Power Electronics has been identified as a high priority area for investment by UK and EU due to its pivotal role in delivering many low carbon technologies from electric vehicles to renewable energy generation, and distribution and Smart Grid implementation. Up to £18million over next six years is being made available, from the EPSRC Engineering, Energy, ICT and Manufacturing the Future themes, to support research in this area by creating a flagship programme to establish a multi-site virtual Centre of Excellence in Power Electronics.
Changes in the nature of energy use are yielding new opportunities for the application of power electronics. Questions about environmental emissions, security risk and waste disposal are pushing fossil fuel and nuclear electrical power plants out of favour, and bringing alternative energy conversion technologies, such as photovoltaics, wind turbines and fuel cells to the forefront.
My driving belief is that technology as a whole should be used in the service of humanity. Applied properly it will enhance health, education, safety, justice, and economic equality. Many of these emerging social technologies will rely heavily on development of efficient and environmentally friendly electrical/electronic systems. The work being undertaken in the 42V automotive power system is an initial step towards developing more efficient, compact and environmentally friendly electrical/electronic systems using the current advances in power electronic devices to replace the pneumatic and hydraulic systems. In the short term I am planning in developing a holistic 42V/14V electrical system for automotive applications. However, the complexity of the project stands with its applications rather than with the technology itself.
Changes in the nature of energy use are yielding new opportunities for the application of power electronics. Questions about environmental emissions, security risk and waste disposal are pushing new fossil fuel and nuclear electrical power plants out of favour, and bringing alternative energy conversion technologies, such as photovoltaics, wind turbines and fuel cells to the forefront. Power converters are integral to all of these systems and devices. Fundamental to the success of these emerging markets is the ability of the power electronics industry to consistently meet the demands of these new applications. Substantial opportunity exists for wide spread application of electrical power converters if they can be made low cost, reliable, rugged, serviceable, and interchangeable.
The current state of power converter design and manufacturing is seen to impede an ability to mass customize products for a variety of applications. While most converters are based on a few common topologies, they are designed on a custom basis. The design process typically requires performance tradeoffs between circuit topologies, semiconductor devices, control, EMI, heat transfer, packaging, interconnection, reliability, etc. Perpetual re-engineering typically produces converters that have reliability indices that are not definitively known, are unserviceable, and economical only
My current work on electrical systems goes to the heart of research being conducted by the automotive and aerospace industries, to make it more environmentally friendly. It hinges on ways to replace current hydraulic and pneumatic systems with electrical ones, to make vehicles more energy efficient and reduce their impact on the environment. This would involve cars being fitted with a 42V power source to supply the changes, instead of the current standard 14V. In addition, the research undertaken is being fed back into teaching, with the undergraduates now developing many renewable energy sources projects such as solar powered model car.
42V Automotive power System:
DEVELOPMENT OF A NOVEL 5kW/42V INTELLIGENT CONVERTER FOR AUTOMOTIVE APPLICATIONS
Growing pressure on the automotive industry to produce cars with less exhaust emission, better fuel economy, and to save energy necessitated the introduction of higher voltage electrical power system to meet these requirements in short to mid-term. Already, various electric systems architectures have been proposed and investigated over the past ten years. To meet such growing demands, the automotive industry has to move to higher voltage and the 42V power-net system is the preferred option . The 42V is further processed by the interleaved six-phase dc-to- dc buck converter system to supply power to the conventional automotive loads that are expected to remain at 14V level as well as to absorb the peak transients on the 42V bus voltage. A special DC/DC converter is therefore needed to interconnect the 14V and the 42V DC buses in the car of the future. Automotive electronics place severe demands on the performance and price of power electronic components and making the development of a suitable converter a challenging task. See link to publications.
Computer Games Intervention with Mucus Clearing Devices for Cystic Fibrosis (CF) (University of Derby and Nottingham UniversityHospitals, NHS)
The funding for the project came from the University; a Collaborative Research and Development grant from the Healthcare and Bioscience iNet, which is funded by the East Midlands Development Agency (emda) and part-financed by the European Regional Development Fund; and a European Union Innovation Fellowship grant.
The aim of the is to design and create a suitable video game control and games, with the control based on a popular sputum clearance device. The device will include an air pressure sensor capable of sensing the intensity of the air flow to interface with the console/PC so that users can interact with the games. This will be the first phase of a longer term project with the initial objective being to prove our hypothesis that improved therapeutic benefit can be gained when performing the therapy through game play, when compared to using sputum clearance devices in the traditional way. A further objective is to identify the suitable aspects of game play which both mirror the devices normal usage and fully engage the patient.
- Pressure Sensor
- Signal Conditioning
- Power Supply
- Block diagram representation of the air flow pressure monitor system
- Mask (ASTRA)
The air flow pressure sensor consists of a mask, pressure sensor, signal conditioning, and a PIC microcontroller as shown has been developed.
EPSRC sponsored project: Integrated Electro-Thermal Modelling of Electrical Drive Systems
Power electronic systems have become essential features of the industrial market, with the power electronic devices themselves being operated nearer to their overload limit. Consequently the risk of adverse thermal conditions increases. An integral thermal model of drive systems has been developed for the IGBT devices. This involves analytical, simulation and experimental work. The model development is based on 3-dimensional Lumped Parameter (LP) and/or hybrid Lumped Parameter/Finite Element for accurate temperature prediction in an optimised simulation time. For the characterisation of the power electronic devices, tests were carried out to determine the thermal coefficients/characteristics and loss distribution which are of prime importance for accurate results prediction regardless of the method used in modelling. In addition, an investigation into the improvement in the thermal design, rating and efficiency was carried out.
Teaching Company scheme sponsored project: Design of a solid state frequency converter
The objective of the project is to design, develop and manufacture a solid state frequency converter to supply ground power to an aircraft in conjunction with Newton Derby Limited. This involved the design simulation and testing of a digitally controlled PWM IGBT inverter and rectifier.
Additional interests and activities
To provide Engineering students at the University of Derby with the up to date and industrially relevant skills I have instituted a range of strategies designed to stimulate student interest in Electrical and Electronic Engineering. A number of projects that I have developed sponsored by Research for learning and Teaching Fund, RLTF, are listed below;
1. Virtual Experiments - Derby - HE STEM Programme
The streamlining of resources, over the last couple of years, has impacted on programme structures and delivery at each level of the programme and resources. In addition, due to nature of programmes which incorporate both part time and full time students, the work load of students on the day of part time attendance is extremely high. With the virtual experiments, allows the remote access to laboratory equipment and instruments. This will enhance and facilitate the students' learning experience and comply with the University's policy of equal opportunity. Most engineering courses require laboratory intensive teaching. The required laboratory equipment is too expensive to be used irregularly and too cumbersome to move the equipment back and forth to other sites or locations. For STEM module, Power Electronics and Applications, the existing facilities are very restricted in capacity and for certain experiments the VE offers the flexibility and capacity in acquiring the practical skills needed by industries. For more information see the link: http://www.hestem.ac.uk/activity/virtual-experiments-derby
2. Design and build of an intelligent energy harvesting unit for charging portable electronic devices (RLTF)
Ultra low power wireless sensors are increasingly being used in medical, automotive and industrial applications such as security and health monitoring. As frequent battery replacement is impractical, it is advantageous to power the circuits with energy harvested from the environment. However, one of the disadvantages of the energy harvesting is the voltage provided by the sensor is often very low. Therefore, a DC-DC converter that can efficiently extract power from a low voltage source is critical. A paper on the subject ha been published at the International Convention cum Pre-Conference Workshop on Innovations in Engineering and Technology for Sustainable Development, 3 - 5 September 2012, BIT, India.
3. A Practical Approach for Teaching Power Electronics in Engineering:
Students undertake a practical power electronic design assignment that involves a model solar car race. The students are required to design, build and demonstrate a dc-dc converter that matches the output from a solar panel to a permanent magnet DC motor. This design and build solar car project makes use of some of the latest developments in instrumentation, power electronic devices, Matlab/simulink software and underpinned by research in Power Electronics and Automotive Systems conducted by the author at the University of Derby. The main objective of the project is to design a switch-mode, non-isolated, dc-dc converter with an adjustable duty cycle. The solar car project is structured as a team-based project. The students usually work in groups of three to four to ensure that they all experience some aspect of design, decision-making and teamwork. A team based project means that the students also gain experience in managing a project, and communicating effectively with others. A paper has been published in the UPEC, 2011.
4. Virtual Instrumentation Laboratory Experimentation System; Using a DC Motor control as a demo:
The system is built around hardware that is already available at the university, (DC Motor Control Module, LJ Technical Systems Inc). The developed software makes use of LabView which integrates both hardware and software. This has the advantage of the remote access to laboratory equipment and instruments via the internet.
5. A novel approach to the design and build of a variable power supply, (9-1.5V), to run various home appliances using power electronics and renewable energy sources:
The aim of this project is to design and build an intelligent power supply unit to run various home appliances using renewable energy sources such solar power. This project provides an immediate solution to reducing harmful emissions and economical benefits.
6. A Wind Turbine Project for Teaching Experimental Power Electronics in Engineering:
To develop an innovative project to capture and retain students' interest through the design and construction of a simple low cost dc-dc converter that would take a dc input of 40 to 70 volts from a wind turbine and create an output used to charge 12 volt lead-acid batteries.