Patent application number | Description | Published |
20100172161 | SYSTEMS AND METHODS FOR COMMON-MODE VOLTAGE REDUCTION IN AC DRIVES - Control systems, methods and power conversion systems are presented for controlling common mode voltages in AC motor loads driven by inverter PWM control using switching sequences with only active vectors where a first vector of each switching sequence differs by one phase switching state from a last vector of a switching sequence of an adjacent sector, along with enhanced deadtime compensation and reflected wave reduction techniques in providing pulse width modulated switching signals to a switching inverter. | 07-08-2010 |
20100172162 | SYSTEMS AND METHODS FOR COMMON-MODE VOLTAGE REDUCTION IN FULLY REGENERATIVE AC DRIVES - Control systems, methods and fully regenerative power conversion systems are presented for mitigating common mode voltages in AC loads by employing inverter and/or active rectifier PWM control using switching sequences with only active vectors where a first vector of each switching sequence differs by one phase switching state from a last vector of a switching sequence of an adjacent sector. | 07-08-2010 |
20120187883 | CHOKE WITH CURRENT SENSOR - The present invention relates generally to systems and methods for detecting ground faults (i.e., line-to-ground faults) in motor drive systems. In particular, the embodiments described herein include a common mode choke of a motor drive system having additional (i.e., secondary) turns wound around a core of the common mode choke. These secondary turns are in addition to and separate from a plurality of sets of primary turns wound around the core of the common mode choke, each set of primary turns corresponding to a phase of AC power to which the common mode choke is directly coupled. The secondary turns terminate in series with a burden resistor. Ground faults may be detected by monitoring the voltage across the burden resistor. More specifically, the embodiments described herein include a controller including program instructions for receiving signals indicative of the voltage across the burden resistor, and for monitoring the voltage across the burden resistor to determine when ground faults occur in the motor drive system. | 07-26-2012 |
20120212172 | MODULAR LINE-TO-GROUND FAULT IDENTIFICATION - The present invention relates generally to systems and methods for detecting ground faults (i.e., line-to-ground faults) in electrical power conversion systems. In particular, the embodiments described herein include a common mode voltage booster module configured to calculate a common mode voltage boost factor and a common mode voltage boost function based on a plurality of voltage commands for the system. The common mode voltage boost factor and/or the common mode voltage boost function may be applied to the voltage commands to generate boosted voltage commands which, when applied to an inverter or converter, source current indicative of ground faults in the system. More specifically, the common mode voltage boost factor may be multiplied by a common mode voltage calculated by a common mode voltage calculator and summed with the voltage commands. In addition, the common mode voltage boost function may be summed with the voltage commands after the voltage commands have been summed with the common mode voltage boost factor. | 08-23-2012 |
20130119901 | System for Managing DC Link Switching Harmonics - 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. | 05-16-2013 |
20130119902 | System and Method for Managing DC Link Switching Harmonics - 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. | 05-16-2013 |
20140104896 | REGENERATIVE VOLTAGE DOUBLER RECTIFIER, VOLTAGE SAG/SWELL CORRECTION APPARATUS AND OPERATING METHODS - Single and multiphase regenerative voltage doubler rectifiers, sag/swell corrector apparatus, and operating methods are presented in which rectifier switching devices are selectively pulse width modulated for regenerative load conditions and for regenerating power during input voltage swell circumstances. | 04-17-2014 |
20140285120 | System and Method for Managing DC Link Switching Harmonics - 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. | 09-25-2014 |