The PICOSEC Micromegas (MM) detector is a precise timing gaseous detector based on a MM detector operating in a two-stage amplification mode and a Cherenkov radiator. Prototypes equipped with cesium iodide (CsI) photocathodes have shown promising time resolutions as precise as 24 picoseconds (ps) for Minimum Ionizing Particles. However, due to the high hygroscopicity and susceptibility to ion bombardment of the CsI photocathodes, alternative photocathode materials are needed to improve the robustness of PICOSEC MM. Diamond-like Carbon (DLC) film have been introduced as a novel robust photocathode material, which have shown promising results. A batch of DLC photocathodes with different thicknesses were produced and evaluated using ultraviolet light. The quantum efficiency measurements indicate that the optimized thickness of the DLC photocathode is approximately 3 nm. Furthermore, DLC photocathodes show good resistance to ion bombardment in aging test compared to the CsI photocathode. Finally, a PICOSEC MM prototype equipped with DLC photocathodes was tested in muon beams. A time resolution of around 42 ps with a detection efficiency of 97% for 150 GeV/c muons were obtained. These results indicate the great potential of DLC as a photocathode for the PICOSEC MM detector.

PICOSEC Micromegas (MM) is a precise timing gaseous detector based on a Cherenkov radiator coupled with a semi-transparent photocathode and an MM amplifying structure. The detector concept was successfully demonstrated through a single-channel prototype, achieving sub-25 ps time resolution with Minimum Ionizing Particles (MIPs). A series of studies followed, aimed at developing robust, large-area, and scalable detectors with high time resolution, complemented by specialized fast-response readout electronics. This work presents recent advancements towards large-area resistive PICOSEC MM, including 10 × 10 cm² area prototypes and a 20 × 20 cm² prototype, which features the jointing of four photocathodes. The time resolution of these detector prototypes was tested during the test beam, achieved a timing performance of around 25 ps for individual pads in MIPs. Meanwhile, customized electronics have been developed dedicated to the high-precision time measurement of the large-area PICOSEC MM. The performance of the entire system was evaluated during the test beam, demonstrating its capability for large-area integration. These advancements highlight the potential of PICOSEC MM to meet the stringent requirements of future particle physics experiments.

This paper presents an experience in the design and implementation of the condition-monitoring system for the synchronous generators whose primary purpose is to record data for the identification of the capability limits of the P–Q diagram of three generators in hydro power-plant. Paper presents details about the monitoring system, the underlying theory of the identification of the synchronous generator model with a focus on the calculation of the capability limits in the P–Q diagram. Furthermore, a computationally efficient method for the representation of capability limits suitable for the implementation within the industrial automation and control system of the power-plant is described in detail. Finally, the capability diagrams for three generators were implemented in the power-plant supervisory control and data acquisition system (SCADA) system.

Recent advances in the control of grid-side converters (GSCs) aim to improve system reliability by eliminating the need for voltage sensors. Effective control without voltage sensors requires both synchronization before the GSC is connected to the grid and continuous operation afterwards. To meet these two requirements, a novel voltage sensorless control method is proposed using a robust and reliable estimation structure with a sliding-mode observer (SMO) and a double generalized second-order integrator with frequency-locked loop (DSOGI-FLL). The main objective of sensorless start-up of GSC is to suppress the inrush current that occurs when the grid and GSC voltages are not well synchronized. To achieve this, the discontinuous operation of the GSC is exploited by forcing controlled short circuits at the GSC terminals, resulting in a discontinuous current between the grid and the GSC. Therefore, the proposed estimation structure is analyzed and adapted to operate properly in discontinuous operation. Thus, a successful synchronization, i.e. an estimation of the grid angle and amplitude, is ensured based on the sampled counterpart of the discontinuous current. After synchronization and with only minor modifications to the estimation structure, the proposed method also enables stable operation in continuous mode, which implies standard voltage-oriented control (VOC) with pulse-width modulation (PWM). Consequently, the whole process of voltage sensorless control of the GSC is performed using a single estimation structure, which is inherently robust to disturbances such as voltage distortion due to the specific characteristics of SMO and DSOGI-FLL. The proposed method is validated by simulations and experimental tests.