Lets say you decide to install an inverter on site ... cost around R1200 would get you a small inline ups ... from what I understand is in bypass until the power switches off ... it only has a smooth clean power when in UPS mode (power off)

You can also use an inverter to do a similar function ... inverters have an appliance and UPS setting ... which basically allows for a wider voltage tolerance.

Then you get an online UPS ... these things are not cheap ... the fist one I ever installed about 20 years ago cost R25000.00 and is still working to this day.

An online UPS has no switching at all ... it runs in clean power mode all the time regardless of the voltage input.