Method for operating a hydraulic system and brake system

A method for operating a hydraulic brake system for motor vehicles, comprising:

• multiple consumers,
• an electrically controllable pressure providing device that can output a pressure medium volume for the purpose of actuating the consumer, wherein the pressure medium volume (V) that is output or received by the pressure providing device and the system pressure (P) that is provided by the pressure providing device can be determined, and
• an electrically controllable inlet valve for each consumer that is arranged between the pressure providing device and the consumer, wherein a non-return valve that is open in the direction of the pressure providing device is connected in each case in parallel to the inlet valves,
• wherein a pressure volume ratio (Fi) is predetermined or determined for each consumer and for a time interval (Δtn) each consumer is allocated to a first group or a second group of consumers, wherein the first group of consumers comprises at least one consumer and that for the purpose of setting predetermined, consumer-specific desired pressures (pidesired)
• the first group of consumers is or will be connected to the pressure providing device by way of in each case the opened inlet valve so that the first group is influenced by the system pressure (P, Padesired) of the pressure providing device, and
• the inlet valves of the consumers of the second group are or will be closed, wherein the inlet valve of an individual, selected consumer of the second group is opened in a regulated manner for the purpose of building up a pressure.