High-Efficiency Interleaved Totem-Pole PFC Converter With Voltage Follower Characteristics
Jefferson Wilhelm Meyer Soares, Alceu André Badin
Abstract
High power density, efficiency, control simplification, and robustness are highly demanded for power factor correction (PFC) converters. This article proposes a totem-pole rectifier based on the switching cell with switching frequency modulation (SC-SFM). The SC-SFM features interleaved operation, soft commutation, and resistive characteristics with continuous conduction in the input inductor. The converter operates without needing sensors and a control loop for the current. Unlike conventional solutions or some sensorless converters, the converter does not require a fast control loop to shape the current since the current naturally follows the input voltage. Only one output voltage sensor and one input half-line cycle detector are required to achieve unitary power factor (PF) and regulated dc output voltage. A detailed analysis of the converter operation, including the operating principle, mathematical analysis, a small signal model, and control method, is presented, including the differences in operation from the conventional PFC rectifier with the diode bridge. Experimental results evaluate a 1-kW prototype with different switch technologies [insulated-gate bipolar transistor (IGBT), silicon carbide (SiC), and gallium nitride (GaN)].