Voltage and Frequency Control in a Hybrid Standalone Power System for Improved Energy Efficiency

This research investigates the control of voltage and frequency in hybrid standalone power systems to improve power efficiency, stability, and reliability. The study is structured around three core objectives: designing a control strategy for voltage and frequency regulation, analyzing the performance of different energy sources under varying load conditions, and evaluating the impact of Battery Energy Storage Systems (BESS) on overall system stability. A simulation-based approach with MATLAB/Simulink software was adopted to model and assess a hybrid system incorporating solar, wind, battery, and diesel energy sources. Results from the first objective indicate that systems lacking a control mechanism experienced significant voltage and frequency deviations up to ±15Volts and ±1.5Hz respectively primarily due to the intermittent nature of renewable sources and dynamic load demands. In contrast, the proposed control strategy successfully maintained voltage around 230Volts and frequency at 50Hz throughout the 24-hour cycle, confirming its effectiveness in stabilizing system output. The second objective evaluated various system configurations. Among them, the PV-Wind-BESS hybrid system demonstrated superior performance, achieving an efficiency of 91%, compared to 62% obtained from PV-only and 58% from Wind-only. The hybrid system also showed strong adaptability with solar energy dominating during peak daylight hours, wind providing supplementary input, and the battery system compensating during low-generation periods. Diesel generation was minimally engaged, further reducing fuel dependency. In the third objective, the role of BESS was critically examined. Its integration reduced frequency deviations to ±0.2Hz and voltage fluctuations to ±2Volts, highlighting its vital contribution to power quality. Furthermore, the intelligently managed control algorithm enabled seamless switching, ensuring continuous power supply and 100% operational efficiency without load shedding. These findings confirm that the optimal combination of hybrid renewable sources with BESS significantly enhances energy efficiency and power quality, making such systems ideal for deployment in off-grid or remote regions with limited access to centralized electricity. The research supports the advancement of intelligently controlled hybrid systems as a sustainable and reliable solution for modern energy needs.