Model predictive control of consensus-based energy management system for DC microgrid

The increasing deployment and exploitation of distributed renewable energy source (DRES) units and battery energy storage systems (BESS) in DC microgrids lead to a promising research field currently. Individual DRES and BESS controllers can operate as grid-forming (GFM) or grid-feeding (GFE) units independently, depending on the microgrid operational requirements. In standalone mode, at least one controller should operate as a GFM unit. In grid-connected mode, all the controllers may operate as GFE units. This article proposes a consensus-based energy management system based upon Model Predictive Control (MPC) for DRES and BESS individual controllers to operate in both configurations (GFM or GFE). Energy management system determines the mode of power flow based on the amount of generated power, load power, solar irradiance, wind speed, rated power of every DG, and state of charge (SOC) of BESS. Based on selection of power flow mode, the role of DRES and BESS individual controllers to operate as GFM or GFE units, is decided. MPC hybrid cost function with auto-tuning weighing factors will enable DRES and BESS converters to switch between GFM and GFE. In this paper, a single hybrid cost function has been proposed for both GFM and GFE. The performance of the proposed energy management system has been validated on an EU low voltage benchmark DC microgrid by MATLAB/SIMULINK simulation and also compared with Proportional Integral (PI) & Sliding Mode Control (SMC) technique. It has been noted that as compared to PI & SMC, MPC technique exhibits settling time of less than 1µsec and 5% overshoot

Understanding impulse purchased in facebook commerce-does big five matter?

The purpose of this research is to examine the effect of Big Five Model (BFM), the urge to purchase (UP) and urgency (UR) on impulse purchase (IP) in Facebook commerce (F-commerce), with the F-commerce purchase as control variable. So, the research purpose is explanatory as there is an existing model. Probability sampling technique was used in our research and data collection was done through Questionnaires. The sample size was 500 university students of Karachi. So, questionnaires are filled by the students of the different Universities of Karachi. The determination of the study was to classify the relationship of an impulse purchase in Face book commerce and the big five personality traits. In this research we are using correlation research design. Exploration of data was done through PLS (SEM) by performing reliability test, factor analysis and regression analysis test. The study presented that BFM, UP, UR and F-commerce purchase are important predictors of the F-commerce IP. UP is subjective by BFM and UR. BFM has a significant positive relationship with UR. The study confirms that consumer’s personality has great impact towards online buying the really most important factor in order to grab the consumer’s positive attitude towards online buying. In future researchers we can add moderating variables like age, gender and income in the same framework

Understanding impulse purchased in facebook commerce-does big five matter?

The purpose of this research is to examine the effect of Big Five Model (BFM), the urge to purchase (UP) and urgency (UR) on impulse purchase (IP) in Facebook commerce (F-commerce), with the F-commerce purchase as control variable. So, the research purpose is explanatory as there is an existing model. Probability sampling technique was used in our research and data collection was done through Questionnaires. The sample size was 500 university students of Karachi. So, questionnaires are filled by the students of the different Universities of Karachi. The determination of the study was to classify the relationship of an impulse purchase in Face book commerce and the big five personality traits. In this research we are using correlation research design. Exploration of data was done through PLS (SEM) by performing reliability test, factor analysis and regression analysis test. The study presented that BFM, UP, UR and F-commerce purchase are important predictors of the F-commerce IP. UP is subjective by BFM and UR. BFM has a significant positive relationship with UR. The study confirms that consumer’s personality has great impact towards online buying the really most important factor in order to grab the consumer’s positive attitude towards online buying. In future researchers we can add moderating variables like age, gender and income in the same framework

Analysis of Wind Energy Potential and Optimum Wind Blade Design for Jamshoro Wind Corridor

Pakistan is facing energy crisis since last decade. This crisis can be effectively handled by utilizing alternative energy resources. Pakistan has a huge wind energy potential of about 50,000MW. The contribution of costal area of Sindh, Pakistan in the total wind energy potential is about 43000MW. The Jamshoro wind corridor has the highest wind potential of all coastal areas of Sindh. In this paper a wind blade design has been developed and optimized for Jamshoro wind corridor. The theoretical blade design include the airfoil selection, appropriate chord length selection and optimization of twist angle. The designed blade has been analyzed using Q-blade. Considering the Jamshorowind conditions, blade of around 43 meters have been designed and optimized theoretically. Then the theoretical design is also been checked and verified in Q-blade. Theoretical optimization includes using different combinations of NACA profiles and using exhaustive iterative method to get optimized twist angle. This ensures the design with maximum power output with respect to wind speed of Jamshoro. For low wind speeds, theoretical results and simulated results in Q-blade were almost same but for high wind speeds, results were significantly different due to limitation of iterations in theoretical desig

Finite Control Set Model Predictive Control for Parallel Connected Online UPS System under Unbalanced and Nonlinear Loads

In this paper, the finite control set model predictive control (FCS⁻MPC) technique-based controller is proposed for the inverter of the uninterrupted power supply (UPS) system. The proposed controller uses the mathematical model of the system to forecast the response of voltage for each possible switching state for every sampling instant. Following this, the cost function was used to determine the switching state, applied to the next sampling instant. First, the proposed control strategy was implemented for the single inverter of the UPS system. Finally, the droop control strategy was implemented for parallel inverters to guarantee actual power sharing among a multiple-parallel UPS system. To validate the performance of the proposed controller under steady-state conditions and dynamic-transient conditions, extensive simulations were conducted using MATLAB/Simulink. The proposed work shows a low computational burden, good steady state performance, fast transient response, and robust results against parameter disturbances as compared to linear control. The simulation results showed that total harmonic distortion (THD) for the linear load was 0.9% and THD for the nonlinear load was 1.42%

Model predictive control of consensus-based energy management system for DC microgrid.

The increasing deployment and exploitation of distributed renewable energy source (DRES) units and battery energy storage systems (BESS) in DC microgrids lead to a promising research field currently. Individual DRES and BESS controllers can operate as grid-forming (GFM) or grid-feeding (GFE) units independently, depending on the microgrid operational requirements. In standalone mode, at least one controller should operate as a GFM unit. In grid-connected mode, all the controllers may operate as GFE units. This article proposes a consensus-based energy management system based upon Model Predictive Control (MPC) for DRES and BESS individual controllers to operate in both configurations (GFM or GFE). Energy management system determines the mode of power flow based on the amount of generated power, load power, solar irradiance, wind speed, rated power of every DG, and state of charge (SOC) of BESS. Based on selection of power flow mode, the role of DRES and BESS individual controllers to operate as GFM or GFE units, is decided. MPC hybrid cost function with auto-tuning weighing factors will enable DRES and BESS converters to switch between GFM and GFE. In this paper, a single hybrid cost function has been proposed for both GFM and GFE. The performance of the proposed energy management system has been validated on an EU low voltage benchmark DC microgrid by MATLAB/SIMULINK simulation and also compared with Proportional Integral (PI) & Sliding Mode Control (SMC) technique. It has been noted that as compared to PI & SMC, MPC technique exhibits settling time of less than 1μsec and 5% overshoot

Techno-Economic Analysis of Hybrid Renewable Energy-Based Electricity Supply to Gwadar, Pakistan

Gwadar is essential to Pakistan’s financial stability. Being the third deep-water port in Pakistan, it plays a significant role in trade between the Gulf States, Africa, UAE, and CARs. The load shedding of 12–16 h in Gwadar is the most concerning issue due to the non-availability of a utility grid, which is why the Pakistan imports 70 MW of electricity from Iran to fulfill Gwadar’s electricity needs. Gwadar has renewable energy resources that can be utilized for electricity generation. However, wind and solar systems were only installed for limited residential areas. Considering this scenario, a technological and economic analysis was performed using the Hybrid Optimization Model for Multiple Energy Resources (HOMER) software. Three models were considered in this study. Model 1 consisted of photovoltaic (PV) cells, wind turbines, converters, and batteries. Model 2 consisted of PV cells, wind turbines, converters, and a grid. Model 3 consisted of PV cells, wind turbines, converters, and diesel generators. The annual energy generated by Model 1, Model 2, and Model 3 was respectively 57.37 GWh, 81.5 GWh, and 30.4 GWh. The Levelized Cost of Electricity (LCOE) for Model 1, Model 2, and Model 3 was respectively USD 0.401/kWh, USD 0.0347/kWh, and USD 0.184/kWh. The simple payback period of Model 1 was 6.70 years, the simple payback period of Model 2 was 7.77 years and the simple payback period of Model 3 was 4.98 years. Because Model 3 had the lowest Net Present Cost NPC, its payback period was also less than those of the other two. However, Model 2 had the lowest LCOE and its renewable fraction was 73.3%. These facts indicate that Model 2 is the optimal solution

The Effect of Neuropathic Pain on Psychological Well-Being of An Individual

This comprehensive study delves into the intricate relationship between neuropathic pain and psychological well-being among individuals while exploring the multifaceted influences of pain severity, gender, socio-economic class, and potential gender-based disparities. Employing a cross-sectional design, data were meticulously gathered from a sample of 110 participants within a medical facility. To assess neuropathic pain and psychological well-being, the study thoughtfully employed self-report measures, notably the DN4 Questionnaire for pain assessment and the Satisfaction with Life Scale for evaluating psychological well-being. The findings of this study unveiled a robust and statistically significant negative correlation between neuropathic pain and psychological well-being (r = -0.87, p = 0.02). This compelling correlation indicates that as the severity of neuropathic pain escalates, psychological well-being tends to markedly diminish. This relationship was further corroborated through linear regression analysis, demonstrating that for each incremental unit increase in neuropathic pain, there is a corresponding decrease of 0.87 units in psychological well-being (p = 0.001). Furthermore, this study unearthed noteworthy negative correlations between neuropathic pain and distinct domains of life, encompassing general activity, mood, normal work, relationships, sleep and enjoyment in life. These correlations illuminate that as the severity of neuropathic pain intensifies, individuals encounter impediments in various facets of their lives, including their daily activities, emotional states, work performance, social interactions, sleep quality, and overall life satisfaction. Notably, the socio-economic class emerged as a salient factor influencing well-being, with individuals in the middle class exhibiting significantly higher well-being scores when compared to their counterparts in the lower socioeconomic class (F = 5.770, p = 0.004). Intriguingly, gender did not wield a substantial impact on either well-being or pain levels in this study's context. The profound implications of these findings underscore the imperative necessity for the development and implementation of comprehensive pain management strategies, as well as robust psychosocial support systems tailored to individuals grappling with neuropathic pain. Future avenues of research should consider adopting longitudinal study designs to gain insights into the evolution of these relationships over time and should also explore nuanced cultural and gender-related factors that might further elucidate the complex interplay between pain experiences and psychological well-being

Do Financial Crises Matter for Nonlinear Exchange Rate and Stock Market Cointegration? A Heterogeneous Nonlinear Panel Data Model with PMG Approach

The existing literature has explained the causality flow from the exchange rates toward the stock market without explaining the role of the economic crisis in effecting this nexus. This study examines the role of the financial crisis in affecting the nonlinear causality flowing from the exchange rates toward the stock market indexes of the ASEAN-5 region. The precrisis, postcrisis, and overall sample duration comprised 365, 650, and 1085 observations over the periods from January 2002 to January 2008, January 2010 to January 2020, and January 2002 to January 2020, respectively. The results showed that the conventional symmetrical panel ARDL (PARDL) model was not able to formulate long-run cointegration between currency value fluctuations and stock market indexes for both regimes, i.e., the post recessionary and pre recessionary periods. However, asymmetrical cointegration was established between the currency values and stock market indexes for the pre recessionary period and the overall sampling time frame by utilizing the panel-based NARDL framework (PNARDL). The study suggests practical implications for the exporters and importers to consider the regime as well as both the negative and positive shocks in the international dollar values while making forward contractual agreements

A Composite Exponential Reaching Law Based SMC with Rotating Sliding Surface Selection Mechanism for Two Level Three Phase VSI in Vehicle to Load Applications

Voltage source inverters (VSIs) are an integral part of electrical vehicles (EVs) to enhance the reliability of the supply power to critical loads in vehicle to load (V2L) applications. The inherent properties of sliding mode control (SMC) makes it one of the best available options to achieve the desired voltage quality under variable load conditions. The intrinsic characteristic of robustness associated with SMC is generally achieved at the cost of unwanted chattering along the sliding surface. To manage this compromise better, optimal selection of sliding surface coefficient is applied with the proposed composite exponential reaching law (C-ERL). The novelty of the proposed C-ERL is associated with the intelligent mix of the exponential, power, and difference functions blended with the rotating sliding surface selection (RSS) technique for three phase two level VSI. Moreover, the proposed reaching law along with the power rate exponential reaching law (PRERL), enhanced exponential reaching law (EERL), and repetitive reaching law (RRL) were implemented on two level three phase VSI under variable load conditions. A comparative analysis strongly advocates the authenticity and effectiveness of the proposed reaching law in achieving a well-regulated output voltage with a high level of robustness, reduced chattering, and low %THD