Many controllers incorporate programmable logic controllers PLCs rather than electromechanical components. The design synthesis of a -switched reluctance machine capable of meeting the required performance specification is particularly onerous given the harsh environment in which it operates, specifically in terms of the restricted space envelope, the high ambient temperature and the very high rotational speeds.
Once the current has risen above the set value, the switch turns off. The thesis describes in detail the electromagnetic and mechanical construction of the generator and presents a comprehensive survey of operating waveforms and performance measurements.
Download 87Mb Abstract The efficient generation of relatively large quantities of electrical energy in vehicles is becoming an increasingly important issue, as a result of increasing demands of ancillary equipment and the emergence of hybrid power-train vehicles. A microcontroller is ideal, since it enables precise timing of phase activations.
This sequence can also be reversed to achieve motion in the opposite direction. This thesis describes the design of a switched reluctance machine for a prototype system, a procedure that encompasses the detailed analysis of centrifugal stress in the rotor, aerodynamic losses, iron loss, rotordynainic performance and dynamic performance.
Overall, the research will aid in the development of the SRG by allowing user to choose the best generating operation within any speed range. Thirdly, the procedure to determine the optimal control variables is proposed.
Power circuitry[ edit ] Asymmetric bridge converter The most common approach to powering a switched reluctance motor is to use an asymmetric bridge converter. Lastly, a novel control method is proposed to operate the machine in single pulse mode as opposed to the current chopping mode during the low speed range.
The phases in an asymmetric bridge converter correspond to the phases of the switched reluctance motor. As at any time two coils are energised, First, stator poles A0 and A1 are energized.
Based on the framework, extensive and in depth comparative analysis can be conducted. More steps between positions with identical magnetisation, so the onset of missed steps occurs at higher speeds or loads.
It is possible to do this using electro-mechanical means such as commutators or simple analog or digital timing circuits.
A polynomial function relating the percentage of power generated in terms of the optimal control variables has also been developed. Current research on the SRG has been focusing on optimizing its performance individually in terms of structure, control and also reducing the components of power electronic devices.
It also enables a soft start function in software form, in order to reduce the amount of hardware required. This differs from the apparently similar induction motor that also energizes windings in a rotating phased sequence. Preview Download 45MB Preview Abstract The thesis investigates a high speed switched reluctance SR generator suitable for applications such as aerospace and turbo-charged ground vehicles.
It can be used to predict the performance of the machine before it can be implemented on a prototype, thus, saving time and costs. Simple switching[ edit ] If the poles A0 and A1 are energised then the rotor will align itself with these poles.
PhD thesis, University of Nottingham. This thesis is concerned with the design of a system, which extends this concept to enable both electrical generation and highly flexible air-management.
Electricity can be generated from the wind by using a variable speed machine. The main contribution of this thesis is the proposed modelling framework of the SRG. The rotor of the generator was mounted on the protruding shaft of an air turbine and extensive tests were performed at a variety of speeds and supply voltages.
Ebrahim, Mohammed Taha A very high speed switched reluctance generator. The rotor comprises 30 pm laminations of amorphous alloy chosen for its mechanical strength. Control[ edit ] The control system is responsible for giving the required sequential pulses to the power circuitry.
It is a solid salient-pole rotor having projecting magnetic poles made of soft magnetic material often laminated steel.Switched reluctance generator drive in the low and medium speed operation: modelling and analysis: a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Electrical Engineering at.
Information on the structure of considered drive system with reluctance motor, principle of operation and mathematical model of the motor, principle of the energy conversion in analysed system and elementary types of supply devices have been presented in initial part of the thesis in context of the large world wide bibliography.
Abstract: A Switched Reluctance Generator (SRG) system normally encompasses three main components: SR machine, controller and converter. Ongoing research on simulation and modelling of SRG system has focused on one component. There is a lack of a more comprehensive approach which integrates all three components into one simulation.
ripple, and efficient battery charging using the switched reluctance generator (SRG) is presented in this thesis.
Two different SRM models are simulated for controller. mainly consists of two major parts: control of a Switched Reluctance Generator (SRG) system and development of high-power dc-dc converters for a dc network system in a wind farm. The SRG, which eliminates permanent magnets, brushes, commutators, and coil windings in the rotor, could be a promising wind power generator.
The switched reluctance motor (SRM) is a type of stepper motor, an electric motor that runs by reluctance torque. Unlike common DC motor types, power is delivered to windings in the stator (case) rather than the rotor.Download