Looking for time-series grid data set
Well, I think you will not find such information. However, you can mimic the reality. In conventional power systems, load dispatch centers perform economic dispatch/optimum power flow to distribute the expected load among the power plant. Based on this fact, 

1) You can take IEEE system, with per-unitized demand data.

2) Perform economic dispatch (or optimum power flow) to specify the power plants generation.

3) Now you have generation and load time series, you can run load flow for every sample to get (V,A) time series.

You may need the cost function of the generation units to perform the economic dispatch, there are many research papers where you can find such information for these generation units. See this and this for example. Moreover, You may need also demand time series, you may download it from here.

One more point, the previous information get closer to reality in countries where conventional power systems are still there. However, in restructured power systems, the energy market plays the main role in dispatching the generators.