Design optimisation of 275 kV self supported lattice steel transmission tower using linear static and p-delta analyses

• Main Author: Siti Aisyah Binti Kamarudin
• Format: text::Thesis
• Language: English
• Published: 2023

Self-supported lattice steel transmission tower was functioned to carry a heavy transmission conductor at a sufficient safe height from ground in order to be safe and fulfil demand from time to time. Until now, the highest demand for electricity recorded in Peninsular Malaysia was 18.566 megawatts (MW) during April 2019 as stated in Tenaga Nasional Berhad Annual Report 2019. The total length of domestic transmission network recorded in peninsular Malaysia was 23,964 km, with the total transmission substation of 456 stations. The importance of lattice steel transmission tower to transmit the electricity especially for the main transmission line 132 kV – 500 kV made it essential to Nation as it can cause a major disruption in power supply. In order to sustain the service, a very strong transmission tower was needed. However, land acquisition prevented it to occur as most of the crucial transmission towers located at remote and congested areas. The idea of upgrading and strengthening the existing transmission tower to overcome the issue and fulfil the energy demand was an alternative instead of constructing a new one. A design of a lighter and stronger transmission tower can be developed based on ASCE 10-15 Manual Guidelines. Thus, the aim of this study is to achieve an optimal design by using optimisation approach in term of displacement, stress distribution, weight, compressive strength and member utilisation. This study involved two objectives which are to evaluate structural behaviour of lattice steel transmission tower subjected to various loading conditions and to develop an optimal design of the lattice steel transmission tower by using optimisation approach. The study was begun with comparison analysis between linear static and p-delta analysis and behaviour of the original transmission tower was examined. It then continued with optimisation process where here 25 tower models were developed and undergo the optimisation method by modifying arrangement and member sizes of the transmission tower. At the end of this study, a results of transmission tower’s behaviour subjected to several parameter was presented. It found that Model KDT-01 has the optimum reading in term of displacement and stress value among all. It was also found that the Model KDT-01 averagely has below than 60 % usage of main member utilisation.