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Dielectric barrier discharge (DBD) is widely used in the treatment of skin disease, surface modification of material and other fields of electronics. The purpose of this paper is to design a high-performance power supply with a compact structure for excimer lamps in electronics application.

To design a high-performance power supply with a compact structure remains a challenge for excimer lamps in electronics application, a current-source type power supply in a single stage with power factor correction (PFC) is proposed. It consists of an excitation voltage generation unit and a PFC unit. By planning the modes of the excitation voltage generation unit, a bipolar pulse excitation voltage with a high rising and falling rate is generated. And a high power factor (PF) on the AC side is achieved by the interaction of a non-controlled rectifier and two inductors.

The experimental results show that not only a high-frequency and high-voltage bipolar pulse excitation voltage with a high average rising and falling rate (7.51GV/s) is generated, but also a high PF (0.992) and a low total harmonic distortion (5.54%) is obtained. Besides, the soft-switching of all power switches is realized. Compared with the sinusoidal excitation power supply and the current-source power supply, the proposed power supply in this paper can take advantage of the potential of excimer lamps.

A new high-performance power supply with a compact structure for DBD type excimer lamps is proposed. The proposed power supply can work stably in a wide range of frequencies, and the smooth regulation of the discharge power of the excimer lamp can be achieved by changing the switching frequency. The ideal excitation can be generated, and the soft switching can be realized. These features make this power supply a key player in the outstanding performance of the DBD excimer lamps application.

The main purpose of this paper is to propose a quasi-impedance source (QIS) converter fed switched reluctance motor (SRM) drive. The proposed converter topology is configured for DC link capacitance minimization and power factor (PF) correction.

A QIS converter is used as a front end converter to reduce the bulk capacitance requirement during current commutation and to decline the power ripple. To improve the PF with reduced total harmonic distortion at the input current, the PF current control loop is merged with the QIS converter control loop.

The overall SRM drive speed is regulated over a wide range by controlling the DC link voltage. The voltage regulation can be achieved by pulse width modulation of the QIS converter. Hence, the overall system efficiency has been improved by operating the proposed converter at a low switching frequency. Moreover, the proposed QIS converter uses an advanced repetitive controller to achieve voltage regulation and fewer ripples in torque.

The steady state and dynamic analyzes have been performed on the proposed drive topology. The performance of the proposed topology has been simulated through MATLAB/Simulink environment. A hardware prototype with a processor of Xilinx SPARTAN 6 field-programmable gate array has been used to validate the experimental response with the simulation results.

The purpose of this paper is to present a systematic design procedure along with modeling and simulation of a medium‐scale centralized dc‐bus grid connected hybrid (wind turbine (WT) and photovoltaic (PV)) power system (GCHWPPS) for supplying electric power to a three‐phase medium voltage distribution grid.

The design, modeling, simulation and control of the GCHWPPS are achieved by using Simulink/MATLAB environment.

The case study shows that the proposed system configuration along with the suggested control schemes achieve rapidly, accurately, stably and simultaneously four objectives, i.e. maximum power point tracking of WT and photovoltaic generator, dc voltage regulation/stabilization at the input of the inverter, and high electric power quality injected into the grid from the inverter, fulfilling all necessary practical interconnection requirements while providing additional load power factor correction.

An effective intelligent dynamic control method is used to a proposed GCHWPPS configuration to simultaneously achieve the four mentioned practical objectives while meeting the grid requirements.

The purpose of the paper is to examine the monitoring of electrical energy consumption, measures adopted for reducing energy consumption, barriers to energy efficiency improvement and driving forces for energy efficiency improvement in three industrial clusters. It is intends to capture the managerial perspectives on energy saving practices and to identify the possible energy saving opportunities in small and medium enterprises (SMEs).

Three industrial clusters were identified for the study. Research instrument based in-person survey was conducted in which the authors directly administered the questionnaire to all the 181 organisations. This was thought of to facilitate not so well-educated respondents. The survey took about six months in which 110 units responded. Descriptive statistics, exploratory factor analysis and path analysis were used to draw inferences.

There is ample scope for energy savings in the studied clusters. Energy efficiency in many organisations has deteriorated. Their attitude to embrace new or modern technology is shunning. Management’s belief that prevailing technology is efficient, lack of skilled labour, lack of accessibility to updated or modern technology, and lack of compatibility of new technology are found to be the barriers to energy efficiency improvement. Benchmarking by appropriate governments and publicly financed energy auditing act as the driving forces.

The SMEs must use simple yet powerful energy auditing practices on regular basis to reduce energy consumption. This will not only result in lesser energy costs but also lessen the burden on environment. As these are predominantly small enterprises, appropriate governments interventions are essential to bring the desired change.

The paper aims to explain the investigation of the space vector modulation (SVPWM), in shunt active powers filters (APFs) field, for controlling the generated current.

With the inclusion of the SVPWM control technique, the proposed topology of the two‐level shunt active power filter (APF), based on IGBTs, besides its efficiency in harmonics cancellation and power factor correction, contributes in switching power losses reduction.

The paper provides an extended theoretical study and a detailed explanation of the application of the SVPWM on shunt APFs, and demonstrates how power losses can be reduced by limiting the switching process to the two thirds of the pulse duty cycle.

Simulation and experimental validations will still be requested as to the accuracy of the model and the applicability to the polluted electrical power systems plants.

The paper formulates an easy mathematical method to investigate the SVPWM algorithm with clarification of its various steps. It offers a benefit to people engaged in theoretical and practical research in APFs, inverters, and PWM modulation strategies.

Since, there are few studies which clarify the application of the SVPWM on APFs, the paper may help to understand the mathematical implementation of this control strategy both for controlling the APF current and for gating signals generation.

With the advancement of technology, size, cost, and losses of the switched mode power supply (SMPS) have been decreasing. However, due to the high frequency switching, design of magnetic drives and isolation circuits are becoming a crucial factor in SMPS. This paper presents design criteria, procedure and implementation of AC-DC half bridge (HB) converter with lower cost, smaller size and lower voltage stress on the power switch.

The HB converter is designed in a symmetrical mode with a series coupling capacitor. Isolated power supplies are used for the converter and control circuit. Further, a transformer based isolated gate driver is used to drive both MOSFETs. The control IC works in voltage control mode to regulate voltage by controlling the duty cycle of the MOSFETs.

Control characteristics and performance of the HB converter is simulated using the MATLAB software and prototype of 170 W HB converter is built to validate the analytical results under variable load current and source voltage. The power quality and variation of load voltage at 2 A, 5 A, 7 A are reported.

This paper presents the design of a low-cost HB converter in a symmetrical mode which saves the additional cost of symmetric correction circuit normally required in asymmetrical mode design. This paper also focuses on the selection of primary and secondary side switch, series coupling capacitor, commuting diode, isolated drive and charge equalizer resistor.

This study aims to present a modified interleaved boost converter (MIBC) topology for improving the reliability and efficiency of power electronic systems.

The MIBC topology was implemented with two parallel converters, operated with a −180 degree phase shift. Using this methodology, ripples are reduced. The state-space model was analysed with a two-switch MIBC for different modes of operation. The simulation was carried out and validated using a hardware prototype.

The performance of the proposed MIBC shows better output voltage, current and power than the interleaved boost converter (IBC) for the solar PV array. The output power of the proposed converter is 1.353 times higher than that of existing converters, such as boost converter (BC) and IBC. The output power of the four-phase IBC is 30 kW, whereas that of the proposed two-phase MIBC is 40.59 kW. The efficiency of MIBC was better than that of IBC (87.01%). By incorporating interleaved techniques, the total inductor current is reduced by 29.60% compared with the existing converter.

The proposed MIBC can be used in a grid-connected system with an inverter circuit for DC-to-AC conversion, electric vehicle speed control, power factor correction circuit, high-efficiency converters and battery chargers.

The work presented in this paper is a modified version of IBC. This modified MIBC was modelled using the state-space approach. Furthermore, the state-space model of a two-phase MIBC was implemented using a Simulink model, and the same was validated using a hardware setup.

The purpose of this paper is to address the issue of power quality through a case study in an IT‐intensive modern office building.

This paper presents results from a power quality audit conducted last year. Firstly, the power site inspection included: (a) a walk‐down of the facility's electrical system to inspect the condition of equipment and becoming familiar with the electrical system; (b) interviewing facility electrical personnel and end‐users on failure of equipment; (c) identifying and collecting the electronic equipment that is most sensitive to power disturbances; (d) requesting and reviewing equipment literature and electromagnetic compatibility characteristics; (e) after that, in the power quality monitoring, voltage and current were measured at various floors.

It was found that the main problems for the equipment installed were harmonics and leakage currents. The paper examines the causes and effects of power disturbances that affect computer or any other microprocessor based equipment and analyses the disadvantages of modern power supplies.

This provides useful information for facilities managers on the current state of power disturbances. The convenience of “enhanced power supply” is also discussed. Finally, it is addressed the role of standards on the protection of IT and the implications for the final costumer.

This paper has provided empirical data from a power site survey developed in a high tech building. This case study demonstrates the impacts of generalized electronic devices on the power quality of the buildings and the implications on energy uses.

THE total scope of aerodynamic problems in helicopter design is extremely wide. One can find here such topics as laminar aerofoil sections, boundary layer control, compressibility effects (with all the unpleasant implications of the transonic region), aero‐elastic instability, and, of course, all of the mathematically challenging problems of stability in hovering and in forward flight.