Abstract: For starting a rotatable 3-phase a-c electrical machine of the synchronous type, the stator windings of the machine are connected to an electric storage battery via a controllable electric power converter, and the d-c field winding is connected in series with the stator windings by inserting it in the load current path between the converter and battery. Field weakening resistance is connected in parallel with the field winding. The converter includes a plurality of electric valves (thyristors) that are cyclically turned on in a predetermined sequence in synchronism with alternating voltages developed at the line terminals of the stator windings.

Abstract: A high-energy, high-current homopolar generator pulsed power supply system that is compact and field portable. The power supply system includes a hompolar generator (HPG), an auxiliary supply and drive system, both mounted on a skid frame, and a control system coupled to the HPG and drive system. The homopolar generator has a split rotor with insulation between the halves and a recess in the periphery. A stator ring and field coil, for producing a magnetic field through which the rotor halves make two simultaneous voltage-generating passes, are disposed within the recess in the rotor. Air-actuated brush mechanisms inside and outside the recess contact surfaces of the rotor and collect discharge current. The auxiliary supply and drive system includes a motoring system comprising hydraulic motors for driving the HPG to speed, a bearing lubrication system, a generator for energizing the field coil, and a brush actuator air supply system, all of which are driven by a prime mover.

Abstract: A mobile X-ray apparatus (20) is disclosed which incorporates a power supply (22) in which the energy for operation of the X-ray tube (21) is supplied from a flywheel (50) coupled to an electrical machine (24) which functions as both a motor and generator. In the motor mode of operation, a controller (21) provides power to the machine (24) to operate it as a motor and drive the flywheel up to a desired operating speed. Upon request of the operator to initiate an exposure, the controller power is disconnected from the machine and the power terminals (32) of the machine (24) are connected to a transformer and rectifier (27) which increases the generated voltage and rectifies it to provide the high voltage across the X-ray tube (21) required for proper exposures.

Abstract: A power conversion system for converting between electric and motive power may be utilized either in a generating mode to generate electric power from motive power supplied by a prime mover or in a starting mode wherein motive power is developed by the power conversion system from electrical power and is supplied through a torque converter to the prime mover to start same. The power conversion system includes a main generator, an exciter and a permanent magnet generator, or PMG, which together comprise a brushless alternator. When operated in the starting mode, power is supplied to the PMG to cause it to act as a motor and thereby drive a rotor which is common to the PMG, exciter and main generator. Once a predetermined operating condition of the generator is attained, the main generator is supplied power from a motor control to cause the generator to act as a synchronous motor and the power supply to the PMG is disconnected.

Abstract: A method and system for delaying mechanical loading of an internal combustion engine by an alternator during start-up and transitional phases of the engine by inhibiting the field winding current of the alternator until the engine reaches a predetermined operational condition for a continuous predetermined period of time.

Abstract: The same electrical machine geared to the fly-wheel of a vehicle engine serves as the starter and as the generator. This machine is excited by permanent magnets on a rotor and its stator is wound with two phase windings offset from each other by 90.degree. electrical. Half-bridge rectifiers are utilized in a circuit cooperating with the center tap of each winding for charging the battery in generator operation, cooperating with a unit including at least one MOSFET for regulating the charging current. In motor operation the winding center taps are connected to one pole of the battery and the common connection of the MOSFETs is connected to the other pole of the battery so that these devices can operate as d.c. to a.c. converter elements for providing pulses in proper sequence to the erstwhile generator to make it operate as a motor.

Abstract: A circuit for use with an induction generator. The circuit is arranged to initiate operation of the induction generator as a motor to bring the system up to operating speed and subsequently to rearrange the system automatically to cause the induction generator to operate in a generating mode. The automatic reconnection is effected as an incident of the motor reaching a preselected speed. Determination of the preselected speed may be effected by voltage responsive means in one form of the invention, and by centrifugal switch in another form of the invention. The control is effected by suitably selectively connecting the phase winding of the generator. In the illustrated embodiment, a starting capacitor and a power factor correction capacitor are automatically connected at proper times in the operation.

Abstract: This invention relates to electrical aircraft engine start and generating system for use in an aircraft having an engine driven torque converter coupled to an alternator which provides AC power for conversion to DC and AC power. The system includes a reversible AC to DC converter controllably electrically coupled to the alternator and a controller unit to provide DC power in a generating mode. The reversible AC to DC converter is capable of receiving externally supplied DC power to be converted to AC power to drive the alternator as a motor in a start mode. A DC to AC converter is controllably electrically coupled to the controller unit and the DC power output during the generating mode. The reversible DC to AC converter in the start mode is mutually controllably electrically coupled to the externally supplied DC power.

Abstract: Disclosed is an apparatus for carrying out normal stop of a synchronous generator in an advantageous manner without use of a field breaker. The apparatus comprises a six-phase thyristor converter for controlling field excitation of the synchronous generator in dependence upon terminal voltage thereof, which converter exhibits not only a forward conversion function (power rectifier) but also backward conversion function (power inverter). When a generator operation stop command is produced, the operation of the converter in power rectifier mode is changed over to power inverter mode.

Abstract: An automatic monitoring and recharging system adapted to continuously monitor the terminal voltage of a D.C. storage battery and, whenever the terminal voltage falls below a first preselected value, to automatically initiate an engine-driven A.C. generator which is utilized to recharge the storage battery. The recharging interval is terminated when the recharging current attains a second preselected value whereupon the system is automatically returned to a voltage monitoring status.The monitoring and recharging system of the present invention finds particular utility with respect to storage batteries used in association with recreational vehicles.