Abstract: A system for distributing DC bus voltage and control power to multiple motors includes a rectifier front end supplying a DC bus voltage and a DC control voltage. Both the DC bus voltage and the DC control voltage are distributed via a common set of conductors. Diodes are operatively connected between the DC control voltage and the common set of conductors. The diodes allow forward conduction of the DC control voltage and distribution of control power to distributed devices when the DC bus voltage is not present. Once the DC bus voltage is present, the diodes block conduction of the DC control voltage. Each of the distributed devices are configured with an internal power supply that is operative to generate an internal control voltage from either the DC control voltage or the DC bus voltage.

Abstract: A system for distributing DC bus voltage and control power to multiple motors includes a rectifier front end supplying a DC bus voltage and a DC control voltage. Both the DC bus voltage and the DC control voltage are distributed via a common set of conductors. Diodes are operatively connected between the DC control voltage and the common set of conductors. The diodes allow forward conduction of the DC control voltage and distribution of control power to distributed devices when the DC bus voltage is not present. Once the DC bus voltage is present, the diodes block conduction of the DC control voltage. Each of the distributed devices are configured with an internal power supply that is operative to generate an internal control voltage from either the DC control voltage or the DC bus voltage.

Abstract: A system for distributing DC bus voltage and control power to multiple motors includes a rectifier front end supplying a DC bus voltage and a DC control voltage. Both the DC bus voltage and the DC, control voltage are distributed via a common set of conductors. Diodes are operatively connected between the DC control voltage and the common set of conductors. The diodes allow forward conduction of the DC control voltage and distribution of control power to distributed devices when the DC bus voltage is not present. Once the DC bus voltage is present, the diodes block conduction of the DC control voltage. Each of the distributed devices are configured with an internal power supply that is operative to generate an internal control voltage from either the DC control voltage or the DC bus voltage.

Abstract: A system for distributing DC bus voltage and control power to multiple motors includes a rectifier front end supplying a DC bus voltage and a DC control voltage. Both the DC bus voltage and the DC, control voltage are distributed via a common set of conductors. Diodes are operatively connected between the DC control voltage and the common set of conductors. The diodes allow forward conduction of the DC control voltage and distribution of control power to distributed devices when the DC bus voltage is not present. Once the DC bus voltage is present, the diodes block conduction of the DC control voltage. Each of the distributed devices are configured with an internal power supply that is operative to generate an internal control voltage from either the DC control voltage or the DC bus voltage.

Abstract: A system to detect a ground fault at the output of an inverter section prior to powering up a motor drive system is disclosed. A low voltage power supply is connected to the DC bus prior to connecting the input power source to the rectifier section. If a ground fault exists, the voltage potential on the DC bus causes conduction through one of the freewheeling diodes connected in parallel to the power switching device on the output of the inverter section. A fault detection circuit generates a signal corresponding to the presence of the low voltage potential when the low voltage is applied to the DC bus. If a ground fault is present at the output of one of the inverter sections, the motor drive system prevents the AC voltage from being applied to the rectifier section.

Abstract: A system to detect a ground fault at the output of an inverter section prior to powering up a motor drive system is disclosed. A low voltage power supply is connected to the DC bus prior to connecting the input power source to the rectifier section. If a ground fault exists, the voltage potential on the DC bus causes conduction through one of the freewheeling diodes connected in parallel to the power switching device on the output of the inverter section. A fault detection circuit generates a signal corresponding to the presence of the low Voltage potential when the low voltage is applied to the DC bus. If a ground fault is present at the output of one of the inverter sections, the motor drive system prevents the AC voltage from being applied to the rectifier section.

Abstract: A system configured to reduce the amplitude of reactive current present on a DC bus shared by multiple inverters is disclosed. The start of the switching period for the modulation routines of each inverter is synchronized, and a carrier phase angle is determined for a carrier signal within each of the inverters. The modulation routine of each inverter generates a reactive current on the shared DC bus. By controlling the carrier phase angle for each inverter, the reactive current of a first inverter may be generated at a phase angle that is offset from the phase angle of the reactive current generated by a second inverter. As a result, the reactive current from the first inverter cancels at least a portion of the reactive current from the second inverter, reducing the total reactive current present on the DC bus.

Abstract: A distributed motor drive system includes a power management module and multiple inverter modules integrated with the motors and located on a machine or process remote from the power management module. The power management module distributes DC voltage and command signals to each of the inverters, where the DC voltage is distributed between modules via a DC link cable. The integrated inverters execute switching routines to convert the DC voltage to an AC voltage suitable for controlling the motor. Each of the power management module and the inverters includes a portion of the DC bus. The current on the DC link cable is monitored and general bus utilization as well as overload conditions are reported.

Abstract: A system configured to reduce the amplitude of reactive current present on a DC bus shared by multiple inverters is disclosed. The start of the switching period for the modulation routines of each inverter is synchronized, and a carrier phase angle is determined for a carrier signal within each of the inverters. The modulation routine of each inverter generates a reactive current on the shared DC bus. By controlling the carrier phase angle for each inverter, the reactive current of a first inverter may be generated at a phase angle that is offset from the phase angle of the reactive current generated by a second inverter. As a result, the reactive current from the first inverter cancels at least a portion of the reactive current from the second inverter, reducing the total reactive current present on the DC bus.

Abstract: A distributed motor drive system includes a power management module and multiple inverter modules integrated with the motors and located on a machine or process remote from the power management module. The power management module distributes DC voltage and command signals to each of the inverters. The DC voltage is distributed between modules via a DC link cable. The integrated inverters execute switching routines to convert the DC voltage to an AC voltage suitable for controlling the motor. Each of the power management module and the inverters includes a portion of the DC bus capacitance. The distributed motor drive system also includes a link inductance between the power management module and the inverters to limit the amount of reactive current generated by the inverters.

Abstract: A distributed motor drive system includes a power management module and multiple inverter modules integrated with the motors and located on a machine or process remote from the power management module. The power management module distributes DC voltage and command signals to each of the inverters, where the DC voltage is distributed between modules via a DC link cable. The integrated inverters execute switching routines to convert the DC voltage to an AC voltage suitable for controlling the motor. Each of the power management module and the inverters includes a portion of the DC bus. The current on the DC link cable is monitored and general bus utilization as well as overload conditions are reported.

Abstract: A distributed motor drive system includes a power management module and multiple inverter modules integrated with the motors and located on a machine or process remote from the power management module. The power management module distributes DC voltage and command signals to each of the inverters, where the DC voltage is distributed between modules via a DC link cable. The integrated inverters execute switching routines to convert the DC voltage to an AC voltage suitable for controlling the motor. Each of the power management module and the inverters includes a portion of the DC bus. The current on the DC link cable is monitored and general bus utilization as well as overload conditions are reported.

Abstract: A distributed motor drive system includes a power management module and multiple inverter modules integrated with the motors and located on a machine or process remote from the power management module. The power management module distributes DC voltage and command signals to each of the inverters, where the DC voltage is distributed between modules via a DC link cable. The integrated inverters execute switching routines to convert the DC voltage to an AC voltage suitable for controlling the motor. Each of the power management module and the inverters includes a portion of the DC bus. The current on the DC link cable is monitored and general bus utilization as well as overload conditions are reported.

Abstract: A distributed motor drive system includes a power management module and multiple inverter modules integrated with the motors and located on a machine or process remote from the power management module. The power management module distributes DC voltage and command signals to each of the inverters. The DC voltage is distributed between modules via a DC link cable. The integrated inverters execute switching routines to convert the DC voltage to an AC voltage suitable for controlling the motor. Each of the power management module and the inverters includes a portion of the DC bus capacitance. The distributed motor drive system also includes a link inductance between the power management module and the inverters to limit the amount of reactive current generated by the inverters.