A general technique for derivation of average current mode controllaws for single-phase power-factor-correction circuits without inputvoltage sensing

摘要

This paper presents a general technique to derive average currentnmode control (CMC) laws without input voltage sensing to achieve highnpower factor for single-phase topologies operating in continuousnconduction mode (CCM). The control laws are derived based on thensteady-state input-output voltage relationships and the CCM large-signalnaveraged pulsewidth modulation (PWM)-switch model. Using thisnmethodology, average CMC laws with linear PWM waveforms are discoverednfor commonly used single-phase power stage topologies such as boost,nflyback, SEPIC, and buck/boost. Conventional three-loop-controllednaverage CMC converters can now be controlled with a two-loopnarchitecture. Hardware results for a boost power factor correction (PFC)nand simulation results for flyback, SEPIC, and buck/boost topologiesnverify operation. The small-signal models of the current loop andnvoltage loop are derived for the boost topology and are used for controlnloop design. Input current harmonic distortion measurements demonstratenimproved performance compared to the conventional three-loop controlntechnique