Voltage regulator

Control (management)

Voltage

Engineering

Biology

Voltage sag

Grid code

Computer science

Fault (geology)

Seismology

Grid

Controller (irrigation)

Geology

Low voltage ride through

AC power

Mathematics

Inverter

Agronomy

Voltage droop

Voltage controller

Artificial intelligence

Geometry

Power quality

Control theory (sociology)

Photovoltaic system

Electrical engineering

IEEE Transactions on Power Electronics

This article presents a dynamic voltage support (DVS) scheme for achieving low-voltage ride-through (LVRT) with a grid-connected photovoltaic (PV) inverter during the voltage sag fault. The DVS scheme is achieved by formulating an additional reactive active current control mode which is developed from a conventional reactive current control approach. This provides stable operation of the system and achieves higher effectiveness due to the lower <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">X</i> / <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">R</i> ratio at the point of common coupling in low-voltage networks. Further, the performance of the proposed controller is assessed by simulating a 4 kW system for voltage sag faults. Further, the proposed controller tested with the real-time simulations and experimental setup for voltage sag conditions. The results presented demonstrate that the active and reactive power is regulated in concordance with grid code requirements. The controller achieves LVRT within the time limits of grid standard during symmetrical faults, which makes it appropriate for fast transient events. This operates the PV system under its nominal capacity, avoiding unwanted grid disconnection events.

Dynamic Voltage Support for Low-Voltage Ride-Through Operation in Single-Phase Grid-Connected Photovoltaic Systems