Easiest solution is to write UDF (user defined function) and apply it to your inlet instead of [constant] you have next to value. It's quite easy code if you want to have discrete values (example here: https://www.cfd-online.com/Forums/fluent-udf/82953-how-do-i-create-time-dependent-flows-udf.html), it gets a bit more complicated programming-wise if you want to make some continuous function of velocity (for example velocities throughout a day or year).

I've seen approach that instead of making time-dependant calculations (time and power consuming) you may use statistical approach, calculate most common directions from which wind flows and most common speeds from those directions and then try calculation with fixed, averaged value. It obviously doesn't quite represent what you will need but gives relatively fast and way cheaper approximation (with overestimating power output).

If you need some more help on implementing your UDF I can make you some step-by-step with tasks I'm currently calculating.

Kacper Kuta thank you, the givin UDF is for specific range of velocity. i want to vary inlet velocity with timesteps, contineously. Could you help me, how to write it?

What exactly don't you know? I'm not really any fluent with programming, but I guess that fairly common problem may be referring to a time in your code. While I'm not sure if it is completely stable solution you can get reference to time from system date reference (as in this example: https://archive.sap.com/discussions/thread/1923430). With constructing UDF you can also refer to Ansys UDF manual, I rarely have to change their example code.