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Switching-sequence-based control (SBC) laws when designed based on topological switching behavior can have positive effects on slow- and fast-scale dynamics of a power-electronic system (PES). The slow-scale control can encompass fast PES state regulation and tracking, based on predefined objective, while fast-scale control can address differential-mode (DM) and common-mode (CM) spectral-peak energy associated with PES switching operation. Such control laws may offer enhanced programmability to conventional PES design where bulky electromagnetic interference (EMI) filters have been traditionally used to reduce EMI of switching power converters to meet EMI regulatory standards. An EMI filter is always a less programmable solution since it is usually designed for the worst-case EMI mitigation and usually overkill for a PES operating under reduced load condition. The control scheme outlined in this article offers EMI mitigation across wide operating regions without compromising PES regulation. Moreover, it does so by use of switching sequences that guarantee the reachability of the PES dynamics using an advanced Lyapunov-function-based approach. SBC is a powerful tool to generate control actions for a PES based on multivariate PES state constraints. Hence, contemporary EMI regulatory standards are used as constraints in the SBC formulation to operate the PES under wide operating regime while autonomously mitigating the EMI levels. The work may be of paramount importance for operating the ultra-fast-transition recent wide-bandgap semiconductor devices like GaN–FET and SiC mosfet under higher power with increasing switching frequencies, which is usually desirable for increased power density and reduced switching losses. Here, a hardware Cuk–PES operated with GaN–FETs is fabricated and is used for case illustration. It is shown by experimental results how SBC mitigate DM and CM EMI noise of the PES while maintaining regulation even for the higher order nonminimum phase PES, while reducing sensor requirements using state observer derived from the switching model of the PES.

Increasing the switching frequency of the power semiconductor devices (PSDs) reduces the size and cost of the passive elements, thereby positively affecting the power density of a high-frequency (HF) power electronic system (PES). To achieve a higher switching frequency of a PES, yet low switching losses, the speed of switching transitions of PSDs need to be increased. However, such fast transitions adversely affect PES performance in terms of electromagnetic interference (EMI) and device stress. Hence, a switching transition control (STC) scheme is developed to create optimality between switching PSDs with higher transitions yet maintaining safe levels of parasitic oscillations, that result from reducing the transition time of these devices. The switching transition control (STC) framework helps the HF PES achieve a target efficiency improvement by controlling the high di/dt and dv/dt regions of a PSD on the fly. Results are shown to validate that this improvement of efficiency is not feasible with a passive gate drive. An HF Ćuk PES using a Cree SiC MOSFET half-bridge module is fabricated for the testing purpose of the STC framework. The STC network is based on a simple switched resistor network, synthesized using high-speed GaN-FETs and built across two generations, Gen-1, and Gen-2. Practical operational issues of the STC network with fast switching GaN-FET in the Gen-1 board are analyzed and are overcome with design modification in Gen-2. The work has ramifications in meeting a system-level goal of an HF WBG PES, like a target efficiency increment, while not deteriorating the EMI performance and PSD stress levels that result due to parasitic oscillations in such PES.

A switched resistor based active drive scheme is delineated in this paper. The active gate drive does switching transition control (STC) of a wide bandgap (WBG) SiC MOSFET. Contrary to prevalent active gate drive schemes which are validated on a double pulse (DP) testbed, this paper synthesizes an STC scheme for a WBG PES prototype to meet a system-level goal like efficiency increment. An HF Cuk PES operating at 50 kHz using Cree SiC MOSFET half-bridge module is fabricated for testing purpose of the STC framework. The switched resistor based STC uses HF GaN-FET based network, consisting of state-of-the-art EPC8004 GaN and LMG1020 Texas drivers. The design achieved transitions of 1 ns to create short pulse widths that can control the turn-on trajectory of the SiC device. The simple approach is realized only with the use of an industrial-scale F28379D processor.

This paper delineates a mechanism to attain decentralized control of a high-frequency distributed power system (HFDPS) based on local observation and/or estimation at the source and load ends. An acceptable dynamic performance of the independent control eliminates/reduces the need for high-speed communication (that typically needs to be high because of HF power transfer) between the source- and load-end controllers. This provides practically complete autonomy for the HFDPS. To verify the dynamic performance of the control scheme, start-up, transient and steady-state results have been provided.

Differential-mode Cuk inverter (DMCI) represents a class of single-stage inverter with low device count, modular symmetry, and topological simplicity. Recently, discontinuous modulation scheme (DMS) has been proposed for the DMCI. This paper extends the modular nature of the power stage to the control architecture and proposes a transformation-based tracking controller using adaptive control algorithm for the same. A key challenge in designing a controller for DMS-based DMCI is to take into account the inherent converter nonlinearity and startup transient at the start of every line cycle. Experimental results are provided for startup, steady state, load transition, and total harmonic distortion (THD) using GaN-FET based DMCI, which validate the efficacy of the implemented modular transformation-based tracking controller.

Power electronic systems are gaining widespread importance in contemporary world due to the extensive integration of renewable energy resources into grid. As a consequence of grid integration of renewable energy sources, developing robust control methods for inverters have gained paramount importance, since the control scheme that we apply plays an important role in ensuring stability and good performance of the inverters. Taking this into account, we have designed an optimal switching sequence based controller (OSBC) which ensures stability and robustness of a differential-mode inverter (DMI), which is based on Cuk topology. The controller, so designed, responded well to large signal perturbations under varying operating conditions. The control scheme developed provides good steady state and transient response. The control leads to the rapid convergence of the input inductor current to its reference resulting in fast convergence of the output voltage to its reference ass well.