Course syllabus for Electric drive systems

• design current, speed and position controllers of electric machines, based on bandwidth requirements of their performance, the parameters of the machine together with the load and the supplying power electronic converter.
• construct/develop a control system of a DC-machine and to judge the performance of the current and speed controller using a linear power amplifier.
• construct/develop a field-oriented control system of an induction machine and a PM synchronous machine and to judge the performance of the current and speed controllers.
• implement and evaluate active damping, feed-forward and anti-windup of the regulators.
• present currents, voltages and fluxes in 3- and 2-phase stationary systems as well as in the rotating 2-phase system, and to be able to move between these representation systems.
• derive, implement and judge the performance of the current model flux estimator in direct and indirect field orientation.
• derive the base equations of the voltage model flux estimator and evaluate the performance of the voltage model.
• derive the base equations for estimating the rotor position with signal injection for a salient PM synchronous machine and evaluate its performance.
• use the state-space representation for simulation of electric machines and be able to derive the state-space equations from the standard equation set-up describing an electric machine.
• describe how a three-phase converter operates and to determine the switching pattern that is created by the converter and the impact that this pattern has on the machine.
• design a field weakening controller for the machines.
• implement the developed control system on a drive system with a dSPACE real time control system and evaluate the drive system performance.
• describe how a Volt/Hz control operates.
• choose the relevant (environmental friendly) drive system for a given application with given specifications and to calculate its energy use.

Lectures and tutorials:
Mathematical transformations: Transformation of voltages, fluxes and currents between the physical 3-phase system and a fictive 2-phase system. Transformation of currents, voltages and fluxes between a stationary and rotating coordinate system.
Models of electric machines: Starting from the physical descriptions of the machine the equations describing electric machines are derived. Induction machines as well as permanent synchronous machines.
State-space modelling: Implementation of machine equations into a set-up that is suitable for computer implementation.
Controllers: Design of current, speed and position controllers using the Loop-shaping method. Design of anti-windup feature of the controllers.
Field-oriented control: Realisation of a dynamic high-performance controller for an electric machine utilising the field-oriented control idea. Both using indirect and direct field-oriented control.
Flux observers: Voltage and current model flux observer.
Sensorless control: Sensorless control means speed- and position sensorless control. The covered control structures for eliminating the need of these sensors are the voltage model flux observer and signal injection for the PM synchronous machine.
Power electronic converter: Realisation of control reference values into PWM-switched voltage patterns applied to an electric machine.
V/Hz control: Control structures suitable when the dynamic requirement of the drive is not high.
Field weakening: Usage of the field weakening method to increase the speed of the machine above the nominal speed.
Digital implementation: Implementation of the controllers on a dSPACE real time control system.

Project (compulsory):
The compulsory project covers the design, implementation and evaluation of high-performance drives for DC-machines, induction machines and PM synchronous machines. The project is divided into subtask, one per week, where each task covers the theory covered in lectures and tutorials for that week.