This paper focuses on developing an approach to steady-state power flow control of flexible ac transmission systems (FACTS) device-equipped power systems. Based on a power-injection model of FACTS devices and an optimal power flow model, a novel versatile power flow control approach is formulated, which is capable of implementing power flow control incorporating any FACTS device flexibly. Different from existing FACTS device control approaches, the active and (or) reactive power injections are taken as independent control variables. Therefore, using this method, Jacobian matrix need not be changed, although various FACTS devices possess different physical models and different control parameters. Furthermore, it enables the integration of FACTS devices into the existing power system analysis and control programs efficiently. Physical limits of the FACTS devices are also considered in the model. Numerical results on a reduced practical system and a 1500-bus practical system with various FACTS devices are presented to illustrate the vigorousness of the proposed approach.

A method of pre-feedback to formulate the generalised forced Hamiltonian system model for speed governor control systems is proposed. Furthermore, passivation controllers are designed based on the scheme of Hamiltonian structure for single machine infinite bus and multimachine power systems. In particular, in the case of multimachine systems, all the variables in the control law are only relevant to the state variables of the local generator, which means that a decentralised controller is achieved. Simulation results of a four-machine system show that the controller can enhance power system transient stability.

This loiter first derivcs Hamiltoniam cquation fora power system with cxcitation control A modified energy-based Lyapunov function is thon presented for fast tcabsuebt stability analysis of con trolled power systems.

China is a developing country. With the move towards deregulation and opening markets,there have been many changes in the industrial andtechnical sector, especially in the power industry.The changes penetrate into generation, transmission,and distribution systems. With developmentof the Three Gorges project started in the 1990s,many studies and test projects have been carriedout to determine the type of transmission lines, automationdevices, etc. The progress associatedwith the Three Gorges power system, compactlines, and distribution automation may be summarizedas follows.

To tackle the obstacle of applying passivity-based control (PBC) into power systems, an affine non-linear system widely existing in power systems is formulated as a standard Hamiltonian system using a pre-feedbaek method. The port controlled Hamiltonian with dissipation (PCHD) model of TCSC is then established corresponding with a revised Hamiltanian function. Furthermore, employing the modified Hamiltonian function directly as the storage function, a non-linear adaptive L2 gain control method is proposed to solve the problem of L2 gain disturbance attenuation for this Hamiltonian system with parametric perturbations. Finally, simulation results are presented to verify the validity of the proposed controller.

A novel methodology is proposed to evaluate the available transfer capability (ATC) of prescribed interfaces in connected power networks. With respect to the major uncertain factors affecting the ATC value, a realistic stochastic model is formulated in which availability of generators and circuits are considered as random variables following binomial distributions. With reasonable assumptions, fluctuations of loads are taken into consideration as normally distributed variables. To deal with the complex problem formulated with both discrete and continuous variables involved efficiently, a hybrid stochastic approach which takes advantage of both two-stage stochastic programming with recourse and chance constrained programming is proposed. The necessity of considering the impact of uncertainties on ATC assessment is demonstrated clearly by using the IEEE 118-node standard. Numerical results also illustrate the capability and efficiency of the proposed methodology.