In present electrical power systems, wind energy conversion systems based on doubly fed induction generators represent one of the most commonly accepted systems in the global market due to their ...excellent performance under different power system operations. The high wind energy penetration rate makes it challenging for these wind turbines to follow grid code requirements. All operations of a wind energy system during a dip in voltage require special attention; these operations are critically known as fault ride-through and low voltage ride-through. In this paper, various fault ride-through techniques of doubly fed induction generator-based wind energy conversion systems, such as protective circuitry, reactive power injection, and control methods for transient and steady state operations, have been presented to improve the performance. During system disturbances, protective circuitry or control mechanisms are typically used to limit the over-current of the rotor and the generated inappropriate DC link over-voltage. Simultaneously, the reactive power injection system overcomes the reactive power scarcity and enhances the transient response, further limiting the DC bus voltage and rotor current. This review paper compares and suggests appropriate FRT methods that are driven by external modifications and internal system improvements. Furthermore, typical case studies are discussed to illustrate and support the FRT system. The impact of each case study was evaluated and analyzed using the results obtained from the MATLAB/Simulink application and the OPAL-RT (OP4500) real time simulator (RTS).
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
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The sensorless speed control of permanent magnet synchronous motor (PMSM) is gaining popularity in hybrid electric vehicle (HEV) applications leading to its enhanced safety, reliability, and ...cost savings. Speed control using vector control for PMSM‐fed HEV requires the speed encoder. When the speed sensor information fails, the inverter must ensure power delivery to the PMSM continuously by estimating the speed; this mode of operation is referred as limp‐home mode in HEV. In this paper, a speed sensorless scheme has been proposed for PMSM‐based HEV during limp‐home mode operation. This paper presents a model reference adaptive system (MRAS) speed estimator based on an adaptive neural network controller (NNC) for speed estimation of PMSM. In the HEV application, in case of speed/position encoder failure, the speed of the PMSM can be estimated by stator flux using stator current.The proposed method employs stator currents in the reference model to eliminate the DC drift problem. Furthermore, the NNC is employed in the adaptation mechanism to improve the Federal Test Procedure (FTP75) driving cycle performance. The performance of the proposed control scheme has been validated with dSPACE 1104 R & D rapid development controller using vector control for the PMSM during variable speed and torque, including the zero‐speed applications
This paper presents a model reference adaptive system (MRAS) speed observer based on an adaptive neural network controller for speed estimation of permanent magnet synchronous motor (PMSM) fed hybrid electric vehicle. When the speed sensor information fails, the inverter present in the power train of the vehicle must continuously ensure power delivery to the PMSM by estimating the speed; this mode of operation is referred to as limp‐home mode in EV. The proposed method employs stator currents in the reference model to eliminate the DC drift problem. The ANN‐based stator current MRAS speed observer has been tested for different driving cycles, such as FTP75, Indian urban, Indian highway drive cycle, and staircase reference input. The proposed control scheme enhances the system's dynamic performance by achieving better control and accuracy in speed regulation at different driving cycles, which is verified by comparing standard deviations (SDs) and relative error of speed response.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
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In this paper, a stator current‐based model reference adaptive system (SCMRAS) for indirect vector control of induction motor fed to hybrid electric vehicle (HEV) for improving the transient ...response during limp home period has been proposed. In the proposed SCMRAS, the measured stator currents are employed in voltage model to eliminate the integrator in reference model. The stator currents are estimated and are compared with actual current components to estimate the rotor speed. Further, to improve the performance of SCMRAS during limp home period, the PI controller in the adaptation mechanism is replaced with type 2 fuzzy logic controller (T2FLC). The prototype model of the proposed SCMRAS using dSPACE DS 1104 R&D controller board has been developed for implementing speed sensorless indirect vector control of induction motor drive. The performance of SCMRAS and proposed SCMRAS using T2FLC estimators during limp home period is compared.
To eliminate the integrator in the reference model, the proposed stator current model reference adaptive system uses the measured stator currents in the voltage model. The stator currents are estimated and compared to the actual current to estimate the rotor speed. The PI controller in the adaption mechanism is replaced with a type 2 fuzzy logic controller to improve Induction motor drive fed Hybrid electrical vehicle dynamic performance during the limp‐home period.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Torque ripple content and variable switching frequency operation of conventional direct torque control (DTC) are reduced by the integration of space vector modulation (SVM) into DTC. Integration of ...space vector modulation to conventional direct torque control known as SVM-DTC. It had been more frequently used method in renewable energy and machine drive systems. In this paper, SVM-DTC is used to control the rotor side converter (RSC) of a wind driven doubly-fed induction generator (DFIG) because of its advantages such as reduction of torque ripples and constant switching frequency operation. However, flux and torque ripples are still dominant due to distorted current waveforms at different operations of the wind turbine. Therefore, to smoothen the torque profile a Neural Network Controller (NNC) based SVM-DTC has been proposed by replacing the PI controller in the speed control loop of the wind turbine controller. Also, stability analysis and simulation study of DFIG using process reaction curve method (RRCM) are presented. Validation of simulation study in MATLAB/SIMULINK environment of proposed wind driven DFIG system has been performed by laboratory developed prototype model. The proposed NNC based SVM-DTC yields superior torque response and ripple reduction compared to other methods.
Summary
In this paper, an indirect vector control (IVC) technique for the stand‐alone self‐excited induction generator (SASEIG)‐based wind energy conversion system (WECS) is proposed to independently ...control torque, active power, reactive power, and DC voltage for variable wind speed operation without fault and constant wind speed operation with single line‐to‐ground (LG) fault condition. This independent control of the WECS is obtained by using two‐level back to back converter, ie, machine side converter (MSC) and load side converter (LSC). To improve the dynamic response of the system during wind speed changes and fault operation, the PI controller in IVC is replaced with fuzzy logic controller (FLC). IVC of SEIG‐based WECS has been simulated in MATLAB/SIMULINK software, and prototype model of the proposed WECS is designed to experimentally validate the performance using dSPACE DS‐1104 R&D controller board. The results demonstrate that the performance of the proposed FLC‐based IVC controller is better than that the conventional PI controller–based IVC during variable speed and LG fault operations.
Model reference adaptive system schemes offer simpler implementation and require less computational effort compared to other speed sensorless methods. The performance of rotor flux based model ...reference adaptive system schemes at low-speed operation is poor because of parameter sensitivity and presence of the integrator in the reference model. As stator resistance inevitably varies with temperature, for accurate operation at low speeds, an appropriate online identification algorithm for the stator resistance is required. In this article, a neural network based parallel stator resistance and rotor speed estimator has been proposed to simultaneously rectify the limitation of model reference adaptive system schemes, i.e., stator resistance variation and DC offset due to integrator, employing a neutral network in stator resistance estimator and modifying the reference model by adding a compensating voltage term. An indirect sensorless vector control scheme has been simulated and experimentally validated using the dSPACE DS-1104 R&D controller board (dSPACE GmbH, Paderborn, Germany) to verify the performance of drives at different operating conditions.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
Paper presents the comparative studies between indirect vector control (IVC) based Grid-connected SEIG-based Wind Energy Conversion Systems (GCSEIGWECS) and Direct torque control (DTC) with Space ...Vector Pulse width Modulation (SVPWM) based GCSEIGWECS. The frequency converter includes a Rotor side Connected converter (RSCC) and Grid Side Connected Converter (GSCC) is used to control torque ripples, rotor speed overshoot, undershoot, active power, reactive power, and DC-Link Voltage. The Sinusoidal Pulse Width Modulation (SPWM) technique for RSCC and Space Vector Pulse width Modulation (SVPWM) for GSCC have been proposed. The different topologies have been implemented using MATLAB/SIMULINK tools.
This paper presents the comparison of PI controller-based stand-alone self-excited induction generator-based wind energy conversion systems and ANN(artificial neural network) based SAWECS. A novel ...SPWM technique is proposed for the generator-side connected converter and a space modulation technique is proposed for load side connected converter. The Generator side converter is to control the real power and reactive power and the load side converter is to control the dc link voltage by the indirect vector control(IVC) method. The proposed SASEIG-based WECS using the different converters are simulated in MATLAB/SIMULINK environment and they are compared at different operating conditions.
This paper presents the waveform of Three level converters-based SAWES (stand-alone wind energy system) compared with Five level converter-based SAWES. SPWM technique is proposed for rotor-connected ...converter and space modulation technique is proposed for load-connected inverter fed SASEIG-based WECS. This converter consists of Rotor connected converter (RCC) to control the real part and imaginary part of apparent power whereas a Load connected Converter (LCC) regulates the DC voltage by using Indirect Vector Control (IVC). The proposed SASEIG-based WECS using the different converters is simulated in MATLAB/SIMULINK environment and they are compared at different operating conditions.
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