Patent ID: 6710558
Filing Date: 2004-03-23
Classification: F04D,H02H,H02P

Abstract:
An electronically commutatable motor for a fluid pump, comprising:a temperature sensor configured to monitor a temperature in a housing chamber of the fluid pump; a commutation device; semiconductor switches controlled by control signals of the commutation device; excitation windings connectable to a DC supply voltage and disconnectable therefrom via the semiconductor switches; and a PWM generator, the control signals of the commutation device being clocked by pulse width modulatable output signals of the PWM generator, a pulse width ratio thereof being modifiable as a function of an output signal of the temperature sensor; wherein the PWM generator is configured to operate with one of a defined and a definable operating pulse width ratio up to one of a defined and a definable temperature; wherein the PWM generator is configured to modify the pulse width ratio as a function of the output signal of the temperature sensor after the one of the defined and the definable temperature is reached; wherein the motor is configured to be switch off by way of the PWM generator in accordance with the output signal of the temperature sensor when a limit temperature in the housing chamber is reached; and wherein the pulse width ratio one of increases and decreases as the temperature in the housing chamber rises.