Majlesi Journal of Energy Management
Volume:9 Issue: 2, Jun 2020

In this paper an interleaved boost converter is introduced which has a high voltage gain and lower switch voltage stress than a conventional boost converter and has a different structure. Where only one group of active clamp circuits is required to provide both phases and absorb the energy of leakage inductance of the coupled inductance. The main switch and clamp switch are switched on and off during all switching transitions under ZVT, which reduces switching losses. The rate of reduction of the output current of the output diode is controlled by the leakage inductance, thus reducing the reverse recovery problem of diode. This converter is suitable for high frequency and power in high voltage applications. The proposed converter fully analyzed and operation modes are described. The converter is simulated with PSPICE software and the simulation results confirm the theoretical analysis.

This paper proposes a new interline hybrid unified power quality conditioner (IHUPQC) structure to improve the power quality of distribution feeders and to decrease the power ratings/voltages and switching losses of voltage source converters (VSCs). The IHUPQC consists of dynamic voltage restorer (DVR), an isolated dc-dc converter and a shunt hybrid active power filter (SHAPF) with a common dc bus. The inverse park phase locked loop (IP-PLL) technique is used to detect the distortions of signals in both feeders. Sinusoidal pulse width modulation (SPWM) based voltage control and current control are used for DVR and SHAPF respectively. The isolated dc-dc converter has PI controller based simple phase shift (SPS) technique. The performance of the proposed IHUPQC is evaluated through extensive simulations for mitigating voltage sag/swell and compensating current harmonics by using MATLAB/SIMULINK simulation tool.

The pandemic scenario caused by Covid-19 generated negative impacts in several countries, being one of the greatest disasters in recent years, not only related to health systems but also the economy. As a result, Brazilian energy companies were negatively affected, especially micro and small companies that have a large share of the country’s GDP and do not have, for the most part, structured management models and crisis management programs. Given this context, the present paper aimed to promote a discussion on how the best-structured management models influence the passage and survival of this category of companies in times of crisis and, thus, discuss how micro and small energy enterprises could react to the crisis caused by the coronavirus. After a process composed of searches for theoretical support already consolidated, reflections promoted evidence that a possible “way out” for the energy industry’s micro and small enterprises is flexibility in decision-making, focusing on understanding customers’ needs, and greater adherence to technology.

The following are some of the most important topics and security control strategies at various scales. Of course, some items can be removed on a smaller scale. Nevertheless, if security is very important, it is better to work on all of the following: Access control, Anti-virus and anti-malware software, Software security, Performance analysis and benchmarking and prevent leaks and information dissemination, Security information and event management and Virtual Private network and wireless network security & security web.

The present research is pioneering in reconfiguring a transmission network while taking into account the contingency ranking, transient stability, reliability, short circuit and loss. The existing algorithms have so far been used to reconfigure distribution networks and not yet used for the reconfiguration of over distribution and transmission networks with many closed loops. Thus, the present research aimed to use the graph algorithm for the transmission network. Here, we used reliable data from Khorasan network for three modes: low-load, medium-load and peak-mode. Based on the suggested algorithm, all meshes, simple and hybrid loops of multiple voltages were examined in Khorasan network at three levels, 63, 132 and 400 kv and three modes, low, medium and peak load. At the end, all estimations showed that open loops in the 63 kv network and closed loops in the 132 and 400 kv networks are the best operation modes in Khorasan network.

An infinitely low frequency (ELF) magnetic field is part of a radio wave with a frequency range of 3-300 Hz. The average exposure to a magnetic field in electrical jobs is higher than in other jobs such as office work. Scientists are still debating the interaction between magnetic fields generated bylines, posts, and other field-generating equipment with living organisms. To measure the magnetic field, the TES-1394 three-way measuring device was used. Field measurements were performed according to the 1994-644 IEEE std standard. At first, all sources of the magnetic field in the power plant were identified, then, in the vicinity of the sources of measuring stations were identified. The maximum and minimum values ​​of magnetic flux density were measured in generators’ vicinity (17.6µT) and 63 kV (1.03µT) power cables. The average magnetic flux density in the generator building sources’ vicinity was significantly different from other sources. The average ambient value of magnetic flux density at 230 kV (1.58µT) was higher than in other environments. The maximum exposure in occupational groups was related to the operators of generator halls (17.6µT). The results of field measurement of magnetic flux density in the vicinity of sources were consistent with other studies except for the control room. The maximum exposure in any of the job groups was not higher than the standard value.