As the complexity of SoC increases rapidly, embedded memory becomes one of the critical components in current SoC design. In this thesis, we develop a memory generator so that users can easily integrate proper embedded memory circuits into SoC chips. The generator is based on a low-power multi-voltage-source memory architecture that partitions the complete memory into two parts to avoid unnecessary operations. In addition, we also address the modification of the memory architectures in order to provide more efficient data accessing in multimedia applications such as DCT, JPEG-2000 and 3D graphics. The developed memory generator can produce all the necessary files required in the traditional cell-based design flow, including behavior model, Synopsys library, LEF file, Spice netlists and layouts, so that the designers can easily utilize the generated memory units in their ASIC designs.

SAGE (Statement Analysis Grouping Evaluation) system is a statement-based parallelizing compiler designed for PIM (Processor-in-Memory) architectures. By extracting the potential parallelism and utilizing the capabilities of PIM architectures, this system can achieve better performance of the applications. It analyzes the source codes, transforms the codes, makes good executing schedule and generates the codes which can execute on PIM architectures. This thesis focuses on the implementation of the code generator in the SAGE system. The code generator can transforms the original source codes into subroutines according to the corresponding HBG (Hyper Block Graph) and execution schedule which is determined by the other modules of SAGE system. It generates subroutines, inserts necessary arguments, determines the positions of caller and callee and generates the interface program for executing on PIM simulator. The generated codes after our code generator are also discussed.

Thanks to the booming of car electronics in recent years, more car electronics devices are installed in ve-hicles. These devices are connected by in-vehicle communication networks. In this thesis, we present the tran-sceiver and clock generator design for the physical layer of a FlexRay-based in-vehicle communication protocol. Regarding the transceiver design, a LVDS-like transmitter is proposed to drive the twisted pair of the bus. By contrast, a 3-comparator scheme is used to carry out the required bit-slicing and state recognition at the re-ceiver end. The reliability and safety are the priority design factors for electronics. A robust 20 MHz clock generator with process, supply voltage, and temperature compensation, a sub-1 MHz oscillator, and a temperature detector are included in our clock generator design. All of these designs are implemented by using a typical 0.18 um single-poly six-metal CMOS process. The proposed prototypical transceiver has been tested by a thermo chamber to justify its operation in the required temperature rage, i.e., -40¢XC to 125¢XC. Moreover, the compatibility of our design is also verified in a real FlexRay-based network. The maximum throughput of the proposed prototypical transceiver can reach 40 Mbps.

In a Doubly-fed Induction Generator (DFIG) wind energy conversion system, the rotor of a wound rotor induction generator is connected to the grid via a partial scale ac/ac power electronic converter which controls the rotor frequency and speed. In this research, detailed models of the DFIG wind energy conversion system with Sinusoidal Pulse-Width Modulation (SPWM) scheme and Optimal Pulse-Width Modulation (OPWM) scheme for the power electronic converter are developed in detail in PSCAD/EMTDC. As the computer simulation using the detailed models tends to be computationally extensive, time consuming and even sometimes not practical in terms of speed, two modified approaches (switching-function modeling and average-value modeling) are proposed to reduce the simulation execution time. The results demonstrate that the two proposed approaches reduce the simulation execution time while the simulation results remain close to those obtained using the detailed model simulation.

In a Doubly-fed Induction Generator (DFIG) wind energy conversion system, the rotor of a wound rotor induction generator is connected to the grid via a partial scale ac/ac power electronic converter which controls the rotor frequency and speed. In this research, detailed models of the DFIG wind energy conversion system with Sinusoidal Pulse-Width Modulation (SPWM) scheme and Optimal Pulse-Width Modulation (OPWM) scheme for the power electronic converter are developed in detail in PSCAD/EMTDC. As the computer simulation using the detailed models tends to be computationally extensive, time consuming and even sometimes not practical in terms of speed, two modified approaches (switching-function modeling and average-value modeling) are proposed to reduce the simulation execution time. The results demonstrate that the two proposed approaches reduce the simulation execution time while the simulation results remain close to those obtained using the detailed model simulation.

No description available.

The aerospace and marine sectors are currently using or actively considering the use of DC networks for electrical distribution. This has several advantages: higher VA rating per unit volume of cable and ease of generator connections to the network. In these systems the generators are almost exclusively ac generator (permanent magnet or wound field synchronous) that are linked to the dc network via an electric converter that transforms the ac generator output voltage to the dc rail voltage.The main objective of this project is to develop a Homopolar DC Generator (HDG) that is capable of generating pure DC voltage and could therefore remove the need for an electric converter and ease connection issues to a dc electrical distribution network. The project aim is to design, build and test a small technology demonstrator, as well as electromagnetic modeling validation.In Chapter 1, the initial generator concepts proposed to fulfill the aforementioned requirements of DC generator are presented, as well as an obscurity in electromagnetic induction law faced at the beginning of this project. Also the advantages, disadvantages and different applications of Homopolar DC Generators are covered in Chapter 1. In Chapter 2, Faraday's law of induction and the ways of using it properly are discussed using some example. The preliminary design calculations to construct the prototype HDG are presented in Chapter 3. Also the prototype construction and assembly procedure are discussed in this chapter. In this project, magnetostatics and current flow Finite Element (FE) simulations were used to assess the prototype HDG. In Chapter 4, the results of 2D and 3D-FE simulation are presented; furthermore the limitations of the FE simulations to assess the HDG performance are included. In Chapter 5, the results of the practical tests are demonstrated and assessed, as well as comparison between some of the results obtained practically and those obtained using FE-modeling. Using sliding contacts in the HDG is obligatory so some definitions corresponding to electrical contact resistances are given in Chapter 5. Final chapter is conclusions including the results assessments, future works to design, simulation and construction of the HDG.

No description available.

Abstract Vattenfall is about to create a standard that will be used during inspections of their generators. The method chosen to create the new standard is to speak with people that works with the inspection of the generators. They have a lot of experience and knows how to interpret signs and when it is time to maintain the generator. The purpose is to see and take care of problems before they lead to a breakdown. That is made by using condition based maintenance. To estimate how to do the right assessment when noticing different behaviour of the generator was not the only problem. It is also difficult to understand what should be checked during inspection and there for a new inspection list has been created. To make data collection useful there must be a proper way in handling data. When handling data in a correct manner the opportunity to make the right decisions based on facts increase.

This thesis aims to simulate and find out more about the electrical dynamics of a six-phase exciter for hydropower generators. Because ordinary electric circuit-based simulation software only simulate three-phase electrical systems, a FEM-based software is used for the electrical dynamics simulations of the six-phase system. The objective is to analyse the pulsation behaviour of the rectified electrical output on the six-phase system and compare it to the three-phase system. The three-phase system is also simulated with filters with the aim of decreasing the amplitude of the pulsations on the electrical output. It is expected that an upgraded system from a three-phase system to a six-phase system should double the pulsation frequency on the rectified electrical output. However, the result shows that the rectified electrical output of the six-phase system consists of pulsations with unexpected frequencies. The simulated RL-filter on the three-phase system shows only insignificantly small changes on the rectified electrical pulsation amplitude.