A New High Efficiency Tri-State Boost Converter

Conventional two-state dc to dc voltage converters have in their small signal transfer function a right half planzero in pole-zero plane whichthis zero result in speed reduction and lowfrequency operation, especially, because position of the zero is not fixed andmovesby the load variation. To remedy this problem the tri-state boost converters have been introduced. These converters haven’t the mentioned right half planzero,hence have higher speed and stability,but, they have lower efficiency because of the existence of afreewheeling mode in their operation.In this paper we have modified the conventional topology of tristate boost converters by replacing the diode in the free mode with a MOSFET transistor. Both simulation results and experimental results are introduced in the paper and they show a 9% improvement in the efficiencyof tri-state boost converter using the proposed modification. KeywordsTwo-state boost converter, Tri-state boost converter, right half plan zero, efficiency, transient response.