Power Factor Correction Operation Research Articles

A Multimode Power Processor With Wired and Wireless Battery Charging for Electric Vehicle

The propulsion unit is the prime power module in an Electric Vehicle (EV) that keeps it moving. This module includes a propulsion motor and a power electronic interface that converts DC to three phase AC for driving the motor. In addition to this, separate power electronic modules are used for on-board wired charging and wireless charging. This paper proposes a multimode power processor for EV capable of serving the purpose of three different power modules required for propulsion, wired charging and wireless charging. This optimizes the weight, volume, and cost of the EV as separate power modules are avoided for three different modes. This paper also proposes a new scheme for the transmitting side power electronic module that taps power from the single-phase utility grid and generates high frequency AC using a resonant inverter for wireless power transfer. In both the wired and wireless charging method, the proposed technique draws power from the single-phase wall outlet, charges the EV battery pack with constant current-constant voltage (CC-CV) charging logic and performs power factor correction operation at the input AC grid side. A laboratory scale prototype is developed for experimentally validating the proposed concept with a 24 V, 30 Ah battery set and a 24 V, 400 W BLDC motor.

Power quality improvement in BLDC motor drive using PFC converter

The use of brushless DC motors (BLDC) in low-power appliances is increasing because of their features of high efficiency, wide speed range, and low maintenance. This project deals with a power factor correction (PFC) based BL Landsman converter-fed brushless DC motor drive as a cost-effective solution for low-power applications. The speed of the BLDC motor is controlled by varying the DC-link voltage of the voltage supply electrical converter feeding the BLDC motor drive. A low-frequency switch of the VSI is used for achieving the electronic commutation of the BLDC motor for reduced switch losses. The PFC-based letter of the alphabet device is designed to control in discontinuous inductance current mode; therefore utilizing a voltage follower approach which needs one voltage sensing element for dc-link voltage management and PFC operation. The projected drive is meant to control a large variety of speed management with improved power quality at AC mains. The performance of the projected drive is valid with experimental results obtained on a developed epitome of a PFC device. This manuscript deals with the configuration of a power factor correction converter feeding a drive of brushless DC motors for medium and low-power equipment. The DC link voltage of the drive system is maintained by a single DC voltage actuator. Two control converters for the BLDC motor drive have been implemented. The control strategy is based on a PFC-Landsman converter-fed BLDC motor drive. Comparison has been made in PI controller-based converter in terms of minimizing ripple and improving the power factor of BLDC Motor drive. The proposed work has been implemented under MATLAB/Simulink environment

Performance investigation of bridge-less power factor correction circuit with MOSFET

The aim of this paper is to study and investigate the performance of power factor correction (PFC) circuit implemented with the semi bridge-less configuration. The transistor-diode module APT50N60JCCU2 has been used in the proposed circuit and the UCC28070 controller has been used as a controlling device for the power factor correction (PFC) circuit. Testing has been performed in two steps. In the first step, the test was conducted<br /> on (230 Vac), while in the second step, the test was conducted on (115 Vac) as alternating input voltages. The testing results of both voltages were compared and analyzed in terms of efficiency, power factor, total harmonic distortion (THD) in order to determine the efficiency of the power factor correction circuit. The results obtained indicate that this circuit has efficiency up to 97% and a power factor close to 0.91 with the input voltage of 230 V.

A Standard Two Stage On-Board Charger With Single Controlled PWM and Minimum Switch Count

A novel two-stage standard battery charger having minimum switch count using a single controlled PWM signal is presented in this paper for Electric Vehicle (EV) charging application. The first stage is responsible for AC to DC conversion with power factor correction (PFC) operation that consists of two switches and two diodes. The second stage is a DC-DC converter having a half bridge LLC resonant configuration along with an isolation transformer. The complete charger consists of only four switches and four diodes, which is minimum among the reported literatures. Moreover, unlike a conventional control strategy that requires multiple separate controlled PWM signals for different switches, the new control scheme manages both the PFC operation as well as constant current–constant voltage (CC-CV) optimal battery charging with a single controlled PWM signal. The detailed operation and its modeling are presented in this paper. A 470 W scaled down laboratory prototype is built to validate the proof of concept. The proposed charger is tested to charge a battery set of 24 V, 30 Ah using CC-CV logic with a maximum efficiency of 97.6%. The prototype is also tested with resistive load at its rated power and dynamics results are captured. A TMS320F28335 DSP board from Texas Instrument is used for implementing the control technique.

Totem-Pole PFC Reliability and Performance Improvement With Advanced Controls

Totem-pole power factor correction (PFC) is a simple and highly efficient topology. It is being widely used in high-density and high-efficiency power supply design. However, engineers still face many design challenges, including PFC current reversing prevention at input voltage drop, lightning surge protection, current harmonic reduction, and ac crossover current spike elimination. These challenges are not closely related to each other and there is no single control that can solve all the design issues. This article reviews the main design challenges and provides comprehensive solutions to these issues. Most of the solutions are novel or are used for the first time in PFC control. These solutions are integrated into the industry’s first continuous conduction mode (CCM) totem-pole PFC analog controller IVCC1102 <xref ref-type="bibr" rid="ref1" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">[1]</xref> . A 2.5 kW SiC-based totem-pole PFC prototype <xref ref-type="bibr" rid="ref1" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">[1]</xref> is built to demonstrate the robustness and performance improvement with the proposed solutions.

A Cascaded Controller for a Grid-Tied Photovoltaic System With Three-Phase Half-Bridge Interleaved Buck Shunt Active Power Filter: Hybrid Control Strategy and Fuzzy Logic Approach

This paper focuses on the control development of a grid-tied photovoltaic system coupled with a shunt active power filter. The considered power system includes a PV panel, a single-capacitor three half-bridge interleaved buck converter connected to a three-phase power grid and a nonlinear load. This study aims to accomplish simultaneously three objectives: i) to ensure a high compensation level of current harmonics and reactive power consumed by the nonlinear load in order to perform power factor correction at the grid side; ii) to extract the maximum power from the PV panel regardless the climatic conditions; iii) to regulate the dc bus capacitor voltage to its reference provided by the MPPT controller. To this end, a controller using a two-loop cascade strategy is designed. First, the inner loop is developed with the hybrid automaton approach to formulate the switching control signals with the aim of guaranteeing a unitary power factor. Second, the outer loop is designed using fuzzy logic control to ensure the regulation of the photovoltaic voltage, while the perturb and observe algorithm is employed to perform maximum power point tracking. Finally, the system with the developed control scheme is simulated using MATLAB/SimPowerSystems environment. The obtained results confirm that the proposed controller is able to achieve the previous objectives under varying environmental conditions.

An efficient soft-switched vienna rectifier topology for EV battery chargers

The requirement of high power rated, efficient and high power density grid connected converters has increased due to their extended use in multiple applications such as battery chargers. The proliferation of electric vehicles (EVs) in the transportation market is essentially associated with the performance and reliability of battery chargers. An efficient, compact and fast battery charger is indispensable in order to provide a way to charge an EV in a short time. In view of this fact, this article proposes a soft-switching three-level T-type vienna rectifier, which can be used as a front-end power stage converter in an on-board EV battery charger. The proposed topology achieves high efficiency and high power density by employing soft-switching strategy, which is achieved by incorporating a simple auxiliary network in the proposed circuit. The reduced component stresses and simple control strategy make it an appealing candidate for EV industries to develop this front-end PFC rectifier as a fast battery charger. The high switching operation with reduced power losses, regulated DC at the output, low-harmonic grid current and power factor correction operation are achieved with the proposed topology. The construction, operating principle and simulation analysis of the proposed converter are discussed in detail. In order to show the stand-point of the proposed scheme, a fair comparison of the proposed soft-switched converter with an existing soft-switched 3-level neutral-point diode-clamped converter is carried out in terms of the number of components and complexity in the PWM signals generation. Additionally, an efficiency comparison of the suggested converter is carried out with some existing well-known rectifier topologies at different power loads. The practical implementation of the proposed power converter scheme is checked by building a laboratory-prototype to perform an experimental analysis.

A 1-MHz Resonant LED Driver With Charge-Pump-Based Power Factor Correction

This article presents the design and implementation of a resonant LED driver. The driver structure comprises a charge-pump-based power factor correction (PFC) converter and a class-DE dc–dc converter. The PFC converter uses a charge-pump circuit that achieves PFC inherently. The class-DE converter comprises a series-resonant tank and a high-frequency transformer. Both the converters share the same half-bridge and gate-driving circuit, resulting in an integrated-stage architecture. The inherent PFC operation limits the controller responsibility to the regulation of the output current. The overall converter operates with zero-voltage switching (ZVS) across the entire load range, allowing for increased switching frequencies with reduced switching losses. A 1-MHz prototype using wide bandgap (WBG) switching devices is built and tested. The prototype delivers up to 42 W of output power, with a power density of 1.8 W/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> . A power factor of 0.99 and a total harmonic distortion (THD) of 6% are achieved, with an efficiency of 90% at full load. The input current harmonic magnitudes are well within the IEC 61000-3-2 standard limits for class-C devices. Burst-mode (ON/OFF) modulation is used for output current regulation between 20 and 900 mA for dimming functionality.

A novel tri‐capacity battery charger topology for low‐voltage DC residential nanogrid

This study communicates a single-stage, 3-ɸ, rooftop solar photo voltaic (PV) and grid compatible tri-capacity battery charger (TBC) topology for a home-based low voltage direct current nanogrid (LVDC NG). The proposed architecture performs power factor correction drawing sinusoidal grid currents at unity power factor, single-stage rectification of 3-ɸ grid voltages and constant current mode battery charging simultaneously. The employed control scheme is experimentally validated on a 120 W scaled-down hardware prototype energising three lead-acid-based battery energy storage system (BESS) of nominal voltages 48/36/24 V and capacities 28/21/14 Ah, respectively. The obtained results affirm the effective operation of the LVDC NG under islanded/grid-to-battery and battery-to-grid modes. Further, an extension to the proposed work where the TBC functions charging a single BESS is put forward and validated adding merit to the proposed work.

A Sliding Surface for Controlling a Semi-Bridgeless Boost Converter with Power Factor Correction and Adaptive Hysteresis Band

This paper proposes a new sliding surface for controlling a Semi-Bridgeless Boost Converter (SBBC) which simultaneously performs Power Factor Correction (PFC) and DC bus regulation. The proposed sliding surface is composed of three terms: First, a normalized DC voltage error term controls the DC bus and rejects DC voltage disturbances. In this case, the normalization was performed for increasing system robustness during start-up and large disturbances. Second, an AC current error term implements a PFC scheme and guarantees fast current stabilization during disturbances. Third, an integral of the AC current error term increases stability of the overall system. In addition, an Adaptive Hysteresis Band (AHB) is implemented for keeping the switching frequency constant and reducing the distortion in zero crossings. Previous papers usually include the first and/or the second terms of the proposed sliding surface, and none consider the AHB. To be best of the author’s knowledge, the proposed Sliding Mode Control (SMC) is the first control strategy for SBBCs that does not require a cascade PI or a hybrid PI-Sliding Mode Control (PI-SMC) for simultaneously controlling AC voltage and DC current, which gives the best dynamic behavior removing DC overvoltages and responding fast to DC voltage changes or DC load current perturbations. Several simulations were carried out to compare the performance of the proposed surface with a cascade PI control, a hybrid PI-SMC and the proposed SMC. Furthermore, a stability analysis of the proposed surface in start-up and under large perturbations was performed. Experimental results for PI-SMC and SMC implemented in a SBBC prototype are also presented.

Current Interactions Mitigation in 3-Phase PFC Modular Rectifier through Differential-Mode Choke Filter Boost Converter

In this paper, a new way to mitigate the current interactions is proposed. The problem of current interactions arises when a modular three-phase (3-phase) rectifier (three single-phase modules) with boost converter for power factor correction (PFC) is used. A new differential-mode choke filter is implemented in the developed boost converter. The choke here is a specially made differential inductor in the input of the boost converter that eliminates the known current interactions. To prove the new concept, a study of the level of mitigation of the current interactions is presented. The control is operated in continuous driving mode (CCM), and the popular UC3854B circuit was used for this. The rectifier proposal is validated through a set of simulations performed on the PSIM 12.0 platform, as well as the construction of a prototype. With the results obtained, it is confirmed that the differential-mode choke filter eliminates the current interactions. It is observed that at the input of the rectifier, a sinusoidal alternating current with a low level of harmonic distortion is consumed from the grid. The sinusoidal shape of the phase current proves that a better power factor capable of meeting the international standards is obtained, and that the circuit in its initial version is operational. This proven result promises a good PFC operation, to guarantee the better quality of the electrical energy, being able to be applied in systems that require a high PFC, e.g., in battery charging, wind systems, or in aeronautics and spacecrafts.

A Class-E-Based Resonant AC-DC Converter With Inherent PFC Capability

This paper investigates the use of the class-E inverter for power factor correction (PFC) applications. Analytical and state-space models are derived showing the class-E inverter's capability of achieving inherent PFC operation with a constant duty cycle. The inherent PFC operation limits the controller responsibility to the regulation of the output voltage, which is key for resonant converters with challenging control. A converter incorporating a diode bridge, a class-E inverter, and a class-D rectifier is presented for the PFC stage in single-phase offline converters. A prototype is designed to validate the analysis and presented design method. The prototype operates with zero-voltage switching (ZVS) across the load range and achieves up to 211 W of output power at an efficiency of 88%, with an inherent power factor of 0.99 and a total harmonic distortion (THD) of 8.8 %. Frequency modulation is used to achieve lower output power down to 25 W, with a power factor of 0.95, THD of 28 %, and an efficiency of 88 %.

Performing reactive power compensation of three-phase induction motor by using parallel active power filter

Nowadays, the problem of power quality increases day by day. Harmonic current and reactive power are the important factors disturbing the power quality. The induction motors draw both harmonic current and reactive power from the grid. Reactive power and harmonic current lead to heat losses and decrease in the efficiency of the transmission lines. Passive and active filter applications have been used to solve these problems. There are some disadvantages of passive filters. Large physical dimensions and resonance with load can be shown as examples for these disadvantages. Therefore, the application areas of Active Power Filter (APF) are rapidly developing due to the fact that they can be applied together with harmonic and reactive power compensation as appropriate control methods. This paper proposes a MATLAB/Simulink simulation to perform power factor correction and reactive power compensation of three-phase induction motor by using three-phase Parallel Active Power Filter (PAPF). In order to generate PAPF’s reference currents the Sine Multiplication Technique (SMT) is used. Simulation studies are presented to be able to assess the performances under different motor operating conditions. The proposed hysteresis controller based PAPF filter makes the power factor up to 1 and the reactive power compensation of the three-phase induction motor.

Design and Implementation of Four-Switch Current Sensorless Control for Three-Phase PFC Converter

Four-switch current sensorless control for three-phase four-switch converter with power factor correction (PFC) function is presented in this letter. In comparison with conventional multiloop control methods, the proposed control strategy requires sensing of two line voltages and two capacitor voltages only to achieve PFC function. As there is no sensing current, the proposed sensorless control scheme reduces the cost and complexity of design. The performance of the proposed control is validated by its implementation in digital signal processing (DSP) TMS320F28335, and the result shows that the proposed scheme is able to provide comparable PFC performance without sensing current.

A Multiplexing Ripple Cancellation LED Driver With True Single-Stage Power Conversion and Flicker-Free Operation

Although a single-stage off-line power light-emitting diode (LED) driver can achieve low cost and high efficiency, the notorious double-line-frequency flicker issue with a single-stage LED driver limits its usage in high-quality lighting applications. To solve lighting flicker, as well as maintain a low cost and high efficiency, a multiplexing ripple cancellation (MRC) LED driver is proposed in this paper. One switching cycle is divided into two intervals. During the first interval, the proposed LED driver operates as a conventional LED driver that transfers energy from the ac input to LED output, performs power factor correction, and generates the main output voltage. The main output voltage has a double-line-frequency ripple like in a conventional design. During the second interval, the proposed LED driver transfers energy from the ac input again to generate an opposite ripple voltage to cancel the ripple voltage from the main output. In this way, the voltage across the LED load is a dc to achieve flicker-free LED driving performance. More than 99% of the output power goes through one-time power conversion, while less than 1% goes through two-time power conversion. A 7.5-W experimental prototype is built and tested to verify the design concept.

An Interleaved Three-Phase PWM Single-Stage Resonant Rectifier With High-Frequency Isolation

This article proposes a novel interleaved three-phase pulsewidth modulation (PWM) single-stage resonant ac–dc converter with high-frequency isolation. The proposed converter comes from an interleaved three-phase power factor correction (PFC) semistage and a three-phase LLC resonant dc–dc semistage. Soft-switching commutation can be achieved on the power switches in this converter including zero-voltage-switching- on on the primary side power switches and zero-current-switching- off on the secondary diodes. The LLC resonant tank in the dc–dc semistage serves as a bandpass filter that attenuates the line-frequency ripple and keeps the switching frequency component passing through the transformer. The high frequency transformer keeps in a small size. Steady-state analysis of the resonant dc–dc semistage for PWM control is proposed to analyze the dc-link voltage stress. Moreover, the dc-link capacitor value can be greatly reduced without affecting the PFC operation. A prototype that converts a wide three-phase input voltage to 300 V dc output voltage is built and tested. The experimental results present an almost unity power factor with a conversion efficiency as high as 96.3% with total harmonic distortion as low as 3.86% at a full-load condition.

Integrated converter for plug‐in electric vehicles with reduced sensor requirement

This study presents a newly integrated converter for plug-in electric vehicles. The proposed structure achieves various modes of vehicle operation (plug-in charging or power factor correction (PFC), propulsion and regenerative braking). Moreover, a non-linear carrier control method is used for PFC operation which saves the voltage sensor requirement for continuous conduction mode of operation. Reduction of feedback circuitry enhances the compactness of the converter, making it more suitable for on-board charger. Stress and loss analyses and selection of passive components of the converter have been investigated for each mode. Simulation and experimental results show the validity of the proposed converter.

An integrated grid-connected system for multi-port energy processing by microcontroller

The requirement for converters to process different kinds of energy has been urgent. Developing new type of power converter to deal with multi-port energy therefore becomes much more important than before. In this paper a multi-port single-stage converter (MPSSC) is proposed, which is an integrated system (IS) and can handle power direction among battery bank, AC mains and LED load. Even though the MPSSC processes three ports, its main power stage is a single-stage configuration instead of the combination of multiple converters. That is, it can process power effectively and more easily comply with industry standards. The MPSSC is mainly derived from a single-ended primary-inductance converter (SEPIC) incorporating interleaved structure. While the MPSSC draws energy from utility to charge battery bank and/or powers DC load, it is able to perform power factor correction (PFC) over universal line input. In the case of power failure, the MPSSC can instantaneously change energy direction and then discharges the battery so as to power load consecutively. The integrated system of MPSSC is analyzed theoretically. In addition, a 200-W microcontroller-based prototype is built to validate the converter with practical measurements.

A New Bridgeless High Step-up Voltage Gain PFC Converter with Reduced Conduction Losses and Low Voltage Stress

Bridgeless power factor correction (PFC) converters have a reduced number of semiconductors in the current flowing path, contributing to low conduction losses. In this paper, a new bridgeless high step-up voltage gain PFC converter is proposed, analyzed and validated for high voltage applications. Compared to its conventional counterpart, the input rectifier bridge in the proposed bridgeless PFC converter is completely eliminated. As a result, its conduction losses are reduced. Also, the current flowing through the power switches in the proposed bridgeless PFC converter is only half of the current flowing through the rectifier diodes in its conventional counterpart, therefore, the conduction losses can be further improved. Moreover, in the proposed bridgeless PFC converter, not only the voltage stress of power switches is lower than the output voltage, but the voltage stress of the output diodes is lower than the conventional counterpart. In addition, this proposed bridgeless PFC converter features a simple circuit structure and high PFC performance. Finally, the proposed bridgeless PFC converter is analyzed and designed in the discontinuous conduction mode (DCM). The simulation results are presented to verify the effectiveness of the proposed bridgeless PFC converter.

An Active Partial Switching Method in Tertiary Loop for a High-Efficiency Predictive Current-Mode Control PFC Converter

This paper proposes a novel active partial switching method for a boost power factor correction (PFC) converter, based on the predictive current mode control to achieve both current shaping capability and high power conversion efficiency. This method consists of a controller that maintains a switching stop angle near the peak voltage of the input voltage by means of output voltage control, and an adaptive current shaper that adjusts the switching stop period near the zero voltage of the input voltage based upon the load condition. The proposed method shows good PFC performance and high efficiency even under various disturbances such as input voltage and load fluctuations. Moreover, it has the advantage that it is possible to achieve high efficiency even under conditions of output voltage exceeding the peak value of the input voltage. For sequential explanation, this paper illustrates the design of the controller based on the frequency-domain response and provides theoretical analysis of the proposed method. Finally, to verify the effectiveness of the proposed method, experimental results are presented based upon a 2.4 kW boost PFC converter prototype.