Current measurement apparatus, current measurement program, and current measurement method

A current measurement program, applicable to a control apparatus for at least one multiphase rotary electric machine, for measuring phase currents flowing through respective multiphase power lines used for power supply to the at least one multiphase rotary electric machine, the current measurement program causing a computer to execute:

• a measured current acquiring step of acquiring, from a current sensor, a measured value of at least one target phase current flowing through a corresponding at least one target phase power line included in the multiphase power lines;
• and
• a correction step of:
• calculating an error arising in the measured value of the at least one target phase current due to magnetic flux generated from each of the multiphase power lines in accordance with an error factor defined for each of the multiphase power lines with respect to the at least one target phase current,
• the error factor defined for each of the multiphase power lines with respect to the at least one target phase current being a constant value or a variable determined based on (i) one or more shields located between the current sensor and the corresponding one of the multiphase power lines and (ii) a distance between the current sensor and the corresponding one of the multiphase power lines;
• and
• correcting the measured value of the at least one target phase current based on the calculated error.

A current measurement method, applicable to a control apparatus for at least one multiphase rotary electric machine, for measuring phase currents flowing through respective multiphase power lines used for power supply to the at least one multiphase rotary electric machine, the current measurement method comprising:

• a measured current acquiring step of acquiring, from a current sensor, a measured value of at least one target phase current flowing through a corresponding at least one target phase power line included in the multiphase power lines;
• and
• a correction step of:
• calculating an error arising in the measured value of the at least one target phase current due to magnetic flux generated from each of the multiphase power lines in accordance with an error factor defined for each of the multiphase power lines with respect to the at least one target phase current,
• the error factor defined for each of the multiphase power lines with respect to the at least one target phase current being a constant value or a variable determined based on (i) one or more shields located between the current sensor and the corresponding one of the multiphase power lines and (ii) a distance between the current sensor and the corresponding one of the multiphase power lines;
• and
• correcting the measured value of the at least one target phase current based on the calculated error.