Abstract: A motor drive configured to be connected to an external device is provided. The motor drive includes an outer housing, a power module housed within the outer housing, and a control module housed within the outer housing and in communication with the power module. The motor drive also includes a communications port disposed on the outer housing and in communication with the control module. The communications port supports dual-role power in which the motor drive powers the external device when the external device is of a first type and the motor drive receives power from the external device when the external device is of a second type.

Abstract: A power supply system includes modular power supply modules interconnected via a wire harness. The power supply system can be installed in one or more electrical cabinets in a manufacturing facility, for example, among other possible applications. The wire harness includes a fault bus and a synchronization bus, and the individual power supply modules detect and report faults as well as synchronize operation, such as pre-charging, via communication using the wire harness.

Abstract: A power supply circuit for use with a power supply system. The power supply circuit can be provided within a power supply module connected with one or more additional power supply modules as part of the power supply system. The power supply circuit includes an optocoupler and a resistor ladder connected to the optocoupler. The circuit asserts a synchronization signal responsive to the optocoupler being energized.

Abstract: To avoid the catastrophic failure of a drive, protection circuitry is configured to limit current in the DC bus capacitors. The drive may include an isolation circuit and a protection circuit having a comparator. The protection circuit may be configured to compare the voltage measured across a DC bus capacitor with a threshold voltage and activate the isolation circuit when the DC capacitor voltage exceeds the threshold voltage. The drive may also include a low voltage circuit coupled to the isolation circuit, where the low voltage circuit is configured to interrupt the bypass signal to disengage the bypass circuit and activate the precharge circuit when the isolation circuit is activated. Accordingly, the current in the drive and to the DC bus capacitors is limited by the precharge circuit when the voltage of a capacitor in the DC bus exceeds a threshold.

Abstract: A power conversion system includes a sensing circuit to sense a system voltage of a DC bus circuit with a first DC bus terminal with a first voltage positive relative to a second voltage of a second DC bus terminal. The sensing circuit includes a first capacitor having a first terminal coupled to the second DC bus terminal, and a second terminal; a second capacitor having a first terminal coupled to the second terminal of the first capacitor, and a second terminal coupled to a reference node; and a resistive divider circuit coupled across the first capacitor and having an output terminal that delivers a voltage signal corresponding to a voltage across the first capacitor.

Abstract: To avoid the catastrophic failure of a drive, protection circuitry is configured to limit current in the DC bus capacitors. The drive may include an isolation circuit and a protection circuit having a comparator. The protection circuit may be configured to compare the voltage measured across a DC bus capacitor with a threshold voltage and activate the isolation circuit when the DC capacitor voltage exceeds the threshold voltage. The drive may also include a low voltage circuit coupled to the isolation circuit, where the low voltage circuit is configured to interrupt the bypass signal to disengage the bypass circuit and activate the precharge circuit when the isolation circuit is activated. Accordingly, the current in the drive and to the DC bus capacitors is limited by the precharge circuit when the voltage of a capacitor in the DC bus exceeds a threshold.

Abstract: For open loop phase pre-charge, an apparatus includes a Switching Mode Power Supply (SMPS) charging diode and a charge generator. The SMPS charging diode pre-charges an SMPS to a regulation set point from at least one phase of an Alternating Current (AC) voltage. The charge generator is powered by the pre-charged SMPS. In response to detecting the regulation set point iteratively, the charge generator detects a specified phase angle of the AC voltage. In response to the specified phase angle, the charge generator iteratively generates a charging voltage during positive voltage interval that charges a Direct Current (DC) bus capacitor to a target DC bus voltage within a charging time interval. At least a portion of the charge generator comprises one or more of hardware and executable code, the executable code stored on one or more computer readable storage media.

Abstract: A power conversion system includes a sensing circuit to sense a system voltage of a DC bus circuit with a first DC bus terminal with a first voltage positive relative to a second voltage of a second DC bus terminal. The sensing circuit includes a first capacitor having a first terminal coupled to the second DC bus terminal, and a second terminal; a second capacitor having a first terminal coupled to the second terminal of the first capacitor, and a second terminal coupled to a reference node; and a resistive divider circuit coupled across the first capacitor and having an output terminal that delivers a voltage signal corresponding to a voltage across the first capacitor.

Abstract: Power conversion systems, disclosed examples include power conversion systems, ground fault detection apparatus and methods to detect and identify ground faults in a power conversion system using AC coupling to sense a system voltage to determine a leakage flux linkage, and to identify a faulted converter phase based on a phase shift angle of the leakage flux linkage.

Abstract: A power conversion system includes a controller that generates switching control signals according to duty cycles for a current switching control cycle, and adjusts the duty cycles by a non-zero offset value according to a modulation index in response to the modulation index exceeding a non-zero threshold. A method includes computing first duty cycles according to a modulation index, generating a plurality of switching control signals according to the first duty cycles in response to the modulation index being less than or equal to a non-zero threshold, computing second duty cycles offset from the first duty cycles and generating the plurality of switching control signals according to the second duty cycles in response to the modulation index exceeding the non-zero threshold.

Abstract: Power conversion systems, ground fault detection apparatus and methods to detect and identify ground faults in a power conversion system using AC coupling to sense a system voltage to determine a leakage flux linkage, and to identify a faulted converter phase based on a phase shift angle of the leakage flux linkage.

Abstract: Power conversion systems, disclosed examples include power conversion systems, ground fault detection apparatus and methods to detect and identify ground faults in a power conversion system using AC coupling to sense a system voltage to determine a leakage flux linkage, and to identify a faulted converter phase based on a phase shift angle of the leakage flux linkage.

Abstract: Precharging systems and methods are presented for precharging a DC bus circuit in a power conversion system, in which precharging current is connected through a precharging resistance coupled between only a single AC input line and the DC bus circuit when the DC bus voltage is less than a non-zero threshold, and a controller individually activates controllable rectifier switching devices when the DC bus voltages greater than or equal to the threshold using DC gating or pulse width modulation to selectively provide a bypass path around the precharging resistance for normal load currents in the power conversion system.

Abstract: Power converter modules and parallel conversion systems are presented in which the modules are provided in a rollable enclosure having AC and DC electrical connections, and an interior including a switching circuit with switching devices individually connected between a corresponding AC node and a corresponding DC node for operation as either a rectifier or an inverter and an internal filter circuit with inductors individually connected between a corresponding AC node of the switching circuit and a corresponding AC electrical connection, with a built-in blower or fan to cool the filter circuit during operation.

Abstract: Power conversion systems, disclosed examples include power conversion systems, ground fault detection apparatus and methods to detect and identify ground faults in a power conversion system using AC coupling to sense a system voltage to determine a leakage flux linkage, and to identify a faulted converter phase based on a phase shift angle of the leakage flux linkage.

Abstract: Precharging systems and methods are presented for precharging a DC bus circuit in a power conversion system, in which precharging current is connected through a precharging resistance coupled between only a single AC input line and the DC bus circuit when the DC bus voltage is less than a non-zero threshold, and a controller individually activates controllable rectifier switching devices when the DC bus voltages greater than or equal to the threshold using DC gating or pulse width modulation to selectively provide a bypass path around the precharging resistance for normal load currents in the power conversion system.

Abstract: Output voltage feedback systems and methods are provided for controlling voltage source inverter output voltages using low bandwidth buffer circuitry and low A/D converter sample rates to sense and sample PWM output voltage waveforms to provide an estimated volt-second value for phase voltage or line-line voltage as feedback for controlling the voltage source inverter.

Abstract: Output voltage feedback systems and methods are provided for controlling voltage source inverter output voltages using low bandwidth buffer circuitry and low A/D converter sample rates to sense and sample PWM output voltage waveforms to provide an estimated volt-second value for phase voltage or line-line voltage is feedback for controlling the voltage source inverter.

Abstract: Power converter modules and parallel conversion systems are presented in which the modules are provided in a rollable enclosure having AC and DC electrical connections, and an interior including a switching circuit with switching devices individually connected between a corresponding AC node and a corresponding DC node for operation as either a rectifier or an inverter and an internal filter circuit with inductors individually connected between a corresponding AC node of the switching circuit and a corresponding AC electrical connection, with a built-in blower or fan to cool the filter circuit during operation.

Abstract: Motor drive apparatus and methods are presented in which a standby controller uses at least one switching device to power an inverter in a normal mode and to remove power from the inverter and other motor drive components during a standby mode for improved energy efficiency.