1 Department of Energy Technology, The Faculty of Engineering and Science, Aalborg University, VBN2 Power Electronic Systems, The Faculty of Engineering and Science, Aalborg University, VBN3 The Faculty of Engineering and Science, Aalborg University, VBN4 Ferdowsi University of Mashhad5 Islamic Azad University6 Ferdowsi University of Mashhad7 Islamic Azad University
Control of three-phase power converters in the synchronous reference frame is now a mature and well developed research topic. However, for single-phase converters, it is not as well-established as three-phase applications. This paper deals with the design of a synchronous reference frame multi-loop control strategy for single phase inverter-based islanded distributed generation (DG) systems. The proposed controller uses a synchronous reference frame PI (SRFPI) controller to regulate the instantaneous output voltage, a capacitor current shaping loop in the stationary reference frame to provide active damping and improve both transient and steady-state performances, a voltage decoupling feedforward to improve the system robustness, and a multi-resonant harmonic compensator to prevent low-order load current harmonics to distort the inverter output voltage. Since, the voltage loop works in the synchronous reference frame, it is not straightforward to fine-tune the control parameters and evaluate the stability of the whole closed loop system. To overcome this problem, the stationary reference frame equivalent of the voltage loop is derived. Then, a step-by-step systematic design procedure based on a frequency response approach is presented. Finally, the theoretical achievements are supported by experimental results.
I E E E Transactions on Industrial Electronics, 2014, Vol 61, Issue 1, p. 258-269