Decoupled Power Control With Indepth Analysis of Single-Phase Electric Springs

• Published in: IEEE access Vol. 8; pp. 21866 - 21874
• Main Authors: Wang, Qingsong, Zuo, Wujian, Cheng, Ming, Deng, Fujin, Buja, Giuseppe
• Format: Journal Article
• Language: English
• Published: Piscataway IEEE 2020; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Algorithms; Closed loops; Control algorithms; Control theory; Decoupling; distributed generation; Electric potential; Electric spring; Emulators; energy storage; Heuristic algorithms; Inverters; Mathematical model; microgrid; Phase locked loops; Phase locked systems; Photovoltaic cells; Power control; Reactive power; renewable energy source; Springs; Springs (elastic); Voltage; Voltage control
• ISSN: 2169-3536; 2169-3536
• DOI: 10.1109/ACCESS.2020.2966677

Electric spring (ES) as a new effective way to solve the power quality issues caused by the uncertainty of wind and photovoltaic (PV) power, has the advantages of small volume, flexible configuration and low cost. Aiming at improving the dynamic responses of the existing power control for ES-2, a new control with in-depth analysis on the decoupling of the active and reactive powers is proposed in this paper. By introducing second order generalized integrator phase locked loop (SOGI-PLL) and fictitious-axis emulator (FAE) into the control algorithm, the virtual orthogonal voltage and current signals were constructed and the mathematic model of ES-2 in the dq axis synchronous rotating reference frame was established. Then, the control system consisting of three closed loops, namely active power loop, current loop and ES voltage loop, is arranged. Among the three loops, a damped proportional resonance (PR) controller is adopted in the ES voltage loop to ensure the accurate control of the output voltage of ES-2. Instead, traditional PI controllers are used for the current and power loops. Finally, the effectiveness of the proposed decoupled power control is validated by both simulation and experimental results.