13 research outputs found

    Implementation of ANFIS in Forecasting the Development of Renewable Energy in Indonesia in 2030

    Get PDF
    An important energy fuel for power generation is utilizing petroleum products such as oil and coal. The use of basic fuels is increasing every year and the main fuel reserves are getting depleted/decreasing. In driving a generator, alternative energy is needed whose sources will not run out and can reduce the use of petroleum derivatives. This source is new and renewable energy. To ensure the development of new and renewable energy, it is important to forecast the development of new and renewable energy in Indonesia in 2030 using ANFIS. The results obtained in predicting the development of new and renewable energy in Indonesia in 2030 are 3,369.79 MW

    Unique stroke-multiplicity of positive lightning in Malaysia

    Get PDF
    This paper presents the unique characteristics of positive lightning generated vertical electric field waveforms recorded in Malaysia. The focus of the study was the waveforms due to positive lightning and their number of return strokes in a flash. A total of 172 lightning ground flash records were analysed, out of which 57 flashes contained positive lightning with a number of them having high numbers of subsequent return strokes which is somewhat unusual with observations elsewhere. The field measurements were done by using a parallel plate antenna coupled with a recording system. In contrary to the majority of positive lightning return strokes that has been recorded previously, where the average multiplicity is one, this study showed an average multiplicity of 3.86 which is almost four times higher than that is usually observed

    Characterization of measured lightning electric fields observed in Malaysia

    Get PDF
    This paper presents a characteristic of lightning electric fields. The lightning electric fields captured by two parallel plats sensor and the characterization for preliminary breakdown pulse (PBP) and first return stroke (RS) were studied. A total of 207 data were recorded and 10 data are selected and been utilized in this paper accordingly. In PBP signal data, time before return stroke, ending time and maximum peak of PBP were analyzed. The time duration between the PBP and the occurrence of RS was obtained as 0.64 ms and 2.61 ms and then compared with results from other researchers. For RS signal data, slow front time, deviation time, RS peak, time to peak, zero crossing time and 10% to 90% rise time were evaluated meticulously and the results were discussed accordingly. Moreover, the statistical correlation between electric field zero times and corresponding rise times was studied

    Comparison of lightning return stroke channel-base current models with measured lightning current

    Get PDF
    Electromagnetic pulse radiation produced around the lightning stroke channel has caused the disturbance to the microelectronic industry, especially to disturbance of high frequency to electronic systems. Lightning channel-base current function (CBC) characteristics and parameters determine lightning electromagnetic field (LEMF) results obtained on the basis of the used models. This paper evaluated and compared the measured lightning current and six lightning current-based channels models namely Bruce and Golde, Heidler, Diendorfer and Uman, Nucci, Pierce and Cianos and new current-based current (NCBC) models. In terms of the waveshape, among all the six lightning channel-based current models discussed, the models developed by Javor, Nucci and Diendorfer and Uman have showed a good agreement compared to the measured lightning current. In terms of 10-90% risetime and full width half maximum time (FWHM) comparison, NCBC and Nucci models have showed compatible comparison. However, Nucci model is not easily adjustable to different desired pulse-current waveshapes. On the other hand, NCBC model can be simplified, the values of lightning peak current and risetime can be chosen arbitrarily and independently from other parameters, and there is no need for the peak-correction factor, so that reduces the number of parameters. Therefore, the NCBC model was suggested to be used in the future in order to simulate much accurate return stroke model. This knowledge will contribute to the development of a new accurate and efficient return stroke model

    On the behavior of lightning return stroke current incidence to tall towers

    Get PDF
    The return stroke current in the case of a lightning strike on a tall structure is affected by different tower and channel parameters such as the velocity of the return stroke current, the height of the observation point along the structure, the lightning channel and the reflection coefficients at the top and bottom of the structure. This paper will consider all these factors in the behaviour of the return stroke. The current wave shapes at different heights along tower and channel were modeled and the simulated current at tower top was compared to the corresponding measured current. Moreover, the effects of reflection factors and other important parameters on the values of current peak were considered and the results were discussed accordingly

    The electric field effect on angles of copper-type down-conductor

    Get PDF
    This paper is to study the effect of electric field on an angle variation of copper down-conductor due to voltage and current transient. Down-conductor which informs of numerous material, shape and dimension are mandatory for diverting the lightning current from air termination system to the grounding system in sheltered building. Hence, a numerical analysis method is applied emulating the comprehensible and particular model according to ordinarily used in the manufacturer’s datasheet specification. A rigorous assessment in term of electric fields was reviewed in comparison with the critical breakdown value of air for a crucial study. Later, a foremost angle is proposed for the installation of down-conductor in order to achieve a reliable protection system

    Consideration of lightning current along a tall structure in the presence of horizontal arrangement grounding

    Get PDF
    The evaluation of the behaviour of lightning current along a tall structure is becoming an important issue when considering the lightning protection equipment required along a tall structure. This behaviour is affected by the element of the ground reflection factor which has a correlation between the impedance of the ground and the tower. The impedance of the ground is considered for a horizontal grounding arrangement while the impedance of the tower is assumed to be constant. Hence, the ground reflection factor can be given a variable value, whereas most of the existing literature assumes a constant value. When a constant value is entered into a calculation field, an inaccurate result is computed.In this paper, the lightning current along a tall structure under varying values of ground reflection factor and including the effect of the presence of a horizontal grounding arrangement has been considered and the results discussed accordingly. Modelling of the lightning return stroke current along a tall structure was undertaken by entering the calculated variable value of the ground reflection factor. The results indicated that a variable value of the ground reflection factor causes different peak values of the current and wave shape of the lightning current for different positions along a tall structure

    Effect Of Lightning Impulse Current On The Grounding System Model

    Get PDF
    The main purpose of the grounding system is to protect human, electrical appliance and building from electrical shock due to lightning or another form of electricity that hazardous. Therefore, to achieve this goal, the fundamental part must be taken into account. In this paper, a different 3-D orientation of concrete has been designed using Comsol software to analyze the performance of the electric potential of the injected impulse in different cases and position of grounding system modelled. In this study, few grounding systems was modelled, which consist of Full concrete, Three-quarter concrete, Half concrete and A quarter concrete to analyse the electric potential of the injected lightning impulse current to the performance of the grounding system modelled. From the result obtained, full concrete was chosen as the best orientation of concrete to be employed at the grounding site. This is because, full concrete has the lowest electric potential value compared to the other cases and position of concrete

    Modelling of lightning current in the case of striking to a tall structure

    Get PDF
    Lightning current is an important parameter that has to be considered. The different behaviour of lightning current depends on the way the lightning strikes either as a direct or indirect lightning strike. In this paper the modelling of the current as a result of a direct strike of lightning on a tall structure is considered. A few of up-to-date on current models, current functions, reflection factors, the return stroke velocity (RSV), the general equation representation of this case are reviewed. Also, through MATLAB software, the results of a case study are generated. The results show a good agreement with the measured values. In addition, the behaviour of the lightning current is evaluated at different heights of the lightning channel with respect to the top and bottom of a tall structure. Also, the lightning current at the top and bottom of the tall structure are observed for different values of the reflection factor. The results show that the peak of the lightning current along different heights of the channel with respect to the top and bottom of a tall structure decreases with increasing height of the channel. Also there is a time delay during the initial time period. Furthermore, the lightning current at the bottom of a tall structure has a high value of peak current and has an attenuation wave shape of current that compares with the lightning current at the top of the tall structure. As a result, this paper may provide benefit in evaluating the electromagnetic (EM) field since the behaviour of the lightning current on a tall structure is known

    Characterization preliminary breakdown in the measured lightning electric fields

    Get PDF
    In this study, characterization of measured electric fields due to lightning channel was done. Likewise, previous studies on this case were reviewed and discussed accordingly. Furthermore, preliminary breakdown was done in detail and it was indicated on the real measured electric fields and the results were discussed. The behavior of preliminary breakdown signal was observed. This study shows that it will be easier to design filtering of the preliminary breakdown. The result show compelling agreement with theoretical predictions and significant improvement over previous effort by Clarence and Malan, Weidman and Krider and Rakov, et al. the work presented here has profound implications for future studies of Preliminary Breakdown and may one day help solve the problem of designing protection level for Electrical Engineers. The results show that the occurrence of PBP is in between 2 to 10 milliseconds before return stroke as agreed with Clerence and Malan
    corecore