Implementation of a Sliding Mode Controller for Single Ended Primary Inductor Converter

A novel step-up/step-down DC-DC converter with improved voltage gain characteristics is suggested in this paper. The proposed converter combines flyback and single-ended primary inductance converter (SEPIC) converters. The voltage control loop design is simplified due to the use of only a single controlled switch. It has been discussed how switch duty cycle affects voltage gain. This relationship demonstrates that the proposed converter voltage gain is improved compared with flyback and SEPIC converters. However, compared to flyback and SEPIC converters, it has a higher voltage gain at any given duty cycle. The proposed converter operation is thoroughly discussed, the associated equations are derived, and its parameters are expertly designed. Moreover, it is designed to supply a DC load of 2.5 kW, 500 V, and 5 A. The proposed converter efficiency exceeds 84% under rated load conditions. Additionally, it is also presented as an adapter for electric vehicles. The waveforms associated with the simulation of the converter across the universal line voltage of 110-260 Vrms are shown. At both line voltages, the total harmonics distortions (THDs) of the line current are 17.12% and 27.26%, respectively. MATLAB/Simulink is utilized for validation in order to validate the topology for different applications.

SEPIC (Single Ended Primary Inductance Converter) is a dc-dc converter which can provide an output voltage either greater than or less than the input voltage. Basically it is similar to a buck-boost converter. The output voltage polarity of a SEPIC is non-inverted whereas the output voltage polarity is inverted in a buck-boost converter. SEPIC converters are widely used in battery operated equipment, power supplies for laptops and computers, power factor correction etc. Rapid development of computing technologies lead to great use of simulation tools for the planning and design of electrical systems. Nowadays complex electrical systems can be simulated with less time. There are mainly two types of simulations. One is offline simulation and other is real time simulation. In real time simulation both physical time and simulation time are same. Real time simulators are extensively used in many engineering fields. Statistical power grid protection tests, aircraft design and simulation, motor drive controller design methods and space robot integration are a few examples of real-time simulator technology applications. In this paper an average model of the SEPIC is derived at first. Then an offline simulation and real time simulation of SEPIC using miniature full spectrum simulator is explained.

Simulation and analyses of SEPIC converter using linear PID and fuzzy logic controller

Due to rising environmental challenges and complicated emission regulations, electric vehicles have been seen as an alternative to traditional transportation. Modern electric vehicles use electronic circuits powered by electrical energy (PECs). DC to DC converters and DC to AC inverters are both classed as PECs. DC to AC inverter: It delivers utility power while also driving electric motors; the DC to DC converter serves as a source of low voltage utility electricity. DC to DC converters are categorised according to application requirements. In order to charge a high-power electric load, an increase in output is needed. It is because of this that it uses the SEPIC converter. DC-DC converter designates the single-ended primary-inductor converter (SEPIC). The electrical potential may be any value, such as less than, equal to, or greater than the input voltage. Duty cycle of the control transistor governs the SEPIC output. In SEPIC, voltage conversion is accomplished by transferring energy between inductors and capacitors. SEPIC boost converter relates to buck-boost converter modification. Both are comparable. The SEPIC converter has a few benefits. They are non-inverted input- same polarity of input and output voltage, between output and input, energy is linked using a series capacitor- to a short circuit output, producing greater responsiveness, genuine shutdown is possible- output goes to 0V if switch is off. This converter is simple to control while operating in CCM mode. Because both switches use the same gating pulse, the duty cycle may be adjusted to obtain a broad range of output voltage. In terms of number of components, diode and switch voltage stress, and voltage gain, recent non-coupled inductor converters are compared to the proposed converter. With regard to output voltage, the suggested converter produces a lower proportion of voltage stress on switches. When compared to existing converters, the suggested converter produces a high voltage gain with fewer components.

This paper provides a modified single-ended primary inductor converter (SEPIC) with an asymmetrical switched inductor super lift cell (ASISLC) for renewable energy applications. Solar, fuel cells, and so on, provide low output voltage, which is not sufficient for high voltage dc grid or dc loads. Therefore, the existence of a high gain DC-DC converter is mandatory. The proposed converter provides high gain, high efficiency, and less voltage stress at a low duty cycle. The proposed converter incorporates switched inductor together with a super lift cell. The super lift cell has a charge pump capacitor is connected in an asymmetrical fashion. The proposed converter offers continuous current at the input together with the above-mentioned advantages. This paper explains the operation of the ASISLC SEPIC converter in continuous conduction mode (CCM) and discontinuous conduction mode (DCM). The operating principle, theoretical analysis, design process, and comparison of the suggested converters with converters from the literature that use similar operating principles are all discussed in this paper. A MATLAB simulation is done and their results are provided. Finally, a hardware prototype for 200W, 50 kHz switching frequency is built and their results are validated to authenticate the effectiveness of the proposed converter.

<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>

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.

This paper proposes a capacitor switching logic for a multi input Single Ended Primary Inductance Converter (SEPIC) with efficient Maximum Power Point Tracking (MPPT) scheme for multiple non aligned solar panels. The proposed scheme is an improvement of time division multiplexing control of multi input converters for low power solar energy harvesters. In the proposed design, the capacitor switching logic gives the flexibility of selecting panels on demand providing additional advantage of isolation. For better accuracy an efficient algorithm has been implemented for determining MPPT. The MPPT is practically determined in each cycle when the corresponding capacitor is connected to converter. Using SEPIC converter at the output provides a constant 15V for charging the battery for solar panel voltage range from 8V to 25V. The design improvements will bring increased efficiency for medium power solar systems.

Regularization in power production increasing global need of power the renewable energy resource brings more attention. These resources are responsible for deducing carbon dioxide emission during burning coal, deforestation due to extension and installation of hydroelectric power plants, ozone layer depletion. Among hydro, tidal, wind, solar, geothermal; solar is preferred due to affordability and availability, compact in structure. The structure of Single ended primary inductor converter (SEPIC) interfaced with renewable energy resource to obtain high voltage gain is proposed in this paper. The SEPIC converter has several benefits such as low voltage distortion, reduction in noise level, low switching stress, and continuous input current. Also, high voltage gain and input current continuity make the presented converter suitable for renewable energy sources. The modified structure provides high gain ratio with a single power semiconducting switch. With less number of active and passive components enrolled within proposed system deduce capital cost and improves efficiency. The system efficiency is also analyzed with voltage gain under continuous and discontinuous conduction mode. Depending upon the reactive component’s voltage-current ratio of active and passive components is chosen respectively. The circuit topology is verified is through MATLAB software and experimental analysis.

The photovoltaic (PV) stand-alone system requires a battery charger for energy storage. This paper presents the modeling and controller design of the PV charger system implemented with the single-ended primary inductance converter (SEPIC). The designed SEPIC employs the peak-current-mode control with the current command generated from the input PV voltage regulating loop, where the voltage command is determined by both the PV module maximum power point tracking (MPPT) control loop and the battery charging loop. The control objective is to balance the power flow from the PV module to the battery and the load such that the PV power is utilized effectively and the battery is charged with three charging stages. This paper gives a detailed modeling of the SEPIC with the PV module input and peak-current-mode control first. Accordingly, the PV voltage controller, as well as the adaptive MPPT controller, is designed. An 80-W prototype system is built. The effectiveness of the proposed methods is proved with some simulation and experimental results.

The integration of a Single-Ended Primary-Inductor Converter (SEPIC) combined with a Genetic Algorithm (GA) characterizes a significant improvement in the domain of efficiency and overall performance of photovoltaic (PV) systems. This novel approach involves the SEPIC converter which has the ability to deliver a high-efficiency conversion mechanism which helps in enabling the optimization of the power extraction from solar panels. This can function in both step-up and step-down modes which helps in making it more suitable for photovoltaic applications where the panel output can vary generally due to changes in sunlight intensity and temperature. The Genetic Algorithm, on the other hand, is a search heuristic that mimics the process of natural selection to identify optimal solutions. When applied to the SEPIC converter in PV systems, the GA continuously adjusts the converter's parameters to find the optimal operating point even under fluctuating varied environmental conditions. This safeguards maximum power output from the solar panels by dynamically adapting to changes, thereby improving the overall energy harvesting efficiency. This combination of the SEPIC converter and Genetic Algorithm leverages the strengths of both: the SEPIC converter's flexibility in handling varying input voltages and the GA's ability to find the optimal solution in a complex search space. As a result, the energy harvesting process in photovoltaic systems becomes more robust, efficient, and capable of delivering improved performance, ultimately leading to higher electricity generation from solar energy sources. This approach not only enhances the sustainability of power systems but also contributes to the reduction of dependency on fossil fuels by optimizing renewable energy sources.

In this paper, an adaptive nonlinear method is proposed for both Maximum Power Point Traking Control and output voltage regulation of a Single-Ended Primary Inductance Converter (SEPIC). The main objective of this adaptive synergetic controller is to maintain a constant switching frequency of the converter and to stabilize the output voltage under uncertain weather conditions in real time. A hybrid control scheme has been derived and a Radial Basis function neural network used for approximation of unmeasurable or unmeasured variables. The effect of the controller to provide a maximum power transfer from PV side to SEPIC converter under unpredictable weather conditions and load variations has been verified through simulations. The stability of the close-loop system is insured by Lyapunov’s theory and the proposed algorithm gives good results compared to the Sliding Mode Controller used in the same context.

In modern time, LED (Light Emitting Diode) bulbs are being most preferred over incandescent bulbs, compact fluorescent lamps (CFL) and other lighting equipments because of their high luminous efficacy, long life, robustness, small size and so on. This paper covers the study, design and simulation of 30 Watt LED bulb driver circuit in MATLAB-Simulink environment. SEPIC (Single Ended Primary Inductor Converter) converter has been used as PFC (Power Factor Corrected) converter for shaping of input ac current and operates in CCM (Continuous Conduction Mode). For the study of LED bulb driver circuit the simulation results have been shown. The power quality parameters like power factor (PF), total harmonic distortion of input ac current (THD i ), crest factor (CF) have been shown in the table for a wide range of in input ac voltage 85– 265V with frequency of 50 Hz.

The basic operation of a solar cell, module or photovoltaic generator under different irradiation and temperature conditions is characterized by its I-V characteristic curve. Only the experimental measurement of the I-V curve allows us to know with precision the electrical parameters of a photovoltaic cell, module or array. This measure provides very relevant information for the design, installation and maintenance of photovoltaic systems. Currently, the I-V characteristic curve is obtained by connecting a variable charge to the panel terminals in order to achieve that the current of the terminals ranges from zero to the short circuit current. In this paper we propose a new experimental way to measure this characteristic curve by using Buck-Boost-Derived DC-DC converters. It has been proved that the optimal topologies for this purpose are the SEPIC (Single-Ended Primary Inductance Converter) and Cuk converters. The theoretical analysis performed has been validated by means of simulation and experimentally. Additionally, a comparison between three known conventional methods and the proposed one is provided.

In this paper, a (PF) Power factor correction and power quality (PQ) improvement based BLDC motor drive proposed. Normally the permanent magnet BLDC motor drive connected with the diode bridge rectifier and high value of the capacitor due to which poor power factor and higher THD (Total harmonic distortion) value at the input side To overcome this difficulty SEPIC (Single-ended primary inductance converter) converter use to optimize the PF and THD value. The converter operates in discontinuous conduction mode to get the desired result. This scheme also used for speed control of BLDC motor by controlling the VSI (voltage source inverter) feeding the BLDC drive.