In the last years, low pressure ozone UVC mercury germicidal lamps have been widely used to decontaminate air, surfaces, and water. This technology is mature, and it has been widely used during the pandemic as a measure against SARS-COV-2, the coronavirus that causes COVID-19; because the exposure of this virus to the wavelength wave of 254 nm has been proven to be an effective way to eliminate it. However, the Minamata Convention in 2013 decided to limit mercury lamps by 2020; therefore, the development of new technology devices based on UVC-LEDs (short-wave ultraviolet, light-emitting diodes) are receiving a lot of attention. Today, this technology is commercially available from 265 to 300 nm peak wavelengths, and recently up to 254 nm. Notwithstanding, due to the characteristics of these LEDs, arrangements with a precisely dosed power supply are regularly required to provide effective decontamination. Thus, this paper reports the design and implementation of a power electronic converter for an array of 254 nm UVC-LEDs, which can be used to decontaminate from SARS-COV-2 in a safe way.

Six-phase drives are gaining popularity in electric vehicle (EV) applications owing to their superior fault-tolerance capability, modularity, and improved current handling. However, a thorough design of a six-phase traction inverter has not been investigated. As a result, inherent advantages of six-phase inverters are not exploited. This paper presents a holistic design methodology for a six-phase traction inverter. At the power device level, discrete Silicon Carbide (SiC) MOSFETs are utilized, and their electrothermal model is used to effectively size a liquid-cooled heat sink. At the DC-capacitor level, a multi-objective optimization algorithm is proposed to find the most suitable capacitor bank in terms of volume, impedance, and current capability. At the system level, coreless hall-effect current sensor integrated circuits (ICs) are proposed to mitigate the higher count of sensors in six-phase systems. At the mechanical design level, design constraints are considered to deliver a housing with an integrated coolant channel. The resultant inverter design is prototyped and experimentally tested. The proposed design demonstrates a 7% reduction in DC-capacitor volume and 21% reduction in cabling cost when compared to conventional three-phase inverters of the same volt-ampere rating. The peak power density of the prototype inverter is 70 kW/L, demonstrating a compact design.

Today, switched reluctance motors (SRMs) represent a promising technology for the long-term sustainability of electrified transportation, mainly due to their simpler structure, lower production cost, and robust configuration compared to other motor technologies. Notwithstanding, high acoustic noise and torque ripple are two performance imperfections that have prevented the widespread implementation of SRMs. This paper presents different structural design techniques to reduce the acoustic noise of an 8/6 SRM, while maintaining the electromagnetic performance of the machine. For each technique, a corresponding multiphysics FEA analysis of the motor’s performance is presented. The accuracy of the multiphysics model is confirmed experimentally using acoustic noise measurements obtained from a four-phase 8/6 SRM. Then, several structural techniques have been investigated on the 8/6 SRM represented in two main categories: stator-housing modifications and rotor modifications. The best design strategies are then combined to improve the acoustic noise level of the 8/6 SRM while maintaining its performance.

There is an increasing research focus on computationally evaluating the acoustic noise and vibration of Switched Reluctance Motors (SRMs) using Finite Element (FE) tools. The accuracy of the calculated acoustic behavior of an electric motor relies heavily on the fidelity of the finite element model. The finite element model of a stator-housing assembly poses a challenge due to the orthotropic behavior of electrical steel and the non-uniform geometry of the windings. This paper introduces an experimental modal analysis approach to calculate the modal characteristics of a 12/8 SRM stator-housing assembly, investigating the effects of winding and housing on these characteristics. Additionally, the study involves analytical calculation and finite element modeling, correlating the results with experimental values to enhance understanding and accuracy in predicting acoustic behavior. It also presents a polynomial function to calculate modal damping parameters and investigates the applicability of the analytical equations commonly used in the literature to the tested SRM.

Switched reluctance motors (SRMs), known for their simple construction, high efficiency, and robustness, are increasingly being adopted across various applications. In an industrial setting, these motors offer a promising alternative to traditional induction motors (IMs), particularly due to their lower sensitivity to temperature and ability to perform reliably in harsh environments. While commercially available variable frequency drives (VFDs) are readily accessible for IMs, the same is not true for SRMs, limiting their broader adoption in the industry. This paper presents the design and implementation of a high-efficiency, integrated, bidirectional drive for an SRM for industrial applications. An analysis of the current SRM market, along with a review of related research, has been conducted. Based on this analysis, existing gaps in SRM drive solutions have been identified, and the design requirements for the proposed drive have been defined. Subsequently, a 10 kW silicon-carbide (SiC)-based converter topology is designed, developed, and experimentally validated. The proposed converter achieves a peak efficiency of 97.03% at the power factor correction (PFC) stage and 98.90% at the motor drive stage under nominal power conditions.

This paper introduces a new DC solid-state circuit breaker (SSCB) concept using a small inductor, which is similar to the inductor used in electro-mechanical breakers. The new SSCB scheme uses the voltage inductor to activate a short circuit protection, in this way the circuit starts to open in the moment of fault condition to prevent the over load current.