The paper deals with the new method of analysis, synthesis and experimentation of single-phase power active filters. Using a new particular transformation theory the ordinary single-phase system can be transformed into equivalent two-axes orthogonal one. The new original thought is based on the idea that ordinary single-phase quantity can be complemented by fictitious second phase, so that both of them will create orthogonal system, as is usual in three-phase systems. Application of above theory makes possible to use complex methods of analysis as instantaneous reactive power method, which have not been usable for single-phase systems so far. Both, the active and reactive powers can be determined by this way. Practical application of the method is outlined for the case of reference current determination for single-phase power active filter. The paper shows some examples of the simulation verification results, which proved a high accuracy and extremely fast response of the single-phase active filter with control, based on the introduced method. The effectiveness of proposed control algorithm is also demonstrated by experimental results, which were carried out on the single-phase active parallel filter.

The expected increase in electric vehicles necessitates an expansion in charging stations. However, this increase could introduce issues to the power grid, such as the deterioration of voltage stability and an increase in microgrid loading. To address these issues, innovative solutions are imperative. One potential solution is the implementation of charging control mechanisms. This paper analyzes the impact of a residential charging station on a low voltage microgrid from the power quality point of view using a one-year operation simulation. Thirty-seven charging station scenarios with different locations within the network were examined, including instances with no charging control and various combinations involving charging control, photovoltaic power plant, and battery energy storage system. The simulation results of the charging station without charging control show a decrease in some power quality indicators, such as exceeding voltage change thresholds after charging station connection and increasing power losses. On the contrary, the scenarios implementing charging control and local resources effectively mitigate the adverse effects of charging stations on the microgrid.

The paper deals with designing and implementation of Smart Grid model with designing of power quality measurement software in these networks. There was created a simulation model which has the same parameters setting as the real network. Various renewable energy sources represented by small hydropower plant, photovoltaic power plant and wind power plant are integrated in the designed scheme of Smart Grid. A part of the real network model in laboratory environment is controlling and evaluating SCADA system which was designed in LabVIEW programme. This system provides real-time control of power switching relays, obtains information about their status and performs three-phase measurement. The basic system displays information about voltage, current, and total harmonic distortion. SCADA system can perform detailed power quality measurement in individual points. The system supplies three types of customers, namely industrial zone, a city and two villages. The entire system is connected into a mash-grid structure. Several analyses and measurements were carried out for the given structure in order to obtain results for optimal operation of the network focusing on the power quality in Smart Grid.

This paper deals with a method for the optimal settings of distributed sources in order to reduce power losses and to keep bus voltages within permissible range in the distribution network. The optimal reactive dispatch of generators may be considered as a complex optimization problem. In this paper a Particle Swarm Optimization algorithm (PSO) as a suitable tool is used.