Applied Mechanics and Materials Vols. 799-800

Abstract: With the increasing amount of waste together with the high development of the country, the high amount of waste needed to be treated properly in order to lower the impact to the environment. Waste to Energy through incineration is considered as the appropriated technology to convert green and clean energy from discard matters, especially for the waste that has the mixing composition and has not segregate its composition in the developing country. Therefore, it is essential to simulate its combustion process to see how much of electrical power that can be generated and purpose the appropriated technic in order to improve its efficiency. This research deals with the process simulation of using incineration technology with high moisture content and low heating value in developing country. The simulation of 500 ton per day incineration technology was conducted by the unit operation in Aspen Plus^® program in order to forecast the capacity of electricity production and the contaminants in flue gas emission. It was found that, even high moisture content and low heating value of waste, incineration can be one of the solutions to dispose waste properly and can recover green and clean energy in the form of electricity ranging from 3.78-6.29 MW_e depending on waste’s quality. This green and clean energy recovery from waste could be used to reduce the using of fossil fuel in order to mitigate the emission of the greenhouse gas to atmosphere.

Abstract: This paper investigated the impact on the earthing systems of cabinets of Telekom Malaysia (TM) when subjected to dangerous voltages due to current injection from remote sources. TM have received numerous cases regarding the failures of their cabinets due to power related issues (PRI) as well as lightning. These failures may have occurred partly due to the existing earthing systems installations. This research aims to determine earthing impedance of 5 ohms or less of TM cabinets with respect to local soil conditions. Low impedance earthing is not easy to realize mainly due to the local soil resistivity, layering and structures. To achieve a low impedance of below 5 ohms as per Telekom Malaysia's requirement, three types of earthing electrodes were modelled and simulated using CDEGS computer simulation software. Results have demonstrated that the existing earthing system of 3 rods practice by TM is sufficient for areas of resistivity less than 500ٹ-m. Combination of rectangular and vertical rods for resistivity of 500ٹ-m above is the preferred choice of earthing. Analysis and discussions presented in this study can be used as a guide for TM for their cabinet installations. Results also highlighted that achieving less than 5ٹ does not constitute a safe earthing system. Other parameters have to be taken into account before ascertain which type of earthing to be used in a specific location of a TM installation.

Abstract: Power failures in a number of electric systems worldwide emphasize the importance of security of electric supply. Security of supply involves long term resource adequacy and medium to short term generation reserve management. Generation reserve requirements are usually determined using empirical rules considering the demand as a deterministic quantity. Ignoring randomness could lead to suboptimal decisions. The research presented here differs from that prevailing in the literature by considering the demand as a random variable following a doubly truncated normal distribution this has the advantage of allowing considering day to day and seasonal variations. In this paper two new mathematical models are presented to determine generation reserve requirements for a market in which the regulator imposes an extremely high load curtailment cost in any unmet demand and delegates the role of buying generation reserves on the generators in a secondary market. These models are helpful tools to study analytically or by numerical simulation the interactions between the two markets. A potential scope for application of the proposed models is presented for the Colombian electric market.

Abstract: Capacitor banks are used widely in many different regions. Since seismic requirements are different from place to place, custom design is needed. Finite element simulation is used to help designers in this paper. All mechanical response of capacitor bank in different load cases are calculated. With these simulation support, custom design of capacitor banks is done for different regions safely and effectively.

Abstract: At present, the quality inspection of drilling holes in power transmission line foundations is mainly completed by manpower with the help of the measuring rope, reinforcing cage, etc. This is a rough measuring method with low accuracy, and even the workers have to enter into deep holes to measure verticality and similar values, which brings danger to personal safety. The measuring equipment and methods for foundation holes have mature application in the industry and civil building sector, which are mainly divided into two categories, contact and non-contact measurements. The inspection methods for drilling holes in power transmission line foundation are to be proposed by referring to inspection means used in the sector.

Abstract: This paper discusses the use of centralized control method in an Intelligent Energy Management System (iEMS) to prevent voltage violation after load transfer between distribution feeders with high PV penetration level. The proposed method comprises three control modes with different control algorithms for regulating both reactive and active power output of PV inverters in a distribution system with multiple PV installations. Before the execution of load transfer, the total reactive power compensation required at the critical Point of Common Coupling (PCC) is solved by the reactance of distribution feeder line segment to prevent system voltage violation. With the proposed control algorithms, the iEMS dispatches total reactive power compensation among PV systems according to the reactance of line segment and issues the control command to each PV inverter for adjustment of PV power generation so that the ancillary service of voltage support can be provided by all PV systems in a fairer manner. A practical Cimei island distribution feeder pair is selected for computer simulation to verify the effectiveness of the proposed control method after load transfer between two feeders.

Abstract: Electrical Distribution systems that are radially configured with one utility power source are inherently exposed to higher rates of outages and interruptions, due to failures of system components, including: transformers, breakers and switching devices. In addition, fault conditions can also be caused by weather, animals or human error. Historically in Saudi Arabia, many industrial and residential distribution networks suffered from these problems. Large-size, growing demand and cost — with the time requirements for enhancement projects — results in distributed generation (DG) — as online or backup —playing a key role in the residential, commercial and industrial sectors of the power system. In this paper, the value of DG — installed as an online power source for typical industrial distribution network in Saudi Arabia — is quantified by reliability indices that include System Average Interruption Duration Index (SAIDI), Customer Average Interruption Duration Index (CAIDI) and Energy Not Supplied (ENS). The study outcomes will provide power system engineers with the reliability benefits of DG penetration and an approach to assessing its installations, based on different factors such as size and location.

Abstract: The unequal leg transmission tower in mountainous areas of 5B-ZBC4 is based to establish the finite element model of three transmission tower and four wire line system. To further study the transmission tower under wind load displacement response, firstly using ANSYS analysis of the dynamic characteristics of the tower-line system. Then, taking the power spectrum of Kaimal wind speed and simulating the curve of wind speed of transmission tower line system in mountainous areas, considering the different elevation and different sizes of wind load, to analysis the wind vibration response for the tower-line coupling system. The results indicates that the tower top displacement means of 1# tower, 2# tower, 3# tower is increasing along with the elevation changes in 0 degrees wind load; The 37 m/s is the critical wind speed of 3# tower of transmission tower line system.

Abstract: The suddenly break makes the tension of tight lines rapid realease. The tower system will be subject to impact,but the design specification considers the break load only by static load.Beacuse of the angle between the sides of the transmission lines and the span changes, In order to solve this problem this paper uses the finite element program ANYSY/LS-DYNA to build tower and lines system model and analyse the dynamic response of corner tower system in role of lines breaking by the numerical simulation. The study has shown that the effect of the corner to the corer tower disconnected power respose can not be ignored.

Abstract: As transmission tower system has the characteristics of large-span and spatial truss structure, the study of the reliability is also developed on the basis of space truss research and large-span structure system. As simple and suitable, RSM (response surface method), in particular, quadratic response surface without considering the cross term is often used in reliability calculation. However, strong nonlinear limit that corresponding to a complex surface, the accuracy of quadratic response surface is inadequate, causing greater reliability estimation error. High-order response surface solves it well. To this end, based on univariate analysis of multivariate function, a reasonable algorithm as to assure that the form of higher-order response surface is proposed; on the algorithm is verified by given examples, the result shows better accuracy and efficiency .