Input Ac Mains Research Articles

A Universal Input PFC CSC Converter in Low Power Consumer Lighting Applications

ABSTRACT A power factor corrected (PFC) Canonical Switching Cell (CSC) converter is proposed for low power consumer light-emitting diode (LED) lighting applications. The proposed CSC converter is intended to operate in discontinuous inductor current mode (DICM) to realize improved power quality performance. In low power consumer lighting applications, the CSC converter is more suitable due to its many benefits such as high energy storing capability, high input and low output impedance as compared to other buck-boost converters. This paper describes the different performance parameters of the proposed converter. Application of lighting load is also examined in view of achieving improved power quality over the wide input AC mains voltage. The measured converter efficiency of a laboratory prototype is found to be 93.8% and total harmonic distortion (THD) of the input current is observed only 6.52% at 230 V AC mains for a prototype of 50 W. Due to less switching losses, the proposed converted has shown much-improved results as compared to the conventional buck-boost converter.

Improved power quality based high brightness LED lamp driver

This paper deals with a power factor corrected (PFC) improved power quality based LED lamp driver. The proposed driver consists of a PFC Cuk DC-DC converter which operates in continuous conduction mode (CCM) to improve the power quality at input AC mains. The design, modeling and simulation of an 18W LED (six 3W LEDs in series) driver are carried out in MATLAB/SIMULINK environment for a 220V, 50 Hz AC mains with constant load voltage of 72V. Each LED has a forward voltage of 12V and a forward current of 0.25A. The power quality indices such as total harmonic distortion of AC mains current (THDi), power factor (PF), distortion factor (DF), displacement power factor (DPF) and crest factor (CF) are calculated to study the behavior of proposed LED lamp driver.Keywords: Continuous Conduction Mode (CCM), Cuk DC-DC Converter, Diode Bridge Rectifier (DBR), LED Lamp Driver, Power factor Correction (PFC)

Comparison of power quality indices and apparent power (kVA) ratings in different autotransformer-based 30-pulse AC–DC converters

Three-phase multipulse AC–DC converters (MPC) are developed for improving power quality to reduce harmonics in ac mains and ripples in dc output. This study, based on technical and economic factors, compares different autotransformer-based 30-pulse AC–DC converters. In thispaper, the comparison of two topologies of autotransformer-based 30-pulse AC–DC converter has been presented. In topology A, three-phase AC voltages are given to the autotransformer, which produces five sets of three-phase voltage and, in topology B, three-phase AC voltages are given to the autotransformer, which produces three sets of five-phase voltages of same magnitude and distributed in time through phase shifts of 12◦ . Topology A included polygon, hexagon, star, fork, and T-connected autotransformer-based 30-pulse AC–DC converters, and topology B Included polygon, and T-connected autotransformer-based 30-pulse AC–DC converters. These converters have been implemented and simulation using Matlab/Simulink software for similar ratings under different load conditions has been performed. A set of power-quality indices on input ac mains and on a dc bus for a DTCIMD fed from different 30-pulse AC–DC converters is given to compare their performance. Economic comparison of 30 pulse AC–DC converters is based on the apparent power (kVA) ratings of the different autotransformer for 30 pulse AC–DC converters.

Delta/Fork-Connected Transformer-Based 72-Pulse AC–DC Converter for Power Quality Improvement

ABSTRACTThis paper presents a delta/fork-connected transformer-based 72-pulse AC–DC converter feeding direct torque-controlled induction motor drives (DTCIMDs) for improving power quality. The proposed converter consists of two paralleled 18-pulse AC–DC converters along with pulse-doubling circuit at DC bus. The pulse-doubling circuit is used in achieving the pulse multiplication in a 36-pulse AC–DC converter. The Thirty-six pulse topology is obtained via two paralleled 18-pulse AC–DC converters each of them consisting of a 9-phase (9-leg) diode-bridge rectifier. The design of proposed magnetics shows the flexibility in varying the voltage ratio of the delta/fork-connected transformer for making it suitable for retrofit applications where a 6-pulse diode-bridge rectifier is being utilized. Independent operation of paralleled diode-bridge rectifiers, i.e. DC-ripple re-injection methodology, requires a Zero Sequence Blocking Transformer (ZSBT). Finally, a tapped interphase reactor is connected at the output of ZSBT to double the pulse numbers of output voltage up to 72 pulses. The proposed 72-pulse AC–DC converter with the DTCIMD has been implemented and simulated using Matlab/Simulink software. Simulation results confirmed the significant improvement of the power quality indices on input AC mains and on DC bus (consistent with the IEEE-519 standard requirements) at the point of common coupling. Also, a laboratory prototype is implemented using the proposed design and the experimental results confirm the simulation results at various loads. Results show that input current total harmonic distortion (THD) is less than 3% for the proposed 72-pulse topology at variable loads. Furthermore, near unity power factor is obtained for a wide operating range of the drive.

Zigbee Based Energy Efficient LED Lighting System

In recent years high brightness LED lamps are opening up new opportunities of cost and energy saving towards variety of lighting applications. However they also require LED driver and control circuit compare to gas filled lamps when operating at input AC mains. Thus an efficient driving circuit is essential for its optimal performance. In this paper a remote monitoring and controlling system based wireless sensor network is implemented for LED lighting according to the user’s state, which basically controls illumination intensity of a lighting device according to object movement and brightness of surrounding. Then this system can extend communication capability to the existing street lighting system through the ZigBee and this idea will be very useful for subway, industries and household application to effectively reduce the power consumption.

Design and development of a LED Driver prototype with a Single-Stage PFC and low current harmonic distortion

This paper presents a LED driver design and development with a single-stage power factor correction (PFC) for low power home LED lamps. A buck-boost converter was simulated in CCM (Continuous Conduction Mode), DCM (Discontinuous Conduction Mode) und BCM (Boundary Conduction Mode) with a current control scheme to improve power quality. After a comparison of simulated performance of three conduction modes, the buck-boost converter in boundary conduction mode (BCM) had the best performance and was implemented. The prototype has an on-time current control and EMI filter, aiming to the improvement of energy quality ratings and pursuing the IEC 61000-3-2 standards for type C equipment for a 120 V, 60 Hz input AC mains. Besides, the prototype was compared with some LED Bulbs present in the Colombian market in indices as PF and total harmonic distortion (THD). Finally, the conclusions are presented.

Improved Power Quality Switched-Mode Power Supply Using Buck–Boost Converter

The analysis, design, modeling and development of a switched mode power supply (SMPS) for computers is presented here for improved power quality. The proposed SMPS is capable to mitigate existing problems in a conventional SMPS. It is designed to attain close to unity input power factor (PF) and low harmonic distortion at the input ac mains with regulated multiple dc output voltages. A non-isolated front end power factor corrected converter is designed in discontinuous conduction mode (DCM) of operation and control. Simulated performance of proposed power supply is presented to validate the design and to demonstrate the performance with near unity PF operation. Experimental validation of the proposed SMPS is also carried on a prototype built in the laboratory and the test results are compared with the simulation results to validate the design and modeling. An improved power quality is achieved with almost unity power factor in wide range of input ac voltages and loads.

Single-stage unity power factor based electronic ballast

This paper deals with the design, modeling, analysis and implementation of unity power factor (UPF) based electronic ballast for a fluorescent lamp (FL). The proposed electronic ballast uses a boost AC–DC converter as a power factor corrector (PFC) to improve the power quality at the input ac mains. In this single-stage UPF based electronic ballast, boost PFC converter and a half bridge series resonant inverter (HBSRI) share a common power switch. Thus one power switch is reduced as compared to the conventional two-stage approach. The design, modeling, analysis and implementation of this topology were carried out in MATLAB-Simulink environment for a T8 36 W, 220 V, 50 Hz fluorescent lamp. The switching frequency was kept more than the resonant frequency of the inverter, to ensure the zero voltage switching (ZVS) operation of both power switches. This resulted in reduction of high frequency switching losses. The power quality parameters such as displacement power factor (DPF), distortion factor (DF), power factor (PF), crest factor (CF) and total harmonic distortion of ac mains current (THDi) were evaluated to analyze the performance of proposed electronic ballast. Test results on a developed prototype of PFC electronic ballast were included to validate the design and simulated results.

Performance Analysis of various Power Converters for Power Factor Correction in BLDC Motor with Fuzzy Logic Controller

Enhance the efficiency of the motor drive by Power Factor Correction (PFC) play a critical part in the energy saving during energy consumption. Permanent magnet brushless DC Motor (PMBLDCM) drives are being utilized in numerous variable speed applications because of their high productivity, quiet operation, high reliability, simplicity of control, and low maintenance requirement. These drives have power quality issues and poor power factor at input AC mains as they are mostly fed through diode bridge rectifier. To overcome such issues a single stage single-switch power factor correction AC-DC converter topology are utilized. This paper gives the relative evaluation of the different converter with Proportional Integral Controller (PIC) And Fuzzy Logic Controller (FLC). In this system, the speed of the motor is shifted by the Impedance Source Inverter (ZSI) dc voltage. The proposed drive is realized to achieve a unity power factor at ac mains for a broad scope of speed control and supply voltage flucation. A MATLAB/Simulink environment is used to reproduce the model to fulfill an extensive variety of speed control with improved Power Quality (PQ) at the supply.

Buck converter‐based power supply design for low power light emitting diode lamp lighting

This study deals with the analysis and implementation of an HPF (high power factor) single-stage, single switch buck converter-based power supply design for an LED (light emitting diode) lamp load of 13 W operated at the universal ac mains. In general purpose lighting applications, a buck converter is a good candidate for power factor correction with low component count and reduced cost. In low-power lighting, it is a tough task to control the THD i (total harmonic distortion) of ac mains current under the limits of strict international standards such as IEC-61000-3-2 with universal ac mains for class D equipments. In the proposed optocouplerless topology, HPF operation at input ac mains is achieved by operating the buck ac-dc converter in continuous conduction mode. The design, modelling and simulation of the proposed topology are executed using MATLAB-Simulink and sim-power system toolboxes. A prototype of the power supply for LED lamp is developed for multiple LEDs connected in series configuration. The efficiency of the proposed LED lamp driver is observed as 83.76% at rated voltage of 220 V and the THD of ac mains current less than 17.27% for a wide range of voltages of 90-270 V.

Three-phase modular single stage full-bridge converter for switched mode power supplies

In this paper, the modular development of a three-phase single stage ac-dc power converter based on single-phase ac-dc isolated full-bridge converter for telecom power supply applications is presented. Three single-phase converter modules are series connected to form a three-phase converter system to achieve balanced three-phase currents. This paper analyses the operation of a modular converter in continuous conduction mode (CCM) of power factor correction. The performance of such a modular full-bridge converter system has been evaluated with simulation based on a MATLAB model and the results are also presented. The main objective of the proposed system is to reduce the number of stages and improve the power factor of the input ac mains current. The proposed scheme offers simple control strategy, electrically isolated output, single-stage power conversion, elimination of power transformer at the front end and inherent power factor correction (PFC) for medium rating power supplies.

Single-Phase PFC Converter for Plug-in Hybrid Electric Vehicle Battery Chargers

In this paper, a front end ac–dc power factor correction topology is proposed for plug-in hybrid electric vehicle (PHEV) battery charging. The topology can achieve improved power quality, in terms of power factor correction, reduced total harmonic distortion at input ac mains, and precisely regulated dc output. Within this context, this paper introduces a boost converter topology for implementing digital power factor correction based on low cost digital signal controller that operates the converter in continuous conduction mode, thereby significantly reducing input current harmonics. The theoretical analysis of the proposed converter is then developed, while an experimental digital control system is used to implement the new control strategy. A detailed converter operation, analysis and control strategy are presented along with simulation and experimental results for universal ac input voltage (100–240V) to 380V dc output at up to 3.0 kW load and a power factor greater than 0.98. Experimental results show the advantages and flexibilities of the new control method for plug-in hybrid electric vehicle (PHEV) battery charging application. DOI: http://dx.doi.org/10.11591/ijpeds.v2i3.1255

MITIGATION OF HARMONICS USING THYRISTOR BASED 12 PULSE VOLTAGE SOURCE PWM RECTIFIER

Three-phase thyristor rectifiers have been used in industries for obtaining a variable dc voltage, but they have a problem of including large lower-order harmonics in the input currents. For high-power applications, a 12-pulse configuration is useful for reducing the harmonics, but it still includes the (12m ± 1) th (m: integer) harmonics. In order to further reduce the harmonics, this paper proposes to supply a ramp wave voltage at the input of a 12-pulse phase-controlled rectifier. Theoretical investigation to reduce harmonics is presented, and a strategy to control the regulated voltage and unity power factor at input side based on 12 pulse modulation technique. This paper discuss the impact of using 3-phase and 12-pulse rectifier circuit commonly found in unity power factor at input ac mains and regulate output voltage. The 12-pulse topology is known to be more expensive, but produce the least input current harmonics. However, the latter statement is completely true under balanced line conditions. In practice, the lines are inherently unbalanced. Hence, the question of whether the 12-pulse rectifier will indeed perform better in terms of the harmonics injected to the line is still under on-going discussions. This presents the modelling and simulation of both rectifier topologies to compare their input current and regulated output voltage harmonics. The rectifiers are modelled using the MATLAB/SIMULINK simulation model and several common cases conditions will be simulated to compare their harmonic levels.

Power Factor Correction Boost Converter Based on the Three-State Switching Cell

The need for solid-state ac-dc converters to improve power quality in terms of power factor correction, reduced total harmonic distortion at input ac mains, and precisely regulated dc output has motivated the investigation of several topologies based on classical converters such as buck, boost, and buck-boost converters. Boost converters operating in continuous-conduction mode have become particularly popular because reduced electromagnetic interference levels result from their utilization. Within this context, this paper introduces a bridgeless boost converter based on a three-state switching cell (3SSC), whose distinct advantages are reduced conduction losses with the use of magnetic elements with minimized size, weight, and volume. The approach also employs the principle of interleaved converters, as it can be extended to a generic number of legs per winding of the autotransformers and high power levels. A literature review of boost converters based on the 3SSC is initially presented so that key aspects are identified. The theoretical analysis of the proposed converter is then developed, while a comparison with a conventional boost converter is also performed. An experimental prototype rated at 1 kW is implemented to validate the proposal, as relevant issues regarding the novel converter are discussed.

Particle swarm optimisation for power quality improvement of a 12-pulse rectifier-chopper fed LCI-synchronous motor drive

This paper investigates the optimised passive filter combination for power quality improvement of a 12-pulse rectifier-chopper fed load commutated inverter LCI based synchronous motor SM drive. The search of optimised component values of passive filter combination is carried out by a modified particle swarm optimisation PSO algorithm with an objective of reduction in total harmonic distortion THD and improvement in power factor PF of AC mains current. The proposed PSO algorithm is formulated and implemented in the MATLAB-SIMULINK environment for three varieties of loads on LCI-SM drive, namely constant torque variable speed loads, constant speed variable torque load and variable speed variable torque load to meet the requirements in wide range of applications. The obtained results show considerable improvement in the power quality at the input AC mains of the LCI-SM drives for all varieties of loads and presents a basis for selection of a suitable passive filter combination.

Harmonic mitigator based on 12-pulse ac–dc converter for switched mode power supply

A novel harmonic mitigator based on the 12-pulse ac–dc converter, which is capable of suppressing up to 11th harmonics, is presented with reduced magnetic rating and low total harmonic distortion (THD) of ac mains current. A set of power quality indices on input ac mains and magnetic ratings for various autoconnected transformer configurations for the 12-pulse converter feeding a low voltage, high current and 12 kW switched mode power supply is also presented so that the best autoconnected transformer configuration can be chosen according to the requirements for this application. A laboratory prototype of the proposed ac–dc converter is developed and the test results are presented to validate the design and model of the converter system.

Power Quality Improvement in Switched Mode Power Supplies Using Autoconnected Transformer Based 9-Phase ac-dc Converters

Switched Mode Power Supplies (SMPS) of medium power ratings are extensively used in heating, welding and telecommunication power supply applications. Invariably, they use a 3-phase ac-dc converter at the front end. In this paper, different autoconnected transformer-based 9-phase ac-dc converter configurations are designed, modeled and simulated to feed such medium capacity SMPS for improving the power quality indices at the point of common coupling (PCC). The autoconnected transformer is designed suitable for producing 9-phase voltages of same magnitude and having equal phase shift. The proposed 9-phase ac-dc converters are found capable of suppressing up to 17th harmonic in the supply current along with the power factor improvement close to unity at varying loads. A set of power quality indices on input ac mains and magnetic ratings for various autoconnected transformer configurations for this SMPS are also presented so that the best converter configuration can be chosen according to the requirements for a particular application.

Direct Single-stage Power Converter with Power Factor Improvement for Switched Mode Power Supply

This paper presents a direct single-stage power converter using single-phase isolated full-bridge converter modules, with inherent power factor correction (PFC) for a 12 kW switched mode power supply (SMPS). The advantages of the proposed converter are its simple control strategy, reduction in number of conversion stage, low input line current harmonics, and improvement in power factor. Analysis of the single-stage converter is carried out in continuous conduction mode of operation. Steady-state analysis of the proposed converter is conducted to obtain converter parameters. A systematic design procedure is also presented for a 12k W converter with a design example. The effect of load variation on SMPS is also studied in order to demonstrate the effectiveness of the proposed converter for the complete range of load conditions. A set of power quality indices on input ac mains for an SMPS fed from a single-stage converter is also presented for easy comparison of their performance.

Autoconnected transformer-based 18-pulse ac–dc converter for power quality improvement in switched mode power supplies

Switched mode power supplies (SMPS) are commonly used in telecommunication towers and welding equipments. In medium capacity SMPS, power quality at the utility interface is a major concern. A new autoconnected transformer is presented for power quality improvement in 18-pulse ac–dc converter fed SMPS with least magnetic rating. Various autoconnected transformers are studied for 18-pulse ac–dc rectification and a new autoconnected transformer is selected to improve the power quality of the supply current. The effect of load variation on SMPS is studied to demonstrate the performance and effectiveness of the proposed 18-pulse ac–dc converter-based SMPS in the wide operating range of the power supply system. A set of power quality indices at input ac mains and magnetic rating of various autoconnected transformers are presented to compare their performance. Laboratory prototype of the proposed autoconnected transformer-based 18-pulse ac–dc converter is developed and test results are presented to validate the proposed design and developed model of the converter system.

Power quality improvement in load commutated inverter-fed synchronous motor drives

The load commutated inverter (LCI)-fed synchronous motor (SM) drive, also known as commutatorless motor (CLM) drive, is popular in high power applications. Most promising features of these drives include high efficiency, economic operation, flexibility of operation and variable speed in high power range, which led to their applications in blowers, fans, pumps, mill drives for a range of industries as mining, water treatment plants, chemical, paper, textile, cement, rolling mills and petrochemical plants. However, the power quality (PQ) concerns have resulted in a set-back for such applications of these drives. This study investigates various topologies for the mitigation of PQ problems in LCI-fed SM drives using multi-pulse AC-DC converters. A set of hybrid topologies is proposed to feed CLM, which use a multi-winding transformer and diode rectifiers with a chopper cascaded named as -rectifier-chopper-. These topologies improve PQ at AC mains, that is, reduce total harmonic distortion in the input current and correct the power factor. It also presents a basis for selection of a suitable AC-DC converter for PQ improvement at the input AC mains of the LCI-fed SM drives.