摘要:
A resistance calculation activator determines whether or not an electric car is stopped on the basis of a drive command signal and an external signal, and activates a resistance calculator if a powering command is input as the drive command when it is determined that the electric car is stopped. The activated resistance calculator computes, within a resistance calculation period, a resistance value of an AC motor that produces driving force for the electric car, on the basis of a d-axis voltage command value and a d-axis current value supplied to the AC motor.
摘要:
A vector control device includes a vector control unit computing an output voltage output from the electric power converter according to vector control based on torque command and flux command and generating a PWM signal for controlling the electric power converter based on the output voltage, a first flux-command generation unit generating a flux command for asynchronous PWM mode, and a second flux-command generation unit generating a flux command for synchronous PWM mode. When an output frequency of the electric power converter is lower than a predetermined value, a flux command generated by the first flux-command generation unit is input to the vector control unit, and when the output frequency of the electric power converter is equal to or higher than a predetermined value, a flux command generated by the second flux-command generation unit is input to the vector control unit.
摘要:
A power conversion control device includes a modulation-wave generating unit generating a modulation wave based on output voltage phase angle command and modulation factor, a carrier-wave generating unit that, in a case of non-overmodulation state, generates a triangular wave or saw-tooth wave as the carrier wave, and, in a case of overmodulation state, generates, as the carrier wave, a signal fixed to −1 in a first section that is a predetermined range centering on timing corresponding to a peak position of the modulation wave, generates, as the carrier wave, a signal fixed to +1 in a second section obtained by shifting the first section by a half cycle of the modulation wave, and generates, as the carrier wave, a triangular wave or saw-tooth wave in remaining third section, and a comparing unit that compares the carrier wave and the modulation wave and generates a switching signal.
摘要:
A resistance calculation activator determines whether or not an electric car is stopped on the basis of a drive command signal and an external signal, and activates a resistance calculator if a powering command is input as the drive command when it is determined that the electric car is stopped. The activated resistance calculator computes, within a resistance calculation period, a resistance value of an AC motor that produces driving force for the electric car, on the basis of a d-axis voltage command value and a d-axis current value supplied to the AC motor.
摘要:
A power conversion control device includes a modulation-wave generating unit generating a modulation wave based on output voltage phase angle command and modulation factor, a carrier-wave generating unit that, in a case of non-overmodulation state, generates a triangular wave or saw-tooth wave as the carrier wave, and, in a case of overmodulation state, generates, as the carrier wave, a signal fixed to −1 in a first section that is a predetermined range centering on timing corresponding to a peak position of the modulation wave, generates, as the carrier wave, a signal fixed to +1 in a second section obtained by shifting the first section by a half cycle of the modulation wave, and generates, as the carrier wave, a triangular wave or saw-tooth wave in remaining third section, and a comparing unit that compares the carrier wave and the modulation wave and generates a switching signal.
摘要:
A vector control device includes a vector control unit computing an output voltage output from the electric power converter according to vector control based on torque command and flux command and generating a PWM signal for controlling the electric power converter based on the output voltage, a first flux-command generation unit generating a flux command for asynchronous PWM mode, and a second flux-command generation unit generating a flux command for synchronous PWM mode. When an output frequency of the electric power converter is lower than a predetermined value, a flux command generated by the first flux-command generation unit is input to the vector control unit, and when the output frequency of the electric power converter is equal to or higher than a predetermined value, a flux command generated by the second flux-command generation unit is input to the vector control unit.
摘要:
A control apparatus for an AC rotating machine that can reliably and stably start up an AC rotating machine, particularly a synchronous motor using a permanent magnet, in position-sensorless vector control thereof, includes: a steady speed calculator that calculates, during steady state control of the AC rotating machine, a rotation angular frequency of the AC rotating machine based on an AC current and voltage commands; and a start-up speed calculator that calculates, during start-up control within a predetermined period after the AC rotating machine has been started up, the rotation angular frequency of the AC rotating machine based on the AC current and the voltage commands. The control apparatus corrects during the start-up control current commands so that the AC voltage amplitude of the voltage commands will be a constant value not more than the maximum output voltage of a power converter.
摘要:
A control apparatus for an AC rotating machine that can reliably and stably start up an AC rotating machine, particularly a synchronous motor using a permanent magnet, in position-sensorless vector control thereof, includes: a steady speed calculator that calculates, during steady state control of the AC rotating machine, a rotation angular frequency of the AC rotating machine based on an AC current and voltage commands; and a start-up speed calculator that calculates, during start-up control within a predetermined period after the AC rotating machine has been started up, the rotation angular frequency of the AC rotating machine based on the AC current and the voltage commands. The control apparatus corrects during the start-up control current commands so that the AC voltage amplitude of the voltage commands will be a constant value not more than the maximum output voltage of a power converter.
摘要:
A control apparatus for an AC rotary machine includes a control circuit, a power converter, a current detector, and a voltage detector. The control circuit includes: an activation current instruction unit which generates a current instruction for activation; and a start phase setting unit which sets an initial rotation phase for activation control, based on the rotation direction of the AC rotary machine just after activation and on the polarity of current detected by the current detector just after activation. Thus, the current amplitude and torque shock just after activation control is started can be reduced, and assured and stable reactivation is allowed without causing the protection operation.
摘要:
A control apparatus for an AC rotary machine includes: a current detection section detecting current from a power converter to the AC rotary machine; and a control section generating a three-phase AC voltage instruction to the power converter, based on current detected by the current detection section and a torque instruction. The control section includes: an observer calculating a magnetic flux estimated value of the AC rotary machine, based on detected current and the voltage instruction; a current instruction calculation unit calculating current instruction values on rotational two axes, based on the torque instruction and the magnetic flux estimated value from the observer; and a voltage instruction calculation unit calculating the voltage instruction, based on the current instruction values from the current instruction calculation unit and the magnetic flux estimated value from the observer.