Control device and method for determining a p-V characteristic of at least one wheel brake cylinder of a brake system of a vehicle

A control device for a brake system of a vehicle, comprising:

• an electronic device configured to:
• actuate a wheel inlet valve of the brake system upstream of at least one wheel brake cylinder of the brake system and/or at least one isolating valve of the brake system upstream of the at least one wheel brake cylinder,
• increase a pressure prevailing in the at least one wheel brake cylinder, during a measurement time interval by displacing brake fluid via the at least one wheel inlet valve and/or via the at least one isolating valve into the at least one wheel brake cylinder, and
• setting a p-V characteristic of the at least one wheel brake cylinder, taking into consideration at least one volume variable determined during the measurement time interval and reflecting a present volume in the at least one wheel brake cylinder and at least one pressure variable that was determined at the same time and reflects a present pressure in the at least one wheel brake cylinder,
• wherein the electronic device is additionally configured to increase, before the measurement time interval, a pressure exerted on at least the at least one wheel inlet valve closed and/or the at least one isolating valve closed, with an average pressure build-up gradient of greater than or equal to 50 bar/second up to a limit pressure of greater than or equal to 25 bar during at least one pressure increase interval.

A brake system for a vehicle, comprising:

• a control device, including:
• an electronic device configured to:
• actuate a wheel inlet valve of the brake system upstream of at least one wheel brake cylinder of the brake system and/or at least one isolating valve of the brake system upstream of the at least one wheel brake cylinder,
• increase a pressure prevailing in the at least one wheel brake cylinder, during a measurement time interval by displacing brake fluid via the at least one wheel inlet valve and/or via the at least one isolating valve into the at least one wheel brake cylinder, and
• setting a p-V characteristic of the at least one wheel brake cylinder, taking into consideration at least one volume variable determined during the measurement time interval and reflecting a present volume in the at least one wheel brake cylinder and at least one pressure variable that was determined at the same time and reflects a present pressure in the at least one wheel brake cylinder,
• wherein the electronic device is additionally configured to increase, before the measurement time interval, a pressure exerted on at least the at least one wheel inlet valve closed and/or the at least one isolating valve closed, with an average pressure build-up gradient of greater than or equal to 50 bar/second up to a limit pressure of greater than or equal to 25 bar during at least one pressure increase interval;
• the at least one wheel brake cylinder;
• and
• the at least one wheel inlet valve upstream of the at least one wheel brake cylinder and/or the at least one isolating valve upstream of the at least one wheel brake cylinder.