Abstract: An electric motor driving apparatus controls driving of an electric motor having two or more phase windings whose ends are open by using first and second inverters. A control unit includes a first inverter control circuit and a second inverter control circuit. The first inverter control circuit generates a first voltage command as an output voltage command to the first inverter based on a torque command. The second inverter control circuit generates a second voltage command as an output voltage command to the second inverter. The control unit determines a composite voltage command based on a first voltage command vector and a second voltage command including a case, in which a pure phase difference between the first voltage command vector on a dq coordinate corresponding to the first voltage command and the second voltage command vector on the dq coordinate corresponding to the second voltage command is other than 180°.

Abstract: An electric motor driving apparatus controls driving of an electric motor having two or more phase windings whose ends are open by using first and second inverters. A control unit includes a first inverter control circuit and a second inverter control circuit. The first inverter control circuit generates a first voltage command as an output voltage command to the first inverter based on a torque command. The second inverter control circuit generates a second voltage command as an output voltage command to the second inverter. The control unit determines a composite voltage command based on a first voltage command vector and a second voltage command including a case, in which a pure phase difference between the first voltage command vector on a dq coordinate corresponding to the first voltage command and the second voltage command vector on the dq coordinate corresponding to the second voltage command is other than 180°.

Abstract: An abnormality diagnosis apparatus includes a power consumption estimation section that estimates power consumption of a motor, which is driven by power supplied from a power supply, and power consumption of an auxiliary unit using the power to calculate a power consumption estimate value, a power-supply voltage estimation section that calculates a power-supply voltage estimate value, which is an estimate value of voltage of the power supply, based on the power consumption estimate value and a power-supply current detection value, which is based on a detection value of a power-supply current sensor detecting a current of the power supply, and an abnormality determination section that determines an abnormality of a power-supply voltage sensor detecting a voltage of the power supply, based on a comparison result between the power-supply voltage estimate value and a power-supply voltage detection value, which is based on a detection value of the power-supply voltage sensor.

Abstract: In a diagnostic device, a determiner determines whether a rotational speed of an AC motor is within a low rotational-speed range in which its rotational speed is approximately zero. An input-voltage estimate calculator calculates, as an input-voltage estimate, an estimate of an input voltage to an inverter when it is determined that the rotational speed of the AC motor is within the low rotational-speed range. A malfunction determiner performs a diagnostic task. The diagnostic task calculates an absolute value of a difference between an input-voltage measurement value measured by an input voltage sensor and the input-voltage estimate. The diagnostic task determines whether the absolute value of the difference is higher than a predetermined voltage threshold. The diagnostic task determines that there is a malfunction in the input voltage sensor upon determining that the absolute value of the difference is higher than the predetermined voltage threshold.

Abstract: A voltage sensor abnormality diagnosis apparatus is applied to a motor controller operating switching of inverter by a switching signal for complementary on and off and diagnoses abnormality of input voltage sensor. An input voltage estimated value calculation section calculates input voltage estimated value by multiplying voltage command amplitude deviation by conversion coefficient, the voltage command amplitude deviation being obtained by subtracting theoretical voltage command amplitude, which is amplitude of theoretical voltage command calculated by using a motor model expression, from a control voltage command amplitude, which is an amplitude of a control voltage command calculated by feedback control and has been corrected by the dead time correction amount. An abnormality determination section determines that the input voltage sensor is abnormal if an absolute value of a difference between an input voltage sensor value and the input voltage estimated value is larger than a voltage threshold value.

Abstract: A voltage sensor abnormality diagnosis apparatus is applied to a motor controller operating switching of inverter by a switching signal for complementary on and off and diagnoses abnormality of input voltage sensor. An input voltage estimated value calculation section calculates input voltage estimated value by multiplying voltage command amplitude deviation by conversion coefficient, the voltage command amplitude deviation being obtained by subtracting theoretical voltage command amplitude, which is amplitude of theoretical voltage command calculated by using a motor model expression, from a control voltage command amplitude, which is an amplitude of a control voltage command calculated by feedback control and has been corrected by the dead time correction amount. An abnormality determination section determines that the input voltage sensor is abnormal if an absolute value of a difference between an input voltage sensor value and the input voltage estimated value is larger than a voltage threshold value.

Abstract: An abnormality diagnosis apparatus includes a power consumption estimation section that estimates power consumption of a motor, which is driven by power supplied from a power supply, and power consumption of an auxiliary unit using the power to calculate a power consumption estimate value, a power-supply voltage estimation section that calculates a power-supply voltage estimate value, which is an estimate value of voltage of the power supply, based on the power consumption estimate value and a power-supply current detection value, which is based on a detection value of a power-supply current sensor detecting a current of the power supply, and an abnormality determination section that determines an abnormality of a power-supply voltage sensor detecting a voltage of the power supply, based on a comparison result between the power-supply voltage estimate value and a power-supply voltage detection value, which is based on a detection value of the power-supply voltage sensor.

Abstract: In a diagnostic device, a determiner determines whether a rotational speed of an AC motor is within a low rotational-speed range in which its rotational speed is approximately zero. An input-voltage estimate calculator calculates, as an input-voltage estimate, an estimate of an input voltage to an inverter when it is determined that the rotational speed of the AC motor is within the low rotational-speed range. A malfunction determiner performs a diagnostic task. The diagnostic task calculates an absolute value of a difference between an input-voltage measurement value measured by an input voltage sensor and the input-voltage estimate. The diagnostic task determines whether the absolute value of the difference is higher than a predetermined voltage threshold. The diagnostic task determines that there is a malfunction in the input voltage sensor upon determining that the absolute value of the difference is higher than the predetermined voltage threshold.