Wide-bandgap (WBG) semiconductor devices are making their way into large-volume applications, including pivotal domains of societal infrastructure such as sustainable energy generation and conversion. Presented for a long time mainly as a synonym of high-temperature electronics, hands-on experience has highlighted a number of gains that can be drawn from this technology even when used as a straightforward drop-in substitute of silicon in established applications and field-proven designs. Incremental in nature, these gains enable interesting progress beyond state-of-the-art forms, which, though not corresponding to the full exploitation of the potential of this technology, are oftentimes sufficient to justify its adoption. With particular reference to renewable energy power conversion and solid-state transformation, in the context of transport applications and incorporating a storage device, this paper reports on the understanding generated over the past few years and points out some specifically tailored technology and circuit design requirements to ensure overall beneficial impact of the adoption of WBG technology.

The stability problem induced by constant power loads (CPLs) is becoming more prominent in more electric aircraft. In this article, the stabilization issue of dc distribution bus with dual-active-bridge (DAB) converters was investigated. On the basis of voltage regulation, an active damping solution based on model predictive control (MPC) was proposed by explicitly incorporating a stabilization term into a cost function. In this solution, to ensure the output voltage performance with a smaller steady-state error and a dynamic voltage overshoot, an adaptive weighting factor was adopted with a stray resistor taken into account. A theoretical design of the weighting factors was performed using the artificial neural network (ANN) method. The proposed approach could supply stiff load voltage and provide good dc-link voltage stabilization, as well as load voltage overshoot clamping. These findings were verified through the computer simulations and practical experiments of an 800-W converter prototype with a switching frequency of 20 kHz, an input voltage of 270 V, and an output voltage of 270 V.

Solid-state power controllers (SSPCs) have been received increasing attention as they can configure the electrical system and protect the system by fast tripping mechanism at the same time. Although the high-voltage direct current (HVDC) electrical system can bring sustainable savings on the cables' weight and losses, the protection can be considerably challenging. SSPCs have been successfully utilized for 28V DC aircraft onboard network. However, high-voltage ones are impeded by the vast over-voltage and the excessive losses generated from SSPC switching. This paper tries to fill this gap and presents the development of high-power SSPCs for a ±270VDC network of a future turboprop aircraft. Comprehensive designs of proper over-voltage suppression along with SSPC thermal management are presented in this paper. Besides, a comparative study on the SSPC device is carried out. Two prototypes, including a single MOSFET module and paralleling several discrete MOSFET devices, are built and then tested in the experiment. It has been validated that the proposed voltage clamping design cannot only effectively suppress the over-voltage, but also limit the SSPC temperature increase during switching for both candidates. After comparing the conduction losses, maximum junction temperature, power density, weight and volume, the single device solution is recommended as a preferable SSPC option for future aircraft.

In the high-power settings of engine, such as maximum take-off, more power should be extracted from the high-pressure spool of engine (HPS) than the low-pressure spool of engine (LPS) to avoid the overspeed and potential instability of the HPS. However, as revealed in this article, extracting more power from the HPS will degrade the onboard high-voltage direct current (HVdc) grid stability for the conventional single dc bus power generation center. To address this conflict, in this article, an advanced power generation center (APGC) incorporating an extra back-to-back (BTB) converter is introduced to improve the stability for both engine and HVdc grid. The BTB converter connects the HP power generation channel and the LP channel, providing an additional power flow path between the HP channel and LP channel. A transfer function-based impedance model and a state-space model of the HVdc grid are proposed to study the HVdc grid stability. The analytical findings of the HVdc grid stability and stability improvement using the APGC architecture have been verified through simulation and experimental results.