Research And Implementation Of Boost Converter For Energy Harvesting Application

In recent years,as energy harvesting has been widely used in emerging technologies such as smart grid,biomedicine and smart home,boost converters have also been developed rapidly.As a bridge between the energy source and the electric appliances,boost converters need to deal with some design challenges,such as low startup voltage,high conversion efficiency,controllable output voltage,and low implementation cost.In this thesis,a DC-DC boost converter and an AC-DC boost converter are designed and implemented for two kinds of energy sources with different types of output voltages,DC and AC.Compared with the existing research results,the main innovations in this thesis are shown as follows: first,both boost converters adopt cold-start technology,which can work at low input voltage without additional special devices.Second,The DC-DC boost converter circuit adopts a stepping-up architecture with only one off-chip inductor.A zero current switching(ZCS)circuit and a maximun power point tracking(MPPT)circuit are utilized to improve the overall efficiency.Third,the AC-DC boost converter proposes modified active diodes to reduce power losses.In addition,controllable output voltage is implemented by pulse width modulation(PWM).The two boost converters in this thesis were designed in 0.18?m CMOS process.The boost DC-DC converter has been completed with chip fabricating and testing.Measured results show that chip has a peak energy conversion efficiency of 60%,an output voltage of 1.2V ~ 1.6V,a minimum start-up voltage of 190 mV and a minimum operating voltage of 50 mV.For the AC-DC boost converter,the schematic has been completed with simulation results.A peak efficiency of 52.5% is obtained.The output voltage of the converter is 1.2V and the minimum startup voltage is 800mV(AC amplitude).Among them,the DC-DC boost converter can be utilized in energy harvesting with thermoelectric generator(TEG),and the AC-DC boost converter can be applied in the collection of alternating electromagnetic energy.