Abstract: The throttle of an engine in an engine driven generator system operating under an intermittently heavy load, as in supplying current to a welder, is controlled such that successive control signals sent to a throttle actuator for adjusting the engine throttle position are inhibited until at least a predetermined time has elapsed since the last preceding adjustment to the throttle. This procedure ensures that, as to each incremental adjustment to the throttle, the engine has sufficient time to respond, thereby preventing over-speeding or stalling the engine. The throttle actuator may be a stepper motor which is stepped by throttle position change signals from a processor which monitors engine speed and generator load to determine whether the throttle should be adjusted and, if so, in which direct. Alternatively, the throttle actuator may be a solenoid pulling against a spring in accordance with the average current through the solenoid coil.

Abstract: The throttle of an engine in an engine driven generator system operating subject to a wide and rapidly variable load, as in supplying current to a welder, is operated such that control signals are sent to a throttle actuator for adjusting the engine throttle position in response to load changes. The throttle actuator may be a solenoid pulling against a spring in accordance with the average current through the solenoid coil. In this embodiment, the processor causes pulse width modulated signals to be applied across the solenoid coil with throttle position changes being reflected in changes to the width of the pulses, such changes in the pulse width being delayed for at least the predetermined time since the last preceding adjustment to the throttle.

Abstract: A lightweight engine-driven generator set including a stator having at least first and second windings (preferably three-phase) and a rotor having a soft magnetic core and a plurality of high energy product permanent magnets, separated by consequence poles, disposed proximate the stator such that relative motion of the rotor and stator causes magnetic flux from the rotor to interact with and induce current in the stator windings. The first winding includes a predetermined number of turns corresponding to a first predetermined voltage output; and the second winding includes a predetermined number of turns corresponding to a second predetermined voltage output, the respective windings being grouped together as a unit and wound about the core such that the respective winding coils are wound in continuous close thermal contact with each other.

Abstract: A particularly advantageous power converter, suitable for use in an engine powered generator system. A signal simulating a desired AC waveform is produced by a converter circuit at first and second converter output terminals. The converter circuit, responsive to respective switching signals applied thereto, selectively effects current paths between a juncture node and one of the first and second converter output terminals and between a common rail and the other of the first and second converter output terminals. A controller selectively generates control signals to the converter circuit and to a mechanism for varying the magnitude of the juncture node voltage, to create a predetermined waveform at the converter output terminals simulating the desired AC waveform. A number of alternative embodiments for producing a simulated sine wave are described, as well as accommodations for inductive loads, and mechanisms for minimizing power dissipation during the switching interval.

Abstract: An improved method and system of increasing the effective electrical load capacity of a power converter is disclosed. Potential damage due to current surges from variation in load is avoided by sensing an impending over-current condition, decreasing the system output by a predetermined amount or to a predetermined level, and then gradually increasing the output to bring the system back to desired operating conditions. Such control can be affected by varying the throttle setting to adjust rotor speed, controlling the DC rail level, or a combination of both methods.

Abstract: A particularly advantageous power converter, suitable for use in an engine powered generator system. A signal simulating a desired AC waveform is produced by a converter circuit at first and second converter output terminals. The converter circuit, responsive to respective switching signals applied thereto, selectively effects current paths between a juncture node and one of the first and second converter output terminals and between a common rail and the other of the first and second converter output terminals. A controller selectively generates control signals to the converter circuit and to a mechanism for varying the magnitude of the juncture node voltage, to create a predetermined waveform at the converter output terminals simulating the desired AC waveform. A number of alternative embodiments for producing a simulated sine wave are described, as well as accommodations for inductive loads, and mechanisms for minimizing power dissipation during the switching interval.