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Electric power systems are experiencing a growing number of electronic loads in the residential sector as modern appliance technology progresses, and it has become increasingly more important to consider the total power factor (PF) of residential communities. This paper provides a survey based on literature and publicly available information of typical appliance PF values and effects at the residential level as well as a discussion on appliance energy use and corresponding operation schedules. A procedure for the calculation of equivalent PF is proposed and exemplified with minutely experimental data at 15-minute and hourly time intervals, which correspond to smart metering and traditional practices, respectively. The application of the proposed equivalent PF procedure in coordination with building energy modeling, may, in principle, be employed to determine PF for entire communities at an aggregated level. The paper includes a proposal to simulate reactive power through an approach that utilizes EnergyPlus, a building energy modeling software. Such simulation capability could facilitate improved planning for compensation implementation both in electric power distribution networks and in individual residences, which offers significant opportunity for energy savings.

In the future, active network management (ANM) and adaptive distributed energy resources (DER) control schemes will be increasingly required to fulfill growing power system resiliency and renewable generation integration needs. As part of future ANM schemes more frequent electricity distribution network topology changes could be utilized to improve the electricity supply reliability. However, these topology changes may require DER control methods and functions adaptation accordingly in order to maintain feasible power quality, voltage level and supply reliability in the distribution network. This paper presents a real-life case study from the needed adaptation of DER control schemes and functions after MV distribution network topology change from normal to back-up connection. The focus in the studied case is on MV network connected wind turbine (WT) control scheme adaptation after the topology change based on real measured data from the WT. In addition, the paper presents also simulations from potential future scenarios with centralized and distributed battery energy storage systems (BESSs) which could be also simultaneously utilized for the provision of local and system-wide services.

With accelerated adoption of long range electric vehicles (EVs) lightweight and highly efficient on-board chargers (OBCs) are desirable. At the same time, development of OBCs capable of operation with single and three phase (truly universal) input offers the most versatile charging solution to EV owners regardless of their access to the electricity distribution network. In this work, use of two bridgeless current-fed push pull converters with active clamp is proposed as a truly universal bridgeless single-stage AC/DC converter for on-board charging application. The building blocks of the proposed topology achieve soft-switching and operate in continuous conduction mode with constant switching frequency. The diode bridge is eliminated at the AC input, which results in a simpler thermal management and significant savings in conduction losses. Principle of operation for the proposed converter and details of the proposed control scheme are illustrated in this paper. Proper operation of the converter and effectiveness of the control are verified through PSIM simulation for a truly universal 360V 5.4 kW single stage OBC.

The pressure of climate change and the need for the adoption of renewable sources have led to a strong development of technology within microgrids (μG). The modular and scalable nature presents opportunities for the development of a new class of users in μG (i.e. the prosumers). The large-scale integration of small-scale renewable energy sources (SSRES) creates challenges for today's classic electricity distribution networks. The paper proposes a simulation method for optimal integration of prosumers to minimize active power losses in μG. For a deeper analysis regarding the influence of the prosumers on the μG power losses, 24 hour real load consumption and generation profiles are used. The study's findings show that a more effective μG operation by the optimal allocation of the PV panels on the μG can decrease the active power losses up to 35% in a day.

One of the most significant commodities of today’s world is energy. Energy usage depends on various factors such as season, day of the week, temperature etc. It is imperative that the distribution, transmission, and generation of electricity is effective while equally producing required results to electricity customers. With an expectation for increasing power outages in South Africa in the nearest future, there is a renewed focused on electricity distribution and consumption. This paper examines the electric load profile at a commercial location in Johannesburg, South Africa, for which the overall dataset (in KWh) is classified into four seasonal regimes: summer, spring, winter, and autumn. Two probabilistic models – normal and lognormal distributions – are applied to investigate the medium-term behaviour of the time series dataset over a period of two years, between 2019 and 2020. Results from this investigation suggest that normal distribution gives a better approximation to the seasonal datasets, except during the spring season. The lognormal distribution is observed to give minimal fitting errors during the spring season. Additionally, the load profile during summer and spring seasons are observed to exhibit similar characteristics, likewise, both autumn and winter seasons are found to exhibit the same trend for the same period.

Electric power distribution systems are often configured to operate radially and without islands. Radiance is important for the sake of improving system protection. Also, for legal reasons, distribution systems should not operate with islands. In this work, we present a procedure for generating radial configurations. In addition, the methodology proposed in this paper is able, through switches, to detect and remove configurations with islands. Tests were carried out in several systems and, after analysis, we can verify the efficiency and robustness of the proposed methodology even for large systems.

Smart metering is a modern topic with rapid and continuous development. Smart metering offers the advantages of software running systems in measuring and managing the building utilities such as energy, water, gas, etc. The design and development of an IoT-based smart energy meter with a realtime power monitoring system device has been reported in this study paper. System idea has been designed that will be used to monitor electrical parameters such as voltage, current, and power of household appliances with grid and solar power. The proposed system consists of a smart sensing unit that will detect the home electrical appliances used for daily activities by following different tariff rates. It will reduce costs for the consumers and thereby improve grid stability. For electricity tracking, there will be voltage and current sensors, microcontrollers, and Wi-Fi modules. Consumers will be able to access to see the power ratings through a smartphone app from anywhere and anytime. Finally, solar and grid power will be connected to the device as a power source. Furthermore, this measured power would be delivered directly to the electricity distribution office. They will even be able to make the electric bill from the office without going from one home to another. The power consumption will be tracked by the main distribution board in this research study.

The uncontrolled addition of renewables may result in complications in power grids unless they are correctly allocated. The problems happen when the rating of the connected renewables surpasses the maximum permissible level of renewables penetration, and this occurs when the system exceeds its maximum hosting capacity (HC) edge. In this paper, multi-objective particle swarm optimization (MOPSO) is employed for harmonic-constrained hosting capacity (HC-HC) maximization and active power loss (P loss ) minimization in harmonically distorted distribution systems. Type C filters are optimally designed to mitigate harmonic distortion. IEEE 519 recommendations are taken into account to achieve the acceptable harmonic distortion limits. Correction of the true power factor of lumped loads and improvement of the voltage at the point of common coupling are considered in accordance with the Egyptian electricity distribution code. The results obtained show the effectiveness of the proposed type C filters.

This paper aims to design a controlled voltage stabilizer to protect domestic appliances from voltage dips in electrical power distribution. Voltage dips are recurrent and become a concern for distributors and consumers. Voltage dips affect the power quality and can have a negative impact on the proper functioning of domestic appliances and other sensitive electronic equipment. Today, this problem has become central and recent measurements show that voltage dips can reach 35 to 40 % in some regions of Senegal. Therefore, this work is mainly focused on the design of a single-phase CVS, using control methodologies based on PI controllers that can effectively handle large voltage dips. The proposed controlled voltage stabilizer consists of a fully controlled AC-AC power converter, based on a single-phase boost rectifier connected to a single-phase PWM inverter with control laws. The design and the control laws adopted were carried out taking into account the characteristics of the electric power distribution, as well as the domestic loads. The robustness and effectiveness of the controlled voltage stabilizer are verified by carrying out simulations in the Matlab simulink environment in various operating cases using real measurements of voltages with different types of electrical loads. Simulation results confirm the effectiveness and robustness of the proposed stabilizer. Furthermore, it enables the protection of domestic appliances by keeping the voltage level stable within a specified range around the rated value regardless of voltage dips.

Utilities are looking for cost-effective solutions to improve the grid's power quality and stability. Applications of FACTS devices provide a popular and proven solution to reactive power compensation, mitigating grid instability, improving power quality and voltage stability. Amongst a plethora of FACTS devices, shunt controllers are the most sought-after power controllers in which the power electronics-based Static Synchronous Compensators or STATCOM is the popular state-of-the-art technology. The increasing penetration of distributed RE (DRE) based electricity generation plays a crucial role in supplying power to loads in remote areas, especially where the main grid system is inaccessible. Such areas are frequently suffering the problems of reliable power supply, power quality, and voltage instability. The Utilization of smart inverters based on dynamic reactive power compensation by Distributed-STATCOM (D-STATCOM) has enabled to qualitatively improve the end-user requirements in the electricity distribution system. The design and behavior of a simple filter assisted D-STATCOM for reactive power compensation during variation of inductive loads is the topic of this paper. A cost-effective ±200kVAr D-STATCOM armed with a novel output filter and improved PI controller employing the pulse width modulated (PWM) technique to IGBT based Voltage Source Converter is proposed to compensate reactive power requirement of loads and to improve transient and dynamic stability, limiting harmonic distortion within standard IEEE-519 limits. The proposed STATCOM design is simulated in Simulink/MATLAB, which confirms its satisfying dynamic reactive power compensation capabilities and low level of harmonic distortion.