Photovoltaic inverter power limit control

How to provide voltage support in PV inverter?

To provide voltage support at the PCC, reactive power is injected into the grid under fault conditions as per the specified grid codes. As previously discussed, the simultaneous injection of peak active power from PVs and reactive power into the grid for voltage support can trigger the over current protection mechanism in PV inverter.

Can a single-stage photovoltaic inverter system control grid connected power?

This article proposes a combined control strategy of maximum power tracking (MPPT) and limited power control based on auto-disturbance rejection (ADRC) technology for single-stage photovoltaic inverter systems, achieving flexible control of grid connected power generation in single-stage photovoltaic inverter systems.

What is the use of bus voltage in a photovoltaic inverter?

The increase in bus voltage is used as the control signal of the PV output current to reduce the photovoltaic output current, such that the PV output power is reduced from 3000 W to the inverter power limit value of 1500 W, which meets the requirements of the inverter output power limit.

How does a photovoltaic system work in power limit mode?

The PV works in power limit mode, and the output current of the PV is reduced by controlling the boost converter. According to the photovoltaic I–V characteristic curve, the output voltage of the PV increases as a result and moves further away from the maximum power point.

What is over current protection mechanism in PV inverter?

As previously discussed, the simultaneous injection of peak active power from PVs and reactive power into the grid for voltage support can trigger the over current protection mechanism in PV inverter. The triggering of over current protection will lead to disconnection of inverter from the grid which is unfavourable during LVRT period.

Does a two-phase and three-phase dip in grid voltage limit inverter current?

The results under two-phase and three-phase dip in the grid voltage shows that the proposed control strategy injects maximum reactive and active power and limits the inverter current by quickly activating the APC control loop during fault-ride-through period.