Controller for power convertor and motor driving system
AssigneesWisconsin Alumni Research Foundation, Toshiba Mitsubishi-Electric Industrial Systems Corporation
InventorsYang Xu, Chikara Morito, Robert D. Lorenz
Life of this patent
Estimating the term…
Abstract
A controller for a power convertor includes: a torque command value calculation module to calculate a first torque command value to a power convertor; a torque command limit module to receive the first torque command value and generate a second torque command value obtained by correcting the first torque command value so that the first torque command value is limited to a torque limiter range. The torque command limit module sets a width between the upper limit torque value and the lower limit torque value of the torque limiter range to be smaller as a fundamental wave output frequency of the power convertor increases at least in a speed region equal to or higher than a field weakening starting point.
Claims13
A controller for a power convertor, the controller comprising:
- a torque command value calculation module configured to calculate a first torque command value to a power convertor based on a speed command value of a motor driven by the power convertor;
- a torque command limit module configured to receive the first torque command value and generate a second torque command value obtained by correcting the first torque command value so that the first torque command value is limited to a torque limiter range defined by an upper limit torque value calculated by a predetermined calculation formula for upper limit torque command value calculation and a lower limit torque value obtained by multiplying the upper limit torque value by a predetermined negative coefficient or zero;
- a flux command generation module configured to generate a stator flux command value in accordance with a fundamental wave output frequency of output from the power convertor;
- and
- an output voltage command module configured to:
- calculate an output voltage command value of the power convertor based on the second torque command value and the stator flux command value;
- generate a pulse width modulation signal based on the output voltage command value;
- and
- transmit the pulse width modulation signal,
- wherein the torque command limit module calculates the upper limit torque value to be smaller as the fundamental wave output frequency increases at least in a speed region equal to or higher than a field weakening starting point.
A controller for a power convertor, the controller comprising:
- a torque command value calculation module configured to calculate a torque command value to a power convertor based on a speed command value of a motor driven by the power convertor;
- a voltage command value calculation module configured to calculate a voltage command value to the power convertor based on the torque command value calculated by the torque command value calculation module;
- a flux estimation module configured to calculate estimated values of the stator flux and rotor flux of the motor in a subsequent control period based on the voltage command value to the power convertor and a measured stator current of the motor;
- a motor speed estimation module configured to calculate an estimated value of a speed of the motor in a subsequent control period based on the estimated value of the rotor flux calculated by the flux estimation module;
- and
- an inverter controller configured to:
- generate a pulse width modulation signal based on at least one of the torque command value, the voltage command value, the estimated values of the stator flux, or the speed of the motor in a subsequent control period;
- and
- transmit the pulse width modulation signal.
Dependencies are inferred from the claim text.