A drive system includes a drive device including an electric power generator; a fuel cell; a secondary battery; a fuel cell step-up converter including a diode; a relay connected to wiring between the fuel cell step-up converter and the drive device; a secondary battery step-up converter connected; a fuel cell voltage sensor; a secondary battery voltage sensor; and a controller. The controller stops the secondary battery step-up converter when a short-circuit fault of the diode is detected, disconnects the relay when a voltage of the fuel cell is higher than a voltage of the secondary battery after stopping the secondary battery step-up converter, and when the voltage of the secondary battery is higher than or equal to the voltage of the fuel cell, executes a voltage control process which increases the voltage of the fuel cell relative to the voltage of the secondary battery, and disconnects the relay.

A rotor for an LSIPM comprises a plurality of permanent magnets defining a number of poles (P) of the LSIPM, and a plurality of rotor bars spaced about the rotor defining a rotor bar area (BA). The rotor bars are formed of a conductive material having an associated conductivity (?.sub.RB). End members are disposed on axial opposite ends of the rotor core. The end members are in electrical contact with the rotor bars. The end members are formed from a material having an associated conductivity (?.sub.EM). Each end ring member has a minimum geometric cross sectional area (ERA) and outer diameter that generally corresponds to the rotor core outer diameter. The ERA is greater than 0.5 times the rotor bar area per the number of poles (BA/P) times a ratio of the rotor bar material conductivity to the end member material conductivity (?.sub.RB/?.sub.EM).

A rotor for an LSIPM comprises a plurality of permanent magnets defining a number of poles (P) of the LSIPM, and a plurality of rotor bars spaced about the rotor defining a rotor bar area (BA). The rotor bars are formed of a conductive material having an associated conductivity (?.sub.RB). End members are disposed on axial opposite ends of the rotor core. The end members are in electrical contact with the rotor bars. The end members are formed from a material having an associated conductivity (?.sub.EM). Each end ring member has a minimum geometric cross sectional area (ERA) and outer diameter that generally corresponds to the rotor core outer diameter. The ERA is greater than 0.5 times the rotor bar area per the number of poles (BA/P) times a ratio of the rotor bar material conductivity to the end member material conductivity (?.sub.RB/?.sub.EM).

A field winding type synchronous motor includes an exciter 4 and, after starting by forming a short circuit of a field winding 10, excites the field winding by using the exciter, and includes a starting control circuit 30 that outputs a control signal controlling On/Off of a first opening/closing device, in which the exciter and the field winding are connected through the first opening/closing device 1. The starting control circuit includes: a signal transmitting circuit that outputs the control signal at timing, which is detected based on an induced electromotive voltage generated in the field winding, at which switching to a synchronous operation is performed; and a time limit setting circuit that, after a predetermined time elapses after the starting control circuit is started, directs the signal transmitting circuit to output the control signal.

A field winding type synchronous motor includes an exciter 4 and, after starting by forming a short circuit of a field winding 10, excites the field winding by using the exciter, and includes a starting control circuit 30 that outputs a control signal controlling On/Off of a first opening/closing device, in which the exciter and the field winding are connected through the first opening/closing device 1. The starting control circuit includes: a signal transmitting circuit that outputs the control signal at timing, which is detected based on an induced electromotive voltage generated in the field winding, at which switching to a synchronous operation is performed; and a time limit setting circuit that, after a predetermined time elapses after the starting control circuit is started, directs the signal transmitting circuit to output the control signal.

Monitoring conditions of an electric motor using stator current and voltage signals from power supplied to the motor is disclosed herein. The stator voltage and current signals may be used to calculate instantaneous power values which may be used to calculate slip. The slip may be used to monitor for a locked rotor condition during startup of the motor. The slip value may be used to provide thermal protection to the electric motor.

Monitoring conditions of an electric motor using stator current and voltage signals from power supplied to the motor is disclosed herein. The stator voltage and current signals may be used to calculate instantaneous power values which may be used to calculate slip. The slip may be used to monitor for a locked rotor condition during startup of the motor. The slip value may be used to provide thermal protection to the electric motor.

A brushless starter-generator system is contained within a single housing. The housing has a first end with an opening to receive a drive spline from a motive source and an opposing second end. A brushless, rotating, machine is located adjacent the first end and is kinetically connectable to the drive spline. A power control unit is adjacent the second end and electrically coupled to the brushless, rotating machine. The brushless, rotating machine is selected from the group consisting of a synchronous machine, a permanent magnet machine, and an induction machine. Electrical and mechanical interfaces are identical to a like-rated brushed version for a true drop-in replacement capability to facilitate replacements and up-grades

In a variable speed generator-motor apparatus, a power converter includes six two-terminal arms each formed by serially connecting k unit converters that can output arbitrary voltage, an AC rotating electric machine includes an armature winding with 60-degree phase zone formed from a double layer coil, the armature winding being divided into first and second pole sides to form double star connection by binding neutral points and to be drawn out as two sets of three-phase terminals; three-phase terminals on the first pole side are connected to first terminals of three arms, and second terminals of the three arms are star-connected to a first terminal of a DC power supply; three-phase terminals on the second pole side are connected to second terminals of remaining three arms, and first terminals of the three arms are star-connected to a second terminal of the DC power supply.

A field winding type synchronous machine has a stator having a stator core to which a stator coil is wound, and a rotor that rotates while facing a peripheral surface of the stator with an electromagnetic gap therebetween. The rotor includes a rotor core having a plurality of main pole portions and interpole portions, main pole windings wound around the main pole portions, interpole windings wound around the interpole portions, and a full-wave rectifier circuit for energizing the field current to the main pole windings. The interpole windings produce the induced current by a magnetic flux generated by a time harmonic current superimposed on a fundamental wave of the stator coil. The electromagnetic gaps between the interpole portions and a circumferential surface of the stator are configured larger than electromagnetic between the main pole portions and the circumferential surface of the stator.