A novel review on optimization techniques used in wind farm modelling

This paper presents the supercapacitors (SC) behavior characterization using the temperature combined to the frequency of the dc-current ripples called here electro-thermal stress. To characterize the evolution of the resistance and the capacitance of the SC, the authors have evaluated the impact of the state of charge (SoC), the number of cycles, the temperature, and the temperature combined to the frequency of the dc-current ripples. This approach enables to show the variations of the SCs resistance and capacitance according to the real constraints imposed by application. The main contribution of this paper is focused on the SCs aging characterization and modeling, using the electro-thermal stress. The experimental tests of the SC characterization and modeling are based on the charge/discharge operations, using the fluctuating and no-fluctuating dc-current waveforms. The proposed model takes into account the variations of the resistance and capacitance of the SC according to the temperature, the frequency of dc-current ripples and the SoC. The terminal voltage of the SC obtained from the proposed model is close to the experimental result, with an error about 1%. So, the proposed model is satisfactory to predict the SCs behavior during the charge/discharge operations using a fluctuating dc-current combined to a variable temperature and SoC.

Supercapacitors Characterization and Modeling Using Combined Electro-Thermal Stress Approach Batteries

https://upcommons.upc.edu/bitstream/handle/2117/76976/Paper_SSR_T2WT_Elsevier_FM_Final.pdf?sequence=1

Modeling and Control of Type-2 Wind Turbines for Sub-Synchronous Resonance Damping

Practicable life extension of engineering systems would be a remarkable application of prognostics. Although considerable research has been devoted to developing prognostics algorithms, rather less attention has been paid to post-prognostic issues such as maintenance decision making. This research investigates the use of prognostic data to mobilize the potential residual life. In this respect, a multi-objective optimization model is presented for a typical power generation unit. This model proves the ability of prognostic models to balance between power generation and life extension. The results of the optimization models quantitatively indicated that maximizing the service life of bearings requires lower shaft speed and longer maintenance time.

Operation and maintenance decision-making using prognostic information

In this paper, three different impedance source inverters: Z-source inverter, EZ- source inverter, TZ-Source for wind energy conversion system (WECS) were investigated. Total output power and THD of each of these systems are calculated. The proposed system can boost the output voltage effectively when the low output voltage of the generator is available at low wind speed. This system has higher performance, less components, increased efficiency and reduced cost. These features make the proposed TZSI based system suitable for the wind conversion systems. MATLAB simulink model for wind generator system is developed and simulation studies are successfully performed. The simulation is done using MATLAB and the simulation results are presented. This comparison shows that the TZ-source inverter is very promising for wind energy conversion system.

/pdf/comparison-of-z-source-ez-source-and-tz-source-inverter-2lceq5zuv6.pdf

Giddani Osman Addlan Supervisor

Papers

Dynamic Influences of Wind Power on the Power System