Quant voltage regulators have the ability to return energy to the grid, which was not available before even in conventional double conversion regulators.
The return of energy to the grid is used when the consumer has solar cells to generate their own energy and sells its excess (green tariff). Again, due to the poor quality of the grid, sometimes solar inverters refuse to feed power (insufficient or excessive voltage in the grid), which causes voltage spikes in the grid due to the constant shutdowns/switching-on of the inverters.
Operation through QUANT gives the inverter the ability to always feed power into the grid with an accuracy of 220V, ie with the optimal mains voltage for the inverter. With this approach, the risk of damage to the inverter itself is sharply reduced, and it is usually much more expensive than a voltage regulator. The regulator will also protect the inverter because it considers the inverter as a consumer.