摘要:
Control of an induction motor is carried out to limit damaging arcing stress and mechanical stresses placed on the control contactor assembly and the induction motor resulting from the simultaneous or synchronous breaking and making of contactors employed to connect the windings of the motor to a power supply. Asynchronously connecting the windings to the power supply via the asynchronous or non-simultaneous closing of the contactors of a modular contactor assembly reduces the potentially damaging transient current, the associated torque oscillations, and mechanical stresses. The present invention is particularly applicable to delta motors that are started with its windings in a star or wye configuration followed by the reconnection of the windings in a delta configuration when the motor is at normal running speed.
摘要:
The present invention provides an electrical isolation apparatus having independently controllable contactors. The isolation apparatus includes a contactor for each phase or pole of an electrical device as well as each phase or pole of a load. Each contactor is constructed so that each includes multiple contact assemblies that may be independently controlled to open and close. Moreover, the contactors within a single contactor assembly or housing can be independently controlled so that the contacts of one contactor can be opened without opening the contacts of the other contactors in the contactor assembly. Additionally, the contactors are constructed and controlled such that a single line side contactor and a single load contactor open simultaneously when an open circuit condition is desired.
摘要:
A method an apparatus is disclosed for preventing contact welding during fault conditions. This fault current tolerable contactor includes two magnetic components, one in operable association with the movable contacts, and the other fixable attached above the movable contacts such that when a fault condition occurs, a high magnetic force is created to draw the two magnetic components together thereby opening the contacts. The magnetic force keeps the contacts open at least until current zero, and preferably a defined time thereafter to provide enough time for the contacts to cool and prevent welding upon the closure of the contacts.
摘要:
A method and apparatus to independently control the closing or making of contactors in a modular contactor assembly is disclosed. The apparatus includes a contactor assembly having multiple contactors such that each contactor is separately controlled such that one contactor may be closed without the other contactors of the assembly being closed. The contactors are arranged such that a pair of contactors is caused to close following a zero-voltage crossing of a power signal. A third contactor is caused to close after the pair of contactors has closed.
摘要:
According to some embodiments, a communication module 120 may be configured to transmit data packet traffic and a management module 110 may be configured to shape the data packet traffic transmitted by the communication module 120. The management module 110 may shape the data packet traffic by buffering data packets routed at different times to the communication module 120 based on at least one power management factor.
摘要:
A power circuit configured to generate and distribute DC electrical power, the power circuit includes a photovoltaic (PV) system that includes an array of PV modules electrically coupled to a combiner box, and an inverter positioned to receive DC electrical power from the array of PV modules and output AC electrical power. The PV system also includes a signal generator coupled to a first portion of the PV system, and a signal detector coupled to a second portion of the PV system, the signal detector configured to detect secondary signals generated at a loose connection of an electrical joint in the PV system, wherein the secondary signals result from a signal generated by the signal generator.
摘要:
A technique for determining a set of calibration parameters for use in a model of a photo-lithographic process is described. In this calibration technique, images of a test pattern that was produced using the photo-lithographic process are used to determine corresponding sets of calibration parameters. These images are associated with at least three different focal planes in an optical system, such as a photo-lithographic system that implements the photo-lithographic process. Moreover, an interpolation function is determined using the sets of calibration parameters. This interpolation function can be used to determine calibration parameters at an arbitrary focal plane in the photo-lithographic system for use in simulations of the photolithographic process, where the set of calibration parameters are used in a set of transmission cross coefficients in the model of the photo-lithographic process.
摘要:
Engineered fusion proteins comprising photochromic protein domains are disclosed. In particular, the inventors have constructed fusion proteins containing photoswitchable photochromic fluorescent protein domains linked to selected proteins and shown that such fusion proteins can be used to control the activity or localization of selected proteins with light.
摘要:
The disclosure discloses a system and method for sharing multiple network resources on a stand-alone machine. The system includes: a task managing subsystem configured to receive a downloading task, acquire a task parameter, divide the downloading task into M downloading subtasks and allocate the M downloading subtasks respectively to respective network equipments, merge downloaded messages after the respective downloading subtasks are completed, and report the merged message; an equipment managing subsystem configured to maintain an equipment status of each network equipment and provide an equipment parameter; a protocol managing subsystem configured to encapsulate a downloading request and send the downloading request to a route managing subsystem, receive and parse a message sent by the route managing subsystem, and store the parsed message in a corresponding memory space; and the route managing subsystem configured to maintain a route table, forward the downloading request to a network side via a corresponding network equipment, and send a message returned by the network side to the protocol managing subsystem. By integrating multiple network equipments on the stand-alone machine, the disclosure achieves sharing of multiple network resources, maximizing utilization of network resources of the stand-alone machine, which meets the demand of a high-speed network application.