Mott MacDonald

About: Mott MacDonald is a company organization based out in London, United Kingdom. It is known for research contribution in the topics: Electric power system & Wind power. The organization has 586 authors who have published 529 publications receiving 9801 citations. The organization is also known as: Mott MacDonald Group & MMD.

Sustainability and corrosion

Abstract: As a part of the drive to reduce carbon dioxide emissions, embodied energy figures are under consideration for construction materials. One aspect that needs to be included is the loss of embodied e...

Reliability assessment of offshore networks for connection of offshore windfarms

Abstract: This paper discusses the reliability assessment for offshore windfarms which is applicable for various offshore network design configurations The takes into account the overall risk associated with the offshore network and aims to calculate the availability level of the offshore network at one or multiple points of connections (6 pages)

Analysis of switching over-voltages in a three-ended 400 kV cable system

Abstract: The development of an electromagnetic transient model to assess potential transient switching issues on a proposed three-ended 400 kV cable circuit is described. The key features of the PSCAD-EMTDC simulation tool and the methodology of model development and testing are discussed. Typical study results and the overall conclusions drawn from these are presented. The paper demonstrates how analysis and modelling studies play an important role in the technical feasibility assessment and design of future infrastructure works such as substations and cable networks. The analysis confirms that it is feasible to operate the circuits as a three-ended arrangement via a simple T-point without overstressing the primary plant.

Weld Cooling-Rates and the Onset of Failure During “In-Service” Welding of Gas Pipelines

Abstract: Welding onto a live-gas pipeline (In-service welding or hot-tapping) is employed in the repair, modification or extension of gas pipelines and has significant economic advantages for the gas-transmission industry since it avoids the costs of disrupting pipeline operation and secures continuity of supply; and used in pipeline maintenance such as the installation of sleeves around damaged sections and direct deposition of weld-metal onto an active pipe to replenish wall thickness lost through corrosion or local damage of the gas pipelines. Unfortunately, the flowing gas results in an accelerated cooling of the weld; and secondly, the localized heating and loss of material strength during the welding process, since the pipe-wall may burst under internal pressure if this reduction in strength becomes too critical. The useful role of numerical simulation of ‘in-service’ welding has been demonstrated by earlier work (i.e. work of EWI & BMI, and Goldak & Others—1992) that applied a general 3D-finite element method to calculate the thermal fields for circumferential fillet and direct-branch welds. Earlier, current authors developed a preliminary burn-through model of ‘in-service’ welding and in this work the authors have attempted to increase the accuracy of thermal prediction.Copyright © 2005 by ASME