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The Z-source inverter (ZSI) employs an LC impedance network between the main inverter bridge and the power source. The unique feature of the ZSI is that it can operate either in buck or boost mode with a wide range of obtainable output voltages from a given input voltage. This topology also exhibits better electromagnetic-interference noise immunity when compared to a traditional voltage-source inverter (VSI). However, the LC impedance network of ZSI significantly increases the size and cost of the power converter and can make it unsuitable for low-power applications. This paper proposes a novel topology called switched boost inverter (SBI) which exhibits similar advantages of ZSI with lower number of passive components and more active components compared to ZSI. The steady-state and small-signal analyses of SBI, along with its pulsewidth modulation (PWM) control strategies, have been discussed in this paper. This paper also presents a comparison of SBI and ZSI with the same input and output parameters. The theoretical analysis given in this paper has been validated using a laboratory prototype of SBI, and the experimental results are presented for verification. The experimental harmonic spectrum of the inverter's output voltage with the proposed PWM technique is also plotted and compared with that of a traditional VSI. All the experimental results show good correlation between theory and experiments. [ABSTRACT FROM PUBLISHER]

Abstract-Hysteretic modulators have superior dynamic performance, and they also help reduce the number of output capacitors without sacrificing the transient response. For proper hysteretic operation, the voltage ripple is required to be piecewise linear and noise free. With modern computational integrated circuits lower supply voltage with tight regulation requirements, the output voltage ripple is both small and noisy. The synthetic ripple modulator (SRM) allows proper hysteretic operation even with a small and corrupted output voltage ripple. This paper discusses the dynamic behavior of the SRM. Small-signal characteristics of the modulator are derived. An easy-to-use numerically efficient model has been developed to accurately predict the smalland large-signal behavior of the converter driven by the SRM. The model is able to predict the small-signal behavior of the SRM up to half the switching frequency with sufficient accuracy. It can predict the same large-signal responses as real-time simulation, but at two orders of magnitude less in computation time. Laboratory tests on a 1.8 V/20 A single-phase prototype shows good correlation between experimental results and theoretical predictions both in frequency and time domain. [ABSTRACT FROM AUTHOR]