The question is related to a broad research area. Please find the link below to narrow down your topic of interest. Later, you can gather information from the latest research papers for starting your project. All the best!
Smart Grid includes many aspects like communication, control, etc. So it actually depends on your major. However, the most important for you to know is to search for the recent issues or problems related to your major in smart grid and choose one to try to solve considering the main aims of developing smart grid is to optimize the utilization of consumption and production of energy
there are many of interdisciplinary nature in Smart Grid development and depending on your major you can select whichever is suitable to you. For instance, if your major is in Communication, you may look at the type of communication network suitable for particular applications areas of Smart Grids, such as smart metering. this is just one example, and you can add more and more examples depending on your area of interest.