State estimation for controlling a drive machine without sensors
View Patent ↗Methods, apparatuses, and systems are provided for controlling an electrical drive machine. Actuator stator currents of the electrical drive machine are measured. A manifestation of an internal state of the electrical drive machine are estimated based on the measured actuator stator currents. A quality criterion is ascertained for the estimated manifestation of the internal state of the electrical drive machine. The estimated manifestation is forwarded if the quality criterion is satisfied.
1 . A method for controlling an electrical drive machine of a motor vehicle, comprising:
measuring actual stator currents of the electrical drive machine;
estimating an internal state of the electrical drive machine as an estimated internal state based on the measured actual stator currents;
determining a desired internal state of the electrical drive machine based on the estimated internal state of the electrical drive machine;
determining a plurality of sets of successively actuatable fundamental voltage space vectors for the electrical drive machine, which are ascertained for successive sampling times;
determining constraints on actuation of the electrical drive machine based on boundary conditions of the motor vehicle, which include surrounding traffic, atmospheric influences, and road conditions of the motor vehicle, and based on limits for motor operation of the electrical drive machine;
selecting one of the plurality of sets of successively actuatable fundamental voltage space vectors for the electrical drive machine based on at least one selection criterion, which is determined based on the constraints; and
actuating an inverter of the electrical drive machine with the selected set of successively actuatable fundamental voltage space vectors using direct triggers to achieve the desired internal state of the electrical drive machine.
2 . The method according to claim 1 , further comprising:
ascertaining that a quality criterion is satisfied for the estimated internal state of the electrical drive machine.
3 . The method according to claim 2 , further comprising:
forwarding the estimated internal state of the electrical drive machine if the quality criterion is satisfied.
4 . The method according to claim 2 , wherein
the quality criterion comprises a comparison of the estimated internal state of the electrical drive machine with the measured actual stator currents.
5 . The method according to claim 2 , wherein
the quality criterion takes into consideration a mean squared error and/or a total harmonic distortion of the estimated internal state in order to assess a variance and/or a distortion of the estimation of one or in each case multiple parameters pertaining to the internal state of the electrical drive machine.
6 . The method according to claim 2 , wherein
the estimation is repeated for each of a multiplicity of successive sampling times, and
the estimated internal state is forwarded as soon as the quality criterion is or was satisfied.
7 . The method according to claim 2 , further comprising:
determining a measure of quality for the satisfaction of the quality criterion.
8 . The method according to claim 1 , wherein
the estimation involves taking into consideration variances and/or covariances of the internal state of the electrical drive machine.
9 . The method according to claim 1 , wherein
the internal state of the electrical drive machine is estimated using a nonlinear adaptive observer.
10 . The method according to claim 9 , wherein
the nonlinear adaptive observer comprises an extended stochastic filter.
11 . An electronic control unit for an electrical drive machine of a motor vehicle, comprising:
a sensor for determining actual stator currents of the electrical drive machine; and
an estimator for determining an estimated internal state of the electrical drive machine, wherein
the electronic control unit is configured to perform the method according to claim 1 .
12 . An electrical machine for propelling a motor vehicle comprising the electronic control unit of claim 11 .