Rockwell Automation Technologies Incorporated

Rockwell Technologies, Inc.

Nickolay N Guskov

Gary Leonard Skibinski

Dongsheng Zhou

Zhijun Liu

Lixiang Wei

Russel J Kerkman

Bruce W Weiss

Ahmed Mohamed Sayed Ahmed

James A Ulrich

Jeffrey D McGuire

Brian R Buchholz

Walt A Maslowski

James P Clavette

Jesus Mariscal

Steven J Krautkramer

James J Valasek

Carlos Rodríguez Valdez

David Dahl

Bruce A Hachey

William Jonn Sarver

William John Sarver

Systems, methods and power converters are disclosed to provide regulated individual DC output signals to anode structures using a PWM inverter to generate a first AC signal, a sinewave filter to provide a filtered AC signal, a multiphase isolation transformer to provide a plurality of isolated AC signals, a multi-pulse diode bridge rectifier to provide a DC rectifier output signal, an output filter to provide a filtered DC rectifier output signal, and a blocking diode to provide the filtered DC rectifier output signal.

Adjustable AC/DC conversion topology to regulate an isolated DC load with low AC ripple

A transformerless parallel active rectifier system includes N multiphase common mode inductors directly connected to a shared multiphase AC input with no intervening transformer, and N active rectifiers coupled to respective ones of the N multiphase common mode inductors and having respective DC outputs coupled to a shared DC bus, where N is an integer greater than 1. The N active rectifiers have ground current regulators and are synchronized to provide DPWM switching control signals synchronized to one another to regulate their respective ground currents and concurrently regulate the shared DC bus voltage.

Transformerless parallel AFE with ground current regulator

A precharge system for precharging a DC bus circuit includes a first input, first and second circuit branches, and a controller, where the first circuit branch includes a first contactor between the first input and an AC to DC converter, the second circuit branch has: a disconnect switch coupled to the first input; a variable frequency drive (VFD) with an AC input coupled to the disconnect switch; an inductor coupled to an AC output of the VFD; and a second contactor coupled to the inductor. The precharge VFD provides precise control of the precharge operation such as charging time, current limiting, short-circuit and ground fault protection, monitoring DC Bus capacitance and verifies the health of the shared DC bus circuit through startup diagnostic. The controller opens the first contactor and closes the second contactor and the disconnect switch in a first mode to precharge the DC bus circuit using the VFD, and in a second mode, the controller closes the first contactor and opens the second contactor and the disconnect switch.

DC bus precharge system

Electroplating and painting systems, methods and power converters are disclosed to provide regulated individual DC output signals to anode structures distributed in a plating solution in a tank to promote formation of plating material on a workpiece using a PWM inverter to generate a first AC signal, a sinewave filter to provide a filtered AC signal, a multiphase isolation transformer to provide a plurality of isolated AC signals, a multi-pulse diode bridge rectifier to provide a DC rectifier output signal, an output filter to provide a filtered DC rectifier output signal, and a blocking diode to provide the filtered DC rectifier output signal to the corresponding tank anode structure.

Disclosed examples include enclosures with segregated or divided cooling paths and improved arc flash resistance. In one example, a TYPE 12, 50 DEGREE C. ambient common bus power conversion enclosure design provides enhanced arc flash protection & segregated cooling for high reliability of imbedded electronics. Example enclosures and systems can be used in association with AC/DC converters for motor drives or motor control centers, and/or for electroplating or painting systems with modular anode control (MAC) systems to implement an anodic DC electroplating for workpieces and other end use applications.

Arc flash resistant enclosure with segregated cooling

A transformer for converting 3 phase AC to 9 phase AC power is provided. The transformer comprising a laminated core, first, second and third coils constructed on the laminated core, each coil including several windings. Cooling ducts are provided in each coil, wherein at least one cooling duct is disposed between the laminated core and an adjacent winding of the respective coil. The transformer further includes first, second and third input terminals each linked to the first, second and third coils, and configured to receive a first, second and third phases of input AC power and first through ninth output terminals linkable to first through ninth output power lines.

Multi-phase transformer

A method and apparatus for identifying a ground fault in a motor drive system that includes at least one three phase power conditioner that is linked to three phase supply lines and to positive and negative DC buses, the method comprising the steps of controlling the power conditioner at an operating frequency to convert power, while controlling the power conditioner to convert power, controlling the power conditioner to apply a common mode signal on each of the three phase supply lines where the common mode signal has a frequency that is different than the operating frequency, sensing the common mode signal on at least one of the three phase supply lines and when the common mode signal on the at least one of the three phase supply lines is greater than a threshold level, indicating that a ground fault has occurred.

High resistance ground protection employing AC drive characteristics

A nine-phase AC to DC power converter system may exhibit current unbalance problem among bridges due to two reasons: slight voltage magnitude difference among different sets of three-phase supplies and pre-existing voltage harmonics in the power supply lines. Since the unpredictability of the pre-existing harmonics and manufacturing uncertainty of the nine-phase power supply (it is usually a three to nine phase transformer), all devices in the rectifier bridges are required to carry much higher than necessary current magnitude and have to be designed oversize, as much as 100% up. Here we describe various topologies of harmonic blocking reactors to combat this problem. The described topologies can significantly improve this situation and thus avoid the over-sizing exercise (cost) when such converter system is built. The principle can be easily extended to any multi-phase AC to DC or DC to AC power conversion system of more than nine phases. The principle can be extended to any multi-phase converter system with more than nine phases.

Harmonic blocking reactor for nine-phase converter system

The invention includes an autotransformer for converting three-phase AC power to nine-phase AC power. The autotransformer includes three coils, each coil including a plurality of serial windings that together form a polygon. Nine output nodes are provided between adjacent winding pairs, the windings sized and arranged such that adjacent output voltages are separated by 40 degree phase shift and such that output voltage magnitudes are essentially identical. Both step-down and unity gain input node sets are provided wherein, when three-phase AC supply lines are linked to the step-down input set the output voltage is stepped down and when the three-phase AC supply lines are linked to the unity gain input set the transformer gain is unity. The invention also includes an isolation transformer having characteristics similar to those of the autotransformer.

Nine-phase transformer

The invention includes a transformer for converting three-phase AC power to nine-phase AC power. An autotransformer includes three coils, each coil including a plurality of serial windings that together form a polygon. Nine output nodes are provided between adjacent winding pairs, the windings sized and arranged such that adjacent output voltages are separated by 40 degree phase shift and such that output voltage magnitudes are essentially identical. Both step-up and unity gain input node sets are provided wherein, when three phase AC supply lines are linked to the step-up input set the output voltage is stepped up and when the three phase AC supply lines are linked to the unity gain input set the transformer gain is unity. An isolation transformer includes a secondary arranged like the autotransformer configuration described above.

The invention includes an autotransformer for converting three-phase AC power to twelve-phase AC power using only three coils (e.g., no primary or dead windings are required). The autotransformer includes three coils, each coil including a plurality of serial windings that together form a polygon. Twelve output nodes are provided between adjacent winding pairs, the windings sized and arranged such that adjacent output voltages are separated by 30 degree phase shift and such that output voltage magnitudes are essentially identical. In some embodiments step-up, step-down and unity gain input node sets are provided while in other embodiments unity gain and either step-up or step-down input node sets are provided. The invention also includes an isolation transformer configuration that uses a secondary configuration that is identical to inventive autotransformer configurations.

Growing community of inventors

Mequon, WI, United States of America

Nickolay N Guskov