1. A method of controlling a power converter of a motor drive system, said method comprising:
controlling said power converter during a first operating mode by applying a current control scheme, which sets power converter commands to control torque current flowing from said power converter to the motor to achieve desired motor speed;
initiating a second operating mode when power supply to said power converter is interrupted, wherein said second operating mode includes controlling a negative torque current between said power converter and said motor so that mechanical energy from said motor charges an element on a power supply side of said power converter;
controlling the torque current between said power converter and said motor to limit maximum transient DC bus voltage;
monitoring DC bus voltage between said power converter and said power supply; and
comparing the monitored DC bus voltage to a reference value:
wherein torque current between said power converter and said motor is controlled based on the result of said comparing step to limit a maximum DC bus voltage during transition between the first and second operating modes.
2. The method according to claim 1, wherein said element on the power supply side of said power converter is a DC link capacitor.
3. The method according to claim 1, wherein, during said second operating mode, said motor functions as a generator and said power converter functions as an active rectifier to charge said element.
4. The method according to claim 1, wherein said motor decelerates during second operating mode, and said method further comprises:
switching to said first operating mode after power input to said power converter is recovered.
5. The method according to claim 4, wherein said step of switching to said first operating mode after power input to said power converter is recovered is performed without a soft start sequence.
6. The method according to claim 4, wherein
said current control scheme in said first operating mode is applied based on motor speedposition information, and
said speedposition information is monitored during said second operating mode, such that a re-synchronization process is not needed upon switching to said first operating mode.
7. The method according to claim 1, wherein said power converter is an inverter.
8. The method according to claim 1, wherein said power converter is connected to a DC power supply via a DC link, wherein DC link voltage in said second operating mode is higher than DC link voltage in said first operating mode.
9. (canceled)
10. The method according to claim 1, wherein
said current control scheme in said first operating mode is applied based on motor speedposition information, and
said motor drive system is a speed sensorless system.
11. The method according to claim 1, wherein
said current control scheme in said first operating mode is applied based on motor speedposition information, and
said motor drive system includes a motor speed sensor.
12. The method according to claim 1, wherein
said second operating mode provides ride through capability during power interruption.
13. The method according to claim 1, wherein said motor drive system is an aerospace motor drive system.
14. The method according to claim 1, wherein transition between said first and second operating modes is a hard switch.
15. A power converter controlling apparatus for controlling a power converter of a motor drive system, said controlling apparatus comprising:
a current controller, which outputs gating signals to said power converter as a function of a torque current reference and a flux current reference; and
a torque current reference generator, which generates the torque current reference used by said current controller, wherein
said current controller controls said power converter during a first operating mode to create torque current flowing from said power converter to the motor to achieve desired motor speed;
controls the power converter in a second operating mode, initiated when power to said power converter is interrupted, so that negative torque current between said power converter and said motor draws mechanical energy from said motor and charges an element on a power supply side of said power converter; and
controls the torque current between said power converter and said motor to limit maximum transient bus voltage;
wherein said torque current reference generator:
monitors DC bus voltage between said power converter and the power supply;
compares the monitored DC bus voltage to a reference value: and
controls a torque current reference based on the result of said comparing step to limit a maximum DC bus voltage during transition between the first and second operating modes.
16. The apparatus according to claim 15, wherein said element on the power supply side of said power converter is a DC link capacitor.
17. The apparatus according to claim 15, wherein, during said second operating mode, said motor functions as a generator and said power converter functions as an active rectifier to charge said element.
18. The apparatus according to claim 15, wherein said motor decelerates during second operating mode, and said torque current reference generator:
switches to said first operating mode after power input to said power converter is recovered.
19. The apparatus according to claim 18, wherein said torque current reference generator switches to said first operating mode after power input to said power converter is recovered without requiring a soft start sequence.
20. The apparatus according to claim 15, wherein
said first operating mode is applied based on motor speedposition information, and
said torque current reference generator monitors speedposition information during said second operating mode, such that a re-synchronization process is not needed upon switching to said first operating mode.
21. The apparatus according to claim 15, wherein said power converter is an inverter.
22. The apparatus according to claim 15, wherein said power converter is connected to a DC power supply via a DC link, wherein DC link voltage in said second operating mode is higher than DC link voltage in said first operating mode.
23. (canceled)
24. The apparatus according to claim 15, wherein
said current control scheme in said first operating mode is applied based on motor speedposition information, and
said motor drive system is a speed sensorless system.
25. The apparatus according to claim 15, wherein
said current control scheme in said first operating mode is applied based on motor speedposition information, and
said motor drive system includes a motor speed sensor.
26. The apparatus according to claim 15, wherein
said second operating mode provides ride through capability during power interruption.
27. The apparatus according to claim 15, wherein said motor drive system is an aerospace motor drive system.
28. The apparatus according to claim 15, wherein transition between said first and second operating modes is a hard switch.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1-5. (canceled)
6. A supporting structure for a motor vehicle, in particular an automobile, comprising:
a longitudinal beam arrangement, and
a bumper arrangement attached to at least one longitudinal end of the longitudinal beam arrangement, the bumper arrangement having a crossbeam which, in an axial direction, rests against the longitudinal beam arrangement by way of two longitudinal beam parts,
wherein the longitudinal beam parts are attached to a central section of the crossbeam which is located at a distance from ends of the crossbeam,
wherein the longitudinal beam parts, at their ends remote from the crossbeam, are attached by way of a bearing bracket to one another and to the longitudinal beam arrangement,
wherein the bearing bracket is a crash element, which exercises an energy-absorbing effect in the event of a crash,
wherein the bumper arrangement has a bending beam attached to the ends of the crossbeam, and
wherein the bending beam, at least in the central section, rests on the crossbeam by way of at least one energy-absorbing foam body.
7. The supporting structure as claimed in claim 6, wherein the longitudinal beam parts run parallel to a longitudinal direction of the vehicle and at a distance from one another in a horizontal direction.
8. The supporting structure as claimed in claim 6, wherein the longitudinal beam arrangement is arranged essentially in the center of the vehicle.
9. The supporting structure as claimed in claim 6, wherein the bending beam is supported at its ends on the crossbeam such that it can rotate about vertical axes.
10. The supporting structure as claimed in claim 6, wherein the bending beam is attached exclusively at its ends to the crossbeam.
11. The supporting structure as claimed in claim 7, wherein the longitudinal beam arrangement is arranged essentially in the center of the vehicle.
12. The supporting structure as claimed in claim 7, wherein the bending beam is supported at its ends on the crossbeam such that it can rotate about vertical axes.
13. The supporting structure as claimed in claim 7, wherein the bending beam is attached exclusively at its ends to the crossbeam.
14. The supporting structure as claimed in claim 8, wherein the bending beam is supported at its ends on the crossbeam such that it can rotate about vertical axes.
15. The supporting structure as claimed in claim 8, wherein the bending beam is attached exclusively at its ends to the crossbeam.
16. The supporting structure as claimed in claim 9, wherein the bending beam is attached exclusively at its ends to the crossbeam.
17. The supporting structure as claimed in claim 11, wherein the bending beam is supported at its ends on the crossbeam such that it can rotate about vertical axes.
18. The supporting structure as claimed in claim 11, wherein the bending beam is attached exclusively at its ends to the crossbeam.
19. The supporting structure as claimed in claim 14, wherein the bending beam is attached exclusively at its ends to the crossbeam.
20. The supporting structure as claimed in claim 17, wherein the bending beam is attached exclusively at its ends to the crossbeam.