Elektrik-Elektronik mühendisligi

—Multilevel inverters such as flying capacitor, diode-clamped, and cascaded H-bridge inverters are very popular particularly in medium and high power applications. This paper focuses on a cascaded H-bridge module using a single direct current (DC) source in order to generate an 11-level output voltage. The noble approach reduces the number of switches and gate drivers, in comparison with a conventional method. The anticipated topology produces more accurate result with an isolation transformer at high switching frequency. Different modulation techniques can be used for the multilevel inverter, but this work features modulation techniques known as selective harmonic elimination (SHE).This modulation approach reduces the number of carriers with reduction in Switching Losses, Total Harmonic Distortion (THD), and thereby increasing Power Quality (PQ). Based on the simulation result obtained, it appears SHE has the ability to eliminate selected harmonics by chopping off the fundamental output component. The performance evaluation of the proposed cascaded multilevel inverter is performed using PSIM simulation package and THD of 0.94% is obtained.

— Low and medium voltage (LV and MV) distribution networks are operated in a radial configuration, but their topology, especially when highly loaded, is usually meshed in order to improve system reliability and quality of the supply. This makes it feasible to configure the network after an outage to restore the service to affected sites. In addition, by modifying the topology of the network, power loss and node voltage deviation can be minimize. However, this network modification is a non-linear, multi-objective, constrained and combinatorial optimization problem. In this paper, Binary Particle Swarm Optimization (B-PSO) technique is employed for optimal network reconfiguration of primary distribution network. The objective of the proposed method is to minimize the total active power loss and voltage deviation experienced in the network. It is carried out subject to varieties of technical constraints, with the search space being the set of networks branches. To ascertain the efficiency of the proposed method and its practicability on multi-scale distribution systems, standard IEEE 16-bus, 33-bus and 69-bus test distribution networks are used. The proposed algorithm is implemented in MATLAB and MATPOWER environments. The results obtained signifies the effectiveness of the proposed technique.

In this paper, a smart grid testbed for electric power
distribution system is presented. The hardware system is
developed and integrated with appropriate software to monitor
various parameters for all connected loads and sources
interconnected through communication networks. The real time
capability of the system would provide operation and analysis
with flexibility and accuracy in all investigations. The system is
designed to emulate real distribution grid, and is intended to
function in laboratory for research and educational setting with
emphasis on analyzing power system component, renewable
energy integration, power quality issues, and consumer load
behavior in smart distribution grid.