This paper presents the comparison of various current control strategies employed for an interleaved power factor correction (PFC) boost converter for improving the power quality. The major control strategies discusse...This paper presents the comparison of various current control strategies employed for an interleaved power factor correction (PFC) boost converter for improving the power quality. The major control strategies discussed in this paper are: peak current control, average current control, hysteresis control, borderline current control and non-linear control. These strategies are implemented in MATLAB/SIMULINK and the performance of the proposed converter is compared under open loop and closed loop operation. From the results, the input current waveform was close to input voltage waveform implying improved power factor and reduced total harmonic distortion for nonlinear current control technique. Experimental results validate the proposed method.展开更多
This paper presents a power factor corrected (PFC) new bridgeless (BL) Cuk Topologies for low power applications. A BL configuration of Cuk converter is proposed which eliminates the usage of diode bridge rectifier at...This paper presents a power factor corrected (PFC) new bridgeless (BL) Cuk Topologies for low power applications. A BL configuration of Cuk converter is proposed which eliminates the usage of diode bridge rectifier at the front end of the PFC converter, thus reducing the switching and conduction losses coupled with it. This new BL Cuk converter has two semiconductors switches. The current flow during each switching cycle interval of the converter reduces the conduction losses compared to the conventional Cuk PFC converter. It also reduces the input current ripple and Electromagnetic Interference (EMI). The inrush current during the starting period is limited and the input, output currents of the converter are continuous with minimum current ripple. Hence it is preferred mostly compared to other PFC circuits. The proposed topology works in the Discontinuous Conduction Mode (DCM) with simple control circuitry to achieve almost a unity power factor with less distortion in the input AC current. The switching of the power switches is done under zero current. The proposed PFC topologies are theoretically investigated and performance comparisons are made with the conventional rectifiers. The proposed PFC converter is simulated in MATLAB/SIMULINK with Fuzzy Logic Controller (FLC) and results are demonstrated to evaluate the effectiveness of the controller.展开更多
由于统一潮流控制器的广泛应用受制其可靠性及成本高昂等不足,分布式潮流控制器(unified power flow controller,DPFC)应运而生。为分析DPFC提升最大输电能力期望和供电可靠性的效能,需要将该装置纳入大电网可靠性评估中。针对其分布...由于统一潮流控制器的广泛应用受制其可靠性及成本高昂等不足,分布式潮流控制器(unified power flow controller,DPFC)应运而生。为分析DPFC提升最大输电能力期望和供电可靠性的效能,需要将该装置纳入大电网可靠性评估中。针对其分布式串联侧进行结构解析,从而确定DPFC的运行状态及空间转移模型,通过马尔科夫过程可求解出DPFC各状态平稳概率与故障/修复率。基于此,建立含DPFC的系统潮流计算模型,并提出从断面最大输电能力期望和供电可靠性两大角度来综合评价DPFC效能的研究方法。经IEEE-RTS79算例分析表明:所述方法能够有效评价DPFC在电网可靠性方面的改善能力,可以从可靠性角度来确定DPFC最优配置方案,从而为实际工程提供一定指导意义。展开更多
文摘This paper presents the comparison of various current control strategies employed for an interleaved power factor correction (PFC) boost converter for improving the power quality. The major control strategies discussed in this paper are: peak current control, average current control, hysteresis control, borderline current control and non-linear control. These strategies are implemented in MATLAB/SIMULINK and the performance of the proposed converter is compared under open loop and closed loop operation. From the results, the input current waveform was close to input voltage waveform implying improved power factor and reduced total harmonic distortion for nonlinear current control technique. Experimental results validate the proposed method.
文摘This paper presents a power factor corrected (PFC) new bridgeless (BL) Cuk Topologies for low power applications. A BL configuration of Cuk converter is proposed which eliminates the usage of diode bridge rectifier at the front end of the PFC converter, thus reducing the switching and conduction losses coupled with it. This new BL Cuk converter has two semiconductors switches. The current flow during each switching cycle interval of the converter reduces the conduction losses compared to the conventional Cuk PFC converter. It also reduces the input current ripple and Electromagnetic Interference (EMI). The inrush current during the starting period is limited and the input, output currents of the converter are continuous with minimum current ripple. Hence it is preferred mostly compared to other PFC circuits. The proposed topology works in the Discontinuous Conduction Mode (DCM) with simple control circuitry to achieve almost a unity power factor with less distortion in the input AC current. The switching of the power switches is done under zero current. The proposed PFC topologies are theoretically investigated and performance comparisons are made with the conventional rectifiers. The proposed PFC converter is simulated in MATLAB/SIMULINK with Fuzzy Logic Controller (FLC) and results are demonstrated to evaluate the effectiveness of the controller.
文摘由于统一潮流控制器的广泛应用受制其可靠性及成本高昂等不足,分布式潮流控制器(unified power flow controller,DPFC)应运而生。为分析DPFC提升最大输电能力期望和供电可靠性的效能,需要将该装置纳入大电网可靠性评估中。针对其分布式串联侧进行结构解析,从而确定DPFC的运行状态及空间转移模型,通过马尔科夫过程可求解出DPFC各状态平稳概率与故障/修复率。基于此,建立含DPFC的系统潮流计算模型,并提出从断面最大输电能力期望和供电可靠性两大角度来综合评价DPFC效能的研究方法。经IEEE-RTS79算例分析表明:所述方法能够有效评价DPFC在电网可靠性方面的改善能力,可以从可靠性角度来确定DPFC最优配置方案,从而为实际工程提供一定指导意义。