Electronic Engineering (IC4ME2)
July 11-12, Rajshahi, Bangladesh
Abstract
In last few years, the most accepted and prominent choice in wind farm technology is Doubly Fed Induction Generators (DFIGs). But it is vulnerable to faults, especially which relate to grid, as its stator winding is directly attached to the grid. For uninterrupted supply of power, the DFIG requires to be connected to the grid during the faults according to the grid code. Hence, improving the Fault Ride Through (FRT) capability is one of the major concerns to ensure the stable operation of DFIG based wind farms. This paper is focused on the performance of various converter-inverter topologies for transient stability analysis of DFIG. Thus far, two level and three level neutral point clamped converter-inverter topologies have been implemented in FRT analysis. However, the analysis has not yet been performed for the two newly introduced advanced topologies i.e. flying capacitor and Zsource model. Simulations had been executed using PSCAD/EMTDC simulation platform. The effect of different converter-inverter topologies on the terminal voltage and the DC-link voltage were demonstrated and compared. Simulation results show that flying capacitor model outperforms all the other converter-inverter topologies by all aspects.