In this paper, a grid connected microgrid with multiple inverter-based distributed generators (DGs) is considered. DG in FFC mode regulates the microgrid as a controllable load from the utility point of view as long as its output is within the capacity limit. The transition mode causes a change in frequency of microgrid due to the loss of power transferred between main grid and microgrid. Frequ...

The leading edges of the main rotor blades of a Wessex helicopter were artificially roughened to simulate light to moderate erosion of unprotected light alloy blades. Pitch link loads were measured in forward flight for various spanwise extents of leading-edge roughness, and the values of forward speed at which a pre-set limit of oscillatory pitch link load was reached were determined. This lim...

In recent years, voltage limit violation and power system load-generation imbalance, i.e., line loading limit violation have been responsible for several incidents of major network collapses leading to partial or even complete blackouts. Alleviation of line overloads is the suitable corrective action in this regard. The control action strategies to limit the line loading to the security limits ...

This paper will discuss about an active power generator scheduling method in order to increase the limit level of steady state systems. Some power generator optimization methods such as Langrange, PLN (Indonesian electricity company) Operation, and the proposed Z-Thevenin-based method will be studied and compared in respect of their steady state aspects. A method proposed in this paper is built...

Compression tests carried out on aluminium specimens showed that when the die was rotated the compression load dropped. A slab method is employed to examine this process. The load reduction is explained by the deviation of friction vector due to the relative circumferential movement between the die and the material. This mechanism is incorporated into a theoretical model and an expression is de...

The collapse state of a rigid plastic material with the linearized Mises yield condition is computed. We use an infeasible point variant of the dual aane scaling algorithm for linear programming which is extremely eecient for this large sparse and ill conditioned problem. For a classical test problem we obtain better results than previously, both for the limit load and for the collapse elds, th...

The non-linear programming theory along with active set algorithm is employed to solve the objective function of quadratic type problem in soil mechanics under plain strain and two dimensional loading conditions. Combination of lower bound limit analysis and finite element method leads to an appropriate procedure for determining the collapse load of the system. In this combined method, a linear...

A multi-objective optimization method for the structural design of horizontal-axis wind turbine (HAWT) blades is presented. The main goal is to minimize the weight and cost of the blade which uses glass fiber reinforced plastic (GFRP) coupled with carbon fiber reinforced plastic (CFRP) materials. The number and the location of layers in the spar cap, the width of the spar cap and the position o...