Described is a method of aligning a rotor of a polyphase synchronous motor having a permanent magnet rotor to a predetermined, selected, or specified rotor angle. The method comprises sensing or measuring the stator winding voltages/currents during synchronous operation of the motor. Based on the sensed or measured stator winding voltages/currents, a synchronously rotating reference frame vector voltage (V.sub.q) in the q-axis is determined as a product of stator winding resistance (R.sub.s) and stator winding current (i.sub.q) in the q-axis. Corresponding polyphase drive voltages for the synchronous motor for the predetermined, selected, or specified rotor angle (?) are determined from the synchronously rotating reference frame vector voltage (V.sub.q). The polyphase drive voltages are applied to align the rotor on stopping at said predetermined, selected, or specified rotor angle (?). The polyphase drive voltages are applied by suitable PWM drive signals.

A circuit for controlling a motor that includes control circuitry configured to determine whether a commutation event has occurred for a first sector of a plurality of sectors of a cycle for the motor based on a first selected phase current signal and a second selected phase current signal. In response to a determination that the commutation event has occurred for the first sector, the control circuitry is configured to determine that the motor is operating in a second sector of the plurality of sectors of the cycle for the motor. The control circuitry is further configured to determine a second angle of stator voltage vector for the motor based on the determination that the motor is operating in the second sector and generate the control signal based on the second angle of stator voltage vector for the motor.

A circuit for controlling a motor that includes control circuitry configured to determine whether a commutation event has occurred for a first sector of a plurality of sectors of a cycle for the motor based on a first selected phase current signal and a second selected phase current signal. In response to a determination that the commutation event has occurred for the first sector, the control circuitry is configured to determine that the motor is operating in a second sector of the plurality of sectors of the cycle for the motor. The control circuitry is further configured to determine a second angle of stator voltage vector for the motor based on the determination that the motor is operating in the second sector and generate the control signal based on the second angle of stator voltage vector for the motor.

In accordance with at least one aspect of this disclosure, a system includes a generator controller configured to receive input from an AC power source, an exciter, and a generator, and output one or more signals to an exciter to control generation of generator output. The system also includes a rectifier controller configured to receive input from the generator controller, the exciter, and a rectifier, and output one or more control signals to the generator controller and the rectifier to control active rectification of the generator output.

A method and apparatus for detecting an initial position of a rotor of a motor includes: switching on or off respective switches in respective connecting branches connected to respective phase windings of the motor so as to obtain different switch state combinations capable of supporting different phase states of the motor, wherein the different switch state combinations support inputting voltages for different phases to the motor; for each switch state combination, injecting a voltage and recording a start time; monitoring respective phase currents of the motor, including: stopping the injecting of the voltage in response to determining that at least one of the respective phase currents is greater than a current threshold during the injecting of the voltage; and recording an end time in response to determining that the respective phase currents are all attenuated to zero after stopping the injecting of the voltage; and calculating a time difference between the end time and the start time; and determining the initial position of the rotor based on respective time differences in different switch state combinations.

A method and apparatus for detecting an initial position of a rotor of a motor includes: switching on or off respective switches in respective connecting branches connected to respective phase windings of the motor so as to obtain different switch state combinations capable of supporting different phase states of the motor, wherein the different switch state combinations support inputting voltages for different phases to the motor; for each switch state combination, injecting a voltage and recording a start time; monitoring respective phase currents of the motor, including: stopping the injecting of the voltage in response to determining that at least one of the respective phase currents is greater than a current threshold during the injecting of the voltage; and recording an end time in response to determining that the respective phase currents are all attenuated to zero after stopping the injecting of the voltage; and calculating a time difference between the end time and the start time; and determining the initial position of the rotor based on respective time differences in different switch state combinations.

An initial rotor position detection device based on a permanent-magnet synchronous motor, including a host computer, a real-time simulation system, and a control system, where the real-time simulation system is connected to the control system, for determining an encoder pulse signal according to the model parameter of the permanent-magnet synchronous motor, the model parameter of the inverter, and a PWM pulse wave generated by the control system; and the control system is connected to the real-time simulation system, for using a binary search algorithm to determine an initial rotor angle of the permanent-magnet synchronous motor according to the encoder pulse signal sent by the real-time simulation system. A comprehensive closed-loop test circuit can be achieved by setting a host computer, a real-time simulation system, and a control system, and a used binary search algorithm can effectively and quickly detect an initial rotor position of a permanent-magnet synchronous motor.

An initial rotor position detection device based on a permanent-magnet synchronous motor, including a host computer, a real-time simulation system, and a control system, where the real-time simulation system is connected to the control system, for determining an encoder pulse signal according to the model parameter of the permanent-magnet synchronous motor, the model parameter of the inverter, and a PWM pulse wave generated by the control system; and the control system is connected to the real-time simulation system, for using a binary search algorithm to determine an initial rotor angle of the permanent-magnet synchronous motor according to the encoder pulse signal sent by the real-time simulation system. A comprehensive closed-loop test circuit can be achieved by setting a host computer, a real-time simulation system, and a control system, and a used binary search algorithm can effectively and quickly detect an initial rotor position of a permanent-magnet synchronous motor.

A control device of a permanent magnet synchronous motor that is a control device of a sensorless-type permanent magnet synchronous motor in which a rotor using a permanent magnet rotates by a rotating magnetic field caused by a current flowing in an armature includes: a driver that applies a voltage to the armature and drives the rotor; an initial position estimator that estimates an initial position which is a magnetic pole position of the rotor that is stopped; and a controller that controls the driver so as to apply a pulse train including a voltage pulse for searching the initial position for each of n angle positions dividing a search range of an electrical angle of 360 degrees to the armature, wherein the pulse train includes a first pulse and a second pulse.

A magnetic pole position detection device of a motor control device includes a calculation unit to estimate a magnetic pole position. The calculation unit generates a voltage pulse command for three-phase connection to actuate all of three legs included in an inverter, and a voltage pulse command for one phase opened to actuate only two of the three legs, and narrows down the estimation range on the basis of a first magnetic pole position estimated value estimated on the basis of a motor current that flows during application of the voltage pulse command for three-phase connection, and a second magnetic pole position estimated value estimated on the basis of a motor current that flows during application of the voltage pulse command for one phase opened.