A Strategy Based Adaptive Voltage Controller and Optimal load Current Observer for Three-Phase Inverter in Stand-Alone Distributed Generation Systems
Keywords:
Adaptive control, distributed generation (DG), distributed generation system (DGS), load current observer, stand-alone, three-phase inverter and voltage controlAbstract
This paper proposes an adaptive control method of three-phase inverters for stand-alone distributed generation
systems (DGSs) with and without controller. The proposed voltage controller includes two control terms: an adaptive
compensating term and a stabilizing term. The adaptive compensating control term is constructed to avoid directly
calculating the time derivatives of state variables. Meanwhile, the stabilizing control term is designed to asymptotically
stabilize the error dynamics of the system. Also, a fourth-order optimal load current observer is proposed to reduce the
number of current sensors and enhance the system reliability and cost effectiveness. The stability of the proposed voltage
controller and the proposed load current observer is fully proven by using Lyapunov theory. The proposed control system
can establish good voltage regulation such as fast dynamic response, small steady-state error, and low total harmonic
distortion under sudden load change.
