SINGLE STAGE LOW FREQUENCY ELECTRONIC BALLAST FOR HID LAMPS

The paper presents a single-stage high-power-factor electronic ballast for metal halide lamps. The proposed ballast integrates a buck-boost converter, a buck converter and a full-bridge inverter into a single power conversion circuit. The buck-boost converter served as a power factor corrector (PFC) is designed to operate at discontinuous conduction mode (DCM) to achieve nearly a unity power factor at the input line. By adjusting the duty-ratio of the active switches of the PFC, the lamp power is remained at rated value for universal input voltage ranged from 90 Vrms to 264 Vrms. The four active switches of the full-bridge inverter, an inductor and a capacitor form a bidirectional buck converter which supplies a low frequency square-wave currentfor the lamp at to avoid the lamp from happing acoustic resonance. The circuit operation is analyzed in detail to derive the design equations. A prototype electronic ballast for a 70 W metal halide lamp is built and tested

Buck-boost single-stage microinverter for building integrated photovoltaic systems

Microinverters for Building Integrated Photovoltaic (BIPV) systems must have had a small number of components, be efficient, and be reliable. In this context, a single-phase Buck-Boost Single-stage Microinverter (BBSM) for grid-connected BIPV systems is presented. The concept of topology is extracted from the buck-boost converter. The leakage current in the system is kept under control. It uses an optimal number of active and passive components to function at a high-efficiency level. The suggested topology provides a high level of reliability due to the absence of shoot-through problems. To validate the findings, a simulation in combination with an experimental system for a 70 W system is developed with the design approach. The efficiency of the microinverter, total harmonic distortion of the grid current are measured as 96.4% and 4.09% respectively. Finally, a comparison study has indicated the advantages and disadvantages of the suggested inverter

Power Quality Enhancement in Hybrid Photovoltaic-Battery System based on three–Level Inverter associated with DC bus Voltage Control

This modest paper presents a study on the energy quality produced by a hybrid system consisting of a Photovoltaic (PV) power source connected to a battery. A three-level inverter was used in the system studied for the purpose of improving the quality of energy injected into the grid and decreasing the Total Harmonic Distortion (THD). A Maximum Power Point Tracking (MPPT) algorithm based on a Fuzzy Logic Controller (FLC) is used for the purpose of ensuring optimal production of photovoltaic energy. In addition, another FLC controller is used to ensure DC bus stabilization. The considered system was implemented in the Matlab /SimPowerSystems environment. The results show the effectiveness of the proposed inverter at three levels in improving the quality of energy injected from the system into the grid.Peer reviewedFinal Published versio

Buck-boost dc voltage regulator

Circuit provides voltage regulation through a wide range of operating frequencies without intervals of high power dissipation

ASDTIC control and standardized interface circuits applied to buck, parallel and buck-boost dc to dc power converters

Versatile standardized pulse modulation nondissipatively regulated control signal processing circuits were applied to three most commonly used dc to dc power converter configurations: (1) the series switching buck-regulator, (2) the pulse modulated parallel inverter, and (3) the buck-boost converter. The unique control concept and the commonality of control functions for all switching regulators have resulted in improved static and dynamic performance and control circuit standardization. New power-circuit technology was also applied to enhance reliability and to achieve optimum weight and efficiency

Transformer‐Based Z‐Source Inverter with MVDC Link

Z‐source inverters have attracted considerable attention in renewable energy systems like photovoltaic (PV) systems due to advantages such as buck–boost power conversion in single stage, shoot-through capability, and wide range of input voltage regulation. Transformer-Based Z-source inverters (TransZSI) based on magnetically coupled inductors and reduced number of passive components can be used to improve the boost capacity of these inverters, and to increase the voltage levels. Medium voltage DC (MVDC) is being used more and more in distribution grids and renewable energy systems. This paper presents a transZ-source inverter with MVDC link where renewable energy systems and energy storage systems can be integrated. The active and reactive powers and DC voltage are controlled by acting on the modulation index and shoot-through duty cycle of the converter. The trans-Z-source inverter is evaluated under different operating conditions to illustrate its suitable operation. © 2022, European Association for the Development of Renewable Energy, Environment and Power Quality (EA4EPQ). All rights reserved

Mariner Mars power system optimization study Interim report, 4 Mar. - 31 May 1968

Optimum Mariner spacecraft solar power system model

HA 컨버터를 응용한 AC-DC 및 DC-AC 전력 변환

학위논문 (박사)-- 서울대학교 대학원 : 전기공학부, 2013. 2. 조보형.This dissertation proposes a new topology H-bridge converter with additional switch legs (HA converter). The proposed topology has simple circuit structure with expandability and flexibility. With six semiconductor devices and single inductor, the topology is capable of operating as buck, boost, and buck-boost converter. Theoretically, it demonstrates low common mode current and electromagnetic interference (EMI) by solidly connecting grounds of input and output terminals. The proposed topology is advantageous not only in grid-connected power conversion application but also in stand-alone power system such as electric vehicle, because these systems include large parasitic capacitances and are prone to high common mode EMI due to the wide mechanical structure of the conductor. Among many offspring circuits of the HA converter, a boost-buck-boost (B3) rectifier for off-line power supply with active power factor correction and a buck-buck-boost (B3) inverter for grid-connected photovoltaic system are proposed as two practical examples. Principle of operations, dedicated control algorithms, and filters for the new circuits are analyzed and designed in detail. Experimental results based on the laboratory prototype hardware prove that the proposed circuits outperform their conventional counterparts by showing low common mode noise and comparable efficiency.Abstract............................i Contents...........................ii List of Figures....................iv List of Tables......................x 1. Introduction.....................1 1.1. Motivations and Backgrounds....1 1.2. Objectives.....................2 1.3. Dissertation Outlines..........4 2. H-bridge Converter with Additional Switch Legs (HA Converter)......................7 2.1. Review of Common Mode EMI......7 2.1.1. In Off-line AC-DC Rectifier.11 2.1.2. In Grid-connected DC-AC PV Inverter...........................16 2.2. Topology Derivation...........24 2.2.1. Dual H-bridges..............29 2.2.2. HA Converter................31 2.3. Feature of HA Converter.......34 3. B3 Rectifier for AC-DC Conversion.........................40 3.1. Advantage of B3 Rectifier.....40 3.2. Operation.....................43 3.3. Control.......................45 3.3.1. Power Imbalance in a Line Cycle..............................47 3.3.2. Inductor Current Reference Calculation........................51 3.3.3. Compensator Design..........56 3.4. Differential Input Filter Design.............................67 3.5. Experiments...................75 3.5.1. Implementations.............75 3.5.2. Results and Discussions.....81 4. B3 Inverter for DC-AC Conversion.........................88 4.1. Advantage of B3 Inverter...........................88 4.2. Operation.....................91 4.3. Control.......................93 4.3.1. Inductor Current Reference Calculation........................93 4.3.2. Compensator Design..........98 4.4. Differential Output Filter Design............................104 4.5. Experiments..................111 4.5.1. Implementations............111 4.5.2. Results and Discussions....117 5. Flexibility of HA Converter.........................125 6. Conclusion and Further Works...134 Appendix..........................137 A.1. Correction Factor of B3 Rectifier in Small Signal Model.............................137 A.2. Input Impedances of Boost and Buck-boost Converter.........................139 A.3. Loss Estimation of B3 Rectifier Switches..........................144 A.4. H5 and HERIC Inverter Operations........................153 References........................160 국문 초록.........................168 감사의 글.........................169Docto

Mars spacecraft power system development Interim report

Modified Mariner power system design for Mars mission