Research On One Circuit Of Single-phase Three-level Power Factor Correction

The rapid development of electronic technology has brought us not only a great convenience, but also brought some new problems. For example, the power electronic devices convert AC into DC generally used the diode rectifier, so the input current includes a large number of harmonic components. In order to solve the harmonic pollution of rectifier circuit in the power electronic devices, we must reduce the THD of input current in rectifier, increase its power factor. To reduce the THD of the input current, we use passive or active PFC technology generally, active power factor correction technology more pronounced because of better performance.In this paper, at first, the principle Boost PFC circuit and several major control theories is introduced in the power electronic devices. Because of voltage step-up features in Boost circuit, the voltage of switch in Boost PFC circuit is generally more high, in order to reduce the voltage stress of switch and the loss, a single-phase three-level Boost PFC circuit is studied in this paper, there are two switches and two DC capacitors in the single-phase three-level when it is one in the general Boost PFC circuit. This paper analysis the principle of the main circuit based on the on-off of two switches, circuit switch-off of, and describe the control theory based on the average current control method. Through the principle of circuit simulation on Matlab software, it is tested and verified that the circuit can reduce the THD of input current, make power factor close to 1, and reduce the voltage of each switch to half of the output voltage by controlling the turn on-off of the two switches. Then the main circuit and control circuit are designed based on the principle of circuit, and it is tested and verified that the principle of the main circuit and control method of this single-phase three-level Boost PFC circuit is reasonable and feasible by the experimental.