Variable on‐time controlled boundary conduction mode single‐ended primary inductor converter power factor correction converter

Abstract

A variable on-time (VOT) control strategy for boundary conduction mode (BCM) single-ended primary inductor converter (SEPIC) power factor correction (PFC) converter with high power factor (PF) and low total harmonic distortion (THD) is proposed. By utilising output voltage and input voltage to modulate the turn-on time of the switch of BCM SEPIC PFC converter, the unity PF and lower THD can be achieved. The operating principles of the VOT controlled BCM SEPIC PFC converter are analysed. The experimental results based on 100 W prototype demonstrate that the PF and THD of proposed VOT controlled BCM SEPIC PFC converter are better than those of traditional BCM SEPIC PFC converter.

GaN-Based ZVS Bridgeless Dual-SEPIC PFC Rectifier With Integrated Inductors

“…Based on (25), it shows that the equivalent inductance of the input inductor L in_eq can be enlarged several times over the self-inductance L in_self when the self-inductance This article has been accepted for publication in a future issue of this journal, but has not been fully edited. Content may change prior to final publication.…”

“…1 (b) [19]- [21] and Fig. 1(c) [18], [25]- [27] are two typical types bridgeless SEPIC PFC topologies. Without the forward bridge rectifier, it allows the current to flow through a minimum number of semiconductor devices.…”

Electronic resistor emulators for ferroresonance damping in MV transformers

“…where, due to the absence of a voltage control loop, the instantaneous output voltage values depend on the open-delta voltage, the emulated resistance and the selected C o and R L . Assuming that the resistor emulator achieves the ferroresonance damping at the AC side, the resistor emulator behaviour can be approximated by v Δ (t) ≃ V^Δ e −(t /(T d /4)) sin 2π where it is considered that the main component in (1), at 2π/T FR rad/s, is damped in T d and the emulated resistance is modelled with (25). The behaviour of the applied emulated damping resistance, controlled with g c (t), is characterised by means of R 1 , R 2 and T. Time-invariant R d ′ corresponds to T → ∞ and timevariant R d ′, according to the proposed g c (t) = G c + k G v Δ (t), is modelled by adjusting R 1 , R 2 and T. By substituting (24) and (25) into (23), the output voltage results in (see (26)) .…”

“…Alternatively to the strategies found in the literature, this paper explores the applicability of well known power converter stages, i.e. [21][22][23][24][25], loss-free resistor (LFR) emulators for the mitigation of ferroresonances in MV VTs (Fig. 1f).…”

Novel distortionless dimming in high power LED lighting using isolated SEPIC converter

“…A non‐isolated SEPIC‐based LED power supply operating in critical conduction mode (CrCM) is reported in the literature [22]. A variable on time controlled SEPIC with high PF and low THDi is also reported under boundary conduction mode in [23]. A bridgeless PFC SEPIC is reported with zero voltage transition mode [24].…”