Carpathian Journal of Electrical Engineering

7-21

Authors: Horatiu Dacian LASLO, Traian VARODI

Electricity, DC voltage - AC voltage, conversion generated from certain renewable energy sources such as photovoltaic panels should be made with quality factors imposed by the present standards. In the case of multilevel converters the achievement of reasonable distortion factor is realized by optimizing the targeted waveform using Newton Raphson method. This paper presents an optimization solution based on genetic algorithm. Voltage waveforms obtained by this technique and the total harmonic distortion degree of reduction are presented by comparing the results obtained from supplying a consumer with a voltage generated in classical way through DC-AC conversion, using multilevel converter.

39-52

Authors: Lenin KANAGASABAI

This paper projects Fragaria Daltoniana Algorithm (FDA) to solve optimal reactive power dispatch problem. Fragaria Daltoniana plant develops sprinter, roots for spread and pursuit for water resources & mineral deposit. In Fragaria Daltoniana plant sprinter, roots are whispered as implement for global and local searches. The planned Fragaria Daltoniana Algorithm (FDA) will replicate the computational agents at all iterations, revealing all agents to both minute and big movements from the begin to end & data exchange between agents. The proposed Fragaria Daltoniana Algorithm (FDA) has been tested on standard IEEE 30 bus test system and simulation results show evidently the better performance of the projected FDA in reducing the real power loss & enhancement of static voltage stability margin.

69-86

Authors: Emmanuel Asuming FRIMPONG, Elvis TWUMASI

Awareness of conservation and safety issues regarding electrical energy use among students is critical. This study has determined the level of electricity conservation and safety awareness among senior high school students in the Ashanti Region of Ghana. The study was carried out through the administration of questionnaires to eight hundred and eighty-three students in five selected schools in the study region. The study assessed awareness levels based on gender, programme of study and academic study level. The questionnaires were developed to establish student’s knowledge of specific energy conservation practices relating to various consumer appliances, their motivation or otherwise to support institutional efforts to reduce energy consumption as well as their awareness of specific issues regarding electric shocks and electric fires. Analysis of the administered questionnaires point to the fact that a very high percentage of the students in all the three categories considered are aware of most of the issues presented to them. Also, a high percentage of them are inclined towards factors that motivate energy savings. Of the categories evaluated, females, students in the first level of study, and those studying Home Economics had the highest average awareness levels. The findings of this study will be very useful for educational campaigns concerning electricity use.

99-113

Authors: Francis EFFAH, Philip OKYERE, Patrick WHEELER, Alan WATSON, Jon CLARE

A modified virtual space vector modulation approach for the control of a Z-source neutral point clamped inverter is presented in this paper. This approach works perfectly for the traditional neutral point clamped inverter. In this paper, the effectiveness of the virtual space vector modulation technique in balancing the input capacitor voltages of the Z-source NPC inverter with no low-frequency oscillations superimposed in addition to voltage buck-boost capability is demonstrated through simulations in SABER®. A prototype converter is used to capture experimental results for validation.

124-133

Authors: Mihaela ŞTEŢ

Electricity is justly considered today as an indispensable factor of existence and development of society. Besides its incontestable benefits, there can be revealed some forms of environmental impact that, to a greater or lesser extent, create concern amongst specialists, as well as among the general public. The paper proposes an analysis of the impact on the environment of the electricity, starting from the different forms of production of electric energy, presenting also the negative environmental effects of transport, distribution, and use of electricity.