Real-time transient stability analysis by analog VLSI and transient stability enhancement

Two aspects of power system transient stability are discussed in this dissertation. The first one is the transient stability enhancement by generator tripping and the second one is the application of analog Very Large-scale Integrated (VLSI) circuits in real-time transient stability analysis.; Generator tripping is one of the most effective control means to enhance the transient stability. In this dissertation, an on-line generator tripping method and an off-line generator tripping method are studied, respectively. A hybrid method is proposed to combine the advantages of the on-line method and the off-line method.; The conventional method for transient stability analysis is to solve the generators' swing equations using the step-by-step method. Currently, available digital hardware is not fast enough for the real-time transient stability analysis. In this dissertation, the method to utilize analog VLSI circuits to accelerate the transient stability analysis is presented. Firstly, the analog models of the generators' swing equations, the transmission line network and the loads are presented, respectively. Then, the study moves down to the circuit level. The detailed implementations of circuit blocks, such as sine shapers, transconductance amplifiers and multipliers, are discussed.; Finally, two important issues in manufacturing a commercial analog VLSI chip for transient stability analysis are addressed. The first issue is the poor simulation accuracy that results from the large passive component deviations. The accuracy is improved by employing switched-capacitor circuits, automatic tuning circuits and voltage controlled resistors. The second issue concerns the manufacturing cost. Either the parameters or the topology of the analog VLSI chip cannot be changed after fabrication. Consequently, designing and manufacturing a dedicated chip is required in order to perform the transient stability analysis for different power systems, which results in prohibitively high fabrication cost. To design a generic analog VLSI chip that can perform the transient stability analysis for various power systems, the parameter reconfiguration ability of an analog VLSI chip is introduced. The reprogrammable generator model, transmission line network model and load model are derived, respectively.