Postgraduate Prospectus

This module introduces the state-space representation of physical systems and the control design of multi-input multi-output systems using multi-variable control techniques for both continuous and discrete implementation. The module then covers both full and reduced observer design for those cases when state variables are not measurable. The module finishes with an overview of optimal control design. A more detailed design experience using advanced CAD will be acquired by means of a specialized coursework.

This module provides students with an understanding of the operational principles of power electronic converters and their associated systems. This module covers:

• 3-phase naturally commutated ac-dc/dc-ac converters
• capacitive and inductive smoothing - device ratings
• dc-ac PWM inverters and modulation strategies
• resonant converters
• high power factor utility interface circuits
• thermal management of power devices including transient thermal effects.
• simulation of Power converters using a suitable CAD package

This module provides students with an understanding of power systems which include renewable energy generators. It investigates the operation of renewable energy generators at a systems level, including analysis of distributed generation systems. The module covers:

• analysis of load flow in distributed generation systems
• operation and control of microgrids
• economic optimisation of renewable generators within a power system
• distributed power system control and stability
• Use of STATCOM devices
• Flexible AC transmission systems (FACTS)
• HVDC

This module considers the design and operation of Power Systems in a range or transport related applications

This module considers the design and integration of existing and future Power Electronic Devices. Power semiconductor devices: Introduction (review of electrical characteristics, physics); Power module construction (functional components, variants); Layout issues, stray inductance, partial discharge Passive devices: Capacitors (types, characteristics); Wound components Thermal management: Theory, developing thermal models; Analysis of gas and liquid-cooled systems (nat and forced convection) Reliability: Wear-out mechanisms; Optional practical - study of wear-out failures; Relibility testing/qualification; Reliability driven design and physics of failure; Analysis of wear-out mechanisms Integration: Introduction ; Schematic to system methodologies; CAD tools (use of); Packaging; Multi-functional components; Examples

The course will concentrate on modelling and control of power converters covering the following aspects and will incorporate the most recent technical developments where appropriate:

• Review of basic DC-DC converters
• Averaging techniques for modelling switching power converters
• Control techniques for the basic DC-DC converters (buck/ flyback) – voltage mode control/current mode control/effect of discontinuous inductor current
• Resonant DC-DC power conversion techniques - load resonant converters
• Modelling and analysis of load resonant converters - fundamental approximation approach.

This module addresses the control of AC drives and consists of a lecture component (10 credits) and a design and assessment project (10 credits)
The lecture component covers vector controlled induction motor drives and permanent magnet motor drives. Vector control is covered in depth covering the concept of space vectors, dq representation of 3-phase machines, dynamic equation structure and the concepts of direct and indirect flux orientation. Implementation of Indirect Vector Control, including current flux and speed control is covered in some detail and includes the effect of incorrect parameters.
Both AC and Brushless DC permanent magnet motor drives are introduced. The vector control concepts learned for induction machines are applied to AC PM machines. The concept of salient and non-salient AC PM machines are covered leading to the vector control using maximum torque per amp control strategies. Finally the field weakening control of both non-salient and salient PM machines are considered.
The project component is a design and simulation exercise using MATLAB/Simulink. The student is required to design an indirect vector controlled induction motor drive, implement the design in Simulink, and undertake evaluative tests covering current and speed loop performance, including field weakening for high speed. The exercise covers investigating the effects of parameter variation and designing engineered solutions to reducing the sensitivity.

This module provides students with an understanding of power system apparatus and their behaviour under normal and fault conditions. This module covers:

• concept and analysis of load flow
• voltage/current symmetrical components
• computation of fault currents
• economic optimisation
• power-system control and stability
• power system protection
• Power Quality

This module provides students with an understanding of the operational characteristics of common electrical machines (dc, ac induction, ac synchronous and stepping). Both theoretical and practical characteristics are covered. These include:

• Electromagnetic theory applied to electrical machines
• Principles and structure of dc machines - commutation effects
• Principles and structure of induction machines
• Principles and structure of synchronous machines
• Parameterisation for performance prediction
• Machine testing and evaluation

This module enables students to design both analogue and digital controllers for linear single-input single-output systems. Students have access to CAD control design packages for evaluating control design. This module covers:

• design of analogue controllers using Root Locus Method
• closed loop performance and frequency response
• microprocessor implementation
• practical problems in digital control
• design of digital controllers using z-plane techniques
• practice with CAD package.