Power Factor Correction Control Research Articles

Single Power-Conversion AC--DC Converter With High Power Factor and High Efficiency

This paper proposes a single power-conversion ac-dc converter with high power factor and high efficiency. The proposed converter is derived by integrating a full-bridge diode rectifier and a series-resonant active-clamp dc-dc converter. To obtain a high power factor without a power factor correction circuit, this paper proposes a novel control algorithm. The proposed converter provides single power-conversion by using the novel control algorithm for both power factor correction and output control. Also, the active-clamp circuit clamps the surge voltage of switches and recycles the energy stored in the leakage inductance of the transformer. Moreover, it provides zero-voltage turn-on switching of the switches. Also, a series-resonant circuit of the output-voltage doubler removes the reverse-recovery problem of the output diodes. The proposed converter provides maximum power factor 0.995 and maximum efficiency of 95.1% at the full load. The operation principle of the converter is analyzed and verified. Experimental results for a 400 W ac-dc converter at a constant switching frequency of 50 kHz are obtained to show the performance of the proposed converter.

Digitally controlled boost PFC converters operating with large scale load fluctuations

When boost power factor correction (PFC) circuit works with large scale load fluctuations, it is easy to cause a higher total harmonic distortion and a lower power factor because of traditional controllers and inductor current mode. To solve this problem, this paper proposes a PFC control system, which can operate with load fluctuations up to 1 000 W by using duty cycle feed-forward control theory to achieve smooth switching mode. The duty cycles in the next period of the control system are pre-estimated in the current cycle, which enhances the speeds of AD samplers and switching frequency, and reduces the cost and volume of the equipment to some extent. Introductions of system decoupling and feed-forward of input-voltage greatly improve the system performance. Both theoretical simulation and experimental results prove the advantage of the proposed scheme.

Contribution to digital power factor correction controllers in high intensity discharge lamps electronic ballast applications

Utility voltage fluctuations not compensated by the low-frequency voltage loop of the power factor correction (PFC) stage cause a perceptible variation in the light emitted by lamps, unpleasant for the human eye and known as flicker effect. A novel extension of the digital control for PFC stages analyses the input voltage, detects the fluctuations in the range of human flicker sensitivity and modifies the PFC output voltage controller to avoid their propagation to the DC bus. The purpose of the controller is to make the PFC compatible with any second stage lamp driver, assuring the mitigation of the lamp light variation caused by utility disturbances in consistent with the human eye perception. The controller is implemented in a field programmable gate array. A constant lamp luminance is achieved with this digital controller with no dependence on the next ballast stage.

Modeling and PID Control of Single Switch Bridgeless SEPIC PFC Converter

This paper proposes the modeling of Single Ended Primary Inductor Converter (SEPIC) for Power Factor Correction (PFC) and PID control for the converter using various tuning methods. The SEPIC is capable of operating from an input voltage that is greater or less than the regulated output voltage. A small signal dynamic model for SEPIC PFC converter is obtained using state space averaging technique which provides a fifth order transfer function. The complete model of the converter is simulated using MATLAB (SIMULINK). Then the PID controller is designed for the SEPIC PFC converter and various tuning methods were adopted using SISO tool in MATLAB.

PMSM Drive Fed by Sliding Mode Controlled PFC Boost Converter

In this study, a vector controlled permanent magnet synchronous motor (PMSM) drive fed by a two-level inverter which is connected to a boost converter with sliding mode control (SMC) for power factor correction (PFC) is presented. The performance of the drive system is analyzed with all the system details such as speed control of PMSM, SMC, and PFC. The simulation results are obtained using MATLAB/SimPowerSystem blocks. The waveforms of source and motor currents are analyzed with their harmonic spectrum. The unity power factor is performed by obtaining a low input current with total harmonic distortion (THD). The experimental results of PFC are analyzed with input current waveforms and THD values for with/without PFC.

A NOVEL CRM PFC CONTROL METHOD FOR REDUCING INDUCTOR

A novel control method for the critical conduction mode (CRM) power factor correction (PFC) converter is presented, which reduces the size of the boost inductor in the system with wide input-voltage range and improves the efficiency of the system with low input voltage. By introducing the following boost circuit, the output voltage in the application circuit varies with the input root mean square (RMS) voltage to reduce the demand for the large size of the inductor and the efficiency of the system keeps high under the low input voltage. A novel CRM PFC control system with smaller size inductor and higher efficiency is achieved by applied the following boost method to the core control circuits. Experiment results show that the inductance value of the boost inductor is 430 μH using the presented PFC control system and 700 μH using the traditional PFC control system when the input voltage varies from 85 V to 265 V. The novel control method decreases the inductor's value at 38.2%, and the efficiency of the system improves at 1.62% under the input voltage of 85 V.

고역률을 갖는 단일 전력변환 AC-DC 컨버터

This paper proposes a single power-conversion ac-dc converter with a dc-link capacitor-less and high power factor. The proposed converter is derived by integrating a full-bridge diode rectifier and a series-resonant active-clamp dc-dc converter. To obtain a high power factor without a power factor correction circuit, this paper proposes a suitable control algorithm for the proposed converter. The proposed converter provides single power-conversion by using the proposed control algorithm for both power factor correction and output control. Also, the active-clamp circuit clamps the surge voltage of switches and recycles the energy stored in the leakage inductance of the transformer. Moreover, it provides zero-voltage turn-on switching of the switches. Also, a series-resonant circuit of the output-voltage doubler removes the reverse-recovery problem of the output diodes. The proposed converter provides maximum power factor of 0.995 and maximum efficiency of 95.1% at the full-load. The operation principle of the converter is analyzed and verified. Experimental results for a 400W ac-dc converter at a constant switching frequency of 50kHz are obtained to show the performance of the proposed converter.

A current sensorless power factor correction control for LED lamp driver

This paper proposes a new control technique to achieve a unity power factor at the input AC supply for light-emitting diode (LED) lamps controlled by AC–DC converter, without using a current sensor. Only two analog to digital converters (ADCs) for measuring the input and output voltages are used. This technique achieves isolation between power circuit and controller; it can be implemented by using a zero-crossing processing, which has a greater accuracy than other techniques. Simulation and experimental results illustrate the effectiveness and feasibility of the proposed control technique, which achieves low harmonic contents in the supply current, a near unity power factor (PF), a sinusoidal current waveform, and a fast dynamic response under transient operation.

An Off-line Battery Charger based on Buck-boost Power Factor Correction Converter for Plug-in Electric Vehicles

This paper presents an off-line battery charger based on the buck-boost power factor correction (PFC) converter for plug-in electric vehicles (EV). The integrated battery charger is obtained from the traditional three-phase voltage source inverter (VSI) for EV, which operates as buck-boost converter with power factor correction ability. The PFC controller is regulates the battery voltage and controls the supply current of the converter to achieve unity power factor which is very simple and gives good performance. The proposed buck-boost PFC converter is operating in buck mode and boost mode, which is alternatively carried out according to the relationship between the rectified input voltage and battery voltage. The practicality and performance of the battery charger of the proposed converter topology has been verified via simulation.

Operating Three Phase Induction Motor Using Power Factor correction and controlled Technique

This paper presents power factor correction control for three phase induction motor drive using pulse width modulation current controlled technique and also presents a topology for driving a three-phase induction motor with a single-phase ac supply. Single phase boost DC-DC converter is used to obtain near unity and to reduce harmonic distortion in the main supply. In the proposed scheme, UC3854 power factor corrector is used to improve the power factor and dsPIC30F2010 controller is used to generate PWM signals. A three phase, 415V, 1.5hp induction motor is used as load for testing the developed hardware. Textronics TDS2024B storage oscilloscope is used to store the gate pulses and waveforms. The experimental result showed that power factor has increased for all the loads when power factor correction (PFC) technique is used and when compared to without power factor correction (PFC) technique.

Embedded controlled power factor correction zeta converter fed permanent magnet brushless DC motor for mining applications

ABSTRACTDigital simulation and implementation of a power factor correction (PFC) zeta converter based adjustable speed controlled voltage source inverter (VSI) fed permanent magnet brushless DC (PMBLDC) motor for mining application is presented in this paper using low cost embedded controller. The main attractive feature of the zeta converter is that it has a naturally isolated structure, which allows a regulated output voltage with only one power processing stage. The VSI is used as an electronic commutator for the motor. This drive ensures high power factor at the input side. The speed control scheme has the concept of DC-link voltage control proportional to the desired speed of the PMBLDC motor. The speed is regulated by a proportional-integral controller. The proposed PFC zeta converter based PMBLDC motor drive is designed, modelled and simulated using MATLAB/Simulink environment. The results of PFC zeta converter system are compared with the results of VSI-fed PMBLDC drive with L-filter and T-filter at the input side. The power factor is found to have improved using zeta converter. The hardware is implemented using reduced cost embedded controller with zeta converter as PFC converter. Merits of the proposed power converter include improved power factor, less harmonic content and simplified control strategy. The experimental results are compared with the simulation results.

A Nonlinear Controller Based on a Discrete Energy Function for an AC/DC Boost PFC Converter

AC/DC converter systems generally have two stages: an input power factor correction (PFC) boost ac/dc stage that converts input ac voltage to an intermediate dc voltage while reducing the input current harmonics injected to the grid, followed by a dc/dc converter that steps up or down the intermediate dc-bus voltage as required by the output load and provides high-frequency galvanic isolation. Since a low-frequency ripple (second harmonic of the input ac line frequency) exists in the output voltage of the PFC ac/dc boost converter due to the power ripple, the voltage loop in the conventional control system must have a very low bandwidth in order to avoid distortions in the input current waveform. This results in the conventional PFC controller having a slow dynamic response against load variations with adverse overshoots and undershoots. This paper presents a new control approach that is based on a novel discrete energy function minimization control law that allows the front-end ac/dc boost PFC converter to operate with faster dynamic response than the conventional controllers and simultaneously maintain near unity input power factor. Experimental results from a 3-kW ac/dc converter built for charging traction battery of a pure electric vehicle are presented in this paper to validate the proposed control method and its superiority over conventional controllers.

92% High Efficiency and Low Current Mismatch Interleaving Power Factor Correction Controller With Variable Sampling Slope and Automatic Loading Detection Techniques

This paper proposes the dual nondeadtime variable sampling slope technique to carry out precise phase sensing and suppress phase error in interleaving power factor correction (PFC) controller over a whole ac switching cycle for low current mismatch. Furthermore, the proposed automatic loading detection (ALD) technique can keep efficiency higher than 92% over a wide load range due to accurately controlling the ON/OFF of dual phases. The test circuit fabricated in the TSMC 0.5-μm 800-V UHV process shows that the highly integrated interleaving PFC can deliver a high power of 180 W and a high efficiency of 95% at an output power of 180 W.

An Integrated Implementation of Two-Phase Interleaved PFC and Dual Motor Drive Using Single MCU With CLA

Heating ventilation and air conditioning (HVAC) drives utilize variable speed control to maximize efficiency. Power factor correction (PFC) stage is used in the rectifier design in these applications to comply with regulations, such as IEC 61000-3-2, which limit the input current harmonics. Typically control of PFC and the motor stage is kept separate, due to limited CPU bandwidth, where fast is desired for PFC stage (up to 200 kHz) and motor inverter (10-20 kHz). This paper presents a MCU with control law accelerator (CLA) architecture, which enables integration of dual motor control and PFC on a single controller, for a cost sensitive application such as HVAC. In addition to cost reduction and performance improvement, the integration enables the control of the stages together. Also, the surplus bandwidth provided by the CLA, allows the execution of slow background tasks, diagnostics and communication. Integration challenges with software and system level details for the proposed solutions are highlighted in the paper. Additionally improvements to the PFC algorithm using a nonlinear control technique for better output voltage control under dynamic load conditions are presented.

입력전압을 감지하지 않는 전류연속/임계동작모드 Active Power Factor Correction Circuit

본 논문에서는 입력전압을 감지하지 않는 전류연속/임계동작모드 active power factor correction(PFC) circuit을 제안하였다. 기존의 입력전압을 감지하지 않는 PFC circuit의 경우 출력전류가 낮은 경 부하 조건에서 DCM 동작을 수행하고, 이에 따라 PF가 감소하는 문제가 발생한다. 제안한 PFC circuit은 70KHz의 주파수로 CCM 동작을 수행하고, 경 부하 조건에서 최대 200KHz까지 스위칭 주파수가 가변되는 CRM 동작을 수행하도록 하였다. 이를 통해 경 부하 조건에서 PF가 감소하는 문제를 해결하였다. PFC controller IC는 0.35μm BCDMOS 공정을 이용하여 제작하였으며, 240W급 PFC prototype을 제작하여 실험하였다. 제안한 PFC circuit은 기존의 PFC circcuit 대비 최대 10%의 역률이 향상되었고, IEC 61000-3-2 Class D 규격에 따른 경 부하 조건에서는 최대 4% 역률이 향상되었다.

Triple Loop Modulation (TLM) for High Reliability and Efficiency in a Power Factor Correction (PFC) System

The proposed triple loop modulation (TLM) can ensure reliability of the power factor correction (PFC) system due to the improvement of transient response. In conventional design, low bandwidth of less than 20 Hz that rejects ac source of 60/120 Hz coupling deteriorates system reliability in case of output load variation. Contrarily, the proposed TLM can automatically adjust bandwidth to rapidly increase or decrease inductor current to shorten transient response time. Besides, in the steady state, system stability can be guaranteed by low-frequency compensation pole without being affected by the TLM. The test circuit fabricated in a VIS 500 V UHV laterally diffused metal-oxide-semiconductor transistor process demonstrates that the highly integrated PFC controller with the proposed TLM has high power factor of 99%, high efficiency of 95%, and high power driving capability of about 90 W. The improvement in transient response is twofold faster than in conventional PFC design with output load variation from 90 to 20 W and vice versa.

Analysis and design of reduced‐order sliding‐mode controller for three‐phase power factor correction using Cuk rectifiers

In this study, the analysis and design of reduced-order sliding-mode controller (ROSMC) for power factor correction (PFC) in a three-phase system is presented. A new and systematic technique for the selection of sliding surface co-efficients to implement ROSMC is attempted. The front end is a three-phase diode rectifier followed by DC–DC Cuk converter modules with the common DC output. Instantaneous symmetrical component theory is used for reference current generation. The control strategy uses three inner ROSMC current controllers for source current shaping and an outer voltage loop using proportional integral controller for load voltage regulation. The proposed method offers simple control strategy, fast transient response and power factor close to unity. To validate the proposed method, a prototype controlled by dSPACE 1104 signal processor is set up. Simulation and experimental results indicate that the proposed system offers regulated output voltage for wide load variations and power factor close to unity.

Storage Capacitance Minimization In Led Drivers Based On Photometrical Constraints And Converter Integration


 This work proposes a novel combined approach for reducing the storage capacitances in off-line high power factor LED drivers. The proposal is to combine converter integration (power factor correction plus power control stages sharing a common switch) with photometrical constraints on the maximum allowable LED current ripple. An experimental setup was used to assess the upper limit for current ripple on the LEDs based on luminous flux drop, efficacy drop and chromaticity coordinate change. By combining the ripple design constraint obtained from photometrical measurements with the design methodology of an integrated converter, the largest storage capacitances (bus and output capacitors) were greatly reduced, allowing the use of small film capacitors of long lifespan, rather than relying on large short-lived electrolytic capacitors. As a design example, an integration between a SEPIC power factor preregulator and a buck-boost power control stage was chosen and a prototype was built, fed from 220 V / 60 Hz mains voltage and feeding 56 series-associated LEDs (ca. 70 W). The driver imposed a 50% current ripple on the LEDs, value for which it was found to yield only 0.2% decrement in luminous flux, while preserving color stability.

Improved Power Quality IHQRR-BIFRED Converter Fed BLDC Motor Drive

This paper presents an IHQRR (Integrated High Quality Rectifier Regulator) BIFRED (Boost Integrated Flyback Rectifier Energy Storage DC-DC) converter fed BLDC (Brushless DC) motor drive. A reduced sensor topology is derived by utilizing a BIFRED converter to operate in a dual DCM (Discontinuous Conduction Mode) thus utilizing a voltage follower approach for the PFC (Power Factor Correction) and voltage control. A new approach for speed control is proposed using a single voltage sensor. The speed of the BLDC motor drive is controlled by varying the DC link voltage of the front end converter. Moreover, fundamental frequency switching of the VSI's (Voltage Source Inverter) switches is used for the electronic commutation of the BLDC motor which reduces the switching losses in the VSI. The proposed drive is designed for a wide range of speed control with an improved power quality at the AC mains which falls within the recommended limits imposed by international power quality standards such as IEC 61000-3-2.

A Novel Three-Phase Power Factor Correction with Digital Control

A new three-phase power-factor-correction (PFC) scheme is discussed using two single phase power factor correction circuit parallel connected. Two phase orthonormal voltage is produced by means of a auto transformer from a three phase input,fluctuation of neutral point by three single phase power-factor-correction circuit parallel connected is canceled,coupling interference is reduced among three phases,digitally controlled Power Factor Correction Boost Converters is adapted,input current wave sine with unity power factor suppress the secondary harmonic of input AC side is realized,voltage and low current stresses across each switch are reduced. Simulation and experimental results prove that it can achieve high power factor,low current,good capability of anti-interference and high reliability.