| The Dynamic Braking Technique has many advantages, such as simplification of application and control, effectiveness to cost and lower maintenance. As a result, it has recently been deployed in many power systems to enhance their stability margin. In these applications, Braking resistors help damp both oscillations and swings of the power systems. Since the development of the Flexible AC Transmission Systems (FACTS) technique, the Thyristor-Control Braking Resistor (TCBR) which has the capabilities of rapid action and accurate power control has become an effective device for power system transient stability augmentation.; This thesis investigates a novel approach of devising control schemes for the TCBR systems without precise mathematical models. In accordance with accepted methodology, the transient characteristics of a power system could be determined from its operating conditions. Through these characteristics, the accelerating factors that result in the acceleration of the system could be obtained. The thesis first introduces an effective method to determine the accelerating factors of power systems based on their transient characteristics. Using this method, a TCBR control approach is proposed, from which, both conventional and fuzzy control strategy are presented. This thesis also discusses the design and modeling of the new controllers for the TCBR system. Moreover, two power system Simulink models are built and used to test the performance of the controllers.; Within the framework of power system stability and control, one of the contributions of this thesis is the introduction of a novel Equal Area Criterion (EAC) based TCBR control approach, which enhances the power system transient stability. In comparison with traditional Dynamic Braking method, the EAC based approach result in shorter settling time and smaller magnitudes in system swings. |
