Single Ended Primary Inductor Converter Converter Research Articles

Modified Bridgeless SEPIC Rectifier for Power Factor Correction with Reduced Switch Stress Operating in Continuous Conduction Mode

In this paper, a high performance single-phase modified bridgeless AC–DC converter with reduced switch voltage stress for power factor correction (PFC) is introduced. The proposed converter is based on a single-ended primary-inductance converter (SEPIC) to meet the demands of PFC to unity and output voltage regulation. To reduce the number of components, the input bridge is combined with the SEPIC converter since the conventional SEPIC PFC is suffering with high conduction losses. It offers many advantages, such as fewer semiconductor devices in current flowing path which lead to improve the thermal management, low stress on each component, improved efficiency, high power factor compared to classical converter. Detailed analysis and design equations of the converter are presented. Simulation and experimental results are discussed for a 300[Formula: see text]W prototypeunder the universal input voltage (85–235[Formula: see text]V) to validate the performance of the converter.

Adaptive and Nonlinear Control Techniques Applied to SEPIC Converter in DC-DC, PFC, CCM and DCM Modes Using HIL Simulation

In this paper, we propose adaptive nonlinear controllers for the Single-Ended Primary Inductance Converter (SEPIC). We also consider four distinct situations: AC-DC, DC-DC, Continuous Conduction Mode (CCM) and Discontinuous Conduction Mode (DCM). A comparative analysis between classic linear and nonlinear approaches to regulate the control loop is made. Three adaptive nonlinear control laws are designed: Feedback Linearization Control (FLC), Passivity-Based Control (PBC) and Interconnection and Damping Assignment Passivity-Based Control (IDAPBC). In order to compare the performance of these control techniques, numerical simulations were made in Software and Hardware in the Loop (HIL) for nominal conditions and operation disturbances. We recommend adaptive controllers for the two different situations: Adaptive Passivity-Based Feedback Linearization Control (APBFLC) for the PFC (Power Factor Correction) AC-DC system and IDAPBC-BB (IDAPBC Based on Boost converter) for the regulator DC-DC system.

A Commercial Low Cost, Highly Efficient UC3842 based High Brightness LED (HBLED) Lamp

The conventional lighting sources like incandescent and fluorescent lamps are replaced by High Brightness Light Emitting Diodes (HB-LEDs). In this paper, a HBLED driver using a Single Ended Primary Inductor Converter (SEPIC) with input Power Factor Correction (PFC) is presented. PFC is accomplished using a commercial inexpensive Peak Current Mode Controller (PCMC) IC UC3842 is newly combined with SEPIC converter. Extensive simulation results are carried out and a laboratory prototype to power 18W LED array from AC mains is implemented and the results are presented in detail.

Isolated SEPIC DC–DC Converter With Ripple-Free Input Current and Lossless Snubber

This paper proposes an isolated single-ended primary-inductor converter (SEPIC) dc–dc converter with ripple-free input current and lossless snubber. The proposed converter is based on a conventional isolated SEPIC converter to enable electrical isolation and high voltage gain using a coupled inductor. The input current ripple is significantly reduced by utilizing an auxiliary circuit that also functions as a lossless snubber circuit with an additional diode. Moreover, the maximum switch voltage stress is clamped to a low voltage by the snubber circuit. Therefore, a low voltage rating mosfet that has low $R_{{\rm{DS(on)}}}$ can be utilized as a main switch device. Hence, the total power efficiency is improved. Experimental results from a 100 W prototype, which are presented to verify the theoretic analysis and performance of the proposed converter.

Hybrid converter topology for reducing torque ripple of BLDC motor

This study investigates the torque ripple performance of brushless DC (BLDC) motor drive system by integrating both modified single-ended primary inductor converter (SEPIC) and silicon carbide metal–oxide–semiconductor field-effect transistor based three-level neutral-point-clamped (NPC) inverter. In BLDC motor, the high commutation torque ripple is an important origin of vibration, speed ripple and prevents the use of the BLDC motor drive system in high-performance and high-precision applications. For torque ripple reduction, the modified SEPIC converter is employed at the entrance of the three-level NPC inverter, which regulates the DC-link voltage according to the motor speed. Moreover, the three-level NPC inverter is employed as a second-stage converter to suppress current ripple for further torque ripple reduction. Finally, the performance of the proposed hybrid converter topology is verified by simulation and laboratory experimental results.

Design and analysis of a novel SEPIC‐based multi‐input DC/DC converter

A novel single-ended primary-inductor converter (SEPIC)-based multi-input DC/DC converter is presented. The structure inherits all the advantages of the SEPIC converter such as step-up/down capability without inverting the polarity of the regulated output voltage and using a series capacitor to couple energy from the input to the output. The presented converter has a bidirectional input port, in which the energy storage system (ESS) can be connected, and several unidirectional input ports. Hybridising several alternative energy sources is achievable by the proposed converter. In addition, the load power can be flexibly divided among various power sources. Due to the buck-boost characteristic of the presented converter, it is suitable to charge-discharge the ESS and to extract maximum power from the photovoltaic panels. Based on the charging state of the ESS, two operation modes are defined. Steady-state and dynamic behaviour of the proposed converter is analysed thoroughly. Experimental results are also provided to verify the analysis and feasibility of the proposed converter.

Analysis and Design of Single Phase Power Factor Correction using DC-DC SEPIC Converter with Bang-Bang and PSO based Fixed PWM Techniques

This paper presents the design and analysis of single phase Power factor correction (PFC) using DC-DC Single Ended Primary Inductance converter (SEPIC).The proposed system applies cascade approach where outer loop is implemented with Particle Swarm Optimization (PSO) tuned PI controller to synchronize the output voltage with reference voltage and inner current loop is controlled by Bang-Bang/PSO based Fixed PWM control techniques. The performance characteristics of these two approaches are analyzed by simulation results. The PSO based Control strategy yields an advantages of unity power factor (UPF), low percent THD(%THD), well synchronized output voltage for the variations in the line and load. It also provides efficient tracking of reference voltage compared to Bang-Bang control.

Modelling, design and stability analysis of an improved SEPIC converter for renewable energy systems

ABSTRACTIn this paper, a detailed modelling and analysis of a switched inductor (SI)-based improved single-ended primary inductor converter (SEPIC) has been presented. To increase the gain of conventional SEPIC converter, input and output side inductors are replaced with SI structures. Design and stability analysis for continuous conduction mode operation of the proposed SI-SEPIC converter has also been presented in this paper. State space averaging technique is used to model the converter and carry out the stability analysis. Performance and stability analysis of closed loop configuration is predicted by observing the open loop behaviour using Nyquist diagram and Nichols chart. System was found to stable and critically damped.

MODELLING AND SIMULATION OF ANFISBASED MPPT FOR PV SYSTEM WITH MODIFIED SEPIC CONVERTER

This paper presents modelling and simulation of artificial neuro-fuzzy inference system (ANFIS)-based maximum power point tracking (MPPT) algorithm for PV system with modified SEPIC converter. The conventional existing MPPT methods are having major drawbacks of high oscillations at maximum power point and low efficiency due to uncertain nature of solar radiation and temperature. These mentioned problems can be solved by the proposed adaptive (ANFIS)-based MPPT. The proposed work involves ANFIS and modified single ended primary inductor converter (SEPIC) to extract maximum power from PV panel. The results obtained from proposed methodology are compared with other MPPT algorithms such as perturb and observe (P&O), incremental conductance (INC) and radial basis function network (RBFN). The improvement in voltage rating of modified SEPIC is compared with conventional SEPIC converter. The result confirms the superiority of the proposed system.

Power Factor Correction of the Enhanced SEPIC Converter Using a New Control Methodology

In the paper, an enhanced single-ended primary inductance converter (SEPIC) is proposed with BLDC motor drive. The enhanced SEPIC converter is designed with the switched inductor and their control topology is analyzed with the fractional order proportional-integral-derivative (FOPID) controller with ant-lion optimiser (ALO) algorithm. The enhanced control topology of SEPIC with BLDCM is utilised to done the power factor correction and to mitigate PQ issues. In the controller topology, the speed of the BLDCM is analyzed with the FOPID controller and generated the control pulses for the optimal operations. The proposed enhanced SEPIC converter-based motor drive is implemented in the MATLAB/Simulink platform and developed the converter performances. In order to prove the effectiveness of the proposed method, this is tested with the various speeds of BLDCM drive system. The proposed method is compared with PID controller topology.

Photovoltaic System with SEPIC Converter Controlled by the Fuzzy Logic

<span lang="EN-US">In this work, a fuzzy logic controller is used to control the output voltage of a photovoltaic system with a DC-DC converter; type Single Ended Primary Inductor Converter (SEPIC). The system is designed for 210 W solar PV (SCHOTT 210) panel and to feed an average demand of 78 W. This system includes solar panels, SEPIC converter and fuzzy logic controller. The SEPIC converter provides a constant DC bus voltage and its duty cycle controlled by the fuzzy logic controller which is needed to improve PV panel’s utilization efficiency. A fuzzy logic controller (FLC) is also used to generate the PWM signal for the SEPIC converter. </span>

Performance of solar photovoltaic array fed water pumping system utilizing switched reluctance motor

This paper discusses the design and performance analysis of a solar photovoltaic (SPV) array fed water pumping system utilizing a special class of highly rugged machine with simple drive system called switched reluctance motor (SRM) drive. The proposed method of water pumping system also provides the cost effective and highly reliable solution for solar water pumping system. A unique approach of variable DC link voltage operation of SRM drive with electronic commutation for switches of mid-point converter is used with the elimination of voltage and current sensor in the motor side results in reduction in cost and losses of the system. A DC-DC single-ended primary-inductor converter (SEPIC) is used to achieve maximum power from SPV array. The characteristic of providing output voltage with no polarity reversal and having features like minimal active components and low noise operation makes SEPIC suitable for solar water pumping. The water pump with a SRM motor is used in the proposed system because of its similar operational characteristics compared to SPV generator.Keywords: SPV Array, MPPT, SEPIC converter, Soft starting, SRM, Centrifugal water pump

Robust tracking controller for SEPIC drivers

The non-minimum phase, non-linear nature of the SEPIC (single-ended primary inductor converter) makes it very difficult to get robust operating conditions under load variations. Sliding-mode control method is utilised to design a robust controller for tracking control of SEPIC converters for various applications. The implementation of the method is illustrated with the use pulse-width modulation comparators in the control loop to preclude the risk of modulator saturation and to ease the operations. The performance of the SEPIC converter is investigated through numerical simulation and analogue electronics implementation to show the validity, robustness and feasibility of the proposed controller.

A Photovoltaic-Based SEPIC Converter with Dual-Fuzzy Maximum Power Point Tracking for Optimal Buck and Boost Operations

In this paper, a photovoltaic (PV)-based single ended primary-inductor converter (SEPIC) is developed with introduction of dual-fuzzy logic controller (FLC) maximum power point tracking (MPPT) algorithm. Separate FLC parts, for the first time used for MPPT, are configured for optimal operations of both buck and boost operations. During buck operation, a high overshoot voltage exists, and during boost operation, an undershoot voltage occurs, both during the initial rising period. Definitely, a single-FLC MPPT could not be able to minimize both problems, which on the other hand can be handled by the proposed MPPT algorithm. For evaluation purposes, buck operation has been conducted during high irradiance, while during low irradiance, boost operation has been conducted. The dual-FLC MPPT with SEPIC was simulated in MATLAB-Simulink, and further a laboratory prototype was implemented with a TMS320F28335 eZdsp board. Both simulation and experimental results and comparison analysis (with the single-FLC MPPT) have been presented. From the results and analysis, the dual-FLC MPPT performs better than the single-FLC MPPT in terms of faster response time, lower overshoot and undershoot, and further significant reduction of power losses.

RBFN based MPPT algorithm for PV system with high step up converter

This paper proposes a neural network (NN) based maximum power point tracking (MPPT) algorithm for photovoltaic (PV) system with a high step–up converter design. The proposed methodology uses Radial Basis Function Network (RBFN) in NN algorithm for MPPT and the results are compared with classical perturb and observe (P&O) method and incremental conductance (INC) method. Also, to improve the voltage rating, a new modified Single Ended Primary Inductor Converter (SEPIC) is proposed and the results are validated with boost and SEPIC converter. The performance of the proposed algorithm is verified for various irradiance and temperature conditions.

A Unique SEPIC converter based Power Factor Correction method with a DCM Detection Technique

This paper presents a unique Single-Ended Primary Inductor Converter (SEPIC) based power factor correction method with discontinuous conduction mode detection. The SEPIC power factor correction (PFC) converter with the advent of digital control, powerful control techniques are used to achieve low-harmonic input current. An analog SEPIC based PFC converter is modified into a digitally controlled equivalent; thus provides flexibility for further implementations. The voltage and current sensing circuit design, compensator topology, the critical interrupt service routines, and the Digital Signal Processor (DSP) control is presented. The proposed SEPIC converter is contributes with a Discontinuous Conduction Mode (DCM) detection method using DSP for the purpose of power factor correction close to unity. The proposed detection technique has easy computation steps, and requires very small or almost null modification in existing SEPIC based PFC converters using DSP control techniques. The SEPIC-PFC converter analyse the effectiveness of the proposed detection approach over traditional detection techniques for power quality improvements. A new adaptive Mixed Conduction Mode (MCM) control technique is applies in the proposed SEPIC converter to realize optimal power factor and reduced total harmonic distortion contents in the output over a conventional controllers.

Fuzzy Logic Control of a SEPIC Converter for a Photovoltaic System

In this work, a fuzzy logic controller is used to control the output voltage of a photovoltaic system with a DC-DC converter; type Single Ended Primary Inductor Converter (SEPIC). The system is designed for 210 W solar PV (SCHOTT 210) panel and to feed an average demand of 78 W (24V). This system includes solar panels, SEPIC converter and fuzzy logic controller. The SEPIC converter provides a constant DC bus voltage and its duty cycle controlled by the fuzzy logic controller which is needed to improve PV panel’s utilization efficiency. A fuzzy logic controller (FLC) is also used to generate the PWM signal for the SEPIC converter.

Dual-Fuzzy MPPT in Photovoltaic-DC Analysis for Dual-Load Operation with SEPIC Converter

In this paper, dual-fuzzy based maximum power point tracking (MPPT) is proposed for standalone photovoltaic (PV) system, working for dual-load operation. The proposed MPPT consists of two different fuzzy logic controllers (FLCs) to support operation of single ended primary-inductor converter (SEPIC) in buck and boost conditions, by depending on irradiance conditions. To realize dual-operation of SEPIC, dual-load approach has been applied by selecting suitable load resistance, which could achieve maximum power point (MPP) with specific irradiance and duty cycle. Then, relationship between irradiance, load resistance and duty cycle has been discussed in details. The dual-fuzzy based MPPT together with PV module of Kyocera KD210GH-2PU connected to SEPIC was simulated in MATLAB-Simulink, and further the laboratory prototype with TMS320F28335 eZdsp board was implemented. Each load was connected to direct current (DC) supply to ensure continuity of the supply to both loads. Both simulation and experimental results and comparison analysis (with P&O) have been presented. From the results and analysis, dual-fuzzy based MPPT with dual loads shows that by switching from PV to DC, there is no change in output voltage, but during the switching from DC to PV, there are significant changes that can be noticed according to the irradiances.

Distributed PV Power Extraction Based on a Modified Interleaved SEPIC for Nonuniform Irradiation Conditions

Nonuniform irradiation of a photovoltaic (PV) source, consisting of series-connected modules with bypass diodes, results in multiple peaks in the power–voltage characteristics. This makes the maximum power point tracking (MPPT) difficult because the conventional MPPT algorithms can only deal with single power peak characteristics. This paper proposes a novel distributed MPPT (DMPPT) scheme based on an interleaved single-ended primary inductor converter (SEPIC) converter configuration for compensating the mismatch in characteristics of series-connected PV modules. The proposed scheme obviates the need for bypass diodes across the modules, resulting in single-peak power–voltage characteristics. The proposed DMPPT circuit is derived from an interleaved SEPIC converter that works on the “return energy” concept. The proposed configuration equalizes the voltages across PV modules of the string, resulting in their operating close to its maximum power point. Discontinuous conduction mode of operation is implemented, obviating the voltage-sensing requirements across modules, eliminating the reverse recovery loss of diodes and the turn-on loss of the main switch. The proposed DMPPT scheme uses a simple circuit with reduced control complexity and needs only a few passive elements and only one switching device, compared with the existing DMPPT schemes. The theoretical claims are validated with simulations and extensive hardware experiments.

High Gain Multi Level Dual Load SEPIC Converter for Incremental Conductance MPPT

The studies on the photovoltaic system are extensively increasing because of a large, secure, essentially exhaustible and broadly available resource as a future energy supply. However, the output power induced in the photovoltaic modules is influenced by an intensity of solar cell radiation, temperature of the solar cells and so on. Therefore, to maximize the efficiency of the renewable energy system, it is necessary to track the maximum power point of the input source. This paper presents the modeling and simulation of incremental conductance (IncCond) Maximum Power Point Tracking (MPPT) using Multi level Single Ended Primary Inductance Converter (SEPIC) converter and compared its performance with self lift SEPIC converter. The solar panel model is developed using the basic circuit equations of photovoltaic cell. The MPP of a solar panel varies with irradiation and temperature. The IncCond algorithm is used to track the maximum power from the solar panel. The unregulated voltage from the panel will be regulated by using the Multi level SEPIC at the same time it can also supply the medium voltage and high voltage loads. The efficiency of the Multi level SEPIC converter over the self lift sepic converter has been tested by using Matlab/Simulink