I installed 35 kW solar Panel with 29 kW inverter system. Do I need to install Grid Protection unit?

A: No, as inverter less than 30 kVA.

Can I use Grid Protection to do export limiting

A: NO. Grid protection and Export control is two different matters.  For export control , you can simply use smart meter from inverter manufacturer to achieve that.

If I limit solar export below 30 kW to the grid, do I still need grid protection ?

A: Yes. As stated in AS4777, As long as your inverters size are bigger than 30 kVA,  you will need to install grid protection.  Besides, you still need to apply to grid for installing bigger system whether you do export control or not.

DNSP doesn’t ask for Grid protection. Do I need to install grid protection

A: Yes. Install grid protection is a compulsory requirement in AS4777. DNSP may have further requirement on the top of that.