Ant Colony Algorithm (ACO) Applied for Tuning PI of Shunt Active Power Filter (SAPF)

In the present-day decade, the world has regarded an expansion in the use of non-linear loads. These a lot draw harmonic non-sinusoidal currents and voltages in the connection factor with the utility and distribute them with the useful resource of the overall performance of it. The propagation of these currents and voltages into the grids have an effect on the electricity constructions in addition to the one of various client equipment. As a result, the electrical strength notable has come to be critical trouble for each client and distributor of electrical power. Active electrical electricity filters have been proposed as environment splendid gear for electrical power pinnacle notch enchantment and reactive electrical strength compensation. Active Power Filters (APFs) have Flipped out to be a possible wish in mitigating the harmonics and reactive electrical electricity compensation in single-phase and three-phase AC electrical energy networks with Non-Linear Loads (NLLs). Conventionally, this paper applied Ant Colony Algorithm(ACO) for tuning PI and reduce Total Harmonic Distortion (THD). The result show reduces THD at 2.33%.

Ensuring Electrostatic Spark Safety for the Use of Fiberglass in the Process Pipelines, Apparatus, and Equipment

The number of the insulating materials, including fiberglass products, are widely used in the construction, industry, oil and gas facilities, agro-industrial complex, transport, and defense. When using fiberglass, like some other insulating materials, it is possible to encounter their destruction and perforation, followed by a transition to the source of double-sided corona effect. Sliding spark discharges of static electricity, capable of igniting a combustible or explosive environment, are also likely to occur. The formation of such discharges depends primarily on the electrostatic and electrical strength properties of the used materials. These parameters should be used when assessing the most dangerous consequences of the fiberglass application in the process pipelines, apparatus, and equipment under the conditions of electrification processes. Comparison of the electrostatic and electrical strength properties of the corona-forming air layer in the electrization processes with the similar indicators of non-conductive structural materials is the main criterion that determines the possibility of their perforation and the occurrence of spontaneous sliding spark discharges. Electrostatic intrinsic safety should be ensured by eliminating static electricity discharges that are capable to become the flammable substances source of ignition (materials, mixtures, products). Sliding sparks can be eliminated by managing the electrostatic load. But at the same time, the hazard of ignition by discharges would remain if they could occur. When replacing the metal element (the wall of an apparatus or vessel) electrified by a liquid (technological medium), a product made of an insulating material, including fiberglass, with similar geometric, technical, and operational parameters, it is possible to maintain the efficient protection of the metal structure by means of its grounding.

Methods for increasing the efficiency of shapers powerful microwave radiation in the task of electromagnetic destruction of a group of radio-electronic means.

Methods for increasing the efficiency of electromagnetic field shapers based on powerful microwave generators in case of electromagnetic defeat to a group of radio-electronic means distributed on the earth is surface have been determined. As an indicator of efficiency the radius of the zone of electromagnetic defeat of the most resistant radio-electronic mean was chosen. The limitations of the maximum power of the generator due to the finite energy of the power supply and (or) the electrical strength of the air in the radiating antenna are taken into account. It was found that the main methods to improve the efficiency of the electromagnetic field formers are the choice of the radiation parameters of the generator and the directivity characteristics of the radiating antenna. The optimal modes of operation of a microwave generator with a limited energy the power source have been determined. A comparison is made of the efficiency of shapers with different types of radiating antennas. It is shown that antennas with narrow toroidal radiation patterns are the most preferable for solving the problem under consideration.

Effect of Acetylated SEBS/PP for Potential HVDC Cable Insulation

Blending thermoplastic elastomers into polypropylene (PP) can make it have great potential for high-voltage direct current (HVDC) cable insulation by improving its toughness. However, when a large amount of thermoplastic elastomer is blended, the electrical strength of PP will be decreased consequently, which cannot meet the electrical requirements of HVDC cables. To solve this problem, in this paper, the inherent structure of thermoplastic elastomer SEBS was used to construct acetophenone structural units on its benzene ring through Friedel–Crafts acylation, making it a voltage stabilizer that can enhance the electrical strength of the polymer. The DC electrical insulation properties and mechanical properties of acetylated SEBS (Ac-SEBS)/PP were investigated in this paper. The results showed that by doping 30% Ac-SEBS into PP, the acetophenone structural unit on Ac-SEBS remarkably increased the DC breakdown field strength of SEBS/PP by absorbing high-energy electrons. When the degree of acetylation reached 4.6%, the DC breakdown field strength of Ac-SEBS/ PP increased by 22.4% and was a little higher than that of PP. Ac-SEBS, with high electron affinity, is also able to reduce carrier mobility through electron capture, resulting in lower conductivity currents in SEBS/PP and suppressing space charge accumulation to a certain extent, which enhances the insulation properties. Besides, the highly flexible Ac-SEBS can maintain the toughening effect of SEBS, resulting in a remarkable increase in the tensile strength and elongation at the break of PP. Therefore, Ac-SEBS/PP blends possess excellent insulation properties and mechanical properties simultaneously, which are promising as insulation materials for HVDC cables.

Experimental Studies of the Electrical Breakdown of Fire Extinguishing Powders

The method for determining the breakdown voltage in the air suspension of fire extinguishing powder, simplified and more appropriate to the actual conditions of such powders use is proposed and tested. Experimental studies of the electrical breakdown of fire extinguishing powders in an alternating electrical field — homogeneous and non-homogeneous are presented. Double effect of fire extinguishing powders on the breakdown in a homogeneous electrical field in comparison with air is established. The first option: powders to a small extent complicate the breakdown (increase the breakdown voltage), which is due to the high electrical strength of solid dielectrics. The second option: powders slightly facilitate the breakdown. Presumably, this is due to the abnormally high polarizability of one of the components — monoammonium phosphate (ferroelectric). Due to the avalanche-like polarization caused by the ferroelectric, the uniformity of the field is disturbed, which reduces its electrical strength. In an inhomogeneous electric field, the breakdown voltage was about one third lower than in a homogeneous one, and exactly corresponds to the breakdown voltage of the air. In a homogeneous field between the electrodes the «bridges» of powder particles containing monoammonium phosphate appeared and continued to hang even after the breakdown. An unexpected phenomenon was revealed: a relatively weak dependence of the breakdown voltage on the presence of moisture in the extinguishing powder. It is advisable to continue research in this area. The main conclusion: fire extinguishing non-conductive powder does not participate in the electrical breakdown that goes through the air between the powder particles. In view of this, the voltage of 1 kV seems an anachronistic one, at which the use of powder fire extinguishers is allowed, while for carbon dioxide fire extinguishers this figure is 10 times higher (though the electrical strength of carbon dioxide is 0.9 of the air electrical strength). Since the air electrical strength depends on the external conditions (temperature, pressure, humidity, distance between the electrodes), it is proposed to enter relative values for the assessment of the extinguishing powder electrical strength, for example, the ratio of the breakdown voltage to the breakdown voltage in the air.

Electrical Strength Estimation for Support Insulators under Pollution and Moistening Conditions

Based on the known theoretical concepts about the partial arc discharge development process and the data on the main design features of support insulators, numerical studies of their electrical strength under pollution and moistening conditions were carried out. The conditions under which the electrical strength of insulators can or cannot achieve its maximum possible value were analyzed. It is shown that the highest electrical strength of contaminated insulators is obtained at the optimal value of the ratio of the creepage distance to the height of the insulators along their insulating part (L/H)opt. The value of (L/H)opt is determined by the edge profile design features. As a rule, for insulators with a simple edge profile, the value of (L/H)opt = 2.45, and for insulators with a complex edge profile (L/H)opt = 3.1. In the region L/H ≤ (L/H)opt the effective use of the creepage distance by the discharge channel is ensured. It is shown that excessive increasing of the L/H ratio above the optimal value leads to inefficient use of the creepage distance by the discharge channel, which entails a noticeable decrease in the electrical strength of insulators. By using the proposed calculation estimates, it becomes possible to a priori determine the expediency of applying a particular insulator for being used in areas with various normalized pollution degrees.

Study of the electrical resistance, electrical strength and angle of separation of rice seeds from the drum surface

The article provides information on the “Dielectric” device for sorting seeds of agricultural crops and the results of theoretical research on seed sorting. The results of theoretical experiments showed that the diameter and number of turns of the working body of the device for sorting rice seeds in the “Dielectric” device, the expected result can be achieved by applying high voltage to the electrodes with opposite signals.