Study on PFC(Power Factor Correction) Eliminating Their Own Harmonics in the Distributin Power System

各种非线性半导体电路用于消费电子和工业电子。它们几乎都有整流电路。众所周知，这种整流器电路在电力系统中产生各种谐波。因此，随着采用这种整流器的应用的普及，电力系统中谐波的发生可能会增加。由于这种现象，已经提出并研究了用于单相和三相整流器的各种功率因数校正电路。这些方法使用开关器件来尝试将输入电流修改为正弦波形。然而，这些方法可能对成本性能产生不利影响。从这个角度来看，研究不使用开关器件的谐波抑制方法是合适的。本研究探讨各种PFC电路以降低谐波。我们提出了一些新颖的整流电路。这些电路可以在不使用开关器件的情况下实现功率因数校正。由于不使用诸如功率晶体管的开关器件，所以不产生诸如EMI的开关损耗和开关噪声。因为也不需要开关装置的控制电路，所以降低了系统成本。许多作者已经提出了各种无开关器件的PFC电路。然而，如果没有开关器件，在没有Transformer或开关操作的情况下，获得小于输入电源电压的电压有点困难。在变压器的情况下，重量和尺寸的问题是严重的。在此背景下，本研究也探讨并提出新颖的PFC电路，以非常简单的方式产生相应的直流电压。

Various non-linear semiconductor circuits are used in consumer electronics and industrial electronics. They almost all have rectifier circuits. It is well known that such rectifier circuits generate various harmonics in the power system. Hence, with the spread of applications incorporating such rectifiers, the occurrence of harmonics in the power system is likely to increase. Because of this phenomenon, various power factor correction circuits have been proposed and studied for single-phase and three-phase rectifiers. These methods use switching devices to try to modify the input current to a sinusoidal waveform. However these methods can have an adverse effect on the cost performance. From this point of view, it is appropriate to study harmonic reduction methods that work without the use of switching devices. Various PFC circuit to reduce such harmonics have been studied in this research. We have proposed some novel rectifier circuits. These circuits can achieve power factor correction without the use of switching devices. Since switching devices such as power transistors are not used, switching losses and switching noise, such as EMI, are not generated. Because the control circuit for the switching device is also unnecessary, the system cost is reduced. Various PFC circuits without switching devices have been proposed by many authors. Without switching devices, however, it is a little difficult to obtain voltages less than the input supply voltage without a transformer or switching operations. In the case of transformers, the problem of weight and size is serious. With this background, this research also discussed and proposed novel PFC circuits to generate corresponding DC voltages using very simple ways.