Abstract:
A high voltage DC switchyard comprises at least one busbar, at lest two DC lines connected to said at least one busbar through DC breakers comprising a section of at least one semiconductor device of turn-off type and rectifying member in anti-parallel therewith. At least one said DC line is connected to at least one said busbar through a unidirectional said DC breaker, i.e. a DC breaker that may only block current therethrough in one direction.
Abstract:
An arrangement for overload restriction associated with a system adapted for electrically driving a vehicle along a roadway. The vehicle is provided with a current collector, which is displaceable up and down and sideways in relation to the direction of transportation, in order to be brought into mechanical and electrical contact with elongated tracks positioned below the roadway and comprising a conductor adapted to be supplied with current and put under voltage. The arrangement comprises a circuit for limiting the momentary power outlet connected to said vehicle-external power source and being adapted to supply power to said conductor within the roadway section via said switch when the vehicle passes.
Abstract:
An arrangement for metal detection related to a system adapted for electrically driving a vehicle along a roadway. The vehicle is provided with a current collector which is displaceable up and down and sideways in relation to the direction of transportation, in order to be brought into mechanical and electrical contact with elongated tracks positioned below the roadway and comprising a conductor adapted to be supplied with current and put under voltage. The detecting arrangement, comprises one or more coils arranged for sensing the variation of the magnetic field, based on a horizontal and/or vertical distance between the coils and metal parts belonging to the one or more elongated tracks.
Abstract:
A Voltage Source Converter having at least one phase leg connected to opposite poles of a direct voltage side of the converter and comprising a series connection of switching cells has inductance means comprising a plurality of inductors built in in said series connection of switching cells and connected in series with these cells by being connected to terminals thereof.
Abstract:
In a method for controlling a Voltage Source Converter having at least one phase leg comprising a series connection of switching elements, in which each said element has at least two semiconductor devices of turn-off type, at least two free-wheeling diodes connected in parallel therewith and at least one energy storing capacitor, each said switching element is controlled according to a Pulse Width Modulation pattern so that each switching element is switched to change between applying a zero voltage and the voltage across its capacitor across its terminals each time a saw tooth voltage wave for that switching element crosses a reference alternating voltage belonging to that switching element.
Abstract:
This invention concerns a rail structure (70, 71, 72, 73) in a vehicle-related system (S) for driving an electric and by one or more batteries conveyable vehicle (1) along a stretch of a track in a roadway section (2a1) and related to a roadway, comprising (a″) by one or more individual electric motors (5) drivable vehicles (1), and “b” a plurality of roadway sections (2a1, 2a) which may subdivide the stretch of roadway. Said tracks (51, 52) are in a cross section oriented in parallel in a rail structure (70), said rail structure (70) having external, of metal made, wall sections (71, 72) and a partition (73) separating the external wall sections. A first conductor surface ( ), which may be subjected to voltage, is allotted a lower portion for a first track (51). A second conductor surface (4b), which may be subjected to voltage, is allotted a lower portion for a second track (52).
Abstract:
The present invention has its application to a system for driving an electric and by one or more batteries powered vehicle along a roadway, comprising “a” one or more vehicles, which may be driven by an individual electric motor or motors and where in the respective vehicles exhibit a power-controlling control circuit for creating the necessary power and/or speed control and wherein required power i.a. can be provided primarily by a chargeable can be provided primarily by a chargeable battery set associated with the vehicle and “b” a plurality of road sections road portions divisible for the roadway, each being allotted one or more vehicle external electric stations for charging the battery set thereby and/or for supplying necessary power and energy for driving the vehicle. The underneath side of the mentioned vehicle is provided with a contact means displaceably positioned up and down and sideways, counted in the direction of transportation. Said roadway and its road sections or portions exhibits an elongated track or groove, each road section is supporting two rails in the groove and disposed under the driving path of the road section or portion. The rails being supplied with current and voltage. Said contact means is coordinated with a control equipment for creating simple adaptation of the contact means for registering the contact means for mechanical and electrical contact against said two rails.
Abstract:
A modular HVDC converter system including a high voltage direct current network, and at least two DC/AC converters being connected in series to the HVDC network. Each of the DC/AC converters is arranged to provide AC to a separate AC load.
Abstract:
A semiconductor power module includes at least two sub modules. The sub modules include at least one respective transistor having a collector, an emitter, and a gate. The module includes a connection arrangement having a collector terminal unit for connecting the collectors of the at least two sub modules collectively to external circuit components, at least two emitter terminal units for connecting the respective emitters of the at least two sub modules individually to external circuit components, and at least two gate terminal units for connecting the respective gates of the at least two sub modules individually to external circuit components.
Abstract:
In a method for controlling a Voltage Source Converter having at least one phase leg comprising a series connection of switching elements, in which each said element has at least two semiconductor devices of turn-off type, at least two free-wheeling diodes connected in parallel therewith and at least one energy storing capacitor, each said switching element is controlled according to a Pulse Width Modulation pattern so that each switching element is switched to change between applying a zero voltage and the voltage across its capacitor across its terminals each time a saw tooth voltage wave for that switching element crosses a reference alternating voltage belonging to that switching element.