An AC Voltage Sensor-less Control Strategy for Ocean Ship Photovoltaic Grid-connected Inverter with LCL Filter

In the traditional controlling of PV inverter with LCL filter, an extra sensor is needed to detect the voltage of PoC (point of connection) and to restrain the inherent resonance in LCL filters, which increases the control costs and reduces the system reliability. This paper proposes an AC Voltage Sensor-less control strategy for ocean ship photovoltaic grid-connected inverter with LCL filter. Based on the droop control principle, the instantaneous reference voltage is obtained from active and reactive power. Besides, virtual impedance is added to suppress harmonic, which improves the quality of grid-connected current and the accuracy of power control. Simulation results show the feasibility and effectiveness of the proposed control strategy.