A method and a device for assigning the inductance or admittance to the rotor position of a synchronous machine having a stator and a rotor with or without permanent magnets. In operation, the synchronous machine is activated by way of timed terminal voltages and the inductance or admittance is calculated from the terminal voltages and the measured current response. In this case, the variation of the inductance or admittance over the rotor rotation under the boundary condition of an at least two-dimensional current vector that is unchanged in stator coordinates, is used as key information for the positional assignment.

A method of operating a Brushless Direct Current Motor (BLDCM), the BLDCM of the type including: a series of concentric independently activated electromagnetic phase coils interacting with a series of permanent magnets to provide relative movement therebetween, the phase coils having temporal periods of activation time and deactivation time, the method including the steps of: (a) activating at least one of the phase coils for a short period of activation; and (b) measuring the voltage response across the phase coil of the deactivated phase coil during the short period of activation to determine the rotor position.

Methods and an apparatuses for determining the movement of a synchronous machine are provided. An apparatus for determining the movement of a synchronous machine includes a determination for at least one electrical magnitude of the synchronous machine; a determination of the position error of the rotor of the synchronous machine, which is fitted to determine the position error of the rotor on the basis of the aforementioned at least one electrical magnitude of the synchronous machine; and also a correction of the movement signal of the incremental sensor, which is fitted to correct the read movement signal of the incremental sensor on the basis of the aforementioned determination of the position error of the rotor of the synchronous machine.

Methods and an apparatuses for determining the movement of a synchronous machine are provided. An apparatus for determining the movement of a synchronous machine includes a determination for at least one electrical magnitude of the synchronous machine; a determination of the position error of the rotor of the synchronous machine, which is fitted to determine the position error of the rotor on the basis of the aforementioned at least one electrical magnitude of the synchronous machine; and also a correction of the movement signal of the incremental sensor, which is fitted to correct the read movement signal of the incremental sensor on the basis of the aforementioned determination of the position error of the rotor of the synchronous machine.

Power based self-sensing of a rotor position of an SR motor at mid to high speeds and low torque is achieved by an SR motor control system by comparing the motor power to an injection maximum power. A position current pulse is injected to a stator pole in response to the motor power being less than the injection maximum power. An actual stator current created by the position current pulse is compared to an estimated stator current, and a stored estimated rotor position in a memory is updated to a new estimated rotor position if the actual stator current is not equal to the estimated stator current.

A motor control apparatus includes an excitation unit and a control unit. The excitation unit includes switching elements connected to a power supply and to different motor coils. The excitation unit excites an excitation phase targeted for excitation among motor excitation phases by the control unit driving the switching elements. When the excitation phases are excited, the control unit drives, in a first time period and based on a first PWM signal, a first switching element connected to a first phase coil corresponding to a first phase of the excitation phase targeted for excitation and, in a second time period and based on a second PWM signal, drives a second switching element connected to a second phase coil corresponding to a second phase of the excitation phase. The control unit controls outputting a duty ratio of the second PWM signal to the second switching element in the second time period.

A method of operating a Brushless Direct Current Motor (BLDCM), the BLDCM of the type including: a series of concentric independently activated electromagnetic phase coils interacting with a series of permanent magnets to provide relative movement therebetween, the phase coils having temporal periods of activation time and deactivation time, the method including the steps of: (a) activating at least one of the phase coils for a short period of activation; and (b) measuring the voltage response across the phase coil of the deactivated phase coil during the short period of activation to determine the rotor position.

A motor control apparatus, includes: a voltage control unit configured to control a voltage to apply to a plurality of coils in order to cause a rotor of a motor that includes the plurality of coils to rotate; a holding unit configured to hold information that indicates a magnitude of a load of the motor; and a detection unit configured to, based on the information that indicates the magnitude of the load that is held by the holding unit, set a detection condition for a stop position of the rotor, and perform detection processing of the stop position of the rotor in accordance with the set detection condition.

A motor control apparatus, includes: a voltage control unit configured to control a voltage to apply to a plurality of coils in order to cause a rotor of a motor that includes the plurality of coils to rotate; a holding unit configured to hold information that indicates a magnitude of a load of the motor; and a detection unit configured to, based on the information that indicates the magnitude of the load that is held by the holding unit, set a detection condition for a stop position of the rotor, and perform detection processing of the stop position of the rotor in accordance with the set detection condition.

A motor control apparatus excites an excitation phase targeted for excitation among a plurality of excitation phases of a motor. The motor control apparatus, in a state in which a rotor of the motor is stopped, excites an excitation phase corresponding to a stop position of the rotor among the plurality of the excitation phases, and measures a physical quantity which changes in accordance with an inductance of at least one of a plurality of coils configuring the plurality of excitation phases. The motor control apparatus estimates a temperature of the rotor from a measurement value of the measured physical quantity, and decides a parameter value for control of the motor based on the estimated temperature.