Measurement-Based Equivalent Model of Distribution Networks Considering Static and Dynamic Loads

Background: Since the distribution networks are passive until Distributed Generation (DG) is not being installed into them, the stability issues occur in the distribution system after the integration of DG. Methods: In order to assure the simplicity during the calculations, many approximations have been proposed for finding the system’s parameters i.e. Voltage, active and reactive powers and load angle, more efficiently and accurately. This research presents an algorithm for finding the Norton’s equivalent model of distribution system with DG, considering from receiving end. Norton’s model of distribution system can be determined either from its complete configuration or through an algorithm using system’s voltage and current profiles. The algorithm involves the determination of derivative of apparent power against the current (dS/dIL) of the system. Results: This work also verifies the accuracy of proposed algorithm according to the relative variations in the phase angle of system’s impedance. This research also considers the varying states of distribution system due to switching in and out of DG and therefore Norton’s model needs to be updated accordingly. Conclusion: The efficacy of the proposed algorithm is verified through MATLAB simulation results under two scenarios, (i) normal condition and (ii) faulty condition. During normal condition, the stability factor near to 1 and change in dS/dIL was near to 0 while during fault condition, the stability factor was higher than 1 and the value of dS/dIL was away from 0.

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New Research on the Use of Hardening Plastics for Aircraft Construction

Journal of the Royal Aeronautical Society ◽

10.1017/s0368393100104961 ◽

1940 ◽

Vol 44 (349) ◽

pp. 44-73

Author(s):

Wilhelm Kuech

Keyword(s):

Strength Properties ◽

Dynamic Loads ◽

Absorbed Energy ◽

Good Strength ◽

Different Temperatures ◽

Bonding Properties ◽

Static And Dynamic Loads ◽

Impact Bending ◽

New Research ◽

Laminated Materials

Laminated materials incorporating plastics seem to be especially well suited lor highly stressed aircraft components, by reason of their good strength properties. Paper, fabric and wood veneers treated with plastics on a phenolic basis were tested with regard to their strength, especially in bending, shear, absorbed energy in impact bending, notching strength and in their resistance against moisture. Further, the behaviour of compressed plastics was studied at different temperatures under static and dynamic loads. A part of the research was extended to pure phenol resin and to thermoplastics based on methacrylate and polyvinylchloride. The bonding properties of laminated compressed plastics were established. Concluding, some experiments relating to the practical manufacture of aeroplane components are communicated.

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Preliminary investigation of use of flexible folding wing tips for static and dynamic load alleviation

The Aeronautical Journal ◽

10.1017/aer.2016.108 ◽

2016 ◽

Vol 121 (1235) ◽

pp. 73-94 ◽

Cited By ~ 19

Author(s):

A. Castrichini ◽

V. Hodigere Siddaramaiah ◽

D.E. Calderon ◽

J.E. Cooper ◽

T. Wilson ◽

...

Keyword(s):

Aspect Ratio ◽

Preliminary Investigation ◽

Aircraft Design ◽

Dynamic Loads ◽

Induced Drag ◽

Aeroelastic Model ◽

Static And Dynamic Loads ◽

Folding Wing ◽

Wing Tips ◽

Wing Tip

ABSTRACTA recent consideration in aircraft design is the use of folding wing-tips with the aim of enabling higher aspect ratio aircraft with less induced drag while also meeting airport gate limitations. This study investigates the effect of exploiting folding wing-tips in flight as a device to reduce both static and dynamic loads. A representative civil jet aircraft aeroelastic model was used to explore the effect of introducing a wing-tip device, connected to the wings with an elastic hinge, on the load behaviour. For the dynamic cases, vertical discrete gusts and continuous turbulence were considered. The effects of hinge orientation, stiffness, damping and wing-tip weight on the static and dynamic response were investigated. It was found that significant reductions in both the static and dynamic loads were possible. For the case considered, a 25% increase in span using folding wing-tips resulted in almost no increase in loads.

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The Mechanical Properties Comparative Analysis for Socked and Non-Socketed Composite Pile

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1061-1062.748 ◽

2014 ◽

Vol 1061-1062 ◽

pp. 748-750

Author(s):

Heng Chen ◽

Ke Sheng Ma

Keyword(s):

Mechanical Properties ◽

Comparative Analysis ◽

Seismic Performance ◽

Dynamic Loads ◽

Vertical Load ◽

Interlayer Thickness ◽

Static Loads ◽

Soil Stress ◽

Composite Pile ◽

Static And Dynamic Loads

For socked and non-socketed piles in the different mechanical behavior under static and dynamic loads, the paper use ABAQUS to model, simulate the pile , the soil interlayer thickness between the bottom of the pile and bedrock are 2m, 4m under vertical load and Earthquake, cushion cap, pile and pile soil stress situation found non-socketed piles when the soil interlayer thickness within a certain range, the composite pile small subside under dynamic, static loads, the non-socketed piles can better take advantage of the pile soil has a good seismic performance in the earthquake.

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Manufacturing of Bellows Compensator by Pulsed-Magnetic Field Pressure

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1049.108 ◽

2022 ◽

Vol 1049 ◽

pp. 108-113

Author(s):

Nikolay Kurlaev ◽

Ahmed Soliman Mohamed Sherif ◽

Nikolay Ryngach

Keyword(s):

Relative Elongation ◽

Operating Time ◽

Dynamic Loads ◽

Pulse Field ◽

Magnetic Pulse ◽

System Operation ◽

Effective Protection ◽

Expansion Joints ◽

Static And Dynamic Loads ◽

Tubular Billet

Bellows are a cylindrical shell with a corrugated part, widely used in aviation engineering as a movable sealing element to balance pressure and temperature differences, which ensure continuous and accurate system operation. The use of bellows expansion joints provides reliable and effective protection of pipelines from static and dynamic loads arising from deformations and vibration. Welded-edge bellows are a popular choice for regulating and controlling fuel supply in aircraft devices. The ability of the compensator to perceive deformations is determined by its assigned operating time, which describes how many cycles, and with what amplitude, the bellows compensator perceives without damage. A method for stamping bellows from tubular billets by using magnetic-pulse field in rigid dies, including sequential shaping of corrugations by distributing the internal magnetic pressure with axial movement of the free end of a tubular billet, characterized in that the material of the tubular billet for shaping corrugations is selected in accordance with its relative elongation.

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