Boost power factor correction converter with adaptive harmonic compensation control

The operation of the two-phase interleaved CRM Boost power factor correction (PFC) converter with coupled inductors is analyzed in this paper. Since the equivalent inductance varies with the switching mode and duty cycle, the current mode control method should be adopted to achieve PFC rather than the voltage mode control. The switching frequency is derived, and the self inductance is discussed in term of the minimum switching frequency, which should be higher than 20 kHz to avoid acoustic noise. The design methodology of the coupled inductors is presented as well. Compared to the discrete inductors, the coupled inductor has small size and low copper usage, so the power density of the PFC converter can be increased.

Buck-buck/Boost power factor correction (PFC) converter is a great choice to compensate the inherent dead zones in the input current of buck PFC converter. However, whether the converter operates with traditional constant on-time control in critical conduction mode (CRM) or with conventional constant duty-cycle control in discontinuous conduction mode (DCM), the power factor (PF) is low, especially at low input voltage. Therefore, fixed on-time ratio control (FOTRC) and fixed duty-cycle ratio control (FDCRC) are proposed for CRM/DCM buck-buck/boost PFC converter to achieve high PF, respectively. Both control methods maximize PF over wide input voltage range by adjusting on-time or duty-cycle of buck/boost mode and buck mode. Compared with the traditional controls, the proposed control methods also have advantage of increasing efficiency. Furthermore, for improving dynamic response performance, smooth and rapid dynamic response control (SRDRC) is put forward, which can reduce the regulation time and output voltage overshoot/undershoot when the load or input voltage changes abruptly. In addition, the implementation circuits combining FOTRC/FDCRC and SRDRC are designed. Two prototypes have been built and tested in the lab to demonstrate the validity of the theoretical analysis.

Dynamic response of boost power factor correction (PFC) converter operating in continuous-conduction mode (CCM) is heavily influenced by low-bandwidth of voltage control loop. A novel tri-state boost PFC converter operating in pseudo-continuous-conduction mode (PCCM) is proposed in this paper. An additional degree of control-freedom introduced by a freewheeling switching control interval helps to achieve PFC control. A simple and fast voltage control loop can be used to maintain a constant output voltage. Furthermore, compared with boost PFC converter operating in conventional discontinuous-conduction mode (DCM), boost PFC converter operating in PCCM demonstrates greatly improved current handling capability with reduced current and voltage ripples. Analytical and simulation results of the tri-state boost PFC converter have been presented and compared with those of the boost PFC converter operating in conventional CCM and DCM. Simulation results show excellent dynamic performance of the tri-state boost PFC converter.

The switching frequency of the boost power factor correction (PFC) converter operating in critical conduction mode (CRM) varies in a line cycle, making the conducted electromagnetic interference (EMI) spectra of the converter appear great differences under different input voltage and load conditions. The EMI filter should be designed according to the worst conducted EMI spectrum of the converter, so as to suppress the conducted EMI of the converter to be lower than the standard limits under all working conditions. This paper analyzes the characteristics of the common-mode (CM) and differential-mode (DM) noise spectra of the CRM boost PFC converter, and discusses the effects of the varied switching frequency on the peak, quasi-peak (PK), and average (AV) conducted EMI spectra. It is revealed that, for the conducted EMI limits defined in EN55022 class B, which are specified within 150 kHz to 30 MHz, the EMI filters required for suppressing the QP spectra of the conducted EMI of the CRM boost PFC converter are larger than that for suppressing the AV spectra, and the QP values of the conducted EMI under all working conditions are lower than a certain maximum boundary. The input voltage and load conditions for the worst CM and DM noise spectra of the converter are derived in this paper, thus the repetitive measurements and numerical calculations are avoided. A CRM boost PFC converter prototype is fabricated, and the evaluation of the measured conducted EMI spectra and the EMI filter design example verified the theoretical analysis.

Power Factor Correction (PFC) converter is a key component in modern switching power supplies, while high efficiency and high power density are the main goals of PFC converter. In this paper, taking a single-phase Boost circuit as an example, a PFC converter with 300 kHz switching frequency and 1 kW output power which is based on continuous inductor current (CCM) mode is designed to reduce the volume of the core component and improve the power density of the converter. The paper includes the detailed design of the boost inductor, the analysis of the loss of the inductor at high frequency operation and the loss of the PFC converter. Finite element analysis is used to verify that the winding loss can be reduced by taking multi-strand wire winding. New semiconductor devices CoolMOS and SiC are employed which can reduce the loss effectively. The experimental results are provided which demonstrate that the employ of SiC diode and multi-strand wire winding can enable enhanced performance on efficiency.

The three-level boost power factor correction (PFC) converter has advantages of lower inductor current ripple and lower switch withstanding voltage compared with the boost PFC converter. Interleaved pulsewidth modulation had been used in the multiphase boost PFC converter. In the literature, interleaved current sensorless control (ICSC) for the multiphase boost PFC converters had been proposed. In this paper, the behavior of the three-level boost PFC converter is first analyzed. The results show that three-level converter has the same average equation as the interleaved boost PFC converter. Then, ICSC is modified for the three-level boost PFC converter with considering the voltage imbalance and the zero-crossing current distortion. The proposed modified ICSC (MICSC) is implemented in a field-programmable gate array board. Simulation results and experimental results are also provided to validate the proposed MICSC.

This paper proposes a dual mode used to control a single phase soft switching boost power factor correction Converter (PFC) developed with a new active snubber circuit. The soft switched boost power factor correction converter has merits of less voltage and current stresses, improved efficiency and reduced switching losses. Thus the cost and complexity of the converter is reduced. The dual mode controller combines both continuous conduction mode (CCM) and critical conduction mode (CRM). The simulation results declare high efficiency and optimum power factor for wide range of varying loads.

Nowadays electric vehicles (EVs) are the most popular due to their cost-effectiveness and as an alternative to traditional petroleum fuel-based vehicles. When EV is charged from the utility grid conventional AC-DC converter act as a nonlinear load drawing peaky current from a supply and results in a very poor input power factor. The converter present at the input AC side which converts alternating current (AC) into direct current (DC), a crucial part of an electric car battery charging system, must have high efficiency. The topologies for use at the ac input side to convert ac into dc for EV battery charging are evaluated in this paper. The focus is on boost converter-based power factor correction converters, which provide excellent efficiency, good power factor, and affordable pricing. Traditional boost power factor correction converter, interleaved boost power factor correction converter, and bridgeless totem pole boost power factor correction converter are the topologies under investigation. The performance of all these topologies is simulated using Matlab/Simulink. All converters give the output of 400 V DC from a universal ac input voltage with a Total Harmonic Distortion (THD) percentage level that satisfies the IEEE Standards are provided with their simulation results.

The high frequency capability and low on-state losses of Gallium Nitride (GaN) transistors offer the potential to increase converter efficiency and/or reduce heatsink and passive component size. This paper investigates the use of GaN technology to enhance the performance of power factor correction (PFC) and LLC converters for battery charging applications. First the efficiency performance of non-isolated PFC converters using GaN transistors is compared by simulation, the asymmetric bridgeless PFC converter is shown to achieve the best efficiency, with a predicted figure of 99% in a 1MHz, 200W design. The predictions are validated by an experimental prototype using a GS66502B, GaN Systems E-mode GaN transistor. Then the efficiency comparison of the PFC and LLC converter using GaN devices for battery charging applications is included in the paper. The experimental results of the PFC converter with GaN devices are also included. Additionally, this paper includes the analysis and design of a common mode input filter for the GaN-based high frequency converters for battery charging application. The size of both the converters using GaN devices is reduced by 40% than the converters based on Si devices. The switching loss comparison of GaN and Si devices are also included in the paper.

본 논문에서는 임계전류도통모드로 동작하는 디지털제어 단상 역률개선(PFC; power-factor correction) 컨버터를 제안한다. 제안한 컨버터는 PFC를 위하여 DC-DC 부스트 컨버터 구조를 이용하며 인덕터전류를 임계도통모드로 동작시킨다. 또한 제안한 컨버터는 마이컴을 이용하여 디지털적으로 제어되기 때문에 제어회로는 간단해지고 컨버터는 더욱 효과적으로 동작한다. 본 논문에서는 먼저 제안한 컨버터의 동작원리를 설명하고 회로를 해석한다. 그리고 본 논문은 제안한 컨버터의 구현방법을 소프트웨어와 회로설계 부분으로 구분하여 구체적인 설계예와 함께 설명한다. 또한 설계된 회로파라미터에 의한 프로토타입 컨버터의 실험결과로 제안한 컨버터가 단상 PFC 컨버터로써 좋은 동작 특성을 가지고 있음을 보인다. This paper presents a digital-controlled single-phase power-factor correction (PFC) converter operating in critical current conduction mode. The proposed converter utilizes the DC-DC boost converter topology for the PFC and operates the inductor current in critical conduction mode. Because the proposed converter is controlled digitally using a micom, its control circuit is simplified and the converter operates more effectively. This paper first explains the operational principles of the proposed converter and then analyzes the converter circuit. And this paper explains the implementation method of proposed converter with a detail design example, which is divided into software and circuit design parts. Also, it is shown through the experimental results of the prototype converter by the designed circuit parameters that the proposed converter has good performance as a single-phase PFC converter.

The use of power factor correction (PFC) converters is widely discussed and considered for most off-line power supplies. For low power applications, boost PFC converters operated in discontinuous conduction mode (DCM) or boundary conduction mode (BCM) mode are usually employed. The main advantage of BCM mode is the reduction of reversal recovery loss of diode and simple control, especially at the high-line light-load condition. In this paper, a digital-controlled method for boost PFC operating under boundary conduction mode without input voltage sensing is proposed. The digital PI controller voltage is used to determine the constant on-time period and the comparator block inside the DSP controller is employed to detect the zero-crossing of inductor current for turning on the main switch. Therefore, the size and cost are reduced significantly. A 200W boost PFC prototype is implemented and tested to verify the feasibility of the proposed control scheme.

The authors propose a simple and robust voltage controller to improve voltage dynamics in power factor corrected (PFC) converters. The conventional control of the PFC converters requires filtering of twice-the-line-frequency voltage ripples present on the DC bus voltage to reduce the total harmonic distortion (THD) in the input current. This filtering action significantly reduces the effective voltage regulation bandwidth, resulting in slow voltage dynamics. The proposed scheme cancels the voltage ripple on the DC bus voltage feedback path without any filtering action and thereby allows design of large bandwidth voltage control loop. This eliminates large overshoots and undershoots in output voltage during transients, which are prevalent in conventionally designed PFC converters. The controller design and implementation are described and simulation results are presented for single-phase boost PFC converter as well as single-phase voltage source PFC converter to demonstrate the feasibility of the proposed technique.

This manuscript deals about the configuration of a power factor correction (PFC) converter feeding a drive of brushless DC (BLDC) motor for medium and low power equipment. The front-end PFC converter working in discontinuous inductor current mode (DICM) is applied for regulating the DC link voltage and PFC is achieved inherently. The BLDC motor speed is adjusted by regulating the DC link voltage of voltage source inverter (VSI) feeding to motor. The DC link voltage of drive system is maintained by a single DC voltage actuator. A prototype is developed for evaluating the performances of anticipated drive for the speed control over a broad range. The performance of anticipated drive is also validated for its function at varying AC mains voltages (90V–265V). Test results for power quality (PQ) parameters are compared with restrictions of power quality standard IEC 61000-3-2.

This work proposes a novel approach for managing the output DC link voltage of a single-phase power factor correction (PFC) converter for electric vehicle (EV) charging without using a DC voltage sensor. The inputs and outputs of conventional boost PFC converters normally use several expensive sensors such as input voltage, input current, and output voltage. These sensors are employed to maintain system stability and control the quality of the power. A DC voltage sensorless control utilizing an estimator is used to lower the cost and hardware complexity of the power converter. The output DC link voltage is predicted using the available input voltage and current signals. For a high power factor, the controller follows the reference sine wave signal. Additionally, the converter exhibits extremely steady performance under transient fluctuations in load for a typical 1kW PFC converter. A novel Simplified Optimum Intelligent PID (SOI-PID) controller is designed for a 2.4kW, 400V output voltage, and 6A rated load, based on the second order transfer function of the system, both designs are analyzed, simulated, and compared for the same circuit parameters and loading conditions. The novel SOI-PID controller has shown advantageous performance in both transient and steady-state periods including lower rise and settling times, lower maximum overshoot, fast response to load variation, and lower stress on switching element which leads to better efficiency and lower fixed cost of the overall system.

This paper proposes a new passive snubber cell for an AC-DC power factor correction (PFC) converter circuit suitable for high power applications. The switch is made to turn ON under zero current switching (ZCS) and turn OFF under zero voltage switching (ZVS) conditions by the proposed passive snubber components. The snubber cell comprises of minimum components with load independent operations. The snubber cell is incorporated into the conventional AC-DC boost PFC converter to achieve a good power factor of near unity, regulated output DC voltage, sinusoidal input current, and low voltage and current stress on all the semiconductor components used. In this paper, the simulation results are provided for the proposed converter topology in detail with modes and governing equations.