Might be worth looking at the CAN network as there is a lot of scope that can be covered, and can be intergrated with pre-exsisting software on a PC to give really good results. My friend got a scholarship based on the strength on the CAN network project that he did for his final year project. Well worth a look.
i think you want to make commercial market value product then try mcu based three phase sequence control with regulation , i am sure this will hit the market