High-speed real-time dynamic economic load dispatch

A large amount of renewable energy penetration may cause a serious problem in load dispatch in the future power system, where the amount of controllable generators will decrease while disturbances increase. Therefore, a new economic load dispatch (ELD) method is required in order to make the best use of the ramp-rate capability of existing generators to cope with the disturbances caused by loads as well as by renewable energy generations. This paper proposes a new dynamic ELD method to meet the general requirements for real-time use in a future power system, where load following capability is critically limited. The method is also satisfactory from an economical point of view, and is suitable for high-speed online application due to fast and steady computation time. The proposed method has been successfully tested on several systems supplying a typical morning to noon demand profile

Multi-load level reactive power planning considering slow and fast VAR devices by means of particle swarm optimisation

The problem of optimal allocation of fast and slow reactive power VAR devices under different load levels is addressed. These devices are supposed to be utilised to maintain system security in normal and contingency states, where corrective and preventive controls are implemented for the contingency cases. Load shedding and fast VAR devices are used in the corrective state in order to restore the system stability very quickly, even though they are highly expensive, whereas cheap slow VAR devices can be used in the preventive state to obtain the desired security level. The main objective is to establish a trade-off between economy and security by determining the optimal combination of fast and slow controls (load shedding, new slow and fast VAR devices). To meet the desired steady-state security limits, a variety of constraints have to be considered during the investigated transition states. The overall problem is formulated as a large-scale mixed-integer nonlinear programming problem. Particle swarm optimisation as an efficient method for solving such problems is applied to solve the problem. The proposed approach has been successfully tested on the IEEE-14 as well as IEEE-57 bus systems

Transient stability assessment as boundary value problem

This paper proposes a method for transient stability analysis for multi-machine electric power systems. Different from existing methods, a minimization problem with boundary values is formulated for obtaining critical conditions for transient stability, where a new numerical integration method is developed by modifying the trapezoidal formula to solve effectively the boundary value problem. The proposed method is to compute directly a trajectory on the stability boundary, which is referred to as critical trajectory in this paper. The critical trajectory to be obtained is the trajectory that starts from a point on a fault-on trajectory and reaches a critical point such as an Unstable Equilibrium Point (UEP), or more exactly, Controlling UEP (CUEP). The solution of the minimization problem provides the critical trajectory and the exact Critical Clearing Time (CCT) without major approximation

A coordinated heat and electricity dispatching model for Microgrid operation via PSO

2010 International Conference on Life System Modeling and Simulation, LSMS 2010 and the 2010 International Conference on Intelligent Computing for Sustainable Energy and Environment, ICSEE 2010, Wuxi, 17-20 September 20102010-2011 > Academic research: refereed > Publication in refereed journa

Sustainable Materials Science and Green Metallurgy (Sustainable Materials and Metallurgical Science & Engineering)

Sustainable Materials and Metallurgical Science & Engineerin