This paper presents an efficient algorithm for optimization of radial distribution systems by a feeder reconfiguration to balance feeder loads and eliminate overload conditions. The system load-balancing index is used to determine the loading conditions of the system and maximum system loading capacity. The index value has to be minimum in the optimal feeder reconfiguration of load balancing. A method based on Tabu search algorithm The Tabu search algorithm is employed to search for the optimal feeder reconfiguration. Simulation results for a radial 69-bus system with reconfiguration and capacitors placement. The study results show that the distribution system with capacitor placement and optimal on/off patterns of the switches feeders reconfiguration can be load balancing in distribution systems.

To store electrical power from solar cells are generally used battery as storage. Recent development in capacitor technology achieves with higher capacitancc smaller and low cost especially dcvelopment of a supcr capacitor (doublc laycrs). This research study used a super capacitor to store electrical power from solar cells. The results show that super and electrolyte capacitor can be used without battery with more power density and fast charge. But capacitor discharging must be controlled. The important disadvantage is super capacitor is used with low voltage and high rate of charge leakage. In case of electrolytic capacitor can use with higher voltage low rate of charge leakage but lower capacitance.

This thesis presents the Power Quality (PQ) analysis of solar power plant 1MW and economic impacts in the distribution power networks. The case study focuses on the penalty fee (fine) from consume the reactive power less than the limit of the Provincial Electricity Authority (PEA) of Thailand. The fine have been charged up to 900000 baht per year. Therefore the thesis studies and purposes the possible solution by analysing the operating function of the inverter (supports reactive mode) installing the adjustable capacitor bank 1500kVar in the Medium Voltage (MV) level and lastly installing the adjustable capacitor bank 1500kVar in the Low Voltage (LV) level. The results shown that the possible solution that reduces the fine is installed the adjustable capacitor bank 1500kVar in the MV. The investment of this installation is cost 1800000 baht with the nominal operation over 10 years. The analysis of financial investment which bases on the Net Present Value (NPV) the Benefit-Cost ratio (B/C) the Pay Back period (PB) is presented the NPV at 4902971 baht B/C 3.72 and PB 2 year (with the Internal Rate of Return; IRR 49.7 percent).