2022 14th Electrical Engineering Faculty Conference (BulEF)最新文献_第8页

A Background Research Behind the Development of a Straw Pellet Burner 秸秆颗粒燃烧器开发的背景研究

2022 14th Electrical Engineering Faculty Conference (BulEF) Pub Date : 2022-09-14 DOI: 10.1109/BulEF56479.2022.10021204

Orlin Tomov

引用次数: 0

Environmental and Health Challenges in Battery Recycling in Bulgaria 保加利亚电池回收中的环境和健康挑战

2022 14th Electrical Engineering Faculty Conference (BulEF) Pub Date : 2022-09-14 DOI: 10.1109/BulEF56479.2022.10021161

Nikolai Vitkov

{"title":"Environmental and Health Challenges in Battery Recycling in Bulgaria","authors":"Nikolai Vitkov","doi":"10.1109/BulEF56479.2022.10021161","DOIUrl":"https://doi.org/10.1109/BulEF56479.2022.10021161","url":null,"abstract":"The purpose of this report is to investigate and compare the environmental and health risks of the selection of chemistry for electrical energy storage in Bulgaria at the end-of-life stage of the batteries and the inevitable decommissioning that must be followed by safe transportation and recycling. According to National Plan for Recovery and Sustainability of the Republic of Bulgaria, version 1.5 of 06.04.2022 [1], is expected to be generated large quantities of hazardous waste from electric batteries in the not too distant future. The choice of battery chemistry is determinant for the recycling procedures of these wastes. Two battery chemistries considered most promising for stationary electrical energy storage - Lead Acid (LA) and Lithium-ion-Iron (Ferrous) -Phosphate (LFP). Lead-acid chemistry is well developed in the western world, including Bulgaria, and would be a logical choice, but is many times less efficient than lithium chemistry, which can only be imported from the major producers in the East. The recycling of the waste from the two chemistries is fundamentally different - the lead chemistry can be recycled in Bulgaria in compliance with environmental and health standards or in neighboring European countries, while the lithium is likely to be recycled where it is produced (if there will obtain technological breakt$h$roug$h$) - in a country in the Far East with the corresponding transport and processing costs to be budgeted in the financial assessment of the projects. Unless a technological breakthrough occurs, there remains disposal of LFPs batteries with a high risk of large-scale explosions and fires at disposal sites with the risk of harm to people and severe environmental consequences.","PeriodicalId":375606,"journal":{"name":"2022 14th Electrical Engineering Faculty Conference (BulEF)","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130376544","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Supply Voltage Control Using Booster Transformers 用升压变压器控制电源电压

2022 14th Electrical Engineering Faculty Conference (BulEF) Pub Date : 2022-09-14 DOI: 10.1109/BulEF56479.2022.10020198

Y. Shopov, S. Filipova-Petrakieva

{"title":"Supply Voltage Control Using Booster Transformers","authors":"Y. Shopov, S. Filipova-Petrakieva","doi":"10.1109/BulEF56479.2022.10020198","DOIUrl":"https://doi.org/10.1109/BulEF56479.2022.10020198","url":null,"abstract":"In some situations, the electrical consumers are supplied by the reduced power supply voltage. According to the standard, the permissible variation of its effective value is $+/-10$ % of 230 V. However, in some small rural villages remote from the power supply it may be reduced to 150 V. In this case the increase in the nominal values can be realized by the use of booster transformers, so the supply voltage is kept within the acceptable range of variation defined in the standards. In this paper, a solution to control the supply voltage with a step of 5 % between 5 % to 35 % is suggested. It is realized by three transformers with secondary windings connected in series to the network voltage. When the voltage is within the acceptable range, the transformers are switched off. When the voltage supplied to the consumers falls below the permissible value, switching off one, two, or three of the transformers is carried out. As a result, additional voltage is added to the network supply. This ensures that the supply voltage is always within the acceptable range. A problem of the functioning of transformers is the switching between on and off state. During the commutation, they are in “a current transformer” mode. It means that unacceptable over-voltages, including insulation breakdowns, are possible. In this paper, a solution to this problem is proposed and an analysis is performed to study the progress of transient responses in the circuit related to the primary of the transformer. The efficiency of the suggested solution is confirmed by simulations with software OrCAD PSpice 9.1. The results of the simulations confirm the reliability and effectiveness of the under-voltage compensation solution.","PeriodicalId":375606,"journal":{"name":"2022 14th Electrical Engineering Faculty Conference (BulEF)","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127492356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

New Control Paradigm and Dynamic Pricing Scheme for Low Voltage Direct Current Networks 低压直流电网新控制模式与动态定价方案

2022 14th Electrical Engineering Faculty Conference (BulEF) Pub Date : 2022-09-14 DOI: 10.1109/BulEF56479.2022.10021152

R. Stanev, Dimo Siderov, Kostadin Viglov, V. Efthymiou, S. Khadem, C. Charalambous

引用次数: 0

Study on Influence of RL Load on the Operation Conditions of Capacitor Banks in a TCSC TCSC中RL负载对电容器组运行状态影响的研究

2022 14th Electrical Engineering Faculty Conference (BulEF) Pub Date : 2022-09-14 DOI: 10.1109/BulEF56479.2022.10020205

Milen Duganov, V. Gyurov, P. Parushev

引用次数: 0

Investigation of the electromagnetic field of marine high-voltage power transformers regarding the safety of the ship personnel 船用高压电力变压器电磁场对船舶人员安全的影响研究

2022 14th Electrical Engineering Faculty Conference (BulEF) Pub Date : 2022-09-14 DOI: 10.1109/BulEF56479.2022.10020201

M. Ivanova, Emil Barudov

引用次数: 1

RESEARCH OF THE FORCE EFFECT ON THE ROTOR WEDGES IN SYNCHRONOUS GENERATORS 同步发电机转子楔块受力效应研究

2022 14th Electrical Engineering Faculty Conference (BulEF) Pub Date : 2022-09-14 DOI: 10.1109/BulEF56479.2022.10021195

R. Spasov, P. Rizov, V. Petrov

引用次数: 0