The paper shows the construction and operation of the High-Voltage High-Frequency Coaxial Cable Energy Transfer System dedicated to a three-phase 500 V mining grid with an ungrounded neutral point. The correct operation of the model was verified through simulation and experiments. This paper focuses on the overall system efficiency and the power loss analysis of its components. Based on these measurements, it is concluded that the presented system is suitable for mining applications, where high energy conversion efficiency is essential due to the difficulty of dissipating heat to the environment.

An electronic commutator that can drive a PM BLDC motor either in the full bridge or half bridge configuration has been developed. This commutator allows increasing the motor speed over the nominal value, hence the motor is able to operate within a wide constant power speed range. An application of the commutator with a reconfigurable structure for the double drive of a small electric vehicle Elipsa has been presented. The driveline consists of two independent commutators feeding the motors coupled by gears with rear wheels of the vehicle. Both commutators are controlled by a common control system based on a signal microcontroller. The results of road tests indicate new areas of BLCD motor drives application. The fact that the BLCD motor work in the second speed range does not require any changes in the motor construction and at the same time does not significantly deteriorate the drive efficiency is an indisputable advantage of the presented solution

This paper presents an experimental comparison of the instantaneous power generation of standard and bifacial photovoltaic modules under real operating conditions. The study focuses on short-term effects caused by spatially variable albedo and tracker-induced changes in module orientation. Both modules were installed on the same mobile single-axis tracking platform and had identical rated front-side power, which ensured nearly identical operating conditions and independent MPPT operation. The experimental campaign included five ground surfaces: grass, river sand, grey paver, light aggregate, and dark aggregate. For each surface, electrical parameters and albedo were recorded over the full investigated geometrical range, covering relative solar azimuth from −60° to +60° and module tilt from 0° to 90°. The measured increase in power generation of the bifacial module relative to the standard module depended strongly on the ground surface. Over the full investigated range, the gain was 6.4% for grass, 11.3% for river sand, 5.9% for grey paver, 13.6% for light aggregate, and 4.5% for dark aggregate. These results confirm that, in bifacial photovoltaic systems with tracking, the ground surface and its reflective properties significantly affect the rear-side contribution and instantaneous power output. Consequently, albedo should not be treated as a constant or spatially homogeneous parameter when assessing short-term bifacial PV performance.