초록 ▼

A method and apparatus are provided for controlling the switching devices in a switched reluctance machine bridge inverter having at least two switching devices per phase. One switching device is used for hysteresis band current chopping to regulate phase current magnitude, while the other switching

A method and apparatus are provided for controlling the switching devices in a switched reluctance machine bridge inverter having at least two switching devices per phase. One switching device is used for hysteresis band current chopping to regulate phase current magnitude, while the other switching device, in combination with a flyback diode, provides a circulating path for phase current. Alternatively, current chopping and circulating are alternated between both switching devices during each conduction interval of the corresponding machine phase. Ripple current is decreased, thereby reducing the required size of the DC link capacitor. Switching losses are also reduced.

대표청구항 ▼

A control for a bridge inverter for driving a multiphase switched reluctance machine, said bridge inverter comprising a plurality of phase legs, each of said phase legs comprising an upper switching device and a lower switching device both connected in series with a machine phase winding of said swi

A control for a bridge inverter for driving a multiphase switched reluctance machine, said bridge inverter comprising a plurality of phase legs, each of said phase legs comprising an upper switching device and a lower switching device both connected in series with a machine phase winding of said switched reluctance machine, each of said phase legs further comprising an upper flyback diode coupled in parallel with the series combination of said upper switching device and said machine phase winding and a lower flyback diode coupled in parallel with the series combination of said lower switching device and said machine phase winding, respectively, the series combination of said upper and lower switching devices and said machine phase winding being adapted to be connected across an external DC source, said control comprising: a plurality of current sensing means, each respective one of said current sensing means being coupled to the corresponding inverter phase leg for producing a sense current representative of instantaneous phase current therethrough; commanded reference waveform generating means for providing a reference current waveform; a plurality of comparator means, each respective one of said comparator means being coupled to the corresponding current sensing means for comparing the respective sense current with said reference current waveform so as to generate a first logic level signal when the respective sense current exceeds said reference current waveform by a first predetermined amount and a second logic level signal when the respective sense current is less than said reference current waveform by a second predetermined amount; a plurality of first drive means, each respective one of said first drive means being coupled to the lower switching device of the corresponding phase leg for driving said lower switching device during each conduction interval thereof; and a plurality of second drive means, each respective one of said second drive means being coupled to the upper switching device of the corresponding phase leg for turning off said upper switching device of the corresponding phase leg whenever the respective sense current exceeds said reference current waveform by said first predetermined amount so as to allow the respective phase current to circulate through the respective machine phase winding while said upper switching device is nonconductive, and for turning back on said upper switching device of the corresponding phase leg during the conduction interval thereof when the respective phase current has decreased to a level where the respective sense current is less than said reference current waveform by said second predetermined amount.