Power factor corrected AC-DC converter topologies have been of research interest for DC power supplies. The main goal of this work is to improve power quality at the supply side and maintain constant DC voltage at the output side by designing a Modified Bridge Less Positive Output Luo (MBLPOL) power factor correction (PFC) converter. Discontinuous conduction mode is also possible for input PFC with a small filter at the source side. In order to regulate the DC load voltage for various loads and supply voltage conditions, a feedback control circuit with a single voltage sensor is proposed for the PFC converter. A prototype of 100 W, 48 V, AC-DC MBLPOL converter is designed and tested. Proper design of controller for the converter guarantees the excellent performance and the same is validated with the help of simulation and hardware results. The proposed MBLPOL converter is tested for DC load voltage regulation for various load power and supply voltage variations. The experimental study shows supply current total harmonic distortion of 1.24% at rated load while maintaining unity power factor.
-This paper presents the design of closed loop controllers operating a single-phase AC-DC three-level converter for improving power quality at AC mains. Closed loop inhibits outer voltage controller and inner current controller. Simulations of three level converter with three different voltage and current controller combinations such as PI-Hysteresis, Fuzzy-Hysteresis and Fuzzy tuned PIHysteresis are carried out in MATLAB/Simulink. Performance parameters such as input power factor and source current total harmonic distortion (THD) are considered for comparison of the three controller combinations. The fuzzy-tuned PI voltage controller with hysteresis current controller combination provides a better result, with a source-current THD of 0.93% and unity power factor without any source side filter for the three level converter. For load variations of 25% to 100%, a THD of less than 5% is obtained with a maximum value of only 1.67%. Finally, the fuzzy-tuned PI voltage with hysteresis controller combination is implemented in a Xilinx Spartan-6 XC6SLX25 FPGA board for experimental validation of power quality enhancement. A prototype 100 W, 0-24-48 V as output converter is considered for the testing of controller performance. A source-current THD of 1.351% is obtained in the experimental study with a power factor near unity. For load variations of 25% to 100%, the THD is found to be less than 5%, with a maximum value of only 2.698% in the experimental setup which matches with the simulation results.
Background: A conventional front-end rectifier causes line current distortion and reduces the power factor, which result in lowering power quality for Light Emitting Diode (LED) drive system. Hence, this paper projects the design, simulation and comparison of novel PI tuned by the fuzzy logic controller with the conventional PI controller for modified SEPIC rectifier to produce the required load voltage along with supply-side unity power factor and less distorted supply current with limited harmonic content for LED lighting in healthcare applications. A prototype of 100W, 48V LED driver was developed for testing the performance of the controller. Methods: This paper presents the modified SEPIC LED driver with PI integrated fuzzy and classical PI for controlling voltage. For controlling source current, classical PI is chosen. Both are equipped with the modified SEPIC rectifier. Both conventional PI control and novel fuzzy tuned performances were compared. Results: The proposed control topology operated modified SEPIC rectifier was analyzed and the corresponding power factor and THD were measured. The operational evaluation of the proposed LED driver using fuzzy tuned-PI/PI controller combinations for different output power is provided in Table 2. Sustained regulated DC voltage of 48V was achieved even when the load resistance varied within a specific range. Power factor of 0.9995, which is close to unity, was also achieved. The relative analysis was made with conventional PI and trendy PI integrated FLC controller which is provided in Table 3. The usage of PI integrated fuzzy logic controller minimized the peak overshoot to be around 1.3% and rise time of 0.5s which are lower when compared to the conventional PI controller. With reference to Fig. (8a), the source current THD of the conventional PI controller was observed to be around 7.39%. Having PI integrated FLC, THD was further reduced and for rated load, it was found to be 1.39%. The power factor of the conventional PI controller is around 0.9974. PI integrated fuzzy logic controller improved the power factor to 0.9995 with fuzzy tuned PI controller in action as shown in Fig. (8b). A prototype of 100W, 48V LED driver was developed for testing the performance of the controller. A power quality analyser was employed for measuring power factor and THD, shown in Fig. (10a). 3.633% of harmonic distortions at the source current and 0.9980% of input power factor was achieved for rated load power. 4.510% of supply current THD with 0.9931% input power factor was achieved for low load power. Conclusion: This manuscript suggests a modified single switch SEPIC LED driver for 48V output operated healthcare equipment. Simulation study of this driver shows the better performance. In order to analyze the performance, a comparative study was conducted by using the classical PI and the novel PI integrated fuzzy controller. Satisfactory results regarding enhanced quality of power, regulated load voltage, quick rise time and settling time were achieved. The source current THD has been reduced to around 1.39% which is less than 5% as per the IEEE-516 prescribed standard and the power factor has been improved to 0.9995 by implementing the fuzzy tuned PI controller. The above results favor the suggested modified SEPIC LED driver for practical healthcare applications.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.