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A new dual T-type 13-level inverter topology is presented in this article, featuring less power switches, gate drivers, and diodes, than inverters based on traditional multilevel topologies, such as neutral point clamped, flying capacitor, T-type and cascaded H-bridge, or previously proposed reduced switch count 13-level inverter topologies. Moreover, no additional circuits are required to equalize the voltage of capacitors present in each pole, nor complex modulation strategies, leading to a reduction of cost and power losses. Exploiting a nearest level modulation technique, the proposed topology performs well in terms of efficiency and total harmonic distortion, as confirmed by experimental tests.

Measuring the gate-source voltages of wide bandgap (WBG) devices in half-bridge converters provides useful information about susceptibility to crosstalk, which can cause uncontrolled cross-conduction and excessive gate-oxide stresses. However, parasitic elements of the printed circuit board (PCB) and device packaging can compromise measurement accuracy, causing unreliable results. Here we describe how this shortcoming can be addressed using devices in packages that have a Kelvin source pin, allowing a more accurate analysis.

The aim of this article is to provide an accurate modeling of the resolution of rotor position measurement and to evaluate its impact on speed estimation required for electric drive control. Starting from the space vector model of a spatially quantized rotor position measurement, the novel concept of instantaneous quantized speed is introduced, which is shown to constitute the effective input to any speed estimation algorithm. Time-harmonic formulations that are valid under periodic torque disturbances are also derived. These expressions, based on modulation theory, justify the presence of otherwise unexplained time harmonics in the measured rotor position and estimated speed, which appears when the shaft is subjected to torque disturbances. Analytical and numerical results are provided on a well-known observer structure to validate the filtering action of speed estimation algorithms on the harmonics of the instantaneous quantized speed. Finally, experimental verification on a 400 W permanent magnet (PM) servo drive is presented.

Power converters and semiconductor devices are spreading their application fields, due to new renewable energy and automotive frameworks. In the electrified vehicles context, the even more stringent requirements, both in terms of performances and reliability, pose new challenges in the design phase of power switches. This paper analyzes, by means of finite-element simulations, a low-voltage power semiconductor system-in-package devoted to automotive applications, which integrates a MOSFET-based half bridge and a controller. Three simulation physical domains integrated in a unique flow are considered: thermo-mechanical, electromagnetic, and thermal numerical models. The aim is to develop a new comprehensive methodology which starts with a thermo-structural simulation of the package, then computes the on-state resistance and parasitic components to assess the electrical behavior of the package. Finally, a simulation check is made to verify if the power device performances are thermally consistent with applicative conditions.

This paper deals with an original control strategy for AC multidrive systems able to mitigate the effects of failures occurring on one or more drives. A key feature of the proposed technique is that fault tolerance capability is achieved by a suitable reconfiguration of the system in order to allow the healthy drives to provide additional paths for the currents of the faulty drives. Moreover, a modified control algorithm able to enforce the vector control in damaged drives has been implemented, by cooperatively managing some or all the drives of the system. Therefore, differently from previous techniques, the fault tolerance capability is achieved by exploiting the healthy drives, rather than activating back-up inverter legs. As a result, no additional high-frequency switching power devices and related drives circuitries are needed. In the following, two different scenarios will be analyzed, highlighting pros and cons of the proposed approach through simulations and experimental results.