Abstract: An electromagnetic stimulator circuit has a precharge power supply, a capacitor, a set of switches, and a stimulator coil. The switches, which can be implemented using a variety of devices, enable flexible control over the coil current waveform without requiring the physical reconfiguration of circuit elements. The shape of the output current pulse is controlled by the modulation of the switches, and much of the energy applied to the coil is returned from the coil to the capacitor for reuse on the succeeding pulse. Less power is required and less heat energy is generated.

Abstract: An electromagnetic stimulator circuit has a pre-charge power supply, a capacitor, a set of switches, and a stimulator coil. The switches, which can be implemented using a variety of devices, enable flexible control over the coil current waveform without requiring the physical reconfiguration of circuit elements. The shape of the output current pulse is controlled by the modulation of the switches, and much of the energy applied to the coil is returned from the coil to the capacitor for reuse on the succeeding pulse. Less power is required and less heat energy is generated.

Abstract: An alternator system having an alternating current voltage source includes a rectifier coupled to the voltage source, a sensor coupled to the voltage source and an engine and a control circuit coupled to the voltage source, the rectifier and the sensor. The control circuit provides control signals to the rectifier and the voltage source. The alternator system further includes a fault protection controller coupled to an output of the alternator system and coupled to the control circuit. The rectifier operates such that the alternator system provides a load match which results in output power levels which are relatively high compared with output power levels of conventional alternator systems and the fault protection controller operates under fault conditions (e.g. load dump), and overrides the other controllers in the alternator system based on output voltage when a load dump occurs.

Abstract: A system for charging a first source from a second source includes an alternating current (ac) voltage source having an internal inductance, a switching power converter coupled to the ac voltage source and the first source, a control circuit coupled to the switching power converter, a connecting system for selectively connecting a positive terminal of the second source to the ac voltage source and a jump charging controller coupled to the control circuit and operative to enable the switching power converter to be used in conjunction with the ac voltage source inductances as a dc/dc converter to charge the first source from the second source.

Abstract: An alternator system having an alternating current (ac) voltage source includes a switched-mode rectifier (SMR) coupled to the ac voltage source and having an output port coupled to an output of the alternator system, and a controller coupled to said switched-mode rectifier so as to provide a controlled pulse sequence synchronized with an angular rotor position of the (ac) voltage source to activate and deactivate the switched-mode rectifier. The controller further includes a PWM generator having a first input to receive a total duty ratio signal synchronized with an angular rotor position of the (ac) voltage source. The switched mode rectifiers are controlled to increase power output levels at lower speeds near idle. The controller combines improved idle speed power output levels with load matching improvements from PWM control for more efficient operation when compared to circuits using conventional control or PWM load matching control alone.

Abstract: An alternator system having an ac machine includes a switched-mode rectifier operating at a duty cycle selected based upon at least one of the emf, frequency or speed of operation of the ac machine. The switched-mode rectifier operates such that the alternator system provides a load match which results in output power levels which are relatively high compared with output power levels of conventional alternator systems.

Abstract: A dual output alternator system includes an alternating current (ac) voltage source controllable by controlling a field current, a rectifier coupled to the ac voltage source and having first and second outputs coupled to respective ones of first and second outputs of the dual output alternator system, a sensor coupled to at least one of the ac voltage source, an engine and a back emf signal source and a control system having a first input coupled to an output of the sensor, a second input coupled to at least one of the first and second outputs of the dual output alternator system and a first output coupled to the rectifier.

Abstract: Markov chain controlled random modulation of switching signal sequences of for a power converter. The control is implemented in a power converter having an energy storage device which receives an input power from a source and provides an output power to a load. The converter includes a switching device for coupling the input power source to the energy storage device or coupling the storage device to the load in response to receiving a sequence of control signals generated from a control signal generator.

Abstract: A wire guide for EDM machining apparatus comprises a vacuum hot pressed titanium diboride block having a groove on a curved side of the block for positioning EDM wire. The block has a mounting hole therethrough lined with an electrically insulating sleeve.