Method for optimizing the efficiency of a motor operated under a load
The invention relates to a method to optimize the efficiency of a motor operated under a load having an essentially quadratic characteristic curve, the motor being connected to a motor control with whose aid at least one free motor parameter w can be changed to influence the efficiency. According to the invention, the rotational speed n and the input power P E are determined and the motor parameter w is adjusted to a value at which the value E representing the quotient of the cube of the rotational speed n and the input power P E attains a maximum.
1. A method to optimize the efficiency η of a motor ( 10 ) operated under a load having an essentially quadratic characteristic curve ( 21 ), the motor being connected to a motor control ( 11 ) with whose aid at least one free motor parameter w can be changed to influence the efficiency η,
characterized in that
the rotational speed n of the motor is repeatedly determined,
that the input power P E is repeatedly determined, and
that the motor parameter w is adjusted to a value at which the value E representing the quotient of the cube of the rotational speed n and the input power P E attains a maximum.
2. A method according to claim 1 , characterized in that an electronically commutated DC motor is used as the motor.
3. A method according to claim 2 , characterized in that a commutation angle is used as the motor parameter.
4. A method according to claim 1 , characterized in that the input power P E is determined from motor current I DC and motor voltage U DC .
5. A method according to claim 1 , characterized in that an internal combustion engine is used as the motor.
6. A method according to claim 1 , characterized in that an ignition point is used as the motor parameter.
7. A method according to claim 1 , characterized in that the input power is determined on the basis of fuel consumption.
8. A method according to claim 1 , characterized in that the motor is used to drive fans or pumps.
9. A device to optimize the efficiency h of a motor ( 10 ) operated under a load having an essentially quadratic characteristic curve ( 21 ), according to the method in accordance with claims 1 – 6 , which comprises:
a means of recording the rotational speed n of the motor,
a means of recording the input power P E of the motor, and
a motor control ( 11 ) with whose aid at least one free motor parameter w can be changed to influence the efficiency h, the motor parameter w being adjusted to a value at which the value E representing the quotient of the cube of the rotational speed n and the input power P E attains a maximum.
10. A device according to claim 9 , characterized in that a commutation angle is the motor parameter.