In a control apparatus for a rotary electric machine, a first manipulation unit manipulates, as control for a predetermined first region with respect to the controlled variable, a voltage phase of a voltage vector applied to an armature winding while controlling a field current to cause a deviation between an amplitude of an induced voltage and an amplitude of a predetermined voltage to be equal to or smaller than a predetermined value, the induced voltage being generated in the armature winding based on rotation of the rotor, the predetermined voltage being applied to the armature winding; A second manipulation unit that manipulates, as control for a second region that is larger than the first region, the field current such that the controlled variable is controlled to the target value.

An electric machine includes a stator defining multiple stator poles with associated stator windings configured to receive a stator current. The electric machine also includes a rotor defining multiple fixed rotor poles with associated rotor windings, wherein the rotor defines a field energizable by magnetic fields produced by the stator windings when receiving the stator current to produce relative motion between the rotor and the stator and wherein the rotor is maintained in synchronicity with the magnetic fields produced by the stator during operation of the electric machine. The electric machine also includes a rectification system configured control against an alternating current being induced in the rotor poles as the field is energized by magnetic fields produced by the stator windings when receiving the stator current.

An electric machine includes a stator defining multiple stator poles with associated stator windings configured to receive a stator current. The electric machine also includes a rotor defining multiple fixed rotor poles with associated rotor windings, wherein the rotor defines a field energizable by magnetic fields produced by the stator windings when receiving the stator current to produce relative motion between the rotor and the stator and wherein the rotor is maintained in synchronicity with the magnetic fields produced by the stator during operation of the electric machine. The electric machine also includes a rectification system configured control against an alternating current being induced in the rotor poles as the field is energized by magnetic fields produced by the stator windings when receiving the stator current.

An electric machine includes a stator having a stator winding disposed thereon. A rotor is electromagnetically exposed to the stator. A field winding and an induction winding are disposed on the rotor. A rectifier is electrically coupled to the induction winding and the field winding. Upon application of a voltage to the stator winding, the stator winding produces a first rotating magnetic field and a second rotating magnetic field that has a different spatial frequency than the first rotating magnetic field. The first rotating magnetic field interacts asynchronously with the induction winding to produce an alternating current in the induction winding. The rectifier changes the alternating current to a direct current that is supplied to the field winding. The field winding interacts synchronously with the second rotating magnetic field.

An electric drive system is connected to a power battery pack to drive a motor, the motor includes an exciting winding, and the electric drive system includes a bus, a three-level inverter circuit, an electric excitation circuit, and a controller. The bus includes a positive bus and a negative bus. The three-level inverter circuit includes a first bus capacitor and a second bus capacitor. The first bus capacitor is connected between the positive bus and a bus midpoint, and the second bus capacitor is connected between the negative bus and the bus midpoint. A first input terminal of the electric excitation circuit is connected in parallel to the first bus capacitor, a second input terminal of the electric excitation circuit is connected in parallel to the second bus capacitor, and an output terminal of the electric excitation circuit is connected to the exciting winding of the motor.

An electric machine includes a stator defining multiple stator poles with associated stator windings configured to receive a stator current. The electric machine also includes a rotor defining multiple fixed rotor poles with associated rotor windings, wherein the rotor defines a field energizable by magnetic fields produced by the stator windings when receiving the stator current to produce relative motion between the rotor and the stator and wherein the rotor is maintained in synchronicity with the magnetic fields produced by the stator during operation of the electric machine. The electric machine also includes a rectification system configured control against an alternating current being induced in the rotor poles as the field is energized by magnetic fields produced by the stator windings when receiving the stator current.

An electric machine includes a stator and a rotor energizable by magnetic fields produced by the stator when receiving a stator current to produce relative motion between the rotor and the stator. A controller is configured to send the stator current through the stator at a current angle measured from the closest one of a pole of the rotor, determine a desired operational output of the electric machine, and determine a desired rotor motion corresponding to the desired operational output of the electric machine. The controller is further configured to calculate a vector control modulation applied to the stator that elicits the desired rotor motion, and adjust the current angle of the stator current based on the vector control modulation to cause the rotor to perform the desired rotor motion and achieve the desired operational output of the electric machine.

In accordance with at least one aspect of this disclosure, a method can include measuring a voltage across a DC link of a generator system when a generator exciter is inactive and a generator permanent magnet is active, and detecting a short or open permanent magnet generator (SOPMG) fault condition in the generator system with a DC link monitor operatively connected to measure the voltage across the DC link.

A rotary electrical machine includes a switch for supplying power to a field winding and a controller. A ratio of an on-time to a switching cycle of the switch, i.e., a duty ratio which is larger than the duty ratio corresponding to the field current that gives the maximum reduction amount of the inductance of the field winding with respect to an increasing amount of the field current in a range that the field current can take and which has a predetermined value less than 100%. The controller calculates the duty ratio on the condition that an upper limit of the duty ratio is set as the predetermined value and turns on/off the switch based on the calculated duty ratio, and sets the predetermined value to be larger as a rotation speed of a rotor is higher, or as a d-axis current flowing through an armature winding is larger.

Various embodiments include a system having: at least one computing device configured to monitor a dynamoelectric machine having a rotor including an exciter electrically coupled with a field winding, by performing actions including: obtaining measured data indicating a resistance of the field winding at a plurality of rotor angular positions while the rotor is rotating at a speed below one-hundred revolutions per minute; comparing the measured data indicating the resistance of the field winding at the plurality of rotor angular positions with a threshold resistance range; and indicating a potential fault in the field winding in response to determining the measured data indicating the resistance deviates from the threshold resistance range.