BIDIRECTIONAL SOFT SWITCHING SERIES RESONANT CONVERTER WITH PWM CONTROL AND LOAD INDEPENDENT VOLTAGE GAIN CHARACTERISTICS
Mr. Habib Wajid
A fixed frequency operated dual active bridge bidirectional series-resonant (BSR) converter is
proposed for energy storage system in DC micro-grid. Simple PWM control is applied to the
proposed converter to regulate the power flows and achieve the following attractive features like,
the voltage gain of the converter is only determined by the effective duty cycles of switches and
has nothing to do with the amplitude and direction of the transferred power, which is a
significant innovation and improvement in comparison with most of the existing resonant
converters. Theoretically, the normalized voltage gain can be regulated from zero to infinite,
which means the proposed BSR converter is a Buck-Boost converter and suitable for wide
voltage range applications. The direction of power flow and the operation mode, i.e. the forward
or backward mode, can be changed automatically and smoothly with the simple PWM control.
ZVS turn-on is achieved for all the active switches within the entire operation range.