The roof surfaces within urban areas are constantly attracting interest regarding the installation of photovoltaic systems. These systems can improve self-sufficiency of electricity supply, and can help to decrease the emissions of greenhouse gases throughout urban areas. Unfortunately, some roof surfaces are unsuitable for installing photovoltaic systems. This presented work deals with the rating of roofsurfaces within urban areas regarding their solarpotential and suitability for the installation of photovoltaic systems. The solarpotential of a roofćs surface is determined by a new method that combines extracted urban topography from LiDAR data with the pyranometer measurements of global and diffuse solar irradiances. Heuristic annual vegetation shadowing and a multi-resolution shadowing model, complete the proposed method. The significance of different influential factors (e.g. shadowing) was analysed extensively. A comparison between the results obtained by the proposed method and measurements performed on an actual PV power plant showed a correlation agreement of 97.4%.
COBISS.SI-ID: 16262934
The paper shows competences of the project team members in the filed of converter design and control. This paper presents a torque ripple reduction approach to the direct torque control of a permanent magnet synchronous motor, using a sliding mode control technique. A distinctive feature of this approach is that, by appropriately parameterizing and implementing the sliding mode controller, the discontinuous nature of the voltage source inverter may be directly incorporated into the design process. The key idea is to incorporate the benefits of the variable structure systems control design and the event-driven sequential control structures in order to raise the system’s performance and control efficiency. A predictive sliding mode controller has been developed, designed as finite-state automata, and implemented using a field-programmable gate array (FPGA). This new FPGA logic regarding torque and speed control has been developed, analyzed, and experimentally verified.
COBISS.SI-ID: 16609046
An already published current control strategy for the coupled-inductor buck–boost converter is able to change its aim from controlling the input current to controlling the output current, and vice versa, depending on the instantaneous operation point and the applied current references. The main drawback of the two PI-based control implementation is its slow response when the control aim is changed from one current to the other. Due to the magnetic coupling, the converter’s control-to-input and control to-output current small signal transfer functions exhibit similar first-order characteristics. Therefore, it is possible to transform the previous control scheme to a PI-based one that exhibits faster and, in certain cases, much faster transitions between input and output current control operation. The presented experiments also show that the steady-state behavior of the converter is unaffected by the new control implementation.
COBISS.SI-ID: 16608534