Pervasive eHealth services a security and privacy risk awareness survey

The human factor is often recognised as a major aspect of cyber-security research. Risk and situational perception are identified as key factors in the decision making process, often playing a lead role in the adoption of security mechanisms. However, risk awareness and perception have been poorly investigated in the field of eHealth wearables. Whilst end-users often have limited understanding of privacy and security of wearables, assessing the perceived risks and consequences will help shape the usability of future security mechanisms. This paper present a survey of the the risks and situational awareness in eHealth services. An analysis of the lack of security and privacy measures in connected health devices is described with recommendations to circumvent critical situations

Dynamic series compensation for the reinforcement of network connections with high wind penetration

This study explores the use of TCSC technologies to improve the interaction between AC lines and VSC-HVDC links that form a parallel circuit. The purpose of this connection is the reinforcement of transmission paths that will facilitate the integration of new wind generation, such as the Dogger Bank, to the UK mainland electrical network

Multi-technology offshore wind power systems, control and dynamic performance assessment

This thesis presents a comprehensive study on the operation, principles and theory of wind farms consisting of doubly-fed induction (DFIG) and fully-rated converter (FRC) wind generators working together in a hybrid arrangement. The main objective of this study is to develop control strategies for the hybrid arrangement of wind turbines in order to improve the grid code compliance of the overall wind farm by exploiting the unique characteristics of both technologies to support each other in case of a fault happening. As a result, this thesis presents a novel control strategy for fully rated converter wind generators to improve the fault ride through capabilities of DFIG wind turbines during an AC voltage sag. The developed controller enables the creation of an environment where the FRC and DFIG technologies coexist for the purpose of compliance of grid code requirements. This type of environment can be created in both new wind farm developments and in already deployed DFIG-based wind farms where the addition of FRCs results in the overall improvement of the grid code compliance of the wind farm.The novel controller developed in this thesis uses the FRC to supply reactive power to the hybrid wind farm network during faults with the objective of reducing the magnitude of the voltage dip. This has positive effects in DFIG rotor speed and DC voltage variables during and after the fault period. These variables, as explained in the thesis, play a crucial role in stabilising the dynamic fault ride through capabilities of the turbine. Additionally, the novel controller developed in this thesis does not compromise the integrity of the FRC system.This thesis also contributes to the investigation of hybrid wind farms connected to the main grid using voltage source converter high-voltage direct current (VSC-HVDC) as a mean to increase renewable energy penetration and transmission capacity without affecting voltage stability or power quality of the specific case of the Great Britain's (GB) network. One main control approach was investigated on the sending-end converter to integrate offshore wind power from hybrid network where all generated power is injected to the point-to-point DC link with a stiff AC bus at the wind farm network. Additionally, two possible connection topologies of future VSC-HVDC were investigated for steady state and transient conditions. The operation of a multi terminal DC network (MTDC) for hybrid offshore wind farms is analysed with power flow studies of a 5-terminal MTDC model regulated by droop control.Finally, this thesis investigates three VSC-HVDC connections schemes designed to transfer 2.4GW of power from two separate Dogger Bank wind farms to the GB grid, in terms of the investment costs, controllability and reliability against expected scenarios. The benefits and drawbacks of all three scenarios are highlighted. These include the benefits of auxiliary cables on AC and DC site of the multi-terminal connections.This thesis presents a comprehensive study on the operation, principles and theory of wind farms consisting of doubly-fed induction (DFIG) and fully-rated converter (FRC) wind generators working together in a hybrid arrangement. The main objective of this study is to develop control strategies for the hybrid arrangement of wind turbines in order to improve the grid code compliance of the overall wind farm by exploiting the unique characteristics of both technologies to support each other in case of a fault happening. As a result, this thesis presents a novel control strategy for fully rated converter wind generators to improve the fault ride through capabilities of DFIG wind turbines during an AC voltage sag. The developed controller enables the creation of an environment where the FRC and DFIG technologies coexist for the purpose of compliance of grid code requirements. This type of environment can be created in both new wind farm developments and in already deployed DFIG-based wind farms where the addition of FRCs results in the overall improvement of the grid code compliance of the wind farm.The novel controller developed in this thesis uses the FRC to supply reactive power to the hybrid wind farm network during faults with the objective of reducing the magnitude of the voltage dip. This has positive effects in DFIG rotor speed and DC voltage variables during and after the fault period. These variables, as explained in the thesis, play a crucial role in stabilising the dynamic fault ride through capabilities of the turbine. Additionally, the novel controller developed in this thesis does not compromise the integrity of the FRC system.This thesis also contributes to the investigation of hybrid wind farms connected to the main grid using voltage source converter high-voltage direct current (VSC-HVDC) as a mean to increase renewable energy penetration and transmission capacity without affecting voltage stability or power quality of the specific case of the Great Britain's (GB) network. One main control approach was investigated on the sending-end converter to integrate offshore wind power from hybrid network where all generated power is injected to the point-to-point DC link with a stiff AC bus at the wind farm network. Additionally, two possible connection topologies of future VSC-HVDC were investigated for steady state and transient conditions. The operation of a multi terminal DC network (MTDC) for hybrid offshore wind farms is analysed with power flow studies of a 5-terminal MTDC model regulated by droop control.Finally, this thesis investigates three VSC-HVDC connections schemes designed to transfer 2.4GW of power from two separate Dogger Bank wind farms to the GB grid, in terms of the investment costs, controllability and reliability against expected scenarios. The benefits and drawbacks of all three scenarios are highlighted. These include the benefits of auxiliary cables on AC and DC site of the multi-terminal connections

Zero Energy Distributed Micro Pumped Hydro : Venturo Pump Performance - Technical Report

The aim of this project was to analyse the performance of Water Powered Technologies (Ltd) Venturo pump. Water Powered Technologies which are pioneering in ’zero energy’ water pumping technologies which deliver water flow based on kinetic energy conversion to pressures within a flow of water

Coordinated reactive power compensation strategy for doubly-fed induction generation wind turbines

Wind energy sector has gained the highest attention among all other renewable energy resources. The UK government has a target of 15% of its energy to be produced from renewable sources [1]. In 2016 wind energy contributed up to 10% to the UK’s total electricity supply [2]. Over the last 30 years wind technology has improved, and various wind turbine concepts and generators have been developed and enhanced. The increasing use of wind energy in the UK grid imposed the requirements for wind farms to comply with current Grid Codes as conventional power plants and contribute to the network support and operation. The future of the large scale wind farms may lay offshore and comprehensive studies in terms of controllability and reliability are required [3, 4]. Nowadays the leading generator technologies in large wind turbine development are the double-fed induction generators (DFIG) and the fully rated converter (FRC) [5]. From the controlled development point of view, both technologies share the same mechanical system dynamics, and similar controllers can be applied to each technology to attain control over the speed of the turbine. However, during AC faults, the dynamics of each wind turbine technology are different due to the distinct fault response nature of each machine as well as the different type of power conversion interface to the ac grid. During a fault condition the power electronics of the DFIG wind turbine are disconnected in order to protect partially-rated converter and control over the machine is lost. The DFIG also acts as an induction generator and consumes reactive power which does not comply with fault ride through capabilities. This work analyses the behavior of the DFIG and FRC under voltage dip. The two technologies are combined into a hybrid wind plant and a control method is proposed to support DFIG wind turbine during voltage dip by providing reactive power via FRC wind turbine. Fig. 1 shows simplified power system configuration of hybrid wind farm

Zero Energy Distributed Micro Pumped Hydro : Scottish Regional Appraisal - Final Report

The purpose of the ‘Scottish regional appraisal’ internal report prepared for Water Powered Technologies (WPT) as part of the Zero Energy Distributed Micro Pumped Hydro project (The Technology Strategy Board file reference 132394) aims to investigate the potential of large scale deployment of low-energy water pumping technology in Scotland. The potential deployment in the Scottish content of Venturo pumps which use kinetic energy of the flow with ‘zero-energy’ input from electrical energy to operate the pump is appraised in this report. This report is divided into three main parts. The first part of the report is focused on the “Application of the Venturo pump in rural industry: a case study of North East Scotland”, where the economic, social and environmental visibility of Venturo pump is assessed. It investigates the agricultural, food and drink industries, including breweries and distilleries businesses in order to provide the best guidelines for the use of ‘zero-energy’ pump in rural industry. Avenues of further investigation are highlighted. The second part of this report investigates the “Scottish financial framework” that looks at both opportunities and financial encouragements in Scotland potentially supporting WPT products. This section focuses on the energy saving potential of the Papa/Venturo pump and energy generation, storage and load balancing incentives. While the third part is a continuation of the financial framework, it primarily looks at Feed in Tariffs schemes (FiTs) for hydro generation. It reviews the principles and impacts of the FiT schemes and investigates four sites with hydro power potential which are downgraded due to different FiT bands and higher financial benefits. The difference in energy output between the unrestricted schemes and the restricted schemes can be considered as a loss of potential energy. There opportunities for Zero-energy pumps to exploit these gaps The last part of this report investigates the “Social Impact Assessment (SIA)” for ‘zero-energy’ water pump integration into water and utility facilities. It provides the pros and cons of SIA in the project development. The regulatory framework for Scotland, wider UK, Scandinavia, Ireland, Europe and Uganda have been discussed in this report

Cyber-physical-security model for safety-critical IoT infrastructures

The Internet of Things (IoT) and the number of sensors integrated within safety critical environments is increasing exponentially. System designers employ off-the-shelf hardware to reduce development time and cost, however, the early adoption of consumer hardware and software raises numerous security questions. Several successful attacks and threats to critical infrastructures have been reported. This paper reviews safety-critical applications in aviation, connected cars and power plants. An engineering development roadmap is proposed with cyber-security in mind from “cradle-to-grave” rather than an afterthought. The development roadmap introduces a cybersecurity review at each design step to strengthen the robustness of IoT hardware and software. However, considering these systems have an extremely long lifetime (>20 years), secure maintenance and integrity of ageing infrastructure is usually a secondary consideration. The paper proposes the use of a cyclic cyberphysical security model after system commissioning that allows knowledge transfer between regulatory bodies through sharing of best practices. The sharing will enable system operators to identify exploits encountered from other industries and maintain high security levels and improve the IoT architectures