Control apparatus for electric rotating machine
AssigneeDenso Corporation
InventorsYuya Fujishima, Akiyoshi Morii
Life of this patent
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Abstract
Upon determining that the absolute value of an electrical angular speed of a motor-generator is smaller than or equal to a threshold value, a control apparatus compensates a current detected by a U-phase current sensor based on a temperature detected by a U-phase temperature sensor and compensates a current detected by a V-phase current sensor based on an estimated temperature of a V-phase current sensor. On the other hand, upon determining that the absolute value of the electrical angular speed is larger than the threshold value, the control apparatus compensates the currents detected by the U-phase and V-phase current sensors based on temperature detected by the U-phase temperature sensor.
Claims9
A control apparatus for use in a control system which includes a power conversion circuit for applying an AC voltage to a three-phase electric rotating machine in accordance with power supplied, current sensors provided corresponding to at least two of three phases of the electric rotating machine to detect phase currents of the electric rotating machine, and a temperature sensor provided corresponding to at least one of the current sensors for detecting temperature of the current sensor,
- a first current sensor being one of the current sensors, a temperature of the first current sensor being detected by one temperature sensor of the temperature sensors,
- a second current sensor being one of the current sensors other than the first current sensor,
- the control apparatus comprising:
- a controller configured to act as:
- a temperature increase amount estimation section that estimates, for each of all the current sensors, an amount of temperature increase of the current sensors due to a current flowing through the phase in which the current sensor is provided based on a current flowing through the current sensor;
- a reference temperature calculation section that calculates a reference temperature by subtracting the temperature increase amount of the first current sensor from a temperature detection value of the temperature sensor;
- a temperature estimation section that estimates temperature of the second current sensor by adding the reference temperature to the temperature increase amount of the second current sensor;
- a speed determination section that determines whether a rotational speed of the electric rotating machine is in a high speed region higher than a threshold speed or in a low speed region lower than or equal to the threshold speed;
- a low speed rotation compensation section that compensates a current detection value of the first current sensor based on the temperature detection value of the temperature sensor, and compensates the current detection value of the second current sensor based on the temperature of the second current sensor estimated by the temperature estimation section on condition that the rotational speed is determined to be in the low speed region by the speed determination section;
- a high speed rotation compensation section that compensates a current detection value of each of all the current sensors based on the temperature detection value of each temperature sensor without using the temperature of the non second current sensor estimated by the temperature estimation section on condition that the rotational speed is determined to be in the high speed region by the speed determination section;
- and
- a control section that controls a controlled variable of the electric rotating machine by manipulating supply of power to the power conversion circuit using the compensated current detection value of each current sensor.
Dependencies are inferred from the claim text.