Analysis and experimental validation for power calculation based on p-q theory in single-phase wireless-parallel inverters

Droop control method is the fundamental theory in wireless parallel operation. In droop method, the output active power and reactive power need to be calculated accurately for adjusting angular frequency and amplitude of inverter output voltage. So the accuracy and speed of power calculation is very important for the performance of parallel operation. Traditional calculation methods in single-phase inverter have a slow and oscillating transient response and could be easily impacted by disturbance and variation of load such as nonlinear and light load. In this paper, an optimized power calculation based on p-q theory is proposed and analyzed to solve the problem and improve dynamic performance. Finally, experimental results are presented from three single-phase 1kw inverters, validating the performance of the proposed method.

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