Single‐stage single‐switch PFC converter for wide‐input extreme step‐down voltage applications

Abstract

SUMMARYThis paper presents a new single-stage single-switch high power factor correction AC/DC converter suitable for low-power applications (< 150 W) with a universal input voltage range (90-265 V rms ). The proposed topology integrates a buck-boost input current shaper followed by a buck and a buck-boost converter, respectively. As a result, the proposed converter can operate with larger duty cycles compared with the existing single-stage singleswitch topologies, hence, making them suitable for extreme step-down voltage conversion applications. Several desirable features are gained when the three integrated converter cells operate in discontinuous conduction mode. These features include low semiconductor voltage stress, zero-current switch at turn-on, and simple control with a fast well-regulated output voltage. A detailed circuit analysis is performed to derive the design equations. The theoretical analysis and effectiveness of the proposed approach are confirmed by experimental results obtained from a 100-W/24-V dc laboratory prototype.

Step‐up/step‐down DC‐DC converter with near zero input/output current ripples

“…However, the three inductors have identical voltage waveforms; hence, they can be magnetically coupled into a single magnetic core as shown in Figure 7. This is a very attractive feature for power factor correction applications since it will minimize the EMI effect and the input filtering stage [43][44][45][46]. This condition is very desirable, because the generated EMI noise is minimized, dramatically reducing input and output filtering requirements.…”

“…Moreover, the circuit of Figure 7 can supply free ripple current in the input and output inductors not only in CCM but in DCM as well, where the high switching ripple is of concern. This is a very attractive feature for power factor correction applications since it will minimize the EMI effect and the input filtering stage [43][44][45][46]. Figure 7 shows that the input inductor L 1 and the output inductor L 3 are both coupled to L 2 , but that L 1 and L 3 are not directly coupled.…”

Hybrid DC–DC converter with high efficiency, wide ZVS range, and less output inductance

“…The first stage is a single-phase alternating current (AC)-direct current (DC) converter. Boost converters with diode bridge or bridgeless topologies have been discussed in [1][2][3]11] to achieve a stable DC bus voltage, low line harmonic current, and high input power factor. The second stage is a DC-DC converter with high-frequency link for battery current regulation and galvanic isolation.…”

Non‐isolated large step‐down voltage conversion ratio converter with non‐pulsating output current

“…But, the voltage conversion ratio of this converter is not improved, and also, because the switches are floating, additional isolated gate drivers are needed, making the gate driving circuit complicated. In , some non‐isolated high step‐down converters are proposed. The converters use switched inductors and switched capacitors to achieve high step‐down gain.…”