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In this paper, a new phase locked loop (PLL) is proposed for both single and three phase systems. A Phase detection is the most challenging issue in single phase PLLs. Due to the benefits of vector multiplier phase detector, new orthogonal signal estimator is proposed with the help of simple VCO to make the vector multiplier PD usable for single phase PLLs. The proposed PLL shows fast dynamic response and robust performance against input signal distortion such as harmonic polluted and amplitude collapse. Also, it has a simple structure and less computational burden which make it easy for fully digital implementation. The proposed PLL is implemented digitally based on a TMS320F28335 developed board. To fully evaluate the performance of proposed PLL, a 4 kW single phase grid connected converter is also provided. All the simulation and experimental results verify the effectiveness and superior performance of the proposed PLL. [ABSTRACT FROM AUTHOR]

In this paper, current-mode boundary conduction mode (BCM) of a high-efficiency LED driver with high power factor, utilizing low-voltage film capacitors, is presented, and its theoretical design and considerations are discussed. The 1.5-stage driver consists of a forward-flyback and buck converter. Higher efficiency was reached using the reduced redundant power processing approach. Most of the processed energy is transferred to the output through flyback, while the rest removes the low harmonic ripple in the output current through the forward-buck path. An acceptable amount of odd harmonics is injected into the input current by using current-mode BCM control method, further reducing bus capacitance. To validate these principles, a laboratory prototype has been built and experimental results of a high-current 85 W (29.5 V/2.9 A) lamp with 50 Hz, 185–255 V power supply are provided. The results show that output current ripple is low, and the input current harmonics are within the standard regulations. [ABSTRACT FROM AUTHOR]

This paper proposes a novel nonisolated single-input dual-output three-level dc–dc converter (SIDO-TLC) appropriate for medium- and high-voltage applications. The SIDO-TLC is an integration of the three-level buck and boost converters, whose output voltages are regulated simultaneously. Reducing voltage stress across semiconductor devices, improving efficiency, and reducing inductors size are among the main merits of the new topology. Moreover, due to the considerably reduced volume of the step-down filter capacitor, a small film capacitor can be used instead, whose advantages are lower equivalent series resistance and a longer lifespan. A closed-loop control system has been designed based on a small-signal model derivation in order to regulate the output voltages along with the capacitors’ voltage balancing. In order to verify the theoretical and simulation results, a 300-W prototype was built and experimented. The results prove the aforementioned advantages of the SIDO-TLC, and the high effectiveness of the balancing control strategy. Furthermore, the converter shows very good stability, even under simultaneous step changes of the loads and input voltage. [ABSTRACT FROM AUTHOR]

In this paper, a stationary-frame, single-loop controller for three-phase standalone inverter supplying nonlinear loads has been derived from synchronous reference frame proportional-integral multiloop controller. In this method, load voltage harmonics are eliminated by a single loop and only one control variable. The proposed method has several advantages such as lack of Park transformation and requires tuning only one control parameter. It can also be implemented with less computational burden, less complexity, and easier tuning, compared to conventional proportional-integral multiloop controller. Experimental results with laboratory prototype under linear and nonlinear load conditions validate the proposed method. [ABSTRACT FROM AUTHOR]