Abstract:
Power converters are presented having a precharging resistance and a normally closed precharging switch with a controller to limit inrush current during precharging of a DC bus circuit capacitance while preventing operation of rectifier switching devices until the DC bus voltage reaches a threshold value, and then to open the precharging switch and allow selective operation of the rectifier switching devices, with a second capacitance coupled across a rectifier output to mitigate rectifier output voltage spikes due to common mode currents flowing through a DC link choke, and additional capacitors coupled between positive and negative rectifier output terminals and ground to limit the rectifier output terminal voltages with respect to ground.
Abstract:
Systems and methods are provided for pre-charging the DC bus on a motor drive. Pre-charging techniques involve pre-charge circuitry including a manual switch, an automatic switch, and pre-charge control circuitry to switch the automatic switch between pre-charge and pre-charge bypass modes in response to an initialized pre-charge operation, input voltage sags, and so forth. In some embodiments, the pre-charge operation may be initialized by switching the manual switch closed. In some embodiments, the pre-charge operation may also be initialized by a detected voltage sag on the DC bus. The pre-charge circuitry may also be configured to disconnect to isolate a motor drive from the common DC bus under certain fault conditions.
Abstract:
The present techniques include methods and systems for detecting a failure in a capacitor bank of an electrical drive system. Embodiments include using discharge resistors to discharge capacitors in the capacitor bank, forming a neutral node of the capacitor bank. In different capacitor configurations, the neutral node is measured, and the voltage is analyzed to determine whether a capacitor bank unbalance has occurred. In some embodiments, the node is a neutral-to-neutral node between the discharged side of the discharge resistors and a neutral side of the capacitor bank, or between the discharged side of the discharge resistors and a discharged side of a second set of discharge resistors. In some embodiments, the node is a neutral-to-ground node between the discharged side of the discharge resistors and a ground potential.
Abstract:
A system for manufacturing an industrial automation drive includes a carrier frame configured to hold one or more semiconductor devices for use in the industrial automation drive. The carrier frame includes a set of fasteners disposed around an internal wall of the carrier frame such that each fastener of the set of fasteners includes an angled edge and a horizontal edge. Each fastener of the set of fasteners is configured to toollessly couple a power circuit board having the semiconductor devices to the carrier frame by bending from a first position when the power circuit board is pushed against the angled edge and returning to the first position when the power circuit board is pushed past the horizontal edge.
Abstract:
Systems and methods are provided for pre-charging the DC bus on a motor drive. Pre-charging techniques involve pre-charge circuitry including a manual switch, an automatic switch, and pre-charge control circuitry to switch the automatic switch between pre-charge and pre-charge bypass modes in response to an initialized pre-charge operation, input voltage sags, and so forth. In some embodiments, the pre-charge operation may be initialized by switching the manual switch closed. In some embodiments, the pre-charge operation may also be initialized by a detected voltage sag on the DC bus. The pre-charge circuitry may also be configured to disconnect to isolate a motor drive from the common DC bus under certain fault conditions.
Abstract:
A system for manufacturing an industrial automation drive includes a carrier frame configured to hold one or more semiconductor devices for use in the industrial automation drive. The carrier frame includes a set of fasteners disposed around an internal wall of the carrier frame such that each fastener of the set of fasteners includes an angled edge and a horizontal edge. Each fastener of the set of fasteners is configured to toollessly couple a power circuit board having the semiconductor devices to the carrier frame by bending from a first position when the power circuit board is pushed against the angled edge and returning to the first position when the power circuit board is pushed past the horizontal edge.
Abstract:
The present techniques include methods and systems for detecting a failure in a capacitor bank of an electrical drive system. Embodiments include using discharge resistors to discharge capacitors in the capacitor bank, forming a neutral node of the capacitor bank. In different capacitor configurations, the neutral node is measured, and the voltage is analyzed to determine whether a capacitor bank unbalance has occurred. In some embodiments, the node is a neutral-to-neutral node between the discharged side of the discharge resistors and a neutral side of the capacitor bank, or between the discharged side of the discharge resistors and a discharged side of a second set of discharge resistors. In some embodiments, the node is a neutral-to-ground node between the discharged side of the discharge resistors and a ground potential.