Method and device for overload detection in battery-operated devices having an electric motor
AssigneeRobert Bosch GmbH
InventorCornelius Liebenow
Life of this patent
Estimating the term…
Abstract
In a method for detecting an overload situation in a battery-operated device having an electric motor, a load current of the electric motor is ascertained and used to deduce a thermal overload of the battery in such a manner, that, starting out from a static temperature limit, a temporally variable, maximum permissible temperature limit for the battery is calculated using a specifiable function dependent on the ascertained load current. The calculated, variable temperature limit is compared to a current, measured temperature of the battery, and a thermal overload of the battery is deduced from the result of the comparison.
Claims14
A method for detecting an overload situation in a battery-operated device having an electric motor, comprising:
- ascertaining, by a device, a load current of the electric motor;
- calculating, by a logic device, a temporally variable, maximum permissible temperature limit for the battery based on a specifiable function dependent on the ascertained load current, the function assuming a maximum value, which corresponds to a specifiable static temperature limit, in response to a zero load current;
- comparing, by the logic device, the calculated, variable temperature limit to a current, measured temperature of the battery;
- and
- deducing, by the logic device, a thermal overload of the battery in accordance with a result of the comparison.
A monitoring apparatus for a battery-operated device having an electric motor operable by a storage battery, for detecting an overload situation, comprising:
- a device adapted to ascertain a load current of the electric motor;
- a logic device adapted to implement a specifiable function dependent on the ascertained load current, in order to calculate a temporally variable temperature limit from a maximum permissible, static temperature limit stored in the logic device and to compare the temporally variable temperature limit to a current temperature of the battery measured by a sensor, in order to deduce a thermal overload of the battery therefrom.
Dependencies are inferred from the claim text.