Abstract: A direct current to alternating current converter method and apparatus is disclosed that may comprise a direct current (DC) input source; an alternating current (AC) output inverter circuit, having an input connected across the DC input source; a partial power DC-DC boosting circuit intermediate to the DC input source and the DC input of the inverter stage, configured to increase the input voltage of the DC input source whenever the input voltage falls below a minimum required to synthesize an output waveform of a selected shape and a partial power DC-DC boosting circuit intermediate to the DC input source and the DC input of the inverter stage, configured to increase the input voltage of the DC input source during higher amplitude portions of inverter circuit output voltage waveform.

Abstract: A system and method are provided for determining the position of a vehicle on a guideway. For operation, the vehicle carries a magnetic array having a wavelength “?”. Further, the guideway includes a propulsion winding for carrying a propulsion current. Also, the guideway is provided with a position winding that has the same wavelength “?” and includes two helical wires that are displaced from each other by “?/4”. Importantly, a transmitter is located on the vehicle for emitting a position current that interacts with the position winding to generate a return signal from each helical wire. Also, the system includes a processor for receiving and evaluating the return signals to determine the position of the vehicle on the guideway. As a result, the determined position is used to maximize the interaction of the propulsion current with the magnetic array for propulsion of the vehicle.

Abstract: A system and method are provided for determining the position of a vehicle on a guideway. For operation, the vehicle includes a magnet system having a wavelength “?”. Further, the guideway includes a propulsion winding for carrying a propulsion current. Structurally, the propulsion winding includes a series of sections, with each section having a wavelength “?”. Further, the propulsion winding includes “N” coils linearly aligned along the guideway, with a phase difference of “?/N” between adjacent coils. Importantly, a transmitter is located on the vehicle for emitting a position current that interacts with the propulsion winding to produce a signal in each coil. Also, the system includes a trap connected to each coil for receiving each respective signal, and a processor for resolving the respective signals to determine the position of the vehicle on the guideway.

Abstract: A system and method are provided for determining the position of a vehicle on a guideway. For operation, the vehicle carries a magnetic array having a wavelength “?”. Further, the guideway includes a propulsion winding for carrying a propulsion current. Also, the guideway is provided with a position winding that has the same wavelength “?” and includes two helical wires that are displaced from each other by “?/4”. Importantly, a transmitter is located on the vehicle for emitting a position current that interacts with the position winding to generate a return signal from each helical wire. Also, the system includes a processor for receiving and evaluating the return signals to determine the position of the vehicle on the guideway. As a result, the determined position is used to maximize the interaction of the propulsion current with the magnetic array for propulsion of the vehicle.

Abstract: A system and method are provided for determining the position of a vehicle on a guideway. For operation, the vehicle includes a magnet system having a wavelength “?”. Further, the guideway includes a propulsion winding for carrying a propulsion current. Structurally, the propulsion winding includes a series of sections, with each section having a wavelength “?”. Further, the propulsion winding includes “N” coils linearly aligned along the guideway, with a phase difference of “?/N” between adjacent coils. Importantly, a transmitter is located on the vehicle for emitting a position current that interacts with the propulsion winding to produce a signal in each coil. Also, the system includes a trap connected to each coil for receiving each respective signal, and a processor for resolving the respective signals to determine the position of the vehicle on the guideway.

Abstract: Devices and systems that use an adaptively limited PWM duty-cycle to control a circuit and methods and control programs to operate and to control the devices and systems to adaptively limit the PWM duty-cycle are disclosed. The devices and systems are capable of adjusting the duty-cycle such that the actual inductor current in the next cycle is precisely limited. Specifically, a maximum allowable duty-cycle for time interval N+1 is estimated during time interval N. When the duty-cycle is applied to the circuit at time interval N+1, the peak inductor current is kept below a maximum allowable inductor current level.