An electric vehicle propulsion control device includes a power converter that applies an alternating-current voltage to an induction machine and a controller that controls the power converter based on an external operation command. The controller includes a first calculation unit. The first calculation unit calculates, from current information (id and iq) detected at the induction machine and current command values (id*1 and iq*1) that are based on the operation command, a d-axis voltage command (Vd*1) and a q-axis voltage command (Vq*1) for the power converter, and a primary magnetic flux φds and a secondary magnetic flux φdr of the induction machine. The first calculation unit also adds to or subtracts from a term including the q-axis voltage command (Vq*1) an interference term stemming from the d-axis voltage command (Vd*1) in calculating a first speed ω1 that is a free-run speed of the induction machine.

An inverter controller according to an embodiment has an inverter main circuit, current detectors, a current command value calculator, a voltage command value calculator and an estimator. The inverter main circuit is capable of being electrically connected to a rotary drive target. The current detectors detect current values output from the inverter main circuit. The current command value calculator calculates current command values with which an output voltage output from the inverter main circuit becomes equal to or more than a target value. The voltage command value calculator calculates voltage command values with which the current values become equal to the current command values. The estimator calculates an estimated rotational phase angle of the rotary drive target, based on the voltage command values and the current values.

An inverter controller according to an embodiment has an inverter main circuit, current detectors, a current command value calculator, a voltage command value calculator and an estimator. The inverter main circuit is capable of being electrically connected to a rotary drive target. The current detectors detect current values output from the inverter main circuit. The current command value calculator calculates current command values with which an output voltage output from the inverter main circuit becomes equal to or more than a target value. The voltage command value calculator calculates voltage command values with which the current values become equal to the current command values. The estimator calculates an estimated rotational phase angle of the rotary drive target, based on the voltage command values and the current values.

An embodiment of a system for determining a sensor failure in a motor control system with at least three phase current measurements includes a magnitude computation module that determines a magnitude of a diagnostic voltage, the diagnostic voltage represented in a stator frame and based on a difference between an input voltage command and a final voltage command, and a phase evaluation module that determines a phase value of the diagnostic voltage based on the diagnostic voltage. The system also includes a sensor failure identification module that identifies a current sensor failure based on the phase value of the diagnostic voltage, the sensor failure represented by a failure signal, and a current calculation transition module that modifies a calculation scheme for determining a measurement of motor current based on the sensor failure.

Disclosed examples include motor drive power conversion systems with an inverter, as well as a controller methods to drive a motor in which output filter capacitor currents are computed and used to compensate the motor control in consideration of damping resistance values of an output filter.

A voltage controller generates a d-axis voltage command value and a q-axis voltage command value on the basis of a drive command signal and a three-phase current. When the state in which the absolute value of the resultant vector of the d-axis voltage command value and the q-axis voltage command value is not within a set predetermined range continues for a predetermined time or longer, a disconnection detector determines that a disconnection between a power converter and an AC motor has occurred. A gate controller transmits a gate command for turning off a switching element provided in the power converter to the power converter when the disconnection detector determines that a disconnection between the power converter and the AC motor has occurred.

A motor driving apparatus including a motor including a stator and a rotor rotating in the stator, an inverter configured to supply a driving voltage to a stator coil wound on the stator so as to rotate the rotor, and a control unit configured to, when a target command value is received, change a predetermined reference start-up time point to a start-up time point corresponding to an electrical angle position of the rotor in correspondence with the target command value per rotation of the rotor and to control the inverter to supply the driving voltage at the start-up time point.

A controller of an inverter control apparatus includes an A/D conversion unit that performs digital conversion of an input signal when a signal for either an A/D converter start trigger or an A/D converter start trigger is input thereinto; a first inverter control unit that generates the A/D converter start trigger which starts the A/D conversion unit, based on A/D converter start timing information and a first carrier signal; a second inverter control unit that generates the A/D converter start trigger which starts the A/D conversion unit, based on A/D converter start timing information and a second carrier signal; and an A/D start factor selection unit that receives either the A/D converter start trigger or the A/D converter start trigger and selects an A/D start factor at a predetermined period timing of an operation period of the first carrier signal and the second carrier signal.

A controller of an inverter control apparatus includes an A/D conversion unit that performs digital conversion of an input signal when a signal for either an A/D converter start trigger or an A/D converter start trigger is input thereinto; a first inverter control unit that generates the A/D converter start trigger which starts the A/D conversion unit, based on A/D converter start timing information and a first carrier signal; a second inverter control unit that generates the A/D converter start trigger which starts the A/D conversion unit, based on A/D converter start timing information and a second carrier signal; and an A/D start factor selection unit that receives either the A/D converter start trigger or the A/D converter start trigger and selects an A/D start factor at a predetermined period timing of an operation period of the first carrier signal and the second carrier signal.

A motor control apparatus operates in a first control mode in which the values of a torque current component and an excitation current component are controlled so that the difference between an instruction phase and a rotation phase is decreased and a second control mode in which constant current is supplied to a winding of a motor. The second control mode is switched to the first control mode if the rotation speed is varied from a value lower than a first threshold value to a value not lower than the first threshold value in the second control mode and the first control mode is kept even if the rotation speed is varied from a value not lower than the first threshold value to a value that is not lower than a second threshold value and that is lower than the first threshold value in the first control mode.