Abstract-Single-switch inverters such as the conventional class E inverter are often highly load sensitive, and maintain zero-voltage switching over only a narrow range of load resistances. This paper introduces a design methodology that enables rapid synthesis of class E and related single-switch inverters that maintain ZVS operation over a wide range of resistive loads. We treat the design of Class-E inverters for variable resistance operation and show how the proposed methodology relates to circuit transformations on traditional class E designs. We also illustrate the use of this transformation approach to realize  2 inverters for variable-resistance operation.The proposed methodology is demonstrated and experimentally validated at 27.12 MHz in a class E and  2 inverter designs that operate efficiently over 12:1 load resistance range for an 8:1 and 10:1 variation in output power respectively and a 25 W peak output power.

We determine analytical extended traveling-wave and spatiotemporal solitary solutions to the generalized (3+1)-dimensional Gross-Pitaevskii equation with time-dependent coefficients, for the sinusoidally time-varying diffraction and quadratic potential strength. A number of periodic and localized solutions are obtained whose intensity does not decrease in time in the absence of externally induced gain or loss. Stability analysis of our solitary solutions is carried out, to display their modulational stability.

Analytical solutions to the (3 + 1)-dimensional Gross-Pitaevskii equation in the presence of chirp and for different diffraction and potential functions are found. We utilize a method we formulated to solve the Riccati equation for the chirp function that arises when the F-expansion technique and the homogeneous balance principle are applied to the Gross-Pitaevskii equation. Three specific examples of physical interest are considered in some detail.

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Dynamically-tunable impedance matching is a key feature in numerous radio-frequency (RF) applications at high frequencies (10 s of MHz) and power levels (100s-1000 s of Watts and above). This work develops techniques that enable the design of high power tunable matching networks (TMN) that can be tuned orders of magnitude faster than with conventional tunable impedance matching techniques, while realizing the high power levels required for many industrial applications. This is achieved by leveraging an emerging technique -known as phase-switched impedance modulation (PSIM), which involves switching passive elements at the rf operating frequency -that has previously been demonstrated at rf frequencies at up to a few hundred Watts. In this paper, we develop design approaches that enable it to be practically used at up to many kilowatts of power at frequencies in the 10 s of MHz. A detailed analysis of the factors affecting the losses as well as the tradeoffs of a basic PSIM-based element is provided. Furthermore, it is shown how incorporating additional stages to the PSIM-based element, including impedance scaling and / or the addition of series or shunt passive elements, influences the losses and enables the efficient processing of high power levels given the limitations of available switches. A PSIM-based TMN that matches load impedances to 50 and delivers up to 1.5 kW of power at frequencies centered around 13.56 MHz is implemented and tested over a load impedance range suitable for various industrial plasma processes.