Chen Y.,Atkins PLC |
White R.,Atkins PLC |
Fella T.,Atkins PLC |
Hillmansen S.,University of Birmingham |
Weston P.,University of Birmingham
IET Electrical Systems in Transportation | Year: 2016
Railway Operators and Infrastructure Owners are required to design the railway to specific national and international, technical and safety performance standards. These standards and codes of practice provide the basis for company 'Codes of Practice', which detail the design methodology, application and system installation. To validate the design and to comply with these standards and codes of practice, Atkins and the University of Birmingham have developed the multi-train simulator (MTS) to model AC railway electrification infrastructure. The development was carried out under a Knowledge Transfer Partnership between Atkins and the University of Birmingham. The MTS models multiple trains moving on AC traction railway networks following specified timetables. The model of the traction power network covers all types of AC feeding arrangements in the UK, including the rail-return system, the classic booster transformer system and the autotransformer system. This study addresses the work undertaken by the Knowledge Transfer Partnership and describes the development of AC railway electrification infrastructure modelling based on a multi-conductor model for MTS. The modelling of multi-conductors in AC power networks separately, instead of lumping them together, enables more accurate calculations of induced voltage, EMC analysis, return current distribution, positive and negative energy consumptions and loss calculations. © 2016 The Institution of Engineering and Technology.
Ferguson A.,Atkins plc. |
De Villiers P.,Carbon Trust |
Fitzgerald B.,Atkins plc. |
Matthiesen J.,Carbon Trust
European Wind Energy Conference and Exhibition 2012, EWEC 2012 | Year: 2012
It has been found that wind farms operating at higher inter-array voltages than is currently the norm will benefit from considerable cost reductions and higher yields. This paper highlights the potential for higher voltage inter-array systems to deliver significant cost benefit to the design of future offshore wind farms. A detailed comparison of 36 kV AC (operating at 33 kV) radial and ring inter-array systems with 52 kV AC (operating at 48 kV) and 72.5 kV AC (operating at 66 kV) radial and ring inter-array systems was undertaken. This involved an analysis of all key technical components of the system, i.e. cables, switchgear, transformers and offshore substations and optimising and comparing the inter-array designs. A detailed cost-benefit analysis was carried out in order to compare the systems. This included CAPEX, operation and maintenance, cost of system losses and cost of losses due to cable failure for an assumed wind farm lifetime of 25 years. A further qualitative comparison was performed to identify other risks and benefits, including supply chain, health and safety and operation and maintenance considerations. Finally, the optimal higher voltage system was identified and a roadmap was developed to identify the route to commercialisation. It was found that moving to either 48 kV or 66 kV demonstrated a material improvement in the full life costs compared with 33 kV, but that the improvement for 66 kV was the highest. Previous work has examined the potential for higher voltages (48 kV or 66 kV) to be used to connect wind farms without an offshore substation  but this is the first time that a full analysis has been carried out for the use of higher voltage inter-array systems for wind farms that are far offshore and still incorporate a high voltage AC (HVAC) or high voltage DC (HVDC) transmission system.
Silmon J.,Atkins Plc |
Evans R.,Atkins Plc |
Brownsword M.,Atkins Plc |
Nicholson D.,Atkins Plc
Systems Engineering | Year: 2015
A brand-new high-speed railway project such as HS2, currently under development in the United Kingdom, presents a requirements engineering problem that is similar to domains where Systems Engineering (SE) is more traditionally applied, such as an aircraft, but with some differences in system structure that preclude a direct mapping of routine techniques. With over 300 separate elements of design in the Country South portion of the route, fitting into roughly 20 categories and inheriting requirements at multiple levels, including location-specific constraints, it was considered necessary to implement a model-based solution to provide an adequate level of technical assurance by managing the requirements and their links to the design elements. A database tool with diagramming capability was used to create a visual traceability structure between the client's original requirements and the refined requirements. A layered model of the system architecture was used to apply requirements to the correct sets of individual design elements. From this combined requirements and architecture model, spreadsheet checklists were generated for designers to perform verification. The resulting data were then re-imported to the database and processed into a detailed report for submission to the client. The solution developed automates assignment of requirements traceability in order to provide exactly the right set of requirements for each deliverable on the route, which may consist of multiple asset types in differing combinations and with local requirements as well as more generic requirements assigned by equivalence. © 2015 Wiley Periodicals, Inc.
Khanna A.,ATKINS Plc
IET Conference Publications | Year: 2014
This paper presents performance of two charging current compensation methods used in commercially available differential relays. This paper appreciates importance of cable models on protection and settings application studies and on estimation of performance of charging current compensation methods. The problem is split in to a) Significance of Power Cable Modelling and b) Protection performance evaluations. Models available in EMTP-RV are considered. Transient performance of each of models is evaluated to determine which are most suitable for protection application studies. Single core, 3 phase, 132 kV crossbonded cables of various lengths are considered. However, the methodology can be extended to any cable arrangement including pipe type/Multicores cables. Single and three phase external faults are considered. Such a study would be useful for long cables i.e. in offshore transmission system and in densely populated urban areas where land costs restricts the construction of overhead lines.