The article describes results of experimental research concerning a prototypical hydrodynamic clutch controlled via changes in flow rates of the working fluid. The aim of the research was to collect experimental data to confirm the practical possibility of using such a control method of the hydrodynamic clutch and to compare this with other currently used. A change in flow rate of the working fluid was obtained by increasing distance between rotors. The experimental research was conducted on a test rig built specifically for this purpose. Based on the research, the influence of the clutch filling level, the direction of rotation and the temperature of the working fluid on the clutch torque were determined. The experimental research shows that the transferred torque is significantly influenced by the width of the gap between rotors, the rotational speed of the input shaft, the clutch’s filling degree and the temperature of the working fluid. Thus, these values may be used to control the torque transferred by the hydrodynamic clutch. The temperature of the working fluid is not recommended as a control value due to the fact that it is dependent on the working conditions of the hydrodynamic clutch. On the basis of the test results, it was proven that hydrodynamic clutches controlled by increasing distance between rotors, for example can be successfully used in drive systems of wind farms.