Analysis of Bridgeless PFC Rectifier using MATLAB-SIMULINK

Abstract

This paper analyses a bridgeless PFC converter using MATLAB-SIMULINK . The PFC Converter used in this paper works on discontinuous mode, active power factor correction (PFC) techniques are becoming necessary for the electronic equipment to meet harmonic regulations and standards . Here a single phase PFC rectifier is analysed , it has less number of components count, higher power density and less conduction losses . Open loop and closed loop simulation results are provided to verify the performance. KEYWORDS:Bridgeless resonant PFC rectifier , Power factor correction , Single phase rectifier ,Total harmonic distortion(THD). I.INTRODUCTIONAccording to the demand on high efficiency and low harmonic pollution, the active power factor correction (PFC) circuits are commonly employed in ac-dc converters and switched-mode power supplies. Generally, these converters include a full-bridge diode rectifier on an input current path so that conduction losses on the full-bridge diode occur and it will be worse especially at the low line. To overcome this problem, bridgeless converters have recently been introduced to reduce or eliminate the full-bridge rectifier, and hence their conduction losses. Most of the conventional proposed bridgeless PFC converters have at least one of the following drawbacks-high components count, components are not fully utilized over whole ac-line cycle, complex control, lack of galvanic isolation due to the floating ground, some topologies require additional diodes and/or capacitors to minimize EMI.In this paper, the converter operate in resonant mode to obtain an automatic PFC close to unity in a simple manner. The resonant mode operation have zero-current turn-on in the active power switches, zero-current turn-off in the output diode and this reduces the complexity of the control circuitry. The advantages of the converter is less number of components, low switching losses, high efficiency etc. Open loop simulation and closed loop simulation are provided in this report for performance evaluation.Next section discusses the principle of operation of proposed Bridgeless PFC converter and also its modes of operation. Third section deals with the closed loop and open loop simulation diagrams and results. Fourth section concludes the topic. II.LITEARTURE SURVEYPower factor correction is important in switched mode power supplies. Most of the PFC rectifier include a boost/buckboost topology converter at their front end due to its high power factor (PF) capability. The major disadvantage of the conventional PFC converters is its lower efficiency due to significant losses in the diode bridge. In order to reduce these problem, an efficient bridgeless PFC circuit topologies were developed..Bu t these bridgeless PFC topologies also have some following drawbacks like high components count, components are not fully utilized over whole ac-line cycle, complex control, dc output voltage is always higher than the peak input voltage, lack of galvanic isolation, and due to the floating ground, some topologi...