Abstract: The invention relates to an adjustable system for guiding the rotation of a shaft about a vertical axis, including skids, each of which is provided with a surface for forming a bearing with the shaft. For each skid, a shim is provided with a cam surface, the outline of which, in a plane that is radial relative to the vertical axis of rotation, is inclined relative to said axis. Each skid directly engages, via a portion of the outer radial surface thereof, with the cam surface of the shim. Equipment for converting hydraulic power into electrical power according to the invention includes a wheel that is rotatably secured to a shaft guided by such an adjustable system.