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The analysis and design of a dimmable electronic ballast based on the class E amplifier and fed from solar cells with 12V backup batteries is described. The class E amplifier uses a capacitive impedance inverter as resonant tank and one diode antiparallel with the switch; these elements allow implementation of a dimming feature for the ballast and ignition of the lamp while maintaining zero voltage commutations in the switch. The designed electronic ballast drives a 21W lamp and operates at a switching frequency of 370kHz. Dimming is implemented using an SG3524 in a voltage-controlled oscillator fashion. [ABSTRACT FROM AUTHOR]

Presents information on a paper which has a novel approach on an integrated battery charger/discharger. What does this integrated battery charger/discharger offer; Description of battery; What is the battery used for.

This paper presents a different Finite Control Set – Model Predictive Control (FCS-MPC) for grid-connected three-phase bidirectional power inverters. These are typically used in dc or ac renewable-based microgrids (MGs), where bidirectional operation and fast dynamic response is required. The bidirectional grid-connected inverters are an essential part of MG, which inject energy into the ac grid or demand energy from it. The dynamic behavior of the system is a major concern since the current can suddenly change depending on the hierarchical controller. This paper proposes a different cost function using sliding mode theory, which offers a good dynamic response, reduced computational burden, and a parameter-free control model. The operation principle of the proposed controller is given and evaluated using a Hardware-In-the-Loop (HIL) system, but also experimentally with a 1kW laboratory prototype. The final results demonstrate the advantages of using this approach in grid-connected three-phase bidirectional power inverters in terms of dynamic response and reduced computational burden, making this solution technically attractive and viable. [ABSTRACT FROM AUTHOR]

In recent years, several ac/dc converters have been presented in order to meet the power quality regulations, while maintaining the lowest number of components with the purpose of minimizing the cost and complexity; for this purpose the active input current shaping technique was proposed. In this paper a new active input current shaper (AICS) is presented. Differently from the traditional series AICS, the proposed scheme connects the auxiliary output of the main converter in parallel with the rectified ac mains instead of the series connection. The proposed parallel scheme demands a current with a low harmonic content where the standard specifications are fulfilled. The operation, simulation, and experimental results of the proposed scheme are presented. [ABSTRACT FROM AUTHOR]

Presents a simplified sinusoidal uninterruptible power supply (UPS) system with active power factor correction. Features of the proposed UPS system; Advantage of the system; Circuit operation of the proposed UPS system.

Although PV systems are one of the most widely used alternatives as a renewable energy source due to their well-known advantages, there are significant challenges to address related to voltage fluctuations and reverse power flow caused by high PV penetration scenarios. As a potential solution to this problem, an active power management strategy is proposed in this work using a residential cluster as a benchmark. The proposed strategy is analyzed and experimentally verified, offering a simple way to reduce the voltage fluctuations by regulating the active power delivered by the PV system, achieving also relevant functionalities for the system, such as the regulation of the DC bus voltage, maximum power point tracking (MPPT), synchronization with the grid voltage, detection of high penetration conditions, and a simple strategy for the main controller with an effective performance. The proposal system shows satisfactory results being able to maintain grid voltage fluctuations within the voltage standard specifications. [ABSTRACT FROM AUTHOR]

A three-port converter suitable for standalone applications is proposed in this paper. Each port is used for specific input or output, and its functions depend on the port; they are the renewable source, the battery set, and the output port. This proposed converter is considered for standalone operation, but it is not limited to it. Not only the system is able to deliver energy independently from each input source or in a mixed way for the output, but also the battery system may be charged from the renewable source just in case it is required. The battery port is only used when it is required; this allows increasing battery lifetime. Another important feature is that, in case of a renewable source failure, the energy is automatically demanded from the battery set, like an uninterruptible power supply. The system is able to track the maximum power of the renewable source when it is required. Operation, analysis, simulation, and experimental results are described in detail. [ABSTRACT FROM AUTHOR]

DC/AC converters are widely used in several applications; traditionally, they can be classified in two types: the voltage-source inverters (VSIs) and the current-source inverters (CSIs). Their use depends on their application; however, some of them are common for both types of converters. Another possibility for the dc/ac conversion is the multilevel configuration, and the most analyzed is the VSI. In this paper, a different multilevel CSI is proposed: the paralleled configuration. To control the converter, a different sinusoidal pulse with modulation is employed; it consists of modifying the reference signal instead of using multiple carriers. Additionally, a balancing method for the inductor currents is given. The operation, analysis, and implementation are presented; moreover, simulation and experimental results are shown. [ABSTRACT FROM AUTHOR]

An active current injection network for a three-phase rectifier is proposed. The proposed circuit uses three bidirectional switches operating at low frequency and a half-bridge inverter operating at high frequency. It also uses an inductor in order to make the current modulation. Because only 3.7% of the total power delivered to the load is processed by the injection network, the proposed converter offers high efficiency, and not only a high power factor is obtained but also the total harmonic distortion is reduced. Operation, analysis, simulation, and experimental results are shown in this paper. [ABSTRACT FROM AUTHOR]

An uninterruptible power supply (UPS) with high power factor and two conversion stages is suggested. The double- conversion configuration has three stages, but normally, only two stages are operating at the same time. The first stage of the proposed scheme integrates the power-factor-correction stage and the battery charger of the double-conversion configuration, obtaining a two-stage UPS. The second stage is based on the theory of inverter with boosting capabilities. The battery set has not only been completely isolated, but it has also been charged with a small change at the controller set point; these particular characteristics facilitate the system maintenance and simplify its operation. Additionally, the battery-set voltage is low, reducing the weight and size. The converter operation, analysis, design, and experimental results are shown. The proposed UPS approach is practical in low-power applications (⩽ 500 W). [ABSTRACT FROM AUTHOR]

In this paper, a single-stage high-power-factor high-efficiency electronic ballast for compact fluorescent lamps is presented. The proposed topology uses two voltage sources connected in series to feed the inverter ballasting the lamp, one of them consists in the rectified line voltage and the other in a dc-dc converter operating in discontinuous conduction mode. In this way, the converter processes a lower energy than the nominal power of the lamp. The proposed topology presents simplicity, high-power-factor, low current crest factor, and high efficiency. [ABSTRACT FROM AUTHOR]

Nowadays, the use of the hardware in the loop (HIL) simulation has gained popularity among researchers all over the world. One of its main applications is the simulation of power electronics converters. However, the equipment designed for this purpose is difficult to acquire for some universities or research centers, so ad-hoc solutions for the implementation of HIL simulation in low-cost hardware for power electronics converters is a novel research topic. However, the information regarding implementation is written at a high technical level and in a specific language that is not easy for non-expert users to understand. In this paper, a systematic methodology using LabVIEW software (LabVIEW 2018) for HIL simulation is shown. A fast and easy implementation of power converter topologies is obtained by means of the differential equations that define each state of the power converter. Five simple steps are considered: designing the converter, modeling the converter, solving the model using a numerical method, programming an off-line simulation of the model using fixed-point representation, and implementing the solution of the model in a Field-Programmable Gate Array (FPGA). This methodology is intended for people with no experience in the use of languages as Very High-Speed Integrated Circuit Hardware Description Language (VHDL) for Real-Time Simulation (RTS) and HIL simulation. In order to prove the methodology's effectiveness and easiness, two converters were simulated—a buck converter and a three-phase Voltage Source Inverter (VSI)—and compared with the simulation of commercial software (PSIM® v9.0) and a real power converter. [ABSTRACT FROM AUTHOR]