2 research outputs found
Impact of Forecast Time-Step on PV Production Accuracy Using Machine Learning for Micro-Grid Efficiency
No full textEfficient energy management solutions are becoming more important with emergence of micro-grids that include photovoltaic generation & storage. Their prediction of energy output over the near to long term is an important part of their work. An essential parameter influencing the forecast's accuracy, optimum control time discretisation, efficiency, and computing load is the forecast time-step. This trade-off is measured by putting four machine learning (ML) forecast methods through their paces on two different sites, with time-steps ranging from 2 to 60 minutes as well as horizons from 10 minutes to 6 hours. The methods are evaluated on both horizontal and tilted global irradiance charts, depending on the availability of data. All of the methods show comparable findings, which show that for predictions less than an hour and between one and six hours, the error measure may be decreased by up to 1.9% every minute on the time-step, and by up to 2.8% every ten minutes. Additionally, it is demonstrated that for short-term horizons, it could be beneficial towards make high-resolution forecasts & then average results at time-step required by energy control scheme
Time-Frequency Analysis of Strong Ground Motions from the Mw 6.8 1991 Uttarkashi Earthquake
No full textThe stress build-up along the plate boundary of the Indian and Asian plates is a source of major destructive earthquakes in the state of Uttarakhand. The high seismic hazard in the region has led the Indian Standard Code 1893:2016 to place the entire state of Uttarakhand in seismic zone IV and V, corresponding to seismic intensity levels of severe and very severe, respectively. On 20th October 1991, a strong earthquake having a moment magnitude Mw 6.8, occurred along the Main Central Thrust in the Uttarkashi and Garhwal regions. Field observations indicated that the maximum damage intensity corresponded to a level of IX as per the modified Mercalli Intensity scale. Reconnaissance studies performed in the aftermath of the earthquake indicate that the high lateral forces generated by the horizontal shaking associated with the strong ground motions caused severe destruction of stone masonry and concrete block structures prevalent in the region. Strong ground motions from the 1991 Uttarkashi earthquake are obtained from 13 stations with hypo-central distances varying from 22 to 155 km. The 26 horizontal waveforms are analyzed and their key characteristics, such as Peak Ground Acceleration (PGA), Peak Ground Velocity (PGV), Arias Intensity (AI), and Predominant Period (Tp) and significant duration are tabulated. The frequency content is analyzed using fast Fourier transforms and the time-frequency analyses are performed using continuous wavelet transforms. The results indicate that the arrival of high-amplitude waves with high frequencies corresponding to the resonant frequency range of low-rise structures at several sites corresponds to observed enormous damage to the structures. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd
