There is a lack of knowledge on the development of a controller model into a black box dynamically-linked library (DLL) file which can be flexibly tested with a power system model through a real-time co-simulation platform. Developing a test bed to demonstrate the performance and compliance analysis enhances the approval of novel control and protection strategies. This paper presents the development of a controller DLL and a test bench that integrates this DLL with a real-time simulator. The DLL contains a previously developed grid-forming controller for the type‑3 wind turbine and works in co-simulation with the power system model on Real-Time Digital Simulator (RTDS) in real-time.

Unlike synchronous generators, the fault response of grid-forming (GFM) inverter-interfaced distributed generators (IIDGs) is notably governed by the selection of control and current limiting strategies rather than inherent physical traits. While recent research has focused on the sequence domain fault model of GFM IIDGs, a research gap exists in elucidating the influence of control and current limiting schemes on this model's characteristics. This article aims to fill this void by examining how different control and current limiting schemes influence the positive and negative sequence impedances in the phasor-domain fault model of GFM IIDGs. This investigation encompasses droop-based, virtual synchronous machine-based, and virtual oscillator-based reference generation controls alongside rotating and stationary reference-frame-based voltage controls. Furthermore, saturation-based, latching-based, circular and virtual impedance-based current limiting schemes are analyzed. To achieve this goal, a thorough numerical simulation study is conducted. Findings indicate that outer reference generation controls exhibit minimal impact. Conversely, the choice of voltage control and various current limiting schemes emerge as the predominant factors shaping the sequence models of GFM IIDGs. These analyses and results are instrumental in devising reliable protection strategies within inverter-based grids, as a comprehensive understanding of electrical elements in the sequence domain is imperative for effective protective measures.

Taking a nap is a welcome pastime in vehicles such as trains, airplanes, and cars. Flat sleeping cannot always be facilitated because of space and economic constraints, but a larger backrest recline angle is associated with better sleep quality. To define the best and the worst comfort experience and sleep comfort in these settings, and to offer design guidelines to practitioners, six backrest recline angles were compared regarding overall comfort and sleep comfort. The backrest recline angles ranged from 110 to 150 degrees, and 180 degrees was added as a reference. 16 participants were invited to sleep for a duration of 90 min. in each condition. Overall comfort and sleep comfort significantly improve in conditions higher than 120 degrees. Local discomfort is rated relatively low in all angles, but in comparison, people experience high discomfort in the neck, lower back, and lower leg region while in the 110 and 120 degrees condition. It is concluded that in the bigger recline angles the napping comfort experience is higher, with a minimum advised angle of 130 degrees.

The sleep quality and (dis)comfort sitting upright was studied among 40 participants who took a nap at home. They were asked to take a nap at 17:00h on three consecutive days. The backrest had to be at a different angle every day: upright, reclined and more reclined. They were asked to record the backrest angle of the three positions and report the length of the sleep, the sleep quality, comfort and discomfort and influence of other factors each during each nap. From the 120 cases (3 conditions, 40 participants), the cases where participants were not able to sleep had an average backrest angle of 110˚, which was significantly different from the cases where participants were able to sleep, who had an average backrest angle of 118˚. The scores in the more upright position (<110˚) resulted in significantly more discomfort and a lower sleep quality than in the reclined positions (>123˚). As the conditions were arranged by the participants, there was much variation in outcomes. Therefore, future research under more standardised conditions is recommended.