The power quality problems can be defined as the difference between the quality of power supplied and the quality of power required. Recently a large interest has been focused on a power quality domain due to: disturbances caused by non-linear loads and Increase in number of electronic devices. Power quality measures the fitness of the electric power transmitted from generation to industrial, domestic and commercial consumers. At least 50% of power quality problems are of voltage quality type. Voltage sag is the serious power quality issues for the electric power industry and leads to the damage of sensitive equipments like, computers, programmable logic controller (PLC), adjustable speed drives (ADS). The prime goal of this paper is to investigate the performance of the Fuzzy Logic controller based DVR in reduction the power disturbances to restore the load voltage to the nominal value and reduce the THD to a permissible value which is 5% for the system less than 69Kv. The modeling and simulation of a power distribution system have been achieved using MATLABL/Simulink. Different faults conditions and power disturbances with linear and non-linear loads are created with the proposed system, which are initiated at a duration of 0.8 sec and kept till 0.95 sec.

The Dynamic Voltage Restorer (DVR) is one of the most efficient and effective custom power devices in protecting the sensitive equipment against voltage sag and voltage harmonics due to; lower cost, smaller size and dynamic response. The inverter is the core of the DVR and it directly affects the performance of the DVR, incorrect injection or delay in the process would be dangerous to sensitive loads. The major functions of the DVR controller are, detection of voltage disturbances events in the system, calculation of the compensating voltage and generation the reference signal for the PWM to trigger the voltage source inverter. PI controller and fuzzy logic controller has been compared with the proposed fuzzy neural optimized fuzzy logic controller in correcting the sag problems and mitigating the harmonics distortion with linear and nonlinear loads. Fuzzy Neural optimized Fuzzy Logic controller is the most efficient in improving the performance of the Dynamic Voltage Restorer in compensating any kind of voltage variations and reducing the voltage Total Harmonic Distortion (THD) by enhancing an injection capability of the DVR which is highly influenced by a control algorithm employed. The system is simulated in MATLAB and results confirm the validity and feasibility.

The highest power production for solar panels in the months between April and October, as the days are longer and there is more sun than any other months. On the other hand, the electricity demand is highest in the summer months, since households and businesses are using air conditioning on hot days. on-grid solar systems could be one of the solutions to the issue of increasing demand for electrical energy in the hot day, also these systems do not require bulky and costly batteries and need fewer solar panels due to no need for generating extra power when there is no sunlight, these advantages made this method the most common solar systems and widely used for homes and business. This article highlights the methods of solar systems connecting, and presents the sizing of the (on-grid) solar system with a capacity of 10kw.

Abstract— Recently a large interest has been focused on power quality field due to: disturbances caused by non-linear loads, Increase in the number of electronic devices and renewable energy sources. Power quality measures the fitness of the electric power transmitted from generation to the industrial, domestic and commercial consumers. In a power system voltage distortion introduced by harmonics and voltage sags are the most severe affecting power quality, because of both consumers and utilities are affected by these disturbances. Different methods to enhance the power quality but the custom power device is the most effective and efficient method. One of which is the use of Dynamic Voltage Restorer (DVR). The performance of the DVR based on Fuzzy Neural controller to restore the load voltage to its nominal value under different fault conditions and power disturbances is presented in this paper. Simulation results are carried out using MATLAB/SIMULINK program. The faults and disturbances are initiated at 0.8s and kept till 0.95s.

The exhaustion of conventional resources and its effect on climate requires an urgent need for the substitute power resources to attain energy demand. Solar energy is an infinite, a futuristic, non-polluting, diverse applications, Low installation and maintenance cost. This paper presents the complete design of a 10kw, stand –alone rooftop solar system, and describes the impact of an effective implementation of a power system and a control system on the performance of the project. The power system in this project consists of an array of half cut cell PV modules, and an inverter based on Mn-Zn ferrite transformer to boost the D.C voltage generated by the PV modules. Control system includes voltage regulator based on PI controller and SPWM generator. Voltage regulator generates three modulating signals used by SPWM to generate pulses to switch 6 IGBT inverter at a certain switching angles. The proposed system is implemented in the MATLAM/simulink. Simulation results indicate that an effective implementation of the power system and the control system will provide a high quality rated voltage with minimal limits of the Total Harmonics Distortion (THD) and acceptable values of the modulation index (m) over a wide range of increasing in temperatures.