摘要:
A multi-phase converter includes a plurality of phase paths. Each phase path includes at least one dc-link that is independent from every other phase path dc-link such that each output phase voltage is generated from a corresponding dc-link voltage source that can be different from every other phase voltage dc-link voltage source. A total dc-link voltage level is determined for each output phase voltage. A common-mode injection voltage is calculated based on all dc-link voltage levels and all phase reference voltages. Each phase path reference voltage is then adjusted based on the calculated common-mode injection voltage, such that each generated output phase voltage level is adjusted in response to its corresponding adjusted reference voltage.
摘要:
A power converter includes an active front end (AFE) that is coupled by a dc link stage to a plurality of H-bridge inverters. One or more multi-phase electro-magnetic energy conversion devices, such as transformers or electric machines, with open windings that are connected to only the AFE or only the H-bridge inverters or to both the AFE and H-bridge inverters, provide a regenerative or partial regenerative power converter.
摘要:
Authorized or unauthorized opening of access to equipment of a telecommunications network in a control center is detected on the basis of alarm messages. The telecommunication network is a mobile radio network or a hard-wired network. The control center monitors the access equipment and transmits alarm messages as a result of the access equipment being opened. A message is first transmitted by a signaling device to a signaling server before the access equipment is opened. Then the server, after receiving the message from the signaling device, generates an alarm-suppression information item. This alarm-suppression information item is evaluated in the control center, and, whenever an alarm message is received, this message is compared with the alarm-suppression information items and the alarm message is filtered in the event of a positive association.
摘要:
A method of operating a neutral point clamped (NPC) three level converter is provided. The NPC converter includes at least two legs, each leg comprising first and second top switches connected in series at a first mid point. The converter further includes first and second bottom switches connected in series at a second mid point, and first and second middle switches connected in series at a third mid point therebetween. The first top and second bottom switches are connected in series at a DC link and the first and the second middle switches are connected between the first and the second mid points. Each of the top, bottom and middle switches has an antiparallel diode thereacross. The method includes alternately switching the first and second top switches to ON state when the first middle switch is in ON state and the second middle switch is in OFF state. The method also includes alternately switching the first and the second bottom switches to ON state when the first middle switch is in OFF state and the second middle switch is in ON state.
摘要:
A method and system for a control power supply system is provided. The control power supply system includes a first conductor configured to carry a direct current (DC) electrical current from a source to a load, a second conductor configured to carry the DC electrical current from the load to the source, a electrical device electrically coupled in series with at least one of the first and second conductor. The electrical device is configured to fail in a shorted condition such that failure of the electrical device maintains a direct current (DC) ring bus including the first and second conductor. The control power supply system also includes a control power circuit electrically coupled in parallel with at least a portion of the electrical device such that a DC voltage across at least a portion of the electrical device provides a DC voltage supply to the control power circuit.
摘要:
A vehicle includes a power connector configured to mate with an electrical power grid receptacle and receive a grid power therefrom and a heating and cooling system electrically connected to the power connector to receive grid power therefrom and configured to modify a temperature the vehicle cabin. The vehicle also includes a temperature control loop configured to selectively activate and control the heating and cooling system and a controller configured to receive a first input signal comprising a desired vehicle activation time and a second input signal comprising a starting vehicle cabin temperature and a desired vehicle cabin temperature. The controller determines a temperature control loop activation time based on the first and second input signals that is prior to the desired vehicle activation time and transmits an activation signal to the temperature control loop at the temperature control loop activation time to activate the heating and cooling system.
摘要:
Embodiments presented herein are directed to a system comprising, a semiconductor device including a semiconductor junction, an optical fiber, a proximal end of said optical fiber in electromagnetic communication with said semiconductor junction, and a processing unit in electromagnetic communication with a distal end of said optical fiber, said processing unit capable of receiving electromagnetic information available at said distal end and processing the electromagnetic information.
摘要:
A multilevel converter includes a plurality of phase legs each having at least two inner switching devices, at least two outer switching devices, at least two clamping diodes, a split DC link and a switching device failure detection circuit. The switching device failure detection circuit includes a logic module for each of the switching devices, a voltage calculation module and a failure detection algorithm. The logic module generates a blocking state logic signal by comparing a switching device voltage and a threshold reference voltage and the voltage calculation module determines an expected voltage blocking state for each of the switching devices based on the gate drive signals of the switching devices and an output current direction. The failure detection algorithm detects a failure condition in any of the switching devices based on the blocking state logic signals and the expected voltage blocking states of the switching devices.
摘要:
A semifinished leather product is produced from an animal hide by pretanning with the use of a chromium-free tanning agent and of a clay mineral which, after stirring for 30 minutes in water at 50° C. at a circumferential rotor speed of from 5 to 25 m/s, has a number average particle diameter of less than 2 μm or a bimodal particle size distribution with a first, finely divided fraction whose number average particle diameter is less than 0.5 μm and a second, coarser fraction whose number average particle diameter is less than 5 μm, determined in each case by the method according to ISO 13320-1, by combined laser light diffraction and light scattering, a proportion of the first, finely divided fraction being from 10 to 90% by weight, and drying of the pretanned animal hide to a water content of from 5 to 45% based on the total weight of the semifinished leather product.