Search

This paper presents the methodology for design Takagi-Sugeno controller to mono-machine power system in order to study transient stability under severe perturbation. The nonlinear system is modeled and transformed on linear fuzzy model. Then, the design of Takagi-Sugeno regulator is derived from optimal control. The feedback gains are determined by linear quadratic instruction. This Technique is applied on test system. Important issues of transient stability and design are remarked.

This paper dealt with the optimal distribution network planning (DNP) under loads growth condition where the Particle Swarm Optimization with Constriction Factor (PSO-CF) was considered. This paper aimed at ensuring that the consumers' load demands which always increase with time can be satisfied in an optimum way by the distribution network reconfiguration (DNR). The planning problem was addressed as a mono-criterion one with reduced power losses cost objective. The radiality, voltages limits, and power balance constraints were taken into consideration in this study. So as to evaluate the active power losses, a load flow technique was carried out. The PSO-CF was tested on IEEE-10 bus. All simulation studies and results showed the algorithm efficiency and capability to fulfill good results.

The Flexible AC transmission System (FACTS) devices, such as, thyristor controlled series compensators (TCSC) may be used to enhance system performance by controlling the power flows in the network. It is important to limit the number of TCSCs and to locate optimally these devices in the power system because of their considerable costs. Firstly, we have applied optimization technique, namely, NSGA-II, to find out the optimal number of multi-devices of TCSC in order to improve the system loadabilty, to reduce the installation cost of these series FACTS and to minimize the real power losses. Secondly, we perform a contingency analysis procedure based on severity index (SIl) to identify and classify the most severe line contingencies. Then, we determine the optimal placement and parameter setting of TCSCs in stressed power system by using the above optimization approach to alleviate the line overloads. In this paper, the optimization problem consists to reduce TCSCs installation cost and to decrease total real power losses. To demonstrate the effectiveness of the proposed approach, IEEE 30-bus test system has been studied.

The rate of dissipation of transient energy is usually used as a tool to measure dynamic system damping. This paper applies and discusses the above control strategy for suppressing undesirable electromechanical oscillations in power system with a STATic synchronous COMpensator (STATCOM), static synchronous series compensator (SSSC) and unified power flow controller (UPFC). A single machine infinite bus power system was studied over a several disturbance. The obtained results show the effectiveness and robustness of these devices on power system stability.