Electric Spring for Voltage and Power Stability and Power Factor Correction

The increasing integration of renewable energy sources introduces challenges such as voltage instability and degraded power quality in modern power systems. This paper proposes an improved Electric Spring (ES) control scheme to enhance voltage stability, power balance, and power factor in renewable energy-based microgrids. Unlike conventional ES, which provides only reactive power compensation, the proposed method enables both active and reactive power control using a single-phase inverter with a d–q control strategy. The controller regulates the supply voltage to a constant reference value while ensuring near unity power factor by aligning input current with the supply voltage. The performance of the system is analyzed under both overvoltage and undervoltage conditions using MATLAB/Simulink simulations and Hardware-in-the-Loop validation. Results demonstrate that the improved ES effectively stabilizes voltage, maintains power for critical loads, and significantly improves overall power quality compared to conventional methods, making it a promising solution for future smart grid applications.

Keywords: Electric Spring (ES), voltage stability, power factor correction (PFC), renewable energy systems, microgrid, demand side management (DSM), active and reactive power compensation, d–q control strategy, power quality improvement, and single-phase inverter.