The disclosure provides for systems and methods for controlling fluid flow into a power generation section of a tool string. In one aspect, multiple flow kits are fluidly coupled with a turbine, and flow of fluid into the turbine is regulated by selectively opening valves coupled with the flow kits. In another aspect, a valve is fluidly coupled with the turbine, and flow of fluid through the valve and into the turbine is regulated by opening, partially opening, closing, or partially closing the valve in response to measured operational parameter data.