Regenerative‐passive snubber two‐switch forward converter

Abstract

A regenerative-passive snubber (RPS) for pulse-width modulation (PWM) two-switch forward converter (TSFC) is presented. The RPS circuit is recycled the magnetic energy stored in the transformer leakage inductor and is achieved zero voltage switching turn off of power switches. Moreover, the RPS provides the resonant path formed by snubber capacitors and the snubber inductor to achieve zero current switching (ZCS) turn on of switches. In addition, the output diodes turn on/off under ZCS. The proposed RPS-PWM TSFC is analysed and experimental result for a 160 W, 300 kH prototype at the output voltage of 32 V are obtained to verify the theoretical analysis.

Bidirectional isolated three‐phase dc‐dc converter using coupled inductor for dc microgrid applications

“…It can be seen that in operation at the duty cycle range 1/3 ≤ D < 2/3, the maximum current ripple value of the proposed topology is 0.0083 occurs at D = 1/2, where this value is one‐third compared with Jin and Liu 23 and half value compared with Bal et al 51 While in operation at duty cycle range 2/3 ≤ D < 1, the current ripple of studied topology is higher than that of the converter in Bal et al 52 ; when the duty cycle is equal to 5/6, and the normalized current ripple is equal to 0.0083. Furthermore, the current ripple of the previously proposed converters in previous studies 26 , 51 is higher than that of the proposed topology, according to the values shown in Figure 12A. Also, the normalized current ripple cancellation of the proposed topology occurs when the duty cycle is 1/3 and 2/3, which means that the proposed topology has a better dynamic response and smaller size inductor.…”

“…The dc voltage gain of NTBDCs is significantly limited; however, the dc voltage gain of ITBDCs is achieved by adjusting the transformer turns ratio; however, using high voltage transformers with a large number of turns also can introduce several problems, for instance, the leakage inductance and the parasitic capacitance of the transformer may cause voltage and current spikes, increased losses, and noises that degrade the converter performance. To overcome the previous disadvantages of the converters based on the transformer, the clamp circuit techniques are introduced to recycle the energy stored in the leakage inductance and absorb the voltage spikes on the main switch 38–45 . Although of drawback, the galvanic isolation has the following advantages: These are necessary for many industrial applications; the electrical grounds of the two electrical systems may be at different potentials; personnel safety; increases the filter's operation frequency; noise reduction; and correct operation of protection systems are the main reasons behind galvanic isolation.…”

“…To overcome the previous disadvantages of the converters based on the transformer, the clamp circuit techniques are introduced to recycle the energy stored in the leakage inductance and absorb the voltage spikes on the main switch. [38][39][40][41][42][43][44][45] Although of drawback, the galvanic isolation has the following advantages: These are necessary for many industrial applications; the electrical grounds of the two electrical systems may be at different potentials; personnel safety; increases the filter's operation frequency; noise reduction; and correct operation of protection systems are the main reasons behind galvanic isolation.…”

Forward converter using a resonant auxiliary circuit to provide soft‐switching and reset the magnetic core

“…Moreover, in the proposed converter, no isolated gate driver is needed unlike the converters in refs. [8], [15,16], [19], [23,24], and [27] which have floating switches, resulting in a more complex gate driver and higher cost. In ZCZVT converters in refs.…”

“…However, LPS circuits can only provide zero current switching (ZCS) condition for the switch at turn-ON and zero voltage switching (ZVS) condition for the switch at turn-OFF. ZCS turn ON leads to capacitive turn-ON loss which degrades the converter efficiency at high frequencies [14][15][16]. Besides, LPS circuits usually require many passive components, which lead to high circulating current and conduction loss.…”