The Experts below are selected from a list of 249 Experts worldwide ranked by ideXlab platform
Jeyraj Selvaraj - One of the best experts on this subject based on the ideXlab platform.
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Grid-connected photovoltaic system employing a single-phase T-type cascaded H-bridge inverter
Solar Energy, 2020Co-Authors: Aamir Amir, Jeyraj Selvaraj, Asim Amir, Nasrudin Abd RahimAbstract:Abstract This paper presents the control and application of a single-phase T-type nine-level cascaded H-Bridge (TCHB) multilevel inverter (MLI) topology. This paper focuses on the effectiveness of the TCHB and its control by presenting the inverter operation based on a PI current controller along with a Maximum Power Point Tracking (MPPT) scheme to realize a grid-tied photovoltaic (PV) system and a novel PWM method offering self-balancing at the DC-link capacitors. In order to attain gating Signals for power transistors (IGBTs), the TCHB employs a PWM with one Triangular Carrier Signal and eight reference Signals. In addition, a mathematical modelling of the PWM method, along with a theoretical explanation of the self-balancing process has also been provided. To prove the effectiveness of the proposed TCHB topological design, it has been comparatively analysed against other fundamental MLI and symmetric CHB topologies. In addition, to corroborate the working of the control and the PV system application, employing TCHB inverter offering nine output voltage levels (±2Vdc, ±2¾Vdc, ±Vdc, ±½Vdc, 0), simulation and hardware results have been presented.
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Single-Phase Seven-Level Grid-Connected Inverter for Photovoltaic System
IEEE Transactions on Industrial Electronics, 2011Co-Authors: Nasrudin Abd Rahim, Krismadinata Chaniago, Jeyraj SelvarajAbstract:This paper proposes a single-phase seven-level inverter for grid-connected photovoltaic systems, with a novel pulsewidth-modulated (PWM) control scheme. Three reference Signals that are identical to each other with an offset that is equivalent to the amplitude of the Triangular Carrier Signal were used to generate the PWM Signals. The inverter is capable of producing seven levels of output-voltage levels (Vdc, 2Vdc/3, Vdc/3, 0, -Vdc, -2Vdc/3, -Vdc/3) from the dc supply voltage. A digital proportional-integral current-control algorithm was implemented in a TMS320F2812 DSP to keep the current injected into the grid sinusoidal. The proposed system was verified through simulation and implemented in a prototype.
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A novel multi-string five-level PWM inverter for photovoltaic application
2011 IEEE International Electric Machines & Drives Conference (IEMDC), 2011Co-Authors: Nasrudin Abdul Rahim, Jeyraj SelvarajAbstract:This paper presents a single-phase multi-string five-level PV inverter topology for grid-connected photovoltaic (PV) systems with a novel PWM control scheme. Three PV strings are cascaded together in parallel configuration and connected to a five-level inverter to produce output voltage in five levels: zero, +1/2V dc ; V dc ; −1/2V dc and −V dc . Two reference Signals identical to each other with an offset equivalent to the amplitude of the Triangular Carrier Signal were used to generate PWM Signals for the switches. DSP TMS320F2812 is used to implement this PWM switching scheme together with a digital PI current control algorithm. The inverter offers much less THD and can operate at near unity power factor. The validity of the proposed inverter is verified through a prototype. The experimental results are compared with conventional single-phase multi-string three-level grid-connected PWM inverter.
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Five-level inverter with dual reference modulation technique for grid-connected PV system
Renewable Energy, 2010Co-Authors: Nasrudin Abd Rahim, Jeyraj Selvaraj, C. KrismadinataAbstract:Abstract This paper presents a single-phase five-level grid-connected PV inverter with a novel dual reference modulation technique. Two reference Signals identical to each other with an offset equivalent to the amplitude of the Triangular Carrier Signal were used to generate PWM Signals. The inverter consists of a full-bridge inverter and an auxiliary circuit comprising four diodes and a switch. The inverter produces output voltage in five levels: zero, +1/2 V dc , V dc , −1/2 V dc and − V dc . A digital PI current control algorithm is implemented in DSP TMS320F2812 to keep the current injected into the grid sinusoidal and to have high dynamic performance with low THD. The validity of the proposed inverter is verified through simulation and implemented in a prototype. The experimental results are compared with conventional single-phase three-level grid-connected PWM inverter in terms of THD.
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Multistring Five-Level Inverter With Novel PWM Control Scheme for PV Application
IEEE Transactions on Industrial Electronics, 2010Co-Authors: Nasrudin Abd Rahim, Jeyraj SelvarajAbstract:This paper presents a single-phase multistring five-level photovoltaic (PV) inverter topology for grid-connected PV systems with a novel pulsewidth-modulated (PWM) control scheme. Three PV strings are cascaded together in parallel configuration and connected to a five-level inverter to produce output voltage in five levels: zero, +1/2V dc, V dc, -1/2V dc, and -V dc. Two reference Signals that were identical to each other with an offset that was equivalent to the amplitude of the Triangular Carrier Signal were used to generate PWM Signals for the switches. DSP TMS320F2812 is used to implement this PWM switching scheme together with a digital proportional-integral current control algorithm. The inverter offers much less total harmonic distortion and can operate at near-unity power factor. The validity of the proposed inverter is verified through simulation and implemented in a prototype. The experimental results are compared with a conventional single-phase multistring three-level grid-connected PWM inverter.
Nasrudin Abd Rahim - One of the best experts on this subject based on the ideXlab platform.
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Grid-connected photovoltaic system employing a single-phase T-type cascaded H-bridge inverter
Solar Energy, 2020Co-Authors: Aamir Amir, Jeyraj Selvaraj, Asim Amir, Nasrudin Abd RahimAbstract:Abstract This paper presents the control and application of a single-phase T-type nine-level cascaded H-Bridge (TCHB) multilevel inverter (MLI) topology. This paper focuses on the effectiveness of the TCHB and its control by presenting the inverter operation based on a PI current controller along with a Maximum Power Point Tracking (MPPT) scheme to realize a grid-tied photovoltaic (PV) system and a novel PWM method offering self-balancing at the DC-link capacitors. In order to attain gating Signals for power transistors (IGBTs), the TCHB employs a PWM with one Triangular Carrier Signal and eight reference Signals. In addition, a mathematical modelling of the PWM method, along with a theoretical explanation of the self-balancing process has also been provided. To prove the effectiveness of the proposed TCHB topological design, it has been comparatively analysed against other fundamental MLI and symmetric CHB topologies. In addition, to corroborate the working of the control and the PV system application, employing TCHB inverter offering nine output voltage levels (±2Vdc, ±2¾Vdc, ±Vdc, ±½Vdc, 0), simulation and hardware results have been presented.
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Single-Phase Seven-Level Grid-Connected Inverter for Photovoltaic System
IEEE Transactions on Industrial Electronics, 2011Co-Authors: Nasrudin Abd Rahim, Krismadinata Chaniago, Jeyraj SelvarajAbstract:This paper proposes a single-phase seven-level inverter for grid-connected photovoltaic systems, with a novel pulsewidth-modulated (PWM) control scheme. Three reference Signals that are identical to each other with an offset that is equivalent to the amplitude of the Triangular Carrier Signal were used to generate the PWM Signals. The inverter is capable of producing seven levels of output-voltage levels (Vdc, 2Vdc/3, Vdc/3, 0, -Vdc, -2Vdc/3, -Vdc/3) from the dc supply voltage. A digital proportional-integral current-control algorithm was implemented in a TMS320F2812 DSP to keep the current injected into the grid sinusoidal. The proposed system was verified through simulation and implemented in a prototype.
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Five-level inverter with dual reference modulation technique for grid-connected PV system
Renewable Energy, 2010Co-Authors: Nasrudin Abd Rahim, Jeyraj Selvaraj, C. KrismadinataAbstract:Abstract This paper presents a single-phase five-level grid-connected PV inverter with a novel dual reference modulation technique. Two reference Signals identical to each other with an offset equivalent to the amplitude of the Triangular Carrier Signal were used to generate PWM Signals. The inverter consists of a full-bridge inverter and an auxiliary circuit comprising four diodes and a switch. The inverter produces output voltage in five levels: zero, +1/2 V dc , V dc , −1/2 V dc and − V dc . A digital PI current control algorithm is implemented in DSP TMS320F2812 to keep the current injected into the grid sinusoidal and to have high dynamic performance with low THD. The validity of the proposed inverter is verified through simulation and implemented in a prototype. The experimental results are compared with conventional single-phase three-level grid-connected PWM inverter in terms of THD.
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Multistring Five-Level Inverter With Novel PWM Control Scheme for PV Application
IEEE Transactions on Industrial Electronics, 2010Co-Authors: Nasrudin Abd Rahim, Jeyraj SelvarajAbstract:This paper presents a single-phase multistring five-level photovoltaic (PV) inverter topology for grid-connected PV systems with a novel pulsewidth-modulated (PWM) control scheme. Three PV strings are cascaded together in parallel configuration and connected to a five-level inverter to produce output voltage in five levels: zero, +1/2V dc, V dc, -1/2V dc, and -V dc. Two reference Signals that were identical to each other with an offset that was equivalent to the amplitude of the Triangular Carrier Signal were used to generate PWM Signals for the switches. DSP TMS320F2812 is used to implement this PWM switching scheme together with a digital proportional-integral current control algorithm. The inverter offers much less total harmonic distortion and can operate at near-unity power factor. The validity of the proposed inverter is verified through simulation and implemented in a prototype. The experimental results are compared with a conventional single-phase multistring three-level grid-connected PWM inverter.
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A novel PWM multilevel inverter for PV application
IEICE Electronics Express, 2009Co-Authors: Nasrudin Abd Rahim, Jeyraj Selvaraj, Krismadinata ChaniagoAbstract:In this paper, a single-phase five-level PV inverter topology for grid-connected photovoltaic (PV) system with a novel PWM control scheme is presented. PWM Signals were generated by comparing two reference Signals identical to each other with an offset equivalent to the amplitude of the Triangular Carrier Signal. A digital PI current control algorithm is implemented to keep the current injected into the grid sinusoidal and to have high dynamic performance with rapidly changing atmospheric conditions and low THD. This new configuration of the proposed inverter is implemented in a prototype.
Samet Biricik - One of the best experts on this subject based on the ideXlab platform.
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Super Twisting Algorithm Based Sliding Mode Control Method for Single-Phase Dynamic Voltage Restorers
2019 2nd International Conference on Smart Grid and Renewable Energy (SGRE), 2019Co-Authors: Hasan Komurcugil, Samet Biricik, Ebrahim BabaeiAbstract:This paper presents a super twisting algorithm (STA) based sliding mode control (SMC) method for single-phase dynamic voltage restorers (DVRs). The proposed control method eliminates chattering and achieves constant switching frequency. The STA is usually considered as high-order sliding mode (HOSM). The main advantage of HOSM is that its acts on the high-order derivatives of the sliding surface while preserving the inherent advantages of first-order sliding modes and reducing the chattering phenomenon while increasing the accuracy. Hence, the consequence of applying STA in DVR control is that a continuous control input is obtained which can be compared with the Triangular Carrier Signal to produce the pulse width modulation (PWM) Signals. The theoretical considerations and analytical results are verified through computer simulations. It is shown that the load voltage is maintained at desired level under voltage sags and voltage swells in the grid.
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Time-Varying and Constant Switching Frequency-Based Sliding-Mode Control Methods for Transformerless DVR Employing Half-Bridge VSI
IEEE Transactions on Industrial Electronics, 2017Co-Authors: Hasan Komurcugil, Samet BiricikAbstract:This paper presents time-varying and constant switching frequency based sliding-mode control (SMC) methods for three-phase transformerless dynamic voltage restorers (TDVRs) which employ half-bridge voltage source inverter. An equation is derived for the time-varying switching frequency. However, since the time-varying switching frequency is not desired in practice, a smoothing operation is applied to the sliding surface function within a narrow boundary layer with the aim of eliminating the chattering effect and achieving a constant switching frequency operation. The control Signal obtained from the smoothing operation is compared with a Triangular Carrier Signal to produce the pulse width modulation Signals. The feasibility of both SMC methods has been validated by experimental results obtained from a TDVR operating under highly distorted grid voltages and voltage sags. The results obtained from both methods show excellent performance in terms of dynamic response and low total harmonic distortion (THD) in the load voltage. However, the constant switching frequency-based SMC method not only offers a constant switching frequency at all times and preserves the inherent advantages of the SMC, but also leads to smaller THD in the load voltage than that of time-varying switching frequency-based SMC method.
Hasan Komurcugil - One of the best experts on this subject based on the ideXlab platform.
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Super Twisting Algorithm Based Sliding Mode Control Method for Single-Phase Dynamic Voltage Restorers
2019 2nd International Conference on Smart Grid and Renewable Energy (SGRE), 2019Co-Authors: Hasan Komurcugil, Samet Biricik, Ebrahim BabaeiAbstract:This paper presents a super twisting algorithm (STA) based sliding mode control (SMC) method for single-phase dynamic voltage restorers (DVRs). The proposed control method eliminates chattering and achieves constant switching frequency. The STA is usually considered as high-order sliding mode (HOSM). The main advantage of HOSM is that its acts on the high-order derivatives of the sliding surface while preserving the inherent advantages of first-order sliding modes and reducing the chattering phenomenon while increasing the accuracy. Hence, the consequence of applying STA in DVR control is that a continuous control input is obtained which can be compared with the Triangular Carrier Signal to produce the pulse width modulation (PWM) Signals. The theoretical considerations and analytical results are verified through computer simulations. It is shown that the load voltage is maintained at desired level under voltage sags and voltage swells in the grid.
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Time-Varying and Constant Switching Frequency-Based Sliding-Mode Control Methods for Transformerless DVR Employing Half-Bridge VSI
IEEE Transactions on Industrial Electronics, 2017Co-Authors: Hasan Komurcugil, Samet BiricikAbstract:This paper presents time-varying and constant switching frequency based sliding-mode control (SMC) methods for three-phase transformerless dynamic voltage restorers (TDVRs) which employ half-bridge voltage source inverter. An equation is derived for the time-varying switching frequency. However, since the time-varying switching frequency is not desired in practice, a smoothing operation is applied to the sliding surface function within a narrow boundary layer with the aim of eliminating the chattering effect and achieving a constant switching frequency operation. The control Signal obtained from the smoothing operation is compared with a Triangular Carrier Signal to produce the pulse width modulation Signals. The feasibility of both SMC methods has been validated by experimental results obtained from a TDVR operating under highly distorted grid voltages and voltage sags. The results obtained from both methods show excellent performance in terms of dynamic response and low total harmonic distortion (THD) in the load voltage. However, the constant switching frequency-based SMC method not only offers a constant switching frequency at all times and preserves the inherent advantages of the SMC, but also leads to smaller THD in the load voltage than that of time-varying switching frequency-based SMC method.
Hong-hee Lee - One of the best experts on this subject based on the ideXlab platform.
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Dual Three-Phase Indirect Matrix Converter With Carrier-Based PWM Method
IEEE Transactions on Power Electronics, 2014Co-Authors: Tuyen D. Nguyen, Hong-hee LeeAbstract:This paper proposes an indirect matrix converter (IMC) topology with dual three-phase outputs and its effective Carrier-based pulse width modulation (PWM) method. The proposed IMC topology can independently supply ac power for two three-phase loads from a single three-phase ac power source. This converter consists of a rectifier stage used in traditional three-phase IMC and a five-leg inverter. Besides a proposed IMC topology, the Carrier-based PWM method suitable for this converter is also introduced. The proposed PWM method is easily implemented by using only one symmetrical Triangular Carrier Signal to generate the PWM Signals for a rectifier and five-leg inverter. Proposed IMC topology features the advantages of conventional three-phase IMC, such as sinusoidal input/output current waveforms, controllable input power factor, and simple commutation at the rectifier stage. Analysis, simulation, and experimental results are provided to demonstrate the advantages of the proposed IMC topology with dual three-phase outputs and to validate the effectiveness of the applied modulation strategy.
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A Carrier-Based Pulse Width Modulation Method for Indirect Matrix Converters
Journal of Power Electronics, 2012Co-Authors: Dinh-tuyen Nguyen, Hong-hee Lee, Tae-won ChunAbstract:This paper proposes a Carrier-based pulse width modulation (PWM) method to control an indirect matrix converter (IMC) by analyzing the relationship between the space vector PWM (SVPWM) and the Carrier-based PWM. The complexity of the SVPWM method for an IMC can be reduced by using an equivalent Carrier-based PWM method. The advantage of the proposed algorithm is its ability use only one symmetrical Triangular Carrier Signal to generate the gate Signals for all of the power switches in both the rectifier and inverter stages as compared to the conventional method where the Carrier Signal used in the rectifier stage is different from that of the inverter stage. In addition, by using a suitable offset voltage component in the modulation Signals, the output voltage magnitude reaches 0.866 of the input voltage magnitude. Simulation and experimental results are provided in order to validate the proposed method.
