A Single-Stage LED Driver Based on ZCDS Class-E Current-Driven Rectifier as a PFC for Street-Lighting Applications

This paper presents a light-emitting diode (LED) driver for street-lighting applications that uses a resonant rectifier as a power-factor corrector (PFC). The PFC semistage is based on a zero-current and zero-derivative-switching (ZCDS) Class-E current-driven rectifier, and the LED driver semistage is based on a zero-voltage-switching (ZVS) Class-D LLC resonant converter that is integrated into a single-stage topology. To increase the conduction angle of the bridge-rectifier diodes current and to decrease the current harmonics that are injected in the utility line, the ZCDS Class-E rectifier is placed between the bridge-rectifier and a dc-link capacitor. The ZCDS Class-E rectifieris driven by a high-frequency current source, which is obtained from a square-wave output voltage of the ZVS Class-D LLC resonant converter using a matching network. Additionally, the proposed converter has a soft-switching characteristic that reduces switching losses and switching noise. A prototype for a 150-W LED street light has been developed and tested to evaluate the performance of the proposed approach. The proposed LED driver had a high efficiency (>91%), a high PF (>0.99), and a low total harmonic distortion (THD i <; 8%) under variation of the utility-line input voltage from 180 to 250 V rms . These experimental results demonstrate the feasibility of the proposed LED scheme

Hybridizing Technology Management and Knowledge Management to Spur Innovation: A System Dynamics Approach

The purpose of this research is to identify the drivers of innovativeness in a furniture manufacturing company. The scenario is the business environment where the hybridization of Technology Management (TM) and Knowledge Management (KM) is operative to promote innovation. The elements of the Technology Acceptance Model (TAM) and Socialization-Externalization-Internalization-Externalization (SECI) Model of KM have been modeled and used for simulation for the identification of the role played by the factors influencing the furniture design information conversion rate. The research follows the case study method to research as it draws data from a single company. Data from a multinational furniture manufacturing company that has over 10,000 products and operates in 24 countries have been used for simulation purposes. Results have shown that among the five factors that influence information conversion rate, the company should focus on correction efficiency and calculation efficiency enhancement if the aim is to maximize product and process innovations; and enhance contextualization efficiency if the priority is immediate results of innovativeness improvement. The results have also shown that about 615 innovative products and processes can be produced in six months by improving the correction efficiency to 80%. The theoretical implication of the study is in the form of a model which can be used by innovative companies to identify the critical factors that influence innovativeness, and the practical implications are in the form of suggestions to the managers of the furniture manufacturing company to enhance their innovativeness so as to gain competitive advantage in business

Optimal Operation of Distributed Generations Considering Demand Response in a Microgrid Using GWO Algorithm

The widespread penetration of distributed energy sources and theuse of load response programs, especially in a microgrid, have caused manypower system issues, such as control and operation of these networks, tobe affected. The control and operation of many small-distributed generationunits with different performance characteristics create another challenge forthe safe and efficient operation of the microgrid. In this paper, the optimumoperation of distributed generation resources and heat and power storage ina microgrid, was performed based on real-time pricing through the proposedgray wolf optimization (GWO) algorithm to reduce the energy supply costwith the microgrid. Distributed generation resources such as solar panels,diesel generators with battery storage, and boiler thermal resources withthermal storage were used in the studied microgrid. Also, a combined heatand power (CHP) unit was used to produce thermal and electrical energysimultaneously. In the simulations, in addition to the gray wolf algorithm,some optimization algorithms have also been used. Then the results of 20runs for each algorithm confirmed the high accuracy of the proposed GWOalgorithm. The results of the simulations indicated that the CHP energyresources must be managed to have a minimum cost of energy supply in themicrogrid, considering the demand response program

Optimal coordination of TCSC and PSS2B controllers in electric power systems using MOPSO multiobjective algorithm

Oscillations are an intrinsic phenomenon in interconnected power systems, leading to steady-state stability, safety decline, transmission power limitation, and electric power systems’ ineffective exploitation by developing power systems, particularly by connecting these systems to low-load lines. In addition, they affect the economic performance of the systems. In this study, PSS2B power system stabilizers and TCSC compensators are used to improve the stability margin of power systems. In order to coordinate TCSC compensators, the MOPSO multiobjective algorithm with integral of the time-weighted absolute error (ITAE) and figure of demerit (FD) objective functions was used. The MOPSO algorithm optimization results are compared with nondominated sorting genetic algorithm (NSGAII) and multiobjective differential evolution (MODE) algorithms. The optimization results indicated a better performance of the proposed MOPSO algorithm than NSGAII and MODE. The simulations were iterated in two scenarios by creating different loading conditions in generators. The results indicated that the proposed control system, where the coordination between PSS2B power system stabilizers and TCSC compensators using the MOPSO algorithm, is better than power systems in which PSS2B Stabilizers or TCSC compensators are utilized solely. All criteria, e.g., ITAE, FD, maximum deviation range, and the required time for power oscillation damping in hybrid control systems, have been obtained. This means more stability and accurate and proper performance

Design and Stability Analysis of a Super-Twisting Controller for a PS-FBC based Fuel Cell Module

Proton‐exchange membrane fuel cells have been established as a really promising technology, specially due to their high efficiency and scalability features, additionally to their low pollution emissions. In a typical topology, fuel cell module (FCM) is usually integrated into a hybrid power system, where the FCM is designed to satisfy the main power requirements and reduce the current ripple at the fuel cell output. In this framework, the aim of this paper is to analyze and design a sliding mode control (SMC) for a FCM based on an isolated phase‐shifted full bridge converter. This particular topology provides a high conversion ratio and attains a reduction of switching losses, which allow its application in low and medium power systems. From the control viewpoint, the proposed module represents a challenge due to the highly nonlinear behavior and wide operation range of the FCM, together with system parameter uncertainties and perturbations. To solve these issues, a second‐order sliding mode super‐twisting algorithm (STA) is proposed. As its main advantage, the STA reduces significantly the control chattering while preserving several features of conventional SMCs, such as robustness and finite time convergence. In order to analyze the zero dynamics stability, a Lyapunov study is proposed, taking advantage of its particular Liérnad‐type system structure. Finally, the designed algorithm is thoroughly analyzed and validated by computer simulation on a commercial 10‐kW FCM and compared to first‐order SMC.Fil: Anderson Azzano, Jorge Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones en Electrónica, Control y Procesamiento de Señales. Universidad Nacional de La Plata. Instituto de Investigaciones en Electrónica, Control y Procesamiento de Señales; ArgentinaFil: Moré, Jerónimo José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones en Electrónica, Control y Procesamiento de Señales. Universidad Nacional de La Plata. Instituto de Investigaciones en Electrónica, Control y Procesamiento de Señales; ArgentinaFil: Puleston, Pablo Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones en Electrónica, Control y Procesamiento de Señales. Universidad Nacional de La Plata. Instituto de Investigaciones en Electrónica, Control y Procesamiento de Señales; Argentin